Patent · US Expired

Nonvolatile semiconductor memory device and manufacturing method of the same

US5972750A · kind A · utility

6Cited by
2References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 2, 1998
Grant dateOct 26, 1999
Priority date
Expiry dateFeb 2, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/90

Abstract

There are disclosed a nonvolatile semiconductor memory device, which is capable of maintaining a high capacitance ratio even when a memory cell is formed in a micronized size without increasing the number of manufacturing steps, and its manufacturing method. In a flash memory having buried diffusion layer type cells, a source region and drain regions and are formed in self alignment with a polycrystalline film pattern which has a polycrystalline silicon film having projecting and recessing parts in its upper surface.

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