Based upon p-type strongly compensated electronic grade monocrystalline Czochralski silicon, an attempts was made to discover whether self interstitials had a direct or an indirect role in light and dark induced degradation. Many studies were carried out on light-induced degradation phenomenon due to the formation of boron-oxygen complexes under light exposure. Some of them compare as-cut wafers and wafers which were treated by phosphorus diffusion. They showed that the light-induced degradation phenomenon was reduced when samples were phosphorus-diffused. This effect was explained by self-interstitial injection in the bulk during the phosphorus diffusion, but the role of these self-interstitials on light-induced degradation phenomenon was not yet well defined. Here, investigations on the degradation kinetic were made in as-cut wafers, in phosphorus-diffused wafers and in wafers which were annealed in the same conditions used for the phosphorus diffusion. Comparisons of the results permitted the pinpointing of the role of self-interstitials in light-induced degradation phenomena. It seemed that the presence of a high self interstitial concentration reduced the formation of BsO2i complexes responsible for the first faster degradation.

Investigation of Self Interstitial Influences in Light and Dark Induced Degradation in p-Type Compensated Silicon. V.M.T.Yen, D.Barakel, I.Périchaud, O.Palais: Energy Procedia, 2012, 27, 76-81