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ENG 1182

Lab-on-a-Chip Project Description Document

Lab-on-a-Chip Project Description

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Table of Contents

Introduction…………………………………………………………………………………………..4-5

Overall Project Objectives……………………………………………………………….…………6-7

Project Milestones Outline and Checklist…………………………………………………….……..8

Chip Design and Operation Process Summary……………………………………..…………..…9

Design Deliverables…………………………………………………………………………….……10

Project Schedule……………………………………………………………………………..…..11-13

Project Notebook/Reporting………………………………………………….………….14-15

Chip Requirements………………………………………………………………………….……16-24

Sample Chip Drawings…………………………………………………………………………..25-26

GTA Meetings…………………………………………………..…………………………….………27

Nanotech Lab Tour………………………………………………………….……………………….28

Testing the Chip…………………………………………………………………………………..29-30

Final Report……………………………………………………………………………………….31-37

Oral Presentation…………………………………………………………………………………….38


Introduction and Background

Nanotechnology offers many potential areas for product improvements. One field, in particular, that is being aggressively explored is the biomedical field. An example of a biomedical application that could greatly improve disease diagnosis is the development of Labs-on-a-Chip (LOC). These small, portable, inexpensive devices can be used to quickly and conveniently run tests on very small amounts of fluids, such as blood, when and where needed. This project will explore the design and use of a LOC to study operational aspects of devices of small scale.

Fluorescein is a chemical that is used to detect an eye disorder known as dry eye syndrome. This disorder reduces the flow of tears to the eyes, creating symptoms such as itching, burning, redness, and blurred vision. It is estimated that as many as 10 million people suffer from this ailment. To diagnose this problem, physicians need to measure the flow rate of tears coming into the eyes. By putting a small amount of fluorescein into the eye and measuring the change in its concentration in tears over time physicians can determine tear flow rate. As new tears enter the eye, the fluorescein concentration is decreased. The tear flow rate can be compared to normal flow rates to identify the “dry eye” problem.

Typically this test is done with expensive instruments in a doctor’s office. Samples of tears are taken from the eye in micro-liter amounts. This project’s objective is to design a cheap, portable Lab-on-a-Chip, LOC, design to measure the concentration of fluorescein. The benefit of this device would be to greatly reduce the cost of equipment required (fluorophotometers) as well as to provide a product that is readily portable. Portability is very helpful in situations where older or disabled patients find it difficult to travel to a doctor’s office.

The LOC project consists of designing two different chip designs. The first chip will be designed in the early part of the semester and the second chip, which will be designed later. The two-step design approach will allow for improvements from the first design and ultimately enhance LOC performance.

Additional Lab Components

In addition to the hands-on lab experiences and documentation described above, the following components are provided to enhance the lab experience and relate current nanotechnology research to the microfabrication analog provided within the confines of the lab.

Nanotechnology Teaching Modules (NTM)

Nanomanufacturing involves the precise manipulation and placement of individual molecules and an understanding of scientific principles applied at the molecular scale. An important part of this lab project is developing hands-on experience with micromanufacturing and knowledge of the challenges you would face in reducing the size scales a further 3 orders of magnitude to the nanoscale domain. To help with the latter, we have commissioned several


faculty members around the university whose primary research is in an aspect of nanotechnology to write short modules on a specific topic. These modules form an integral part of your lab assignments and will comprise a significant part of your lab memos. They are assigned at times that best correspond to the subject matter of specific segments of the design-build project. When a module is assigned you are to read the module and answer the assigned questions from the module as a part of your lab memo. There are also quizzes on Carmen that need to be completed. The modules are available in this lab packet.

Nanotechnology Lab Tour

Students will also go on a tour of some of the nanotechnology labs on the OSU campus, and will write a summary of this experience. To prepare for this tour and for the requirements for the summary, see the Lab Tour Summary section of this document.


Overall Project Objectives

Project Management and Teamwork – To successfully bring any complex project to completion requires proper planning and the coordinated effort of a group of people. To help your team achieve this goal, you will be introduced to the basics of project management and teamwork. This includes, but is not limited to: time management and task scheduling, team communications and meetings, fair division of labor and team member responsibilities. You will be expected to produce related documents such as a work breakdown structure, a project schedule, and team meeting records, all of which must be regularly updated and kept in the team project notebook. Additional information is included in the Project Management and Project Notebook sections of this document.

Design Process – Rarely, if ever, does a new design work perfectly the first time. Your design project will likely be no exception to this. While it is a lot of fun to dive right in and start prototyping any sort of project, your team will reach a useful design much sooner if you follow a more formalized approach to the design process. In short, it consists of: identifying the project requirements and constraints, gathering background information, brainstorming, identification and management of materials, initial analysis & design, and the build/test/modify/document cycle with two iterations. As part of this process, you will produce the initial design, document any revisions to it as they occur, and produce the 1st and 2nd design documentation that accurately reflects your designs. You should also keep the initial, 1st and 2nd designs, with all revisions for both chip design, in your project notebook. For more details, read the Chip Requirements, Project Management and Project Notebook sections of this document.


Project Documentation – Your project documentation consists of three parts:

1. The team project notebook: The team project notebook is the complete documentation of the design project, and will be reviewed on a weekly basis starting on the third lab session. It should contain:

your lab memos your paper designs your team meeting minutes your project management documents anything else of importance relating to the design project.

The complete requirements are in the Project Notebook section of this document.

2. The Oral Presentation: The oral presentation is an overview of your design project experience.

3. The final written report. The final written report is a complete summary all aspects of your design. The oral presentation and final written report are both due per class schedule near the end of the semester.

The requirements for each of these are described in detail in the Oral Presentation and Final Written Report documents. You may also refer to the Technical Communications Guide for further help.

[Please see the Chip Requirements and Project Notebook/Reporting sections for specific requirements about project documentations]

Checklist and Outline of Schedule of Milestones for the LOC Project


(Does not include all assignments, only major milestones)

Early Part of the Semester

Review this Project Description Document, “hands on” experimentation with generic designWork on paper design, Begin Project Notebook, Team agreementDue: Initial Design Sketch, Update Project Notebook

Due: Preliminary 1st Design

Due: GTA Meeting #1Due: 1st Design and Calculations dueDue: Project ScheduleDue: Lab Tour Summary

Mid Semester

Continual updating of Project Notebook

Due: 1st Chip Design testing. GTA Meeting #2Due:, 2nd Chip Design and Calculations due

2nd Chip Testing

End of the Semester

Selection of chip for Final test

Final TestOral PresentationDue: Final Written ReportDue: Completed Project Notebook

[Note: the project notebook must be updated throughout the semester]


(see pages 4-7………)

(see pages 16; 11-15 )

(see pages 16; 11-15 )

(see page 27………..)

(see pages 16-26; 11-13; 28…………….)

(see pages 29; 27…..)

(see pages 16-26…...)

(see pages 29-30…...)

(see pages 38; 31-37; 14-15…………………)

(see page 16………...)

Chip Design and Operational Process Summary

Overview The goal of the lab is to develop, test and document a lab-on-a-chip prototype designs based on the requirements listed in this document.

Each team will create two prototype designs for a portable device to be used for the detection of fluorescence of a chemical solution. Through the course of the initial labs the teams will experiment with a generic prototype of a lab-on-a-chip which will expose the teams to the necessary operational and equipment characteristics to enable them to create new designs. Actual prototype devices will be manufactured from Solidworks drawings of these designs and will be tested and calibrated for use in a final test evaluation.

Lab Management

Lab-on-a-Chip Construction Materials

Each team will be provided with standard lab-on-a-chip kits, parts for the sensor circuits, and a storage bin, distributed as needed on a weekly basis. There will be additional materials for each lab to experiment with the generic designs. The full list of materials is provided in the equipment list included in this Project Description Document. See the Table of Contents.

No additional materials may be used. Parts for the construction of the sensor system will be provided for the semester. A quarterly checklist must be completed when each team receives these materials and will be used for check-in of materials after final testing.


Design Deliverables

Student teams will be required to provide two designs each for their lab-on-a-chip device. The two designs will differ because two different styles of chipholders will be used. More details are described in the Chip Requirements section.

The matrix below outlines the various submission stages for your designs and process descriptions, and the deliverables for each submission:

Design Deliverables

Each team will provide two chip designs for the LOC device – One design for each chipholder

Initial Sketch Design Submission for the 1st chip

Preliminary 1st design

1st Chip Design Submission

2nd chip Design Submission

Hand-drawn sketch Required Not required Not required Not required

Solidworks Drawings of designs

Not required

Dimensioned Solidworks Part File to GTA

Dimensioned Solidworks Part File to GTA

1.Printout of dimensioned drawings

Dimensioned drawing NOT needed

2. Send Solidworks Part file to GTA

Operational Process

Not required Not required Refer to

page 20 Revised


Assignment

Materials to be submitted

Calculations

Not required

Detection Well Volume

Refer to page 20 Revised

Due dates for each of these submissions will be as per the class schedule.

Your Initial sketch designs and 1st chip Design will be reviewed by the instructional staff prior to the 2nd design submission. Your team will be expected to incorporate the necessary changes resulting from the 1st chip design reviews and from your lab experience with it prior to 2nd Design submission. Your team can further modify your operational process as needed based on experimentation and practical knowledge obtained from the labs. Your operational modifications will be required for final testing. You will also include it in your team’s final written report. Be sure to incorporate all changes in a timely manner for review in the team project notebook.


Project Schedule Grading Guidelines

Project Management Guidelines: Project Planning and Scheduling

Introduction

An important part of any project is proper planning early in the process. This involves identifying and analyzing the requirements, translating them into tasks, and then mapping the tasks to the available resources and timeframe. For this project each team should examine the syllabus and read the project description document to understand all of the deliverables required for this project. Using this information and taking advantage of the skills of the members of your team, you can then start more detailed planning and scheduling. This project schedule becomes an important tool for your team to use throughout the project execution to determine your progress toward your deadline.

The project schedule should be reviewed and updated at least weekly to identify tasks completed and status of your work. If initial tasks fall behind or overlooked tasks are identified, a re-plan effort needs to be done to establish a revised plan to meet the project deadline. The instructional staff will evaluate this project schedule weekly.

As per the class schedule, each team will be required to submit a project schedule. This submission is required before any construction can begin. Below is a list of major tasks that must be included in your schedule. You can add other major tasks as you feel appropriate to allow you to manage your project. You should also add subtasks under each major task to further break down the work as necessary. You should assign team members to them and identify a planned start and finish time for each task along with any dependencies between tasks. A sample of such a project schedule is shown following the task list.

Tasks for the Lab-on-a-Chip Project

Read project description document and syllabusTeam design brainstorming session(s)Develop Initial project planGTA Meeting# 1 GTA Meeting# 2 Benchmarking and generic design investigation observationsDevelop Initial sketch Develop operational process, calculate volumesPreliminary 1st Chip Design Revisions from design review meeting incorporated into Preliminary Design1st Chip Design2nd Chip DesignFurther revisions incorporated in Final designTesting of completed design


Notebook updatesLab 1 memo Lab 2 memoLab 3&4 memoLab 5 memoLab 6 memoLab toursLab tour summaryNTM readings and discussion questionsElectronic circuit developed and workingTeam design meetingsPlan for division of work during lab timeFinal Test Final Written report – outline, draft, finalOral presentation

Project SchedulePossibl

e Points

Points Earned

Content: 8 pts Tasks (20 minimum) 2 Person(s) assigned 2 Estimated start and finish dates 2 Actual start and finish dates 2Format & Organization 2 ptsTOTAL 10 pts

EXAMPLE:


GENERAL COMMENTS:

**Grading Guidelines – 1 point will be deducted if these guidelines are not attached to the Project Schedule


Documentation and Reporting

Project Notebook

Description & Requirements

Each team will keep a notebook documenting their progress in the building of their project. Information about both chip designs need to be included throughout. A three-ring binder is recommended. The purpose of the notebook is to document your work and maintain a record of ideas and decisions made throughout the quarter, in order to create your final written report and oral presentation. Materials should include, but not be limited to, the project description, project schedule, the team working agreement, lab reports, design documentation, handout materials, meeting notes, sketches, and all assignments directly related to the final written report (see below for list of required elements). Your TA or instructor will check this notebook each week in lab as it counts as part of your grade. The notebook will be turned in the last day of class, along with your final written report.

1. Table of Contents : The table of contents should reflect some organizational structure. In the past, notebooks have been organized by type of document (e.g. sketches, meeting notes, lab reports, etc…) and also chronologically. This section should be typed and page or section numbers should be provided. Major items in the Table of Contents should correspond to tabs in the Project Notebook. Minor items in the Table of Contents may be listed under the major items if necessary for quick reference.

2. Project Description: Include this entire packet of materials about the project.

3. Team Working Agreement

4. Project Schedule : Your project schedule should be a working document. Each week your schedule should be updated to reflect changes, additions, and modifications.

5. Lab Memos and Report : Simply include lab memos after they have been graded, plus the final written report.

6. Lab Tour Summary

7. Design Documentation : Initial sketches, 1st and 2nd designs along with all calculations (including MATLAB and/or Excel analysis) for both designs.

8. Meeting Notes/Brainstorming Record : Your meeting notes should accurately reflect the topics discussed and decisions reached (or not reached) in your team meetings. Sketches (if any) should accompany these notes.


9. Sketches : The only sketches required here are those not already contained in team meeting notes or lab reports. You should include any free hand or draft CAD drawings outside of the meeting notes or reports, including scrap drawings or ideas not used. Do not include Basics assignments.

10.Class Handouts : There is a possibility that you will be given updated project descriptions throughout the quarter.

11.All materials relevant to the Final Report: drafts of the written report, report outline, etc…

(check syllabus)

Project Notebook Grading Guidelines

The purpose of the project notebook is to document all work undertaken by the team during the course of the semester. When submitted, the project notebook should contain all the information required for the implementation of the project, in a step-by-step or sequential fashion. The project notebook is worth 40 points and the distribution of points and grading guidelines are listed below.

1. Notebook Organization (5 pts) –Use a three ring folder or binder. One approach is to copy all the project related documents from the ENG 1182 course packet and place it in the Project Notebook, tabbed for easy reference, Throughout the class period the GTAs will check the Project Notebook to make sure that it is up-to-date. These weekly checks are worth a total of five points.

2. Grading (35 pts)o Index and proper page numbering (5pts) o 2 phase GTA Meeting (15pts) o All lab related assignments, memos, and final written report (5 pts) o Brainstorming ideas, final design and related sketches, calculations and out-of-

class meeting notes (10 pts = 2+ 3 + 2 + 3) – All sketches should be neatly labeled and titled. Sketch of all designs will use Solidworks; pictorial views as well as fully dimensioned orthographic views should be furnished. Any change suggested by the Instructor/GTA to the final design should be implemented by the team. If not the team will lose half the credit of this section (10) and they might lose points during the final project testing as well.

Brainstorming ideas – 2 pts All Designs and related sketches – 3 pts All Designs calculations – 2 pts Out-of-class meeting notes – 3 pts

Timely submission – Each team needs to submit the Project Notebook at the start of the oral presentation session. Any late submissions are subject to a 30% deduction.


Chip Requirements

Initial Sketch Requirements for the 1st Chip

The initial design sketches can be a hand-drawn representation of your team’s ideas for your 1st chip design. Preparation for this design include reading the introduction, project objectives, and chip requirements section.

The sketch should be a two-dimensional representation of the chip design with proportional representation of the location and size of all features, i.e. wells, channels, logos.

Consider shape and size in all features, wells and channels that will encourage the flow of fluids in the direction desired.

Preliminary 1st Chip Design

Refer to the Class schedule for date requirements for the delivery of these designs. The 1st Chip Design should be created using Solidworks. The drawing must contain neat, two-dimensional representation of the lab-on-a-chip. It

must include the size, shape and location of all features.

1st Chip Design and Operational Design

Refer to the Class schedule for date requirements for the delivery of these designs. The 1st Chip Design should be revised using Solidworks and Operational Processes

should be typed and NEAT AND PROFESSIONAL in appearance. Design should incorporate review and commentary made by the instructional team in the preliminary design.

Calculations and/or notes for all feature sizes or shapes determined by other factors such as volume, flow, or sealing requirements.

Operational design specifically indicating how the chip will be used and the sequence of operations. This can be done with an ordered list such as an outline, or by flowchart.

2nd Chip Design and Operational Design

The 2nd chip design should be created using Solidworks. The operational design should be typed.

The 2nd chip design and operational designs should incorporate review and commentary made by the instructional team.

The drawings must contain neat, two-dimensional representations of the lab-on-a-chip. It must include the size, shape and location of all features.

Calculations and/or notes for all feature sizes or shapes determined by other factors such as volume, flow, or sealing requirements.


Operational designs specifically indicating how the chip will be used and the sequence of operations. This can be done with an ordered list such as an outline, or by flowchart.

The operational designs may continue to evolve up to the Final System Test. All changes must be documented in the Final Report.

LOC Design Requirements

Lab-on-a-Chip Design and Operational Design Requirements and Constraints

This section contains the following:

Chip design constraints and requirements Design Deliverables Solidworks Submission instructions Samples of Solidworks drawing submissions, and drawings of the chipholders

Chip Design Constraints and Requirements

Each team will create two chip designs - one will be designed to be accommodated in the 3-hole chip holder; the other will be designed to function in the 4-hole chip holder.The entire layout of both chips must fit within a 5.08 cm circle. Solidworks seed files will be provided to help create accurate designs.

Figure 1: Sample chip with all required features

I. To carry out the analysis the chip requires the following features:

a. Flow-through detection well, located in the exact center of the chip, in which the sample will be deposited. Confirm the necessary size by noting the 200 micron depth and the volume of fluid to be placed in the detection well. From this volume and depth, determine the necessary size (determine diameter if circular). It would be best to err a bit on the


larger side to be sure that the detection well can accommodate its intended contents.

CAUTION: Circular detection wells will most likely collapse owing to lack of support around the center. Other shapes should be considered.

b. At least one staging well to introduce the fluorescein solution into the chip.

c. Channels that connect the wells must be between 300 to 400 μm (micrometers or microns) in width.

d. Intersections of channels with wells may create sharp inside corners which cannot be manufactured. For any sharp internal corners add a curved lined with a radius of curvature of 200 microns. This applies to sharp corners on any features including logos. See figure 2 below.

Figure 2: Internal corners of features need to be rounded with a minimum radius of 200 microns

e. Staging wells and detection wells and the waste well must be accessible via the triangular pattern of access points on the chip holder. Chip design can be drawn over chip holder design (as a stencil) to accommodate this requirement.

f. Waste well to accept unused fluorescein solution sample from the detection well along with flushing fluid. The waste well should be sized to hold at least the volume of all the other wells combined.

NOTE: Large unsupported cavities in the design are more difficult to properly seal and fill in the finished product.


II. To carry out the analysis here are some additional considerations:

a. Detection well should be designed to store exactly 3 μl of fluorescein solution sample.

b. The depth of all features (wells and channels) in the chip will be 200 microns. A flat PDMS lid will enclose the features.

c. The analysis will require you to deliver solution from the staging wells directly and independently to the detection well. In other words, there must be a channel connecting each of the staging wells directly to the detection well.

d. There must be an exit channel from the detection well connecting to the waste well.

e. To reduce undesired flow between wells, the transfer line in and out of each well may contain a capillary check valve if deemed necessary. This can be accomplished by adding a very small circular well with a diameter approximately 3-5 times the width of the transfer line. The small well should be placed approximately 0.5 mm (500 μm) from the entrance or exit of the larger well but not touching that well. Figure 3 shows an example of a check valve. Check valves increase the pressure required for flow during a dry or unprimed state. Experimentation with non-traditional (i.e., non-circular and/or multistage, such as “fishbone” capillary check valves) capillary check valves is encouraged. Figure 4 depicts an alternate check valve design. Remember: NO SHARP CORNERS!

f. Different well shapes and channel entrance and exit shapes affect resistance to fluid flow. Tapered transitions, in contrast to sharp edges, can be used to diffuse flow.

g. In order to avoid the edges of the chip where possible trimming and sealing issues may arise, keep the design as far as possible from the edge of the chip, while still utilizing the access points provided by the


Figure 3: Capillary Check valve in transfer line out of a well

Figure 4: “fishbone” capillary check valve

chip holder.

h. The detection well must be offset from the other wells by at least 1 cm in order to allow the photosensitive detector to focus only on that well. The photosensitive detector will be an electronic circuit and detection device built by the student team.

III. The chip must fulfill the following operational requirements:

a. Must be able to pass samples of varying concentrations of fluorescein solution for testing without contamination to samples (i.e., raising or lowering concentration due to presence of residual water or fluorescein solution from a previous trial).

b. Must be able to clean chip without removing from chip holder. Once chip is mounted to the bottom half of the chip holder with PDMS, DO NOT clean it with the sonicator as this will cause it to detach.

c. Must be able to perform trials and flushings without backup problems or contamination.

d. Must ensure proper flow to waste well (similar to above).

HINT: Path of least resistance.

e. An operational process should be documented and submitted with the chip design (e.g., “Well1 – pump with sample, stop, test, well1 – flush with DI water, well2 pump…).

IV. Provide sample calculations, footnotes, explanations, etc. as necessary to describe unique features, how feature sizes or shapes based on volume or flow or sealing requirements were determined, etc., in addition to:

a. Well volumes

b. Channel flow lengths

c. Volumes along each flow length

d. Shortest distance from outermost edge of any feature to outside edge of chip

e. Shortest distance from innermost edge of any feature to edge of detection well

f. Any provisions made to ensure proper flow, prevent features from


collapsing, leaking, etc.

HINTS:

Your calculations will have to show conversions from linear dimensions (microns) to volumetric dimensions (microliters). Below are the conversion factor information you should use.

HOW BIG IS A MICRON??? - One thousand microns or micrometers (µm) are in one millimeter (mm).

SO HOW BIG IS A MICROLITER??? - One thousand microliters (µl) are in one milliliter (ml). One milliliter (ml) is also one cubic centimeter (cc or cm3).

HOW ARE CUBIC MICRONS OR CUBIC MICROMETERS CONVERTED TO MICROLITERS, AND VICE VERSA? - The answers to the first two questions can be used to determine this.

There are many useful websites for units conversions such as http://www.unit-conversion.info/

Solidworks Design and Submission Procedures

For the Solidworks submissions, note the following:a. Chip Design Drawings should be fully dimensioned on OSU title block using

Solidworks for both the 1st chip and 2nd chip design submissionsb. Units of dimension for the drawings should be in microns. c. The drawings must be in scale 3:1d. The part file to be turned in for (.SLDPRT) each design should be properly

extruded, with correct dimensions.

Procedure for creating Solidworks file for your designs

You will start the Solidworks drawing of your design using the appropriate Seed File (3-hole or 4-hole).Features of the seed file:

SI units (microns) Grid: Minor Axis -100 microns (100 x 10-6 meters); Major Axis – 1000 microns Snap: 10 microns The boundary of the circular chip, has a diameter of 2 inches = 5.08 cm = 50.8 mm =

50800 micron.


http://www.unit-conversion.info/

http://www.unit-conversion.info/

XY plane, center point, X axis and Y axis are visible. Design of chip holder available by turning on visibility.

**<<Please save your file as “LOC_Sem./Yr._Team_DESIGN#>>**EXAMPLE:

You are taking ENG 1182 Nano in Spring 2013 Semester, and a member of Team B, and you are working on chip design 2:

“LOC_SP13_B_DESIGN2”

Two seed files will be provided on the course DVD under the lecture folder → LOC Solidworks Design → Seed Files. One seed file has a chipholder design which has a total of nine access holes, and the other chipholder design has twelve access holes. You will be asked to develop ONE CHIP DESIGN FOR EACH OF THE TWO CHIPHOLDERS. Refer to Figure 1,2 and 3.

Using Seed File for your designs:

1. Keep all rough design and design requirement and constraint documentation handy for reference.

2. Turn on or turn off visibility on the chip holder sketch as needed. Suppress or unsuppress the chip holder feature (the extrusion) as needed.

3. Open the seed file and extrude the given circle to a thickness of 5mm in the opposite direction of the chip holder extrusion (i.e., do not let them overlap each other).

4. Start a new sketch on the same plane as the top of the extruded 2” circle and draw the detection well first, at the exact center of the chip design.Draw the other wells (waste and staging) according to your approved 1st chip design and the guidelines in this section after you have drawn the detection well. Be sure to allow for enough space between wells as there has to be an adequate seal between each area to avoid leakage, contamination, etc. The chip design must fit the corresponding chip holder design provided in the seed file. Refer to Figure 3.

5. Next draw the channels to connect the staging wells to the detection well and the detection well to the waste well.

1. Be sure to join all entities carefully using constraints and/or Solidworks drawing indicators wherever possible.

2. There should be no breaks where a channel bends, meets a capillary valve, meets a well, or at any other type of junction, i.e., the entire design should be a closed loop.

3. The wafer manufacturing process uses computer-controlled milling machines with a circular bit, which cannot create sharp internal corners. For such features, round the corners with a radius of curvature of at least 200 microns.

4. Even though the channels are very small you should draw them as open channels and not a single line.


6. Now that all the wells and channels have been drawn, it is time to create some capillary valves (optional). These are small well-like areas immediately before a channel joins a well. To prevent unintended movement of the fluids due to capillary flow, capillary valves may be included in the design as described in the previous appendix.

1. Capillary valves may be small and not much greater than 1 mm in diameter, depending on the size of the channels and wells.

2. These need to be centered over the center of each channel while simultaneously being the proper distance from the well.

3. Next, in order to place the edge of the capillary valve 500 microns from the well, the center of the circle representing the capillary valve must be placed a distance of 500 microns plus the radius of the circle from the edge of the well.

4. Next create the circular capillary valve using the point on the line as the edge. 7. Now a great deal of trimming is necessary.

1. Trim the curved areas between the channel walls that intersect the wells and capillary valves. Then delete the small curved segment between the ends of the channel walls, leaving the remainder of the circle intact.

2. Trim the channel wall ends that extend into the capillary valves and wells.3. Trim channel walls that pass completely through capillary valves.4. If a rectangular shape was used for the waste well, the middle piece between

the channel ends for the channel that terminates there should be trimmed.5. Etc… (keep trimming as necessary)

8. Draw your team logo a significant distance from any design features.9. Extrude (CUT into the chip) all the above to create a profile to a depth of 200

microns. Be sure to delete the words “Top Left” as well.

Instructions for Dimensioned Drawing submission (for 1st and 2nd Chip design submissions)

Follow the steps below to make the layout for your hardcopy submission. Refer to Figure 4.

1. If not already open, open your part file for your Design (LOC_SP13_A_DESIGN1.SLDPRT). Select “Drawing” from the upper left-hand new file icon.

2. Click on Model View on the Drawing Toolbar 3. In the property manager, under Part/Assembly to Insert, select the file. Click

next. Under orientation, click “front” under standard views. 4. Under Scale, select custom scale, User Defined, and set to 3:1.5. DO NOT include the chip holder in this layout .6. Under Annotate, choose Smart Dimension to dimension each feature of the

drawing. Place and format appropriately as per the step below.7. Choose the standard OSU title block. Fill out the title block.8. Resize and format the text in the view for proper visibility as necessary.9. Save using the file naming conventions and save as type “Drawing Files

(* .SLDDRW ) ”.

This file should be printed and submitted on the due date given in the Daily Assignment List, along with all other required items (Operational Design,


Calculations, etc. – see the earlier section concerning the “Chip Design and Operational Design” in the Project Description Document for details).

Tips for Dimensioning: o Dimension the chip design in one view: the top view.o Indicate the linear units of measure utilized.o Provide a center line for the chip boundary and dimension the chip boundary.o Dimension the detection well, staging wells, and waste well. Indicate size and

location of these features.o Dimension the channels. Indicate channel width. Indicate channel angles

where appropriate or if channels are diagonal. Indicate channel lengths. o Dimension the capillary check valves. Indicate size and location along the

channel of each of these relative to the well to which they are closest.o Dimension the team logo (it is part of the design!). Do not bother with the

intricacies of the lettering, just indicate overall size and location of the logo as a whole.

o Use notes for repetitive dimensions (if channel widths, well sizes, capillary valve sizes, etc. are the same).

o Save, print, and submit this dimensioned design with the rest of your Chip Design and Operational Design documentation.

NOTE: Dimensions need to be in microns. Use the following procedure:

Dimension a feature in the drawing file and select done Select the dimension by left clicking on it Right click and choose “Edit dimension style” From the pop-up window, under the “Units” tab, under the “units” column, under

“linear”, choose “micron” from the drop-down menu Click done “yes” on the pop up window This should change all dimensions to microns.

Instructions for submission of part files (.SLDPRT files)

Ensure that you turn in the properly extruded part files of both of your designs. The files need to be named appropriately in the manner described earlier. You will send these files to your TA, who will use the files for the manufacture of your

chips.


Figure 1. Generic chip design dimensioned in microns in 3:1 scale.


Samples of drawing submissions

Figure 2: Chip design showing alignment of wells over chipholder access holes


2 Phase GTA Meetings (worth up to 15 points)

You are expected to meet your Graduate Teaching Assistant’s twice during the course of the quarter to get credit for the 2 phase GTA meeting. These meetings need to be scheduled by your teams with the GTA’s at two chronologically different stages of the Lab-on-a-chip project.

GTA Meeting# 1

The first phase meeting should be scheduled to occur in the week before the 1 st chip design is due (check class schedule for due date). This will give you an opportunity to discuss with your GTA the expectations for the assignment: the ‘1st Chip Design’. Teams should make the best use of the opportunity to do well on their initial designs. The GTA’s will also make you aware of the use of the project documentation using the project notebook, which the students have to maintain from the beginning of the semester. Any other concerns regarding the project can also be discussed with the GTA.

GTA Meeting# 2

Check Class Schedule for scheduling date of GTA meeting#2.

During this phase the GTA will assess the project notebooks of each group and provide feedback for further improvement. Time in this meeting will also be devoted toward answering any concerns regarding final testing, oral presentation and final report. The final report draft should be as close as possible to the final product with the exception of the final performance analysis section.

Meeting GradeFor each GTA meeting at least two students from each tem should meet with their respective GTA. In addition, each student within a student team should attend at least one of these meetings.


Nanotechnology Lab TourNanotechnology Lab Tours

The equipment necessary for nanomanufacturing tasks is highly specialized and requires significant training. As such it is not feasible to have everyone work on this equipment for our first-year course. However, to gain a full appreciation for the challenges and opportunities in nanotechnology we have arranged to send small groups to various laboratories around campus to observe some of this specialized equipment. This will be done during one of the lab sessions. To prepare for your Lab Tour, be sure to read and abide by the Lab Tour Summary Requirements listed below. Bring a copy of the Lab Tour Schedule and the Walking Tour Map provided online and take notes in preparation to write and submit a summary memo as described below.

Lab Tour Summary Requirements

Summarize, in approximately one page, in memo format, the following (1 submission per team, refer to Daily Assignment List for the due date):

Use this information for you Lab Tour Summary and retain it for discussion in your Oral Presentation at the end of the quarter:

o Facility touredo Facility locationo Facility head researcher(s) and tour guide(s) (if different)o Type of research performedo Equipment usedo Relevance to nanotechnologyo Relevance to your project. o Application of the facility. State:

types of products or processes it is important for fields of engineering it would it be used in types of materials used (e.g. metals, liquids, polymers, biological

compounds, etc.) current problems being researched challenges remaining in this field whether involved in top-down or bottom-up nanofabrication (if

applicable)


Testing of the Lab-on-a-Chip

Testing 1 st Chip Design

After receiving the LOCs, each team will test their 1st chip for debugging purposes. A member of the instructional team will evaluate the designs and performance according to the lab-on-a-chip requirements. At this operational check, the LOC (including chipholder assembly and detection device) must be calibrated and assembled efficiently. Special attention should be spent on detecting manufacturing defects, leak-proofing if necessary, the calibration flow-stop-detect-flush-repeat operations of the design.

Final Test of the Lab-on-a-Chip

At the end of the class period, a final test of each team's design will take place. You will decide which chip to use for your final test. You will be required to fulfill the flow-stop-detect-flush -repeat operational requirements. In addition, you must be able to successfully determine the concentration of an unknown quantity of fluorescein solution using the reading from your detection device and your calibration formula. The team will be graded on the basis of the final test.


Scoring for the Final System Test

Points will be awarded per the following Final Test Grading Sheet.


Final Report

Draft Final Report

The draft of the final report will be submitted prior to submitting the Final Report. The structural layout of the draft should be similar to that of the Final Report as discussed in the next section. ‘Performance Analysis’ and ‘Summary’ section can be marked as ‘under progress’. The draft being submitted should be as close to the final report as possible with remarks regarding the potential information that will be added eventually in the Final Report.

Final Report Details

This section is designed to help student groups prepare a high-quality, professional report. It contains a description of the contents of each section of the report, and some tips on writing style and presentation of the material that will give the report a more professional appearance. A suggested outline of the report is included on the previous pages.

Description of Section Contents

This section provides some information on what should be included in each part of the team's report, along with some hints or examples that might be helpful in preparing that part of the report. Each part of the report is covered in a separate subsection. Note that your initial lab memos should be fused into the opening sections of the report. Do not copy and paste text from these memos into the report but use them as reference for information.

Cover PageInclude

Project title Team name and number Names of team members Course name and number DATE!!!

Hints Be sure that each time a draft or revision of the report is turned in, the date is changed

on the cover page. Use a design or team logo on the cover page.

Table of ContentsInclude

Number of each part or section Part or section titles Page on which each section begins

Hints The page number for the Table of Contents is "i".


If a section is several pages long, in the Table of Contents, give only the number of the first page of the section.

Look in some published reports or books for examples. From the Microsoft Word menu, use “Insert”, “Reference”, “Index and tables…”, then

click on the “Table of Contents” tab. This is the easiest and neatest way to create this section. You can also use it to update page numbers and heading names in the Table of Contents on command as you make changes to the body of your report.

List of Figures (Drawings)Include

Figure number Figure title (as it appears in the caption on the figure) Page on which the figure is found

Hints Assuming that the Table of Contents is only one page long, the List of Figures is on

page "ii". Look in published reports or books for examples. From the Microsoft Word menu, use “Insert”, “Reference”, “Index and tables…”, then

click on the “Table of Figures” tab. This is the easiest and neatest way to create this section. You can also use it to update page numbers and heading names in the Table of Contents on command as you make changes to the body of your report.

Executive Summary This portion of the report is a very concise rehash of the entire report from the Introduction to the Conclusion. It can be used by a manager in a hurry to get a high-level understanding of the report without having to wade through many pages of detail. It is very brief, yet comprehensive in that it covers the following:

Problem Statement Discussion of the design process Final design descriptions Final design performances Potential improvements.

IntroductionThis part of the report has three main purposes.

Problem Statement: First, it tells the reader exactly what problem is being solved or what piece (or pieces) of equipment will be designed.

Significance of the project: Next, it explains to the reader why this work is important. Organization of the report: Finally, the last paragraph of the introduction gives the

reader a "road map" to the report by describing the organization of the report, stating the sections that follow and a brief statement regarding each section’s content. For example, the last paragraph might contain sentences such as, "Section 2 contains the requirements and constraints the design must meet." or "Description of the preliminary paper design is presented in Section 3.", if section numbers are used. Otherwise, this last paragraph would, in a similar fashion, only list the section titles in place of the section numbers, along with a brief statement about the contents.


NOTE: Very few people read a report from cover to cover. They scan the introduction to see whether the project being described is of interest to them. If it is of interest, they might check the "Organization of the Report" to see which section will provide the information they are seeking.

Requirements, Constraints, and Information NeedsHow does the sponsor, i.e., the person who paid for the project, decide whether the design is acceptable? He or she makes that decision by determining whether the product meets all of the requirements and can be produced within the constraints. This section describes the requirements and constraints that will be used to judge the design. In it team members also identify any additional information they will need to gather in order to design an acceptable product. Examples of a requirement, a constraint, and information need follow. Your report will need to include the following:

Introduction to the section Requirements: specific features that the design must have (e.g., performance

specifications) Constraints: factors that limit design options (e.g., size, budget, material, etc.) Information needs: data that must be collected to evaluate proposed designs (e.g., test or

calibration data)

Example:Suppose a team is to design a child's car seat that converts into a stroller. A requirement might be that the seat be light enough for one person to lift easily. However, a constraint, at least here in Ohio, is the law that any child weighing 45 pounds or less must be in a car seat while traveling in an automobile. The car seat must, therefore, be strong enough to support a 45-pound child, and that certainly could affect the weight of the car seat. As a result, two information needs might be the density and strength of a variety of materials that could be used in a car seat.

1st Chip Design Concepts and AnalysisThe reader will turn to this part of the report to learn about the team's 1 st chip design. Some readers will learn more by reading a written description, some will prefer an illustration, and still others will use both. Thus the team must provide both, a clear written description and illustration of the concept and a stated link between the text and the illustration.

The team reports on the 1st chip design and the actual design progression, in light of the requirements and constraints, and on its 2nd chip design decision. The reader should be able to follow the team's reasoning as it accepts or rejects all or parts of each concept and selects a final design. In addition, the team will describe any refinements to the design (include all relevant revisions to illustrations) and the reasons for them. All calculations (including MATLAB, Excel and paper-based calculations) should be presented. You will include the following:


Introduction to the section Discussion of 1st chip design and its detailed mathematical justifications Discuss how the feedback was incorporated Changes made to the 1st chip design concepts and their revisions in light of the

requirements and constraints Selection of the 2nd chip design Justification of the selection based on requirements and constraints

Hints Think of the written description of as what a team member might say in a telephone

conversation with a potential customer who has asked for a description of the design. The goal is to paint a "mental picture" of the concept.

The concept should be described in detail. Stick to the facts. This is not an advertisement. It is a formal, professional report. Include illustrations of the concept as and when needed. Refer to the illustration in the text so that the reader knows the illustration is available.

Here are some examples of references to an illustration: "The three-wheeled stroller, shown in Figure 3.5, is..." or "One unique feature of this concept is the detachable canopy. (See Figure 3.7.)"

Illustrations should follow the paragraph in which they are first mentioned, if the illustrations occupy less than a full page. If an illustration requires a full page, it should be on the page following the one in which it is first mentioned.

Each illustration (figure) should have a number and a title. For example, “Figure 3.5. Three-Wheeled Stroller/Car Seat Combination in Stroller Mode.”

2nd Chip DesignIf the reader turns to this section first, he or she should find a written description of the 2nd

chip design that provides a clear "mental picture" of the design. That description should be followed by a complete CAD drawing of the design (and complete set of working drawings done in CAD that are detailed enough to allow a lay person to reproduce the team's design). At the end of the description, be sure to tell the reader that the working drawings follow. Include the following:

Introduction to the section Description and comparison of the designs Accompanied CAD/other drawing Summarize the paper and actual design

progressionsi) Show design calculations for at least one feature.ii) Briefly summarize the other features in one of your designs with respect to

volumes, flow rates, flow lengths, assumed maximum sealing pressure, etc., from your 2nd Chip Design documentation

Circuit AnalysisIn this section, teams should include a schematic of the circuit employed and the rationale behind why they that circuit is used. Teams should discuss the advantages and disadvantages afforded by the particular circuit and other possible variations as well as discuss proposed improvements to the circuit. Include the following:


Circuit Schematic Brief working of the circuit Suggestions for using alternative circuits (general) Proposed improvements to the circuit (general)

Performance AnalysisThis section is for the reader who simply wants to know the "bottom line" - what happened in the competition, why it happened, and what the team learned from the design project experience. Introduce the section Tell the reader how your team's system performed (sometimes a table of data with a

discussion of the most important information in the table is effective). Discuss the reasons for the performance of your team’s design Identify the tasks your system performed as expected and mention any problems

encountered. Discuss why the problems occurred and what could be done to solve them. Compare the performance of the two designs, and if one works better than the other,

discuss why.

Fabrication IssuesThis section considers current fabrication process issues and the future of the manufacturing of the device if it was “ramped up” for production or scaled down to the nano. Include the following:

Introductory paragraph Discussion on how prototype was fabricated and type of fabrications methods

employed Discussion on how fabrication process affected chip performance and possible

improvements to this process Discussion on necessary design changes to make chip truly portable, including fully

interfaced detection system Discussion on issues likely to be encountered when scaling the device to the

nanoscale. Discuss issues with respect to manufacture, sensing, fluidics and functionality.

Summary & ConclusionFinally, in a paragraph or two summarize what the team learned from the design project. The "lessons learned" could be related to technical components of the system, communication skills, teamwork, or any other aspect of the course. Include things you will want to remember to do in the future as well as things you want to avoid. You may include the following:

Summary of report contents Suggestions on improvements on the design process and the project as a whole What the team learned from this design project; things team members want to

remember to do in the future, and things they want to do differently.

More Tips


Some tips on report preparation could apply to more than one part of the report: The report is a formal, professional document. It is not advertising copy. Use formal

language. Choose words carefully. Be accurate. Do not exaggerate. The audience for this report is a group of engineers and their managers who must first

decide (on the basis of the written report) whether your design is the best one for their needs. Then, if it is the best, they must be able to build your design using only the information provided from your report.

Don't use first person (I, me, my, we, our) or second person (you, your). Refer to the writers of the report as "the team", "team members", etc. Sometimes, it may be necessary to use passive voice to avoid using first person.

Provide as much detail as is necessary to describe the project but be as concise as possible. Be considerate of the reader. Don't waste his or her time. If a word does not provide new or important information, leave it out.

Use 1 1/2 or double line spacing. Number the pages. The Title of Contents is on page "i", the List of Figures is on page

"ii', and the first section "Introduction" begins on page 1. Use headings and subheadings to help the reader follow the organization of the report

or find the section of interest. Section titles should be the same as those in the Table of Contents. If a numbering system is used for headings and subheadings, it should be the same as the one in the Table of Contents.

Every section, with the exception of the Introduction, should begin with an introductory paragraph that tells the reader what is contained in that section. Remember, the reader may have turned to this section without reading earlier parts of the report.

Tips on Figures Few students have experience putting figures in reports. But in technical reports, figures are often very important. The reader must be able to locate the figure and quickly understand how it is related to the text. Here are some tips on figures.

A figure should have a number and a descriptive title (also called a caption). Some examples follow.

o Figure 1. Multiview drawing of the three-wheeled stroller concept. o Figure 7. Graph showing densities of various stroller construction materials.

The figure number and title in the List of Figures should be the same as the number and title in the body of the report.

Each figure should be described and referenced in the text so that the reader knows to look for the illustration.

A figure should follow the paragraph in which it is first mentioned, if the figure is small, or follow the page on which it is first mentioned, if the figure requires an entire page.

Horizontal figures should be put in the report so that the top of the drawing is on the left and the bottom is on the right. Be careful that the margins are wide enough that the entire figure, including its title, is visible when the report is bound.

Final Report Grading Guidelines

GRADING GUIDELINES


DOCUMENT GRADED: FINAL REPORT TEAM DESIGNATION:

ITEM POSSIBLE POINTS

POINTS EARNED

TABLE OF CONTENTS 5

LIST OF FIGURES & TABLES 5

EXECUTIVE SUMMARY 5

INTRODUCTION 5

MAIN BODY: CONTENT 70

The following non-gray cells represent the breakdown of the 70 points allotted for MAIN BODY: CONTENT. Bolded lines are sections of your report. Non-bolded lines are requirements within that section.

Requirements, Constraints & Information Needs 5

1st Chip Design Concepts and Analysis 10

2nd Chip Design: Description 10

CAD/other Drawings: 2nd Chip Design 5

2nd Chip Design Analysis: 1. Show design calculations for at least one feature; 2. Summary of other features; 3. Justification of 2nd Chip Design

15

Circuit Analysis: Description & Circuit Schematic 5

Performance Analysis 10

Fabrication Issues 10

SUMMARY & CONCLUSIONS 5

OVERALL EFFORT & EFFECTIVENESS 5

TOTAL POINTS 100


Oral Presentation

Towards the end of the semester, each team will give an oral presentation explaining their design process and results. Please refer to the technical communications guide on the EEIC courses website for a general overview on giving oral presentations and a sample presentation.


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