US 11,894,458 B2
Lateral double-diffused metal oxide semiconductor field effect transistor
Jiaxing Wei, Wuxi (CN); Qichao Wang, Wuxi (CN); Kui Xiao, Wuxi (CN); Dejin Wang, Wuxi (CN); Li Lu, Wuxi (CN); Ling Yang, Wuxi (CN); Ran Ye, Wuxi (CN); Siyang Liu, Wuxi (CN); Weifeng Sun, Wuxi (CN); and Longxing Shi, Wuxi (CN)
Assigned to SOUTHEAST UNIVERSITY, Jiangsu (CN); and CSMC TECHNOLOGIES FAB2 CO., LTD., Wuxi (CN)
Appl. No. 17/762,206
Filed by SOUTHEAST UNIVERSITY, Jiangsu (CN); and CSMC TECHNOLOGIES FAB2 CO., LTD., Wuxi (CN)
PCT Filed Sep. 25, 2020, PCT No. PCT/CN2020/117572
§ 371(c)(1), (2) Date Oct. 7, 2022,
PCT Pub. No. WO2021/120766, PCT Pub. Date Jun. 24, 2021.
Claims priority of application No. 201911310548.5 (CN), filed on Dec. 18, 2019.
Prior Publication US 2023/0019004 A1, Jan. 19, 2023
Int. Cl. H01L 29/78 (2006.01)
CPC H01L 29/7825 (2013.01) 15 Claims
OG exemplary drawing
 
1. A lateral double-diffused metal oxide semiconductor field effect transistor, comprising:
a source region of a first conductivity type;
a drain region of the first conductivity type;
a drift region of the first conductivity type;
a bulk region of a second conductivity type;
a field oxide layer located on a surface of the drift region;
a trench gate comprising a lower part inside a trench and an upper part outside the trench, a length of the lower part in a width direction of a conducting channel being less than that of the upper part in the width direction of the conducting channel, and the lower part extending into the bulk region and having a depth less than that of the bulk region; and
an insulation structure arranged between the drain region and the trench gate and extending downwards into the drift region, a depth of the insulation structure being less than that of the drift region, a depth of the insulation structure in the drift region being greater than that of the field oxide layer in the drift region, a length of the insulation structure in the width direction of the conducting channel being less than that of the drift region in the width direction of the conducting channel, the field oxide layers being formed on surfaces of two sides of the insulation structure in the width direction of the conducting channel, and the upper part extending onto the field oxide layer; the first conductivity type and the second conductivity type being opposite conductivity types.