Abstract
The variations of the surface conductance, surface recombination velocity and field effect in terms of surface potential are measured on thin single crystal silicon wafers. Surface potential is varied in several gaseous ambients by so-called Brattain-Bardeen ambient cycle. From surface conductance measurement, values of surface potential are deduced and from the photoconductance measurement, surface recombination velocity is obtained. By combining these measurements, the surface recombination velocity is plotted as a function of the surface potential. It is found that the surface recombination velocity for p-type silicon sample of 112 ohm cm varies over about a factor of ten in a 0.6 V range of the surface potential. As the sample was exposed repeatedly to the ambient cycle, the surface potential shifted gradually to positive direction and the variation of surface conductance with ambient was smaller than that on the freshly etched sample. The fast decay time of the field effect was several milliseconds and sensitive to illumination.
