| Autor: |
E. S. Hellman, Kevin L. Lear, P. M. Pitner, Byung-Gook Park, James S. Harris, D. Thomas, Thierry Weil, E. Wolak |
| Rok vydání: |
1988 |
| Předmět: |
|
| Zdroj: |
SPIE Proceedings. |
| ISSN: |
0277-786X |
| Popis: |
The effect of impurities placed in double barrier resonant tunneling diodes, on the current voltage characteristics of the devices was experimentally determined. Four different double barrier structures were grown by Molecular Beam Epitaxy with n-type, p-type, undoped and highly compensated doping in the center of the well. Two additional samples were grown with and without n-type doping in the barriers. Resonant tunneling devices of various sizes were fabricated, and measured at 77 K. Systematic shifts in the peak current voltage and peak to valley ratio were observed for the devices with different dopant profiles. The shifts in peak current position for the devices with varied well doping are correctly predicted by a modified ballistic model which includes the effects of band bending due to ionized impurities in the well. The doped devices showed a systematic decrease in the peak to valley ratio which is not predicted by the ballistic model. A scattering assisted tunneling mechanism which increases the valley current is proposed. The magnitude of the calculated increase in valley current due to elastic scattering by impurities which were intentionally placed in the well, is consistent with the observed lowering of the peak to valley ratio. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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