High power semiconductor device with integral on-state voltage detection structure

Claim 2

A high power semiconductor device with integral on-state voltage detection structure comprising: a semiconductor drift region of a first conductivity type, having an upper portion and a lower portion; a base region of a second conductivity type formed in the upper portion of the drift region; a source region of the first conductivity type formed in the base region, wherein a first channel is defined between a lateral boundary of the source region and a lateral boundary of the base region; a first gate dielectric covering the first channel; a first gate electrode covering the first gate dielectric over the first channel; a source electrode coupled to the source region and electrically isolated from the first gate electrode; a detector region of the second conductivity type formed in the upper portion of the drift region and separated from the base region by a second channel, wherein the detector region forms a detector diode with the drift region, the detector diode being a diode other than a zener diode; and a detector electrode coupled to the detector region, wherein the detector electrode is electrically isolated from the source electrode and the gate electrode.

Claim 3

A high power semiconductor device with integral on-state voltage detection structure comprising: a semiconductor drift region of a first conductivity type, having an upper portion and a lower portion; a base region of a second conductivity type formed in the upper portion of the drift region; a source region of the first conductivity type formed in the base region,, wherein a first channel is defined between a lateral boundary of the source region and a lateral boundary of the base region; a first gate oxide covering the first channel; a first gate electrode covering the first gate oxide over the first channel; a source electrode coupled to the source region and electrically isolated from the first gate electrode; a detector region of the second conductivity type formed in the upper portion of the drift region and separate from the base region by a second channel, wherein the detector region forms a detector diode with the drift region, the detector diode being a diode other than a zener diode; a second gate oxide covering the second channel; a second gate electrode covering the second gate oxide over the second channel, wherein the second channel is of an opposite conductivity type as the first channel; and a detector electrode coupled to the detector region, wherein the detector electrode is electrically isolated from the source electrode and the gate electrode.

Claim 4

A high power semiconductor device with integral on-state voltage detection structure comprising: a semiconductor drift region of a first conductivity type, having an upper portion and a lower portion; a base region of a second conductivity type formed in the upper portion of the drift region; a source region of the first conductivity type formed in the base region,, wherein a first channel is defined between a lateral boundary of the source region and a lateral boundary of the base region; a first gate oxide covering the first channel; a first gate electrode covering the first gate oxide over the first channel; a source electrode coupled to the source region and electrically isolated from the first gate electrode; a detector region of the second conductivity type formed in the upper portion of the drift region and separate from the base region by a second channel, wherein the detector region forms a detector diode with the drift region, the detector diode being a diode other than a zener diode; a second gate oxide covering the second channel; a second gate electrode covering the second gate oxide over the second channel, wherein the second channel is of an opposite conductivity type as the first channel; and a detector electrode coupled to the detector region, wherein the detector electrode is electrically isolated from the source electrode and the gate electrode.

Claim 5

The high power semiconductor device of claim 2 wherein the first gate oxide has a thickness in the range of 0.03-0.15 micrometers and the second gate oxide has a thickness in the range of 0.3-0.5 micrometers.

Claim 6

The high power semiconductor device of claim 1 wherein an external signal applied to the detector electrode forward biases the detector diode when the drift region potential is below a predetermined voltage and the detector diode becomes reverse biased when the drift region potential is greater than the predetermined voltage.

Claim 7

The high power semiconductor of claim 2 wherein the second gate electrode is electrically coupled to the source electrode so that the second channel becomes conductive when a drift region potential is greater than a predetermined threshold voltage.

Claim 8

The high power semiconductor of claim 1 wherein the first conductivity is n-type and the second conductivity is p-type.

Claim 9

The high power semiconductor of claim 1 wherein a doping distribution and a junction depth of the base region is substantially the same as doping concentration and junction depth of the detector region.

Claim 10

A saturation detecting semiconductor device comprising: a semiconductor drift region of a first conductivity type having an upper surface; a semiconductor switch formed in the upper surface and having a first gate oxide adjacent the upper surface; a nonzener saturation detection diode formed in the upper surface and spaced from the semiconductor switch by at least a channel region, wherein the nonzener saturation detector diode and the semiconductor switch are electrically coupled to the drift region; and a saturation detector electrode coupled to the nonzener saturation detector diode.

Claim 11

A saturation detecting semiconductor device comprising: a semiconductor drift region of a first conductivity type having an upper surface; a semiconductor switch formed in the upper surface and having a first gate oxide adjacent the upper surface; a nonzener saturation detection diode formed in the upper surface and spaced from the semiconductor switch by at least a channel region, wherein the nonzener saturation detector diode and the semiconductor switch are electrically coupled to the drift region; and a saturation detector electrode coupled to the nonzener saturation detector diode.

Claim 12

The saturation detecting semiconductor device of claim 8 further comprising a second gate oxide formed over the channel region; and a gate electrode covering the second gate oxide over the channel region.

Claim 13

The saturation detecting semiconductor device of claim 9 wherein thickness of the second gate oxide over the channel region is selected so that the channel region becomes conductive when a potential of the upper surface of the drift region is above a predetermined voltage, wherein the predetermined voltage is greater than about 30 volts and less than a breakdown voltage of the semiconductor switch.

Claim 14

The saturation detecting semiconductor device of claim 8 wherein the semiconductor switch comprises a MOSFET transistor.

Claim 15

The saturation detecting semiconductor device of claim 8 wherein the semiconductor switch comprises an IGBT.