Novel SiC device technology featuring enhancement and depletion mode transistors

Silicon Carbide (SiC) has enjoyed rapid success in discrete device development primarily due to the availability of single crystal wafers and the similarities which exist with present day silicon technologies. Some of the devices which have been fabricated in SiC include the MOSFET, MESFET, thyristor, JFET, and UMOS. Additionally some devices, such as MOSFETs and MESFETs, have been utilized in integrated form to demonstrate digital and analog circuitry. However, the MOS devices used in integrated circuits have all been of one type, either enhancement or depletion. It is the purpose of the present study to investigate an integrated circuit technology which provides both enhancement and depletion mode NMOS transistors. This type of circuit technology is desirable for high-density circuit integration schemes since it consumes less area than an all enhancement or depletion mode design.