Nonvolatile semiconductor memory device and manufacturing method of the same
US5972750A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 1998 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Feb 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.