Excimer laser crystallization of amorphous silicon on metal coated glass substrates

The influence of metal coatings of glass substrates on the laser crystallization process of amorphous silicon is investigated. Three different metals were chosen: Mo, Al and Ni. Amorphous silicon was deposited on top of the metal and crystallized using a XeCl excimer laser. Auger electron spectroscopy and Raman measurements show that in case of Ni and Al an intermixing with the polycrystalline silicon (poly-Si) due to the laser treatment occurs resulting in a rough film. In the case of Al, regions of highly Al doped poly-Si were observed. On the other hand laser crystallization of a-Si:H on Mo coated glass does not result in an intermixing. The average grain size varies with the laser fluence. In the super lateral growth regime grains of size up to 1 mum can be fabricated. These large grains show a preferential surface orientation along the {1 1 1} direction. (C) 2002 Elsevier Science B.V. All rights reserved.