US 12,080,806 B2
Fast recovery diode and manufacturing method thereof
Xiuguang Xiao, Shenzhen (CN); and Wei Zhang, Shenzhen (CN)
Assigned to BYD SEMICONDUCTOR COMPANY LIMITED, Shenzhen (CN)
Appl. No. 17/296,045
Filed by BYD SEMICONDUCTOR COMPANY LIMITED, Shenzhen (CN)
PCT Filed Nov. 15, 2019, PCT No. PCT/CN2019/118786
§ 371(c)(1), (2) Date Nov. 12, 2021,
PCT Pub. No. WO2020/103770, PCT Pub. Date May 28, 2020.
Claims priority of application No. 201811388533.6 (CN), filed on Nov. 21, 2018.
Prior Publication US 2022/0059707 A1, Feb. 24, 2022
Int. Cl. H01L 29/00 (2006.01); H01L 29/66 (2006.01); H01L 29/861 (2006.01)
CPC H01L 29/8611 (2013.01) [H01L 29/66136 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A fast recovery diode, comprising:
a cell region;
a main junction region arranged around the cell region; and
a termination region arranged around the main junction region,
wherein a main junction doping region in the main junction region has a doping concentration lower than that of an active region in the cell region, and the doping concentration of the main junction doping region decreases along a direction from inside to outside via a number of gradient doping regions of the main junction doping region,
wherein the number of gradient doping regions are sequentially arranged from inside to outside, each having a doping concentration, and the doping concentration of any gradient doping region is higher than that of an adjacent gradient doping region along the direction from inside to outside,
wherein each of the number of gradient doping regions is an annular continuous region surrounding the cell region, the doping concentration of each gradient doping region is independent from any other doping region by being doped independently and is lower than that of the active region, and the annular gradient doping regions are formed next to each other to form the main junction doping region.