Research on Monolithic Millimeter-Wave Devices
Abstract
The main thrust of this research has been toward improvement of oscillators for planar microwave and millimeter-wave circuits. There is a need for local oscillators in receivers; for power oscillators in transmitters; and for arrays of both in scanning radar arrays. In all sorts of oscillators, power drops off as frequency increases. Thus we have been seeking new techniques through which power may be increased. For most applications it is desirable to have low noise as well. We have concentrated most of our attention on transferred-electron (including 'Gunn') oscillators. We have developed the concept of multi-domain Gunn diodes. Horizontal devices lend themselves much more readily to the fabrication techniques used in MMICs, resulting in simpler structures. Broadband negative resistance can be obtained, suggesting the possibility of widely tunable voltage-tuned oscillators. We have also studied the design of resonators for planar oscillators. A well-known problem in MMIC technology is the difficulty of making adjustments on a circuit once it has been fabricated. We have investigated ways of making such adjustments. Another component of our work under this grant has concerned a technique for making measurements on working MMICs. Lastly, we have investigated the interesting physical problem of low-frequency oscillations in semi-insulating gallium arsenide. It is found that when a small electric field is applied to this material, low-frequency (audio) current oscillations are observed. (aw)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 25, 1989
- Accession Number
- ADA215771
Entities
People
- Steven E. Schwarz
Organizations
- University of California, Berkeley