Etched structure geometry

Etching is an old and very well-established technology, in principle. But, several details of etching mechanisms are not completely known. New challenges arise from new demands of geometries of microlithographically etched structures and from new types of materials. 

Institute of Technology (Reese et al., 2003). Using optical lithography to etch away photolithographic resists on stainless steel foils, french pens were designed with a rectangular geometry of 6 p in depfh, 30 p in width with 30 p sidewalls at the tips. To add structural support, the features anterior to the tip were expanded out so that the width of the sidewalls increased to 120 p with a trench width set at 90 p. 

A monocrystalline chip 1 of HgCdTe is polished and a mask 2 is patterned according to the desired geometry of the array The chip is chemically etched by HCL and HNO3 in the areas not covered by the mask, so as to form a projecting structure. 

During the last years, a growing interest in the creation of micro- and nanoelectronic devices by use of the swift heavy ion track technology in a combination with carbon nanotubes (CNTs) is observed in several research centers worldwide. The CNTs were grown in etched ion tracks in Si02 layers on Si. For this purpose, Ni-catalyst nanoclusters were electrochemically deposited within the ion tracks. The geometry of the obtained nanostructures has been analyzed. Structure features of CNTs obtained by themial chemical vapor deposition have been investigated. 

Figure 13.6. Diamond cantilever structures of different geometries made by dry etching an HOD film. It is seen that piezoresistors are integrated at the suspension point 419].

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