dip-pen nanolithography (1)

Rajiv Gandhi Institute of Technology

Department Of Mechanical Engineering

Sarath Krishna. M.ES7 Mechanical

Roll No: 45

INTRODUCTION Invented by Alois Senefelder in

Germany in 1798 Fundamentally new printing

technology Mechanical Plano graphic process in

which the printing and non-printing areas of the plate are all at the same level

Dip-Pen Nanolithography

DPN is a unique modification of atomic force microscope (AFM) instrumentation.

High-resolution patterning capabilities for a number of molecular and biomolecular ‘inks’ on a variety of substrate types such as metals, semiconductors, and monolayer functionalized surfaces.

Atomic Force Microscope (AFM)

Techniques in AFM DC mode AFM AC mode AFM

Characteristics of AFM Works by measuring local properties -

such as height, optical absorption, or magnetism - with a probe or "tip" placed very close to the sample.

The small probe-sample separation makes it possible to take measurements over a small area

Measurement of topography with a force probe

AFM operates by measuring attractive or repulsive forces between a tip and the sample.

Concept of AFM In principle, AFM resembles the record

player as well as the stylus profilometer. However, AFM incorporates a number of refinements that enable it to achieve atomic-scale resolution:

Sensitive detection Flexible cantilevers Sharp tips High-resolution tip-sample positioning Force feedback

Types of AFM tips

Normal tip (3 µm tall) supertip (3 µm tall) Ultralever (3 µm tall).

Working of DPN

Illustration of molecular deposit of DPN tip

Images of dots and lines of magnetic nanoparticles created using DPN

AFM image showing lattice-resolved monolayer of octadecanethiol patterned on gold via DPN.

A)Ultra-high resolution pattern of mercaptohexadecanoic acid on atomically flat gold

surface.B) DPN generated multi-component nanostructure with

two aligned alkanethiol patterns.

Applications of DPN

Limitations Slow process Cannot be used in Vaccum

A Multipen Plotter for Parallel Patterning

Schematic of two-pen DPN plotter

Conclusion Dozens of research groups worldwide

are working on DPN applications to develop even better techniques

The tDPN technique, an improvement to DPN could be used to produce features too small to be formed with light-based lithography, and as a nanoscale soldering iron for repairing circuitry on semiconductor chips

Thank you