Minority Carrier Generation Studies in MOS Capacitors on N-Type Silicon

The pulsed capacitance technique was utilized to determine minority carrier generation rates in MOS capacitors. The addition of HCl , Cl 2 , CCl 4 , or C 2 HCl 3 to oxygen during thermal oxidation was effective in gettering trapping centers in the silicon and resulted in lifetimes greater than 150 µsec. Higher halide concentrations and high oxidation temperatures improve the gettering process. The capacitance-time plot showed that the generation rate in long‐lifetime structures was proportional to the volume of carrier‐depleted silicon and that the generation of carriers on the surface was very small, e.g., S ≈ 10− 2 cm/sec.