Fabrication of Tapered Bio Mimetic Cilia Using Bulk Lithography and Ceramic Mold

Abstract

This paper presents fabrication of tapered, high aspect ratio bio mimetic cilia from Nickel-polydimethyl siloxane (Ni-PDMS) composite by using bulk lithography technique and ceramic molding. Many research groups suggested fabrication of bio mimetic cilia using various techniques which are based on soft lithography and VLSI techniques. Recently a novel single layer micro fabrication technique known as ‘bulk lithography’ which uses an unconstrained photopolymer has been reported by co-authors. This technique is used to fabricate a polymer cilia pattern (an array of photopolymerised inverted cone profile) and using this pattern a ceramic green body is fabricated by slip casting technique. An aqueous suspension containing sub micron size alumina is used to cast ceramic green body. After casting this cilia pattern makes negative impression of tapered holes on green ceramic body. During sintering of green ceramic body the polymer burns off resulting in ceramic mould with tapered holes imprinted on it. This mold retains shape of a tapered hole though it shrinks in size after sintering. This mold is used further to cast Ni-PDMS composite in the form of cilia structures.