The Effect of Pressure on the Glass Transition and the Isothermal Compressibility of Amorphous Semiconductors.
Abstract
The glass transition temperature was measured as a function of pressure for the amorphous semiconductors As2S3, Te15Ge2As3, and Cd6Ge3As11 using the transit time of an ultrasonic pulse to detect the glass transition. These measurements were compared to predictions from the free volume theory of the glass transition. In the first two cases, the glass transition temperature first increased and then levelled off with the increasing pressure, as predicted by the free volume theory. The third semiconductor exhibited anomalous behavior: the glass transition temperature first increased with pressure, but at the relatively low pressure of 1.5 kbar the glass transition temperature began to decrease with increasing pressure. The traditional theories of the glass transition temperature are unable to explain this behavior. The isothermal compressibilities of several glasses also were measured and compared with adiabatic compressibilities obtained from ultrasonic measurements. As a general trend for a series of glasses, the compressibilities decrease with increasing glass transition temperature.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1975
- Bibcode:
- 1975PhDT........12J
- Keywords:
-
- Physics: Condensed Matter;
- Amorphous Semiconductors;
- Compressibility;
- Glass;
- Isothermal Processes;
- Pressure Effects;
- Adiabatic Conditions;
- Glass Transition Temperature;
- Ultrasonics;
- Solid-State Physics