Patent · US Expired

Vertical MOSFET

US6414347B1 · kind B1 · utility

17Cited by
4References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 9, 2001
Grant dateJul 2, 2002
Priority date
Expiry dateFeb 9, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/2255
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An improved process for making a vertical MOSFET structure comprising: A method of forming a semiconductor memory cell array structure comprising: providing a vertical MOSFET DRAM cell structure having a deposited gate conductor layer planarized to a top surface of a trench top oxide on the overlying silicon substrate; forming a recess in the gate conductor layer below the top surface of the silicon substrate; implanting N-type dopant species through the recess at an angle to form doping pockets in the array P-well; depositing an oxide layer into the recess and etching said oxide layer to form spacers on sidewalls of the recess; depositing a gate conductor material into said recess and planarizing said gate conductor to said top surface of the trench top oxide.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.