Photoelectric Properties of Ionically Bombarded Silicon

Because of the importance that barriers have come to assume in the general field of semiconductors the authors have been urged to publish results of their early experiments in this field. These experiments were undertaken in the course of a search for semiconductive material suitable for use as point contact rectifiers. Before March 19411 one of the writers discovered a well-defined barrier having a high degree of photovoltaic response. The barrier was found only in melts of some lots of commercially available high-purity silicon. This barrier showed a high photovoltaic sensitivity to radiation from incandescent lamps. The existence of this natural barrier was first observed in rods cut from melts for resistivity measurements. These rods showed a high degree of photovoltaic response, were found to have a high thermoelectric coefficient, and had good rectifying properties. 1 The fact that one end of the rod developed a negative potential when illuminated or heated and that when supplied with a negative potential showed low resistance to current flow across the barrier led to the terminology of n-type 802