Secondary breakdown thermal characterization and improvement of semiconductor devices

Recent work at this Laboratory has indicated that the energy dependence of semiconductor devices with respect to secondary breakdown can be explained on the basis of transient thermal resistance. A new method of measuring transient thermal resistance in the avalanche mode will be described as well as the resultant characteristics. The results indicate that the thermal time constants of transistors is much shorter than heretofore recognized. A similar exercise will be presented for voltage regulator diodes. In addition, a simple technique will be described which significantly increases the thermal time constant of these devices. Similar changes are envisioned for other semiconductor devices.