Silicon-carbide trench gate MOSFETs
First Claim
1. An apparatus comprising:
- a silicon-carbide (SiC) substrate of a first conductivity type;
a drift region of the first conductivity type disposed in the SiC substrate on a front side of the SiC substrate;
a drain region disposed on a back side of the SiC substrate;
a shielding body region of a second conductivity type disposed in the drift region;
a source region of the first conductivity type disposed in the shielding body region;
a gate trench disposed in the SiC substrate, the gate trench having a depth that is greater than a depth of the source region and less than a depth of the shielding body region;
a gate dielectric disposed on a sidewall of the gate trench and a bottom surface of the gate trench, the gate dielectric on the sidewall of the gate trench defining a first interface with the shielding body region, the gate dielectric on the bottom surface of the gate trench defining a second interface with the shielding body region;
a gate electrode disposed on the gate dielectric; and
a lateral channel region of the first conductivity type, the lateral channel region being disposed in the shielding body region along the second interface.
9 Assignments
0 Petitions
Accused Products
Abstract
In a general aspect, an apparatus can include a semiconductor substrate, a drift region disposed in the semiconductor substrate; a body region disposed in the drift region and a source region disposed in the body region. The apparatus can also include a gate trench disposed in the semiconductor substrate. The apparatus can further include a gate dielectric disposed on a sidewall and a bottom surface of the gate trench, the gate dielectric on the sidewall defining a first interface with the body region and the gate dielectric on the bottom surface defining a second interface with the body region. The apparatus can still further include a gate electrode disposed on the gate dielectric and a lateral channel region disposed in the body region, the lateral channel region being defined along the second interface.
-
Citations
19 Claims
-
1. An apparatus comprising:
-
a silicon-carbide (SiC) substrate of a first conductivity type; a drift region of the first conductivity type disposed in the SiC substrate on a front side of the SiC substrate; a drain region disposed on a back side of the SiC substrate; a shielding body region of a second conductivity type disposed in the drift region; a source region of the first conductivity type disposed in the shielding body region; a gate trench disposed in the SiC substrate, the gate trench having a depth that is greater than a depth of the source region and less than a depth of the shielding body region; a gate dielectric disposed on a sidewall of the gate trench and a bottom surface of the gate trench, the gate dielectric on the sidewall of the gate trench defining a first interface with the shielding body region, the gate dielectric on the bottom surface of the gate trench defining a second interface with the shielding body region; a gate electrode disposed on the gate dielectric; and a lateral channel region of the first conductivity type, the lateral channel region being disposed in the shielding body region along the second interface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 19)
-
-
12. An apparatus comprising:
-
a silicon-carbide (SiC) substrate of a first conductivity type; a drift region of the first conductivity type disposed in the SiC substrate on a front side of the SiC substrate; a drain region disposed on a back side of the SiC substrate; a shielding body region of a second conductivity type disposed in the drift region; a source region of the first conductivity type disposed in the shielding body region; a threshold control region of the second conductivity type disposed in the shielding body region, the threshold control region being disposed below the source region and having a depth that is less than a depth of the shielding body region; a gate trench disposed in the SiC substrate, the gate trench having a depth that is greater than a depth of the threshold control region and less than a depth of the shielding body region; a gate dielectric disposed on a sidewall of the gate trench and a bottom surface of the gate trench, the gate dielectric on the sidewall of the trench defining an interface with the threshold control region and a first interface with the drift region, the gate dielectric on the bottom surface of the trench defining a second interface with the drift region; a gate electrode disposed on the gate dielectric; and a lateral channel region of the first conductivity type, the lateral channel region being disposed in the shielding body region along the second interface, the sidewall of the gate trench being spaced a first distance from the shielding body region, the first distance being less than or equal to a second distance, the second distance being a lateral width from a vertical edge of the shielding body region to a vertical edge of a zero-bias depletion region of the apparatus. - View Dependent Claims (13, 14)
-
-
15. An apparatus comprising:
-
a silicon carbide (SiC) substrate of a first conductivity type; a drift region of the first conductivity type disposed in the SiC substrate on a front side of the SiC substrate; a drain region disposed on a back side of the SiC substrate; a shielding body region of a second conductivity type disposed in the drift region; a source region of the first conductivity type disposed in the shielding body region; a gate trench disposed in the SiC substrate, the gate trench having a depth that is greater than a depth of the source region and less than a depth of the shielding body region; a gate dielectric disposed on a sidewall of the gate trench and a bottom surface of the gate trench, the gate dielectric on the sidewall of the gate trench defining a first interface with the shielding body region, the gate dielectric on the bottom surface of the gate trench defining a second interface with the shielding body region, the sidewall of the gate trench defining an angle of greater than 90 degrees with the bottom surface of the gate trench; a gate electrode disposed on the gate dielectric; and a lateral channel region of the first conductivity type, the lateral channel region being disposed in the shielding body region along the second interface. - View Dependent Claims (16, 17, 18)
-
Specification