Diode structures with controlled injection efficiency for fast switching
First Claim
1. A semiconductor device disposed in a semiconductor substrate comprising:
- a second semiconductor layer of a second conductivity type located at a top portion of said semiconductor substrate; and
a first semiconductor layer of a first conductivity type located below said second semiconductor layer;
wherein the first semiconductor layer further comprises an injection efficiency controlling buffer layer of the first conductivity type disposed immediately below said second semiconductor layer of the second conductivity type, said injection efficiency controlling buffer layer being located in a top portion of the first semiconductor layer,wherein the first semiconductor layer further comprises a drift region of the first conductivity type located below the injection efficiency controlling buffer layer wherein the injection efficiency controlling buffer layer is more heavily doped than the drift layer such that the injection efficiency of said second semiconductor layer is controlled, and wherein the first semiconductor layer and the second semiconductor layer comprise two parts of a diode, one part being an anode and the other part being a cathode.
1 Assignment
0 Petitions
Accused Products
Abstract
This invention discloses a semiconductor device disposed in a semiconductor substrate. The semiconductor device includes a first semiconductor layer of a first conductivity type on a first major surface. The semiconductor device further includes a second semiconductor layer of a second conductivity type on a second major surface opposite the first major surface. The semiconductor device further includes an injection efficiency controlling buffer layer of a first conductivity type disposed immediately below the second semiconductor layer to control the injection efficiency of the second semiconductor layer.
-
Citations
23 Claims
-
1. A semiconductor device disposed in a semiconductor substrate comprising:
-
a second semiconductor layer of a second conductivity type located at a top portion of said semiconductor substrate; and a first semiconductor layer of a first conductivity type located below said second semiconductor layer; wherein the first semiconductor layer further comprises an injection efficiency controlling buffer layer of the first conductivity type disposed immediately below said second semiconductor layer of the second conductivity type, said injection efficiency controlling buffer layer being located in a top portion of the first semiconductor layer, wherein the first semiconductor layer further comprises a drift region of the first conductivity type located below the injection efficiency controlling buffer layer wherein the injection efficiency controlling buffer layer is more heavily doped than the drift layer such that the injection efficiency of said second semiconductor layer is controlled, and wherein the first semiconductor layer and the second semiconductor layer comprise two parts of a diode, one part being an anode and the other part being a cathode. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A method for manufacturing a semiconductor device disposed in a semiconductor substrate comprising:
-
forming a first semiconductor layer of a first conductivity type in said semiconductor substrate; and forming a second semiconductor layer of a second conductivity type at a top portion of said semiconductor substrate, over the first semiconductor layer, wherein said forming a first semiconductor layer further comprises forming an injection efficiency controlling buffer layer of the first conductivity type immediately below said second semiconductor layer of the second conductivity type and forming a drift layer of the first conductivity type below the injection efficiency controlling buffer layer such that the injection efficiency controlling buffer layer is more heavily doped than the drift region to control an injection efficiency of said second semiconductor layer, wherein the first semiconductor layer and the second semiconductor layer comprise two parts of a diode, with one part being an anode and the other part being a cathode. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23)
-
Specification