Accomplishments

Fabricated and demonstrated the first double-implanted MOS (DMOS) power transistors in SiC (1996). These devices exhibited a blocking voltage of 760 V, a new record for SiC MOSFETs. Recent improvements have increased the blocking voltage to 880 V.
Fabricated the first lateral power MOSFETs in SiC (1997). These devices set a new record for blocking voltage at 2.6 kV.
Invented and fabricated the first Optimized UMOS ACCUFETs with novel features to protect the trench oxide and reduce on-resistance (1998). Blocking voltages of 1400 V and specific on-resistance of 15.7 mOhm-cm² are obtained on a 10 痠 drift region, and the figure-of-merit V_B²/R_on is 125 MW/cm², 25x higher than the theoretical limit for silicon power MOSFETs.
Fabricated SiC Schottky barrier diodes with blocking voltages of 4.9 kV (1999), the highest value yet reported.

Fabricated the first C-band SiC Static Induction Transistors, with f_t of 7 GHz. (1999).
Demonstrated the first IMPATT diode microwave oscillators in SiC (2000).

Originated the concept for the one-transistor nonvolatile RAM cell (U.S. Patent #5,465,249, issued November 7, 1995).
Fabricated and demonstrated the first nonvolatile RAM cells in SiC (1991).
Demonstrated storage times of over 100 years at room temperature with no power applied (based on over four years of continuous storage).

Fabricated and demonstrated the first monolithic digital integrated circuits in SiC (1993). These NMOS ICs included NAND, NOR, XNOR, binary counter, and half adder circuits, and were operational at temperatures up to 300 C.
Fabricated the first SiC planar MESFET ICs using vanadium implant isolation (1995).
Fabricated the first p-well CMOS ICs in SiC (Sept. 1996). These included NAND, NOR, XNOR, half adder, and ring oscillator circuits. A second processing run in March 1997 produced the first SiC CMOS circuits to operate on a single 5 V power supply from room temperature to 300 C.

Fabricated and demonstrated the first CCD's in SiC (1995). The experimental devices were 32-bit double-polysilicon-overlapping-gate buried-channel CCDs.

Conducted measurements of interface state density on SiC as a function of bandgap energy using both the hi-lo CV technique and the ac conductance-frequency technique at elevated temperatures.
Reduced the interface state density on p-type SiC to 1.5x10¹¹ eV^-2 cm^-2, the lowest value yet reported. Reduced the fixed oxide charge density to 8.5x10¹¹ cm^-2.
Demonstrated that aluminum dopant does not contribute to the formation of interface states in SiC MOS devices.
Performed the first measurements of interface state and fixed charge density on 4H-SiC.
Performed the first measurements of interface state and fixed charge density on the "a-axis" surfaces of 6H-SiC.

Conducted the first measurements of high-field drift velocity of electrons in 4H-SiC and the second measurements of electron drift velocity in 6H-SiC.

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