Trench MIS device and method for manufacturing trench MIS device
First Claim
Patent Images
1. A trench MIS device comprising:
- a drain region;
a base region disposed on the drain region, the base region having a channel face;
a source region disposed on the base region, the source region having a source end face, the source end face being continuous with the channel face;
a gate insulator disposed continuously along the channel face and the source end face;
a gate electrode disposed opposite to the channel face through the gate insulator; and
a cavity portion provided in the drain region below the gate electrode, the cavity portion being opposite to the gate electrode.
1 Assignment
0 Petitions
Accused Products
Abstract
A trench MIS device includes a drain region, a base region disposed on the drain region, the base region having a channel face, a source region disposed on the base region, the source region having a source end face, the source end face being continuous with the channel face, a gate insulator disposed along the channel face and the source end face, a gate electrode disposed opposite to the channel face through the gate insulator, and a cavity portion provided in the drain region, the cavity portion being opposite to the gate electrode.
-
Citations
20 Claims
-
1. A trench MIS device comprising:
-
a drain region;
a base region disposed on the drain region, the base region having a channel face;
a source region disposed on the base region, the source region having a source end face, the source end face being continuous with the channel face;
a gate insulator disposed continuously along the channel face and the source end face;
a gate electrode disposed opposite to the channel face through the gate insulator; and
a cavity portion provided in the drain region below the gate electrode, the cavity portion being opposite to the gate electrode. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method for manufacturing a trench MIS device including:
-
preparing a semiconductor substrate on which a drain region, a base region, and a source region are formed in order;
forming a trench extending from the source region to the drain region via the base region, the trench having a trench sidewall and a trench bottom;
forming a gate insulator on the trench sidewall and the trench bottom;
forming a polycrystalline silicon film on the gate insulator, the polycrystalline silicon film being doped with a plurality of dapants; and
forming a cavity portion in a lower portion of the trench and a gate electrode derived from the polycrystalline silicon film in an upper portion of the trench by a diffusion of a plurality of silicon atoms in the polycrystalline silicon film, the diffusion being caused by a hydrogen annealing of the polycrystalline silicon film. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method for manufacturing a trench MIS device including:
-
forming a drain region on a semiconductor substrate;
forming a cave in the drain region;
diffusing a plurality of silicon atoms inside a cave sidewall of the cave by a hydrogen annealing of the cave so as to fill an upper portion of the cave with the silicon atoms to form a cavity portion in the drain region;
forming a trench above the cavity portion in the drain region, the trench being not penetrating to the cavity portion;
forming a gate insulator on a trench sidewall of the trench; and
forming a gate electrode on the gate insulator by filling the trench with an electrically conductive material. - View Dependent Claims (18, 19, 20)
-
Specification