Development of millimeter-wave two-dimensional imaging array

A millimeter- wave two-dimensional imaging array has been developed for dia gnostics of magnetically confined plasmas. It is applied to the plug cell o f the GAMMA 10 tandem mirror, and measures time evolution of radial and axi al line-density and electron cyclotron emission (ECE) profiles in one plasm a shot. The monolithic-type GaAs Schottky diode detector having an antenna and built-in amplifier on a GaAs substrate is newly fabricated using monoli thic microwave integrated circuit (MMIC) technology. This novel detector is developed to attain high frequency response up to submillimeter-wave regio n and wideband heterodyne characteristics, and is expected to be applied to ECE imaging in a large helical device. The response of the detector is com pared with that of the hybrid-type detector using beam-lead Schottky barrie r diodes. The first experimental result of the ECE measurement is reported using a heterodyne radiometer with the MMIC detector. (C) 1999 American Ins titute of Physics. [S0034-6748(99)67701-2].