On-wafer probing at 140 GHz (MMICs)

This paper describes some research work that will be carried out with the support of the SERC over the next three years. The work is part of a larger grant which involves the production of MMICs at 140 GHz. The author´s contribution to this research is to provide the measurement facility for on-wafer probing at these frequencies. Two problems arise at the out-set, which are the lack of commercial network analysers and the high attenuation of metallic waveguides at 140 GHz. The paper describes an alternative to a network analyser which the author has already used for measurements in the range 70-110 GHz (Collier and D´Souza, 1991). Also the paper discusses a technique which avoids the problems of metallic waveguide. Finally some comments are made about probes for these frequencies.<>