OXIDE SEMICONDUCTOR MATERIALS AND DEVICE RESEARCH

A stockpile of material was prepared for use later in making sample diodes. This material consists entirely of dense uniform ceramic rutile. A study was made of the rectifying properties of diodes made with gold contacts as opposed to silver contacts. The rectifying contacts made with gold were found to be superior. The fabrication process for forming the oxide layers on rutile rectifying barriers was modified by reducing the temperature and extending the time of preparation. Preliminary results indicate that higher reverse breakdown voltages were obtained through this modification, but this advantage was offset by an increase in the forward resisttance. Preparations have been made for measuring the admittance of rutile barriers. A sample holder with built-in coupling network for use with a Wayne-Kerr bridge has been constructed. An auxiliary network has been designed to apply dc bias to the diodes being tested. Measurements of the Seebeck coefficient of semiconducting polycrystalline rutile were made during the past period. The equipment is described and preliminary measurements are outlined. Author