Biomedical Engineering Reference
In-Depth Information
11.1 Introduction
Microcontact. printing. (μCP). is. a. technique. for. surface. patterning. at. the. micrometer.
and.nanometer.scales..Since.its.invention.by.Kumar.and.Whitesides.in.1993,.it.has.been.
extensively. used. across. diverse. ields. of. science,. engineering,. and. technology.. Search.
of. topic. “microcontact. printing”. at. the. ISI. Web. of. Knowledge. returns. 1261. articles. as. of.
January.1,.2012..The.total.number.of.the.articles.that.involve.this.technique.is.believed.to.be.
considerably.higher.because.alternative.terms.are.commonly.used.for.modiied.versions.of.
μCP..This.chapter.provides.a.brief.overview.of.this.technique,.irst.covering.its.process.and.
principles,.followed.by.a.review.of.its.key.elements.and.applications,.and.ending.with.a.
summary.and.outlook..For.more.information,.the.readers.are.commended.to.read.several.
excellent.review.articles.(Alom.Ruiz.and.Chen.2007;.Kaufmann.and.Ravoo.2010;.Perl.et.al..
2009;.Quist.et.al..2005).
11.2 Process and Principles
μCP.is.well.known.for.its.simple.process,.which.is.to.transfer.a.material.from.one.surface.
to.another.via.physical.contact,.as.schematically.shown.in.Figure.11.1..The.two.structures.
that.carry.the.irst.and.second.surfaces.are.called.stamp.and.substrate,.respectively,.and.
the.material.transferred.is.called.ink..In.a.typical.μCP.process,.an.ink.solution.is.spread.
on. the. stamp. surface. bearing. relief. features. at. the. micro/nanometer. scale.. After. the.
solvent. is. evaporated,. a. thin. layer. of. the. ink. is. left. on. the. stamp. surface,. covering. not.
only.the.protruding.areas,.but.also.the.recessed.areas.and.side.walls.of.the.relief.features..
The.ink.layer.must.be.thin.enough.so.as.not.to.conceal.the.relief.features..The.stamp.is.
then.placed.on.a.substrate.to.allow.physical.contact.between.the.protruding.areas.of.the.
Stamp
Ink
Substrate
Ink on substrate
Figure 11.1
(See companion CD for color igure.)
.Schematic.representation.of.the.microcontact.printing.(μCP).process,.in.
which.ink.is.irst.applied.to.a.stamp.with.relief.features.at.micrometer.or.nanometer.scale;.the.stamp.is.then.
brought.into.physical.contact.with.a.substrate,.resulting.in.transfer.of.the.ink.onto.the.substrate.with.the.same.
2D.pattern.as.the.relief.features.of.the.stamp.
