Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Electrical Engineering

First Advisor

Jerald Tunheim


The energy crisis of the 1970's led to a considerable research effort in typical p-n junctions used in solar cells. However, there are several other types of photovoltaic effects worthy of investigation. Two of these effects are of particular interest to this study. One of these is the Dember photovoltaic effect. This effect occurs in the bulk of the semiconductor and arises from the differences in hole and electron mobilities. It requires a semiconductor with metal contacts exposed to light which is nonuniformly distributed. A second type of photovoltaic effect of particular interest is that which occurs in Schottky-barrier devices. These devices are created from direct contact between a metal and a semiconductor. Recently several investigators have reported photovoltaic effects in Schottky-barrier devices and analyzed their behavior. During this investigation a previously unreported photovoltaic effect was observed for stannic oxide (Sn02) single crystals. The primary objective of this investigation is to verify the reproducibility of this effect and to determine the extent to which the above mentioned theories explain the observed photovoltage. Specific objectives of this investigation were: 1. To verify the existence of a photovoltaic effect for stannic oxide single crystals with platinum contacts. 2. To study the effect of the surface potential barrier of stannic oxide on the photovoltaic effect. Variation of the barrier is accomplished by heat treatments in oxygen and nitrogen environments. 3. To understand the role of the metal contacts in the production of the photovoltage.

Library of Congress Subject Headings

Photovoltaic power generation
Solar cells
Stannic oxide



Number of Pages



South Dakota State University


No Copyright - United State