Possibility of silicon monolithic millimeterwave integrated circuits

Previous work on high-resistivity silicon suggests that microstrip line dielectric losses cease to be significant above 30 GHz. Silicon-germanium heterojunction bipolar transistors now provide a well-behaved three-terminal device capable of operating at microwave frequencies. The tradeoffs available to operate this device at millimeter-wave frequencies are discussed, and calculations indicate that the fabrication of silicon monolithic millimeter-wave integrated circuits is a genuine possibility.<>