NONVOLATILE SEMICONDUCTOR STORAGE DEVICE AND ITS MANUFACTURE

Title:

NONVOLATILE SEMICONDUCTOR STORAGE DEVICE AND ITS MANUFACTURE

Document Type and Number:

Japanese Patent JPH11154713

Kind Code:

A

Abstract:

To enable separate work on the source side and drain side of a floating gate.

Firstly, control gate electrodes 16 are formed by RIE(reactive ion etching) by using mask materials 17 as masks. Then resists 22 are formed to cover the drain sides of the electrodes 16 by leaving the mask materials 17 as they are. After the resists 22 are formed, the source sides of the electrodes 16 are worked by RIE by using the mask materials 17 and resists 22 as masks. At the time of working the source sides of the electrodes 16, the working condition is optimized so that the source sides are formed in reversely tapered shapes. It is possible to perform ion implantation thereafter to form source diffusion layers by using the mask materials 17 and resists 22 as masks. The drain sides of the electrodes 16 are also worked in the same way.

Inventors:

MORI SEIICHI

Application Number:

JP32094997A

Publication Date:

June 08, 1999

Filing Date:

November 21, 1997

Export Citation:

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Assignee:

TOSHIBA CORP

International Classes:

H01L21/8247; H01L27/115; H01L29/788; H01L29/792; (IPC1-7): H01L21/8247; H01L29/788; H01L29/792; H01L27/115

Attorney, Agent or Firm:

Takehiko Suzue (6 outside)

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