Optical - Microwave Interactions in Semiconductor Devices.
Abstract
Theoretical calculations were carried out to explain the observed results of optical switching of GaAs IMPATT diode oscillators. In the previous experiments it was found that depending on the diode's bias condition, the frequency of oscillation, and the intensity of illumination, the IMPATT microwave output power could be either enhanced or reduced. This problem was treated by carrying out a theoretical calculation of the property of IMPATT diode under optical illumination. It was determined that the most significant contribution of optical illumination in an IMPATT diode is the drastic increase in reverse saturation current Is. Using small signal analysis we obtained an expression for the total impedance of the IMPATT diode under optical illumination. It was found that optical illumination causes the shifting of the negative resistance and reactance versus frequency curves. This in turn causes the oscillation frequency to vary and the output power to drop in general. However, the cavity tuning yields a strongly frequency dependent threshold for the diode. Therefore under certain circumstance optical illumination can actually trigger the IMPATT diode into oscillation also. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1978
- Accession Number
- ADA053806
Entities
People
- Huan-wun Yen
- Michael K. Barnoski
Organizations
- HRL Laboratories