A FORMING STUDY OF POINT-CONTACT TUNNEL DIODES
Abstract
The factors involved in the forming of point contact tunnel diodes by the application of brief electrical overloads are studied. As a test of the theory, a diode fabricated from N-doped germanium and an aluminum cat whisker is used through the paper. After a brief review of the thermal and electrical conductivities of heavily doped germanium at elevated temperatures, an evaluation is made of the critical breakdown voltage (the applied voltage below which no forming of any type occurs), assuming constant electrical and temperature-dependent thermal conductivity. Junction effects are taken into account by considering the 'cold' diode characteristic in predicting a voltage below which current is limited by junction effects and above which spreading resistance dominates. For voltages higher than he critical voltage, it is assumed that a eutectic region is formed under the point, extending into the body of the semiconductor. A heat flow pattern is computed, and, on the basis of this, two different types of diode structures emerge. In a typical example, solid-state diffusion is found to be negligible.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1963
- Accession Number
- AD0407917
Entities
People
- H. J. Lory
Organizations
- Johns Hopkins University