US 11,869,986 B2
Vertical deep trench and deep trench island based deep n-type well diode and diode triggered protection device
Umamaheswari Aghoram, Richardson, TX (US); Akram Ali Salman, Plano, TX (US); Binghua Hu, Plano, TX (US); and Alexei Sadovnikov, Sunnyvale, CA (US)
Assigned to Texas Instruments Incorporated, Dallas, TX (US)
Filed by Texas Instruments Incorporated, Dallas, TX (US)
Filed on Aug. 27, 2021, as Appl. No. 17/459,991.
Prior Publication US 2023/0066563 A1, Mar. 2, 2023
Int. Cl. H01L 29/866 (2006.01); H01L 27/02 (2006.01); H01L 29/66 (2006.01)
CPC H01L 29/866 (2013.01) [H01L 27/0255 (2013.01); H01L 29/66106 (2013.01); H01L 27/0259 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a substrate including a semiconductor layer;
a first trench and a second trench in the semiconductor layer;
a doped sheath of a first conductivity type contacting and laterally surrounding the first trench and the second trench, the doped sheath being continuous between the first trench and the second trench, wherein the doped sheath includes a first portion contacting the first trench, a second portion contacting the second trench, and a third portion between the first and second portions, the third portion having a doping concentration greater than the first and second portions;
a doped region of the first conductivity type contacting the first or second portion of the doped sheath providing a cathode of a diode; and
a doped region of a second conductivity type contacting the third portion of the doped sheath between the first trench and the second trench providing an anode of the diode.