公开(公告)号：US10763105B2

公开(公告)日：2020-09-01

申请号：US16234303

申请日：2018-12-27

Applicant: INSTITUTE OF MICROELECTRONICS, CHINESE ACADEMY OF SCIENCES

Inventor： Xinyu Liu ,  Yidan Tang ,  Shengkai Wang ,  Yun Bai ,  Chengyue Yang

IPC: H01L21/02 ,  H01L29/78

Abstract: A method of manufacturing a grooved-gate MOSFET device based on a two-step microwave plasma oxidation, including: etching a grooved gate, and oxidizing silicon carbide on a surface of the grooved gate to silicon dioxide by microwave plasma to form a grooved-gate oxide layer, the step of forming the grooved-gate oxide layer including: placing a silicon carbide substrate subjected to the grooved gate etching in a microwave plasma generating device; introducing a first oxygen-containing gas, heating generated oxygen plasma to a first temperature at a first heating rate, and performing low-temperature plasma oxidation at the first temperature and a first pressure; heating the oxygen plasma to a second temperature at a second heating rate, introducing a second oxygen-containing gas, and performing high-temperature plasma oxidation at the second temperature and a second pressure until a predetermined thickness of silicon dioxide is formed; stopping introduction of the oxygen-containing gas, and completing the reaction.

公开(公告)号：US20210074807A1

公开(公告)日：2021-03-11

申请号：US17041393

申请日：2018-09-12

Applicant: Institute of Microelectronics, Chinese Academy of Sciences

Inventor： Yidan Tang ,  Xinyu Liu ,  Yun Bai ,  Shengxu Dong ,  Chengyue Yang

IPC: H01L29/06 ,  H01L29/45 ,  H01L29/872 ,  H01L29/47 ,  H01L29/40

Abstract: The present disclosure discloses a semiconductor device and a preparation method thereof. The semiconductor device includes: an N+ substrate, a plurality of openings opening toward a back surface formed in the N+ substrate; an N− epitaxial layer formed on the N+ substrate, the N− epitaxial layer including: an active area epitaxial layer including a plurality of P++ area rings and a plurality of groove structures, wherein single groove structure is formed on single P++ area ring; a terminal area epitaxial layer including an N+ field stop ring and a plurality of P+ guard rings; a Schottky contact formed on the active area epitaxial layer, a passivation layer formed on the terminal area epitaxial layer, and ohmic contacts formed on the back surface of the N+ substrate and in the plurality of openings.

公开(公告)号：US10680067B2

公开(公告)日：2020-06-09

申请号：US15759102

申请日：2015-09-10

Applicant: INSTITUTE OF MICROELECTRONICS, CHINESE ACADEMY OF SCIENCES ,  ZHUZHOU CRRC TIMES ELECTRIC CO., LTD.

Inventor： Yidan Tang ,  Huajun Shen ,  Yun Bai ,  Jingtao Zhou ,  Chengyue Yang ,  Xinyu Liu ,  Chengzhan Li ,  Guoyou Liu

IPC: H01L21/336 ,  H01L29/66 ,  H01L29/16 ,  H01L29/06 ,  H01L29/78 ,  H01L21/02 ,  H01L21/04 ,  H01L21/324 ,  H01L27/092 ,  H01L29/08 ,  H01L29/417 ,  H01L29/423

Abstract: The present disclosure discloses a self-aligned silicon carbide MOSFET device with an optimized P+ region and a manufacturing method thereof. The self-aligned silicon carbide MOSFET device is formed by a plurality of silicon carbide MOSFET device cells connected in parallel, and these silicon carbide MOSFET device cells are arranged evenly. The silicon carbide MOSFET device cell comprises two source electrodes, one gate electrode, one gate oxide layer, two N+ source regions, two P+ contact regions, two P wells, one N− drift layer, one buffer layer, one N+ substrate, one drain electrode and one isolation dielectric layer. By optimizing the P+ region, the present disclosure forms a good source ohmic contact, reduces the on-resistance, and also shorts the source electrode and the P well to prevent the parasitic transistor effect of the parasitic NPN and PiN, which may take both conduction characteristics and the breakdown characteristics of the device into consideration, and may be applied to a high voltage, high frequency silicon carbide MOSFET device. The self-aligned manufacturing method used in the present disclosure simplifies the process, controls a size of a channel accurately, and may produce a lateral and vertical power MOSFET.

公开(公告)号：US11508809B2

公开(公告)日：2022-11-22

申请号：US17041393

申请日：2018-09-12

Applicant: Institute of Microelectronics, Chinese Academy of Sciences

Inventor： Yidan Tang ,  Xinyu Liu ,  Yun Bai ,  Shengxu Dong ,  Chengyue Yang

IPC: H01L29/06 ,  H01L29/47 ,  H01L29/872 ,  H01L29/40 ,  H01L29/45

Abstract: The present disclosure discloses a semiconductor device and a preparation method thereof. The semiconductor device includes: an N+ substrate, a plurality of openings opening toward a back surface formed in the N+ substrate; an N− epitaxial layer formed on the N+ substrate, the N− epitaxial layer including: an active area epitaxial layer including a plurality of P++ area rings and a plurality of groove structures, wherein single groove structure is formed on single P++ area ring; a terminal area epitaxial layer including an N+ field stop ring and a plurality of P+ guard rings; a Schottky contact formed on the active area epitaxial layer, a passivation layer formed on the terminal area epitaxial layer, and ohmic contacts formed on the back surface of the N+ substrate and in the plurality of openings.

公开(公告)号：US10734199B2

公开(公告)日：2020-08-04

申请号：US16224435

申请日：2018-12-18

Applicant: INSTITUTE OF MICROELECTRONICS, CHINESE ACADEMY OF SCIENCES

Inventor： Xinyu Liu ,  Yidan Tang ,  Shengkai Wang ,  Yun Bai ,  Chengyue Yang

IPC: H01J37/32 ,  C23C8/10 ,  H01L21/02

Abstract: A microwave plasma generating device for plasma oxidation of SiC, comprising an outer cavity and a plurality of micro-hole/micro-nano-structured double-coupling resonant cavities disposed in the outer cavity. Each resonant cavity includes a cylindrical cavity. A micro-hole array formed by a plurality of micro-holes is uniformly distributed on a peripheral wall of the cylindrical cavity, a diameter of each of the micro-holes is an odd multiple of wavelength, and an inner wall of the cylindrical cavity has a metal micro-nano structure, the metal micro-nano structure has a periodic dimension of λ/n, where λ is wavelength of an incident wave, and n is refractive index of material of the resonant cavity. The outer cavity is provided with an gas inlet for conveying an oxygen-containing gas into the outer cavity, and the oxygen-containing gas forms an oxygen plasma around the resonant cavities for oxidizing SiC; a stage is disposed under the resonant cavities.

公开(公告)号：US10699898B2

公开(公告)日：2020-06-30

申请号：US16287902

申请日：2019-02-27

Applicant: INSTITUTE OF MICROELECTRONICS, CHINESE ACADEMY OF SCIENCES

Inventor： Xinyu Liu ,  Shengkai Wang ,  Yun Bai ,  Yidan Tang ,  Zhonglin Han ,  Xiaoli Tian ,  Hong Chen ,  Chengyue Yang

IPC: H01L21/02 ,  H01J37/32

Abstract: A method for oxidizing a silicon carbide based on microwave plasma at an AC voltage, including: step one, providing a silicon carbide substrate, and placing the silicon carbide substrate in a microwave plasma generating device; step two, introducing oxygen-containing gas to generate oxygen plasma at an AC voltage; step three, controlling movements of oxygen ions and electrons in the oxygen plasma by the AC voltage to generate an oxide layer having a predetermined thickness on the silicon carbide substrate, wherein when a voltage of the silicon carbide substrate is negative, the oxygen ions move close to an interface and perform an oxidation reaction with the silicon carbide, and when the voltage of the silicon carbide substrate is positive, the electrons move close to the interface and perform a reduction reaction with the silicon carbide, removing carbon residue; step four, stopping the introduction of oxygen-containing gas and the reaction completely.