Demonstration of a Micro-Integrated Sub-Millimeter-Wave Pixel

This paper reports on the first demonstration of a micro-integrated pixel operating in the sub-millimeter-wave regime. The pixel consists of a low-noise amplifier realized in InP HEMT, an nIN diode detector, and micromachined horn antenna. The monolithic microwave integrated circuits are attached inside a micromachined silicon waveguide through a novel solder ball process, and a micromachined horn antenna caps the waveguide, which completes the pixel. The form factor is
${>} {\hbox{2500}} \times$
reduction from traditional waveguide block packaging. This size reduction, high level of integration, and integration with a horn antenna enables this technology to be scalable to compact 2-D arrays in the sub-millimeter-wave regime. The pixel noise temperature is measured to be
${\sim} {\hbox {5400}}$
K, which corresponds to sensitivity of an ideal total-power radiometer
$(\Delta { T}_{{{{ M}}}})$
of
${\sim} {\hbox {0.21}}$
K given a 30-ms integration time and bandwidth of 20 GHz.