Semiconductor device manufacturing: process – Making regenerative-type switching device – Altering electrical characteristic
Reexamination Certificate
2005-05-02
2010-12-14
Wilczewski, Mary (Department: 2822)
Semiconductor device manufacturing: process
Making regenerative-type switching device
Altering electrical characteristic
C257SE21388, C257SE21054, C257SE21066
Reexamination Certificate
active
07851274
ABSTRACT:
A structure and method for a silicon carbide (SiC) gate turn-off (GTO) thyristor device operable to provide an increased turn-off gain comprises a cathode region, a drift region having an upper portion and a lower portion, wherein the drift region overlies the cathode region, a gate region overlying the drift region, an anode region overlying the gate, and at least one ohmic contact positioned on each of the gate region, anode region, and cathode region, wherein the upper portion of the drift region, the gate region, and the anode region have a free carrier lifetime and mobility lower than a comparable SiC GTO thyristor for providing the device with an increased turn-off gain, wherein the free carrier lifetime is approximately 10 nanoseconds. The reduced free carrier lifetime and mobility are affected by altering the growth conditions, such as temperature under which epitaxy occurs.
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Adams William V.
Anderson Lawrence E
The United States of America as represented by the Secretary of
Wilczewski Mary
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