Patent · US Expired

Method of manufacturing non-volatile semiconductor memory device

US4988635A · kind A · utility

22Cited by
4References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 1989
Grant dateJan 29, 1991
Priority date
Expiry dateMay 24, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B41/35

Abstract

A memory cell of 1 bit is constituted by 1 selecting transistor and 1 memory transistor in an EEPROM. One of the source-drain regions is commonly used by the selecting transistor and the memory transistor. The commonly used source-drain region is manufactured through the following steps. First, a gate electrode of the transistor is formed. An oxide film is deposited on the entire surface. A resist is applied thereon and is etched back to expose a surface of the oxide film on the gate electrode. Thereafter, the oxide films deposited on the side surfaces of the gate electrode are removed to form opening portions. Impurities are implanted to the silicon substrate utilizing the opening portions.

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