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Water-soluble sacrificial layers for surface micromachining.

Vincent Linder·Byron D Gates·Declan Ryan·Babak A Parviz·George M Whitesides
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Abstract

This manuscript describes the use of water-soluble polymers for use as sacrificial layers in surface micromachining. Water-soluble polymers have two attractive characteristics for this application: 1) They can be deposited conveniently by spin-coating, and the solvent removed at a low temperature (95-150 degrees C), and 2) the resulting layer can be dissolved in water; no corrosive reagents or organic solvents are required. This technique is therefore compatible with a number of fragile materials, such as organic polymers, metal oxides and metals-materials that might be damaged during typical surface micromachining processes. The carboxylic acid groups of one polymer-poly(acrylic acid) (PAA)-can be transformed by reversible ion-exchange from water-soluble (Na+ counterion) to water-insoluble (Ca2+ counterion) forms. The use of PAA and dextran polymers as sacrificial materials is a useful technique for the fabrication of microstructures: Examples include metallic structures formed by the electrodeposition of nickel, and freestanding, polymeric structures formed by photolithography.

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Acrylic ResinsCalciumChemistry, OrganicDextransElectrochemistryIonsNanotechnologyNickelOxidesPolymersSolubilitySolventsSurface PropertiesTemperatureWaterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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BibTeXRIS

Vincent Linder, Byron D Gates, Declan Ryan, Babak A Parviz, George M Whitesides. 2005. Water-soluble sacrificial layers for surface micromachining.. https://doi.org/10.1002/smll.200400159

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