The effect of an evaporated thick aluminium paper on electrical proper
ties of multicrystalline and gold contaminated FZ monocrystalline sili
con wafers was investigated. By means of minority carrier diffusion le
ngth measurements and Deep Level Transient Spectroscopy, it was deduce
d that the material improvements observed after annealing at 900 degre
es C are due to gettering of metallic impurities in the Al-Si alloyed
layer.