Fast switching diode with low leakage current
View Patent ↗A fast switching diode includes an n− layer having an upper surface and a lower surface and a first edge and a second edge, the second edge provided on an opposing side of the first edge. A converted region is provided proximate the upper surface of the n− layer. The converted region includes platinum and has a first depth. The converted region has a platinum concentration that is substantially greater than an n-type dopant concentration in the converted region. First and second n+ regions are provided proximate the first and second edges of the n− layer, respectively, and extend from the upper surface of the n− layer to second and third depths, respectively. Each of the second and third depths is greater than the first depth to reduce leakage current. A first electrode is provided proximate the upper surface of the n− layer. A second electrode is provided proximate the lower surface of the n− layer.
1. A fast recovery diode, comprising:
a first n-type layer having a first conductivity, the first n-type layer having an upper surface and a lower surface and a first edge and a second edge, the second edge provided on an opposing side of the first edge;
a first p-type region provided proximate the upper surface of the first n-type layer and extending substantially the entire upper surface of the first n-type layer, the first p-type region having a first depth, the first p-type region including platinum;
a first n-type region provided proximate the first edge of the first n-type layer and abutting an end of the first p-type region, the first n-type region extending from the upper surface of the first n-type layer to a second depth, the second depth being greater than the first depth to reduce leakage current;
a first electrode provided proximate the upper surface of the first n-type layer; and
a second electrode provided proximate the lower surface of the first n-type layer.
2. The diode of claim 1 , further comprising:
a second n-type layer having a second conductivity provided between the first n-type layer and the second electrode, wherein the second n-type layer has a higher conductivity than the first n-type layer,
wherein the first and second n-type layers define a substrate, the first n-type layer has less conductivity than the second n-type layer, and
wherein the first n-type region is a channel stopper.
3. The diode of claim 1 , wherein the first p-type region is a converted region formed within the first n-type layer by providing the first n-type layer with platinum.
4. The diode of claim 3 , wherein the first p-type region has a platinum concentration level that is substantially greater than that of a n-type dopant concentration level of the first n-type layer.
5. The diode of claim 3 , wherein an upper surface of the first p-type region has a platinum concentration level that is at least two times that of a n-type dopant concentration level on the upper surface of the first p-type region.
6. The diode of claim 3 , wherein an upper surface of the first p-type region has a platinum concentration level that is at least three times that of a n-type dopant concentration level on the upper surface of the first p-type region.
7. The diode of claim 1 , wherein the second depth of the first n-type region is 15 microns or greater.
8. The diode of claim 1 wherein the second depth of the first n-type region is 20 microns or greater.
9. The diode of claim 1 , further comprising:
a second p-type region provided proximate the upper surface of the first n-type layer and in contact with the first electrode; and
a second n-type region provided proximate the second edge of the first n-type layer and extending from the upper surface of the first n-type layer to a third depth, the third depth being greater than the first depth to reduce leakage current;
wherein the first p-type region is a converted region provided to increase a switching speed of the diode, the second p-type region is an emitter region, the first electrode is an anode, the second electrode is a cathode, the first and second n-type regions are channel stoppers.
10. A fast switching diode, comprising:
an n− layer having an upper surface and a lower surface and a first edge and a second edge, the second edge provided on an opposing side of the first edge;
a converted region provided proximate the upper surface of the n− layer and extending substantially from the first edge to the second edge, the converted region including platinum and having a first depth, the converted region having a platinum concentration that is substantially greater than an n-type dopant concentration in the converted region;
first and second n+ regions provided proximate the first and second edges of the n− layer, respectively, the first and second n+ regions being provided within the converted region and extending from the upper surface of the n− layer to second and third depths, respectively, the second and third depths each being greater than the first depth to reduce leakage current;
a first electrode provided proximate the upper surface of the n− layer; and
a second electrode provided proximate the lower surface of the n− layer.
11. The diode of claim 10 , further comprising:
an n+ layer provided between the n− layer and the second electrode,
wherein the first and second n+ regions are channel stoppers, and
wherein the second and third depths are 15 microns or greater.
12. The diode of claim 11 , wherein the second and third depths each is 20 microns or greater.
13. The diode of claim 11 , wherein the second and third depths each is 25 microns or greater.