Heterojunction compound semiconductor device

摘要

A heterojunction semiconductor device comprises a minimum of four compound semiconductor layers on a semiconductor substrate (31), alternate layers (32) and (34) from the substrate not containing Al and the layers (33) and (35) alternating therewith containing A1. A first set of electrodes is formed on the second compounds semiconductor layer for serving as terminals of a first field effect transistor and a second set of electrodes formed on the fourth compound semiconductor layer serve as terminals of a second field effect transistor.