Dependence of temperature-dependent hole concentration on position of p-type wafer within polycrystalline Si ingot for solar cells

摘要

The temperature dependence of the hole concentration p(T) was measured in p-type wafers sliced out of polycrystalline Si ingots used for solar cells. The dependence of p(T) on the position in the ingot was investigated, and it was confirmed that p(T) in the bottom part of the ingot was disobedient to the Fermi-Dirac distribution function. In the top part of the ingot, on the other hand, the densities and energy levels of several impurities could be determined by the evaluation method proposed at our laboratory, since p(T) was obedient to the Fermi-Dirac distribution function.