Behaviour of logic gates fabricated on Si∕SiGe MODFET technology

The behaviour of two fabricated logic gates using n-type Si/SiGe MODFETs is reported. S-parameter measurements show that the voltage separation between states at 20 GHz is 15 dB for the NAND gate and 8 dB for the NOR gate. The measured DC levels of the outputs allow the possibility of cascading the gates for use in more complex circuits.