Title:
HIGH-SPEED FLYBACK DIODE-INTEGRATED SILICON CARBIDE SPLIT GATE MOSFET AND PREPARATION METHOD
Document Type and Number:
WIPO Patent Application WO/2023/142393
Kind Code:
A1
Abstract:
The present invention relates to the technical field of power semiconductor devices, and relates to a high-speed flyback diode-integrated silicon carbide split gate MOSFET and a preparation method therefor. The MOSFET of the present invention uses the design of a split gate so as to reduce the switch loss of a device. In order to prevent the problem of gate oxide reliability caused by the structure of the split gate, a P-type buried layer is added to reduce the electric field intensity of a gate oxide layer at the edge of polycrystalline silicon. Furthermore, an N-type current conduction layer is added to introduce current from a channel to a drift region of the device. In addition, in order to reduce the conduction voltage drop of a silicon carbide MOSFET parasitic body diode and introduce a unipolar conduction mode, a high-speed flyback diode based on a MOS structure is introduced on the other side of a cell of the MOSFET. Compared with traditional practices, the high-speed flyback diode of the present invention uses surface smearing of the P-type buried layer to form a channel area, i.e., the conduction voltage drop of the high-speed flyback diode is reduced without adding additional versions.
Inventors:
GU HANG (CN)
GAO WEI (CN)
DAI MAOZHOU (CN)
GAO WEI (CN)
DAI MAOZHOU (CN)
Application Number:
PCT/CN2022/106142
Publication Date:
August 03, 2023
Filing Date:
July 16, 2022
Export Citation:
Assignee:
NOVUS SEMICONDUCTORS CO LTD (CN)
International Classes:
H01L29/423; H01L21/28; H01L21/336; H01L21/82; H01L27/06; H01L29/06; H01L29/10; H01L29/78
Foreign References:
| CN114122123A | 2022-03-01 | |||
| CN113130627A | 2021-07-16 | |||
| CN110473917A | 2019-11-19 | |||
| CN108346692A | 2018-07-31 | |||
| US20080308838A1 | 2008-12-18 |
Attorney, Agent or Firm:
CHENGDU RUIDAO PATENT AGENCY (GENERAL PARTNERSHIP) (CN)
Download PDF: