Investigation of formation conditions of thermal donors-I and -II in oxygen-containing n-type silicon within the temperature range 400 to 800°C

Thermally induced donors in Czochralski-grown dislocation-free phosphorus-doped n-Si crystals of different oxygen and carbon contents are investigated by different techniques. Hall effect within the temperature range 20 to 450 K, dependences of piezoresistance and Hall coefficient on uniaxial elastic deformation within the mechanical stress range 0 to 15000 kp/cm2 and electron paramagnetic resonance are used. The dependence of the donor behaviour on both, the heat treatment and the starting materials is studied. It is established that thermally induced donors at 450°C differ from donors, which are induced at 650°C, if not in their chemical composition then, at any rate, in their structure and, possibly, in their surrounding.