Trenched MOS Gate Controlled Rectifier
AssigneeDiodes Incorporated
InventorsPeter Hugh Blair, Lee Spencer Riley
Life of this patent
Estimating the term…
Abstract
A trenched MOS gate controlled rectifier has an asymmetric trench structure between the active area of active trenches and the termination area of termination trenches. The asymmetric trench structure has a gate electrode on one side of the trench to turn on and off the channel of the MOS structure effectively and a field plate structure on the other side with field dielectric sufficiently thick in order to sustain the high electric field during the reverse bias condition.
Claims21
A semiconductor chip, comprising
- a trench structure, comprising;
- a first trench with opening at a top surface of the chip having sidewalls of a epitaxial semiconductor material;
- a second trench in the middle of the first trench, with opening at near the top surface, having sidewalls of dielectric material, and filled with a field plate;
- and
- the field plate having adjacent gate electrode on one side and free of adjacent gate electrode on the opposite side.
A process of making an asymmetric trench in a semiconductor chip, comprising:
- lining sidewalls of a trench in the chip with a dielectric layer;
- covering the dielectric layer on one sidewall and exposing the dielectric layer on the opposite sidewall;
- and
- removing portion of the exposed dielectric layer.
A semiconductor device, comprising:
- a semiconductor chip having an asymmetric trench structure, comprising:
- a first trench having semiconductor sidewalls;
- a second trench having dielectric sidewalls and disposed inside the first trench;
- and
- a third trench having dielectric sidewalls and disposed inside the first trench and outside the second trench.
Dependencies are inferred from the claim text.