Microcrystalline Piezoresistive Polysilicon Film Obtained by Aluminum Induced Crystallization

Polycrystalline silicon films with relatively large grain size were obtained by aluminum-induced crystallization (AIC) of amorphous silicon films. Unlike conventional deposition techniques which require high temperatures, crystallization was accomplished by annealing at temperatures ranging from 475degC to 550degC, for 90 minutes. Polysilicon films thus obtained exhibited piezoresistive properties. XRD characterization of the film verified good polycrystalline structure. Electrical characterization of the film verified high conductivity polysilicon film thus eliminating further doping steps. The fabrication technique described here would be suitable for attaining polycrystalline silicon films on substrates or structures with stringent thermal budget constraints.