公开(公告)号：US11239317B2

公开(公告)日：2022-02-01

申请号：US16807230

申请日：2020-03-03

Applicant: Kioxia Corporation

Inventor： Shoichi Watanabe ,  Mitsuhiro Noguchi

IPC: H01L29/08 ,  H01L27/092 ,  H01L27/11573 ,  H01L29/34 ,  H01L21/8238 ,  H01L21/8234 ,  H01L27/11582 ,  H01L27/11551 ,  H01L27/1157 ,  H01L27/11524 ,  H01L27/11578 ,  G11C16/30

Abstract: According to a certain embodiment, the nonvolatile semiconductor memory device includes: a first conductivity-type semiconductor substrate including a crushed layer on a back side surface thereof; a memory cell array disposed on a front side surface of the semiconductor substrate opposite to the crushed layer; and a first conductivity-type high voltage transistor HVP disposed on the semiconductor substrate and including a first conductivity-type channel, configured to supply a high voltage to the memory cell array. The first conductivity-type high voltage transistor includes: a well region NW disposed on the surface of the semiconductor substrate and having a second conductivity type; a source region and a drain region disposed in the well region; and a first conductivity-type first high concentration layer WT2 disposed between the crushed layer of the semiconductor substrate and the well region and having a higher concentration than an impurity concentration of the semiconductor substrate.