Micropackaging for Mm-Wave Circuits.

In microwave and millimeter wave circuit applications the issue of RF packaging is becoming an important subject to address due to the lack of appropriate packaging configurations for high frequency circuit design. Several years back, experts in the field of device and component development began to realize that packaging of such components was progressing at much slower rate than the devices themselves. As a result, many problems observed in device and component performance at these frequencies are being attributed, after diagnostic testing, to the package in which they are housed. Typical problems associated with circuit packages, especially above X band, include resonances due to the large physical geometry surrounding these circuits, crosstalk caused by parasitic radiation from neighboring circuits, arid unwanted excitations that result in power leakage in the form of substrate modes. Many of these issues can be addressed bv integrating the package with the circuit monolithically, by on-wafer packaging, which implies that the package is fabricated as part of the circuitry and is designed to meet performance specifications. With state of the art advances in semiconductor processing techniques, silicon micromachining offers what conventional means have not been able to provide packages which conform to the circuit geometry, provide on-wafer electromagnetic and environmental protection, require much less space and provide superior mechanical, thermal and electrical performance.