Reuseable solid aluminium metaphosphate silicon dopant - for controlled doping in single temp furnace

摘要

At least part of the surface of an Si wafer is contacted with P2O2 vapour from a solid aluminum metaphosphate source at high enough temp. to permit the reaction of the vapour with (part of) the Si surface and for long enough to cause diffusion of P. The Si (p-type semiconductor) element and aluminum metaphosphate source may be placed close together, but not touching, in a furnace at 750-1200 degrees C pref. provided with Ar carrier gas.