THE USE OF ION-IMPLANTATION FOR MICROMACHINING GAAS FOR SENSOR APPLICATIONS

In this paper we report the results of GaAs micromachining using ion implantation for sensor applications. According to various implantation parameters and subsequent annealing conditions different sensor types can be realised. A new design for single chip capacitive pressure sensors is described and the structures are realised based on the selective etching of locally damaged layer created by ion implantation. Using low dose nitrogen implantation into n-GaAs, mechanically stable GaAs cantilevers are produced after a pulse anodic selective etching. The buried GaAs1-xNy (y<x<1) layer, introduced by the high dose nitrogen implantation, is wet chemically removable with high etching selectivity against the GaAs. The fabrication of a GaAs cantilever demonstrates the possibility to realise accelerometers using this method.