Semiconductor device and method of manufacturing the same

• US 6,803,622 B2
• Filed: 10/22/2002
• Issued: 10/12/2004
• Est. Priority Date: 08/26/2002
• Status: Expired due to Term

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Shiozawa, Junichi, Matsuno, Koichi
• Primary Examiner(s): WOJCIECHOWICZ, EDWARD JOSEPH
• Application Number:
  US10/274,871
• Publication Number:
  US 20040036107A1
• Time in Patent Office: 721 Days
• Field of Search: 257/314, 257/506, 257/508, 257/509, 257/512
• US Class Current: 257/314
• CPC Class Codes: H10B 41/30 characterised by the memory core region
• CPC Class Codes: H10B 69/00 Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices

Abstract

A semiconductor device includes a semiconductor substrate; a first insulating film formed on the top surface of the semiconductor substrate; a first gate electrode formed on the first insulating film; a second insulating film having a three-layered structure made by sequentially depositing a first kind of insulating layer, a second kind of insulating layer and a first kind of insulating layer on the first gate electrode; a second gate electrode formed on the second insulating film; a first plane including the side surface of the first gate electrode or the side surface of the second gate electrode; and a second plane including the side surface of the second kind of insulating layer, wherein distance between said first plane and said second plane does not exceed 5 nm.

Claims

1. A semiconductor device comprising:

a semiconductor substrate;

a first insulating film formed on the top surface of the semiconductor substrate;

a first gate electrode formed on the first insulating film;

a second insulating film having a three-layered structure made by sequentially depositing a first kind of insulating layer, a second kind of insulating layer and a first kind of insulating layer on the first gate electrode;

a second gate electrode formed on the second insulating film;

a first plane including the side surface of the first gate electrode or the side surface of the second gate electrode; and

a second plane including the side surface of the second kind of insulating layer,

wherein distance between said first plane and said second plane does not exceed 5 nm.

2. The semiconductor device according to claim 1, wherein a first end portion forming the boundary between the top surface of the first gate electrode and the side surface of the first gate electrode has a radius of curvature not smaller than 1 nm.

3. The semiconductor device according to claim 1, wherein a second end portion forming the boundary between the bottom surface of the second gate electrode and the side surface of the second gate electrode has a radius of curvature not smaller than 1 nm.

4. The semiconductor device according to claim 2, wherein a second end portion forming the boundary between the bottom surface of the second gate electrode and the side surface of the second gate electrode has a radius of curvature not smaller than 1 nm.

5. The semiconductor device according to claim 1, wherein distance between the first plane and the second plane is not smaller than 2 nm.

6. The semiconductor device according to claim 1, wherein said first kind of insulating layer is a silicon oxide film, said second kind of insulting film is a silicon nitride film, and said second insulating film is an ONO film made up of the silicon oxide films and the silicon nitride film.

7. The semiconductor device according to claim 2, wherein said first kind of insulating layer is a silicon oxide film, said second kind of insulting film is a silicon nitride film, and said second insulating film is an ONO film made up of the silicon oxide films and the silicon nitride film.

8. The semiconductor device according to claim 3, wherein said first kind of insulating layer is a silicon oxide film, said second kind of insulting film is a silicon nitride film, and said second insulating film is an ONO film made up of the silicon oxide films and the silicon nitride film.

9. The semiconductor device according to claim 5, wherein said first kind of insulating layer is a silicon oxide film, said second kind of insulting film is a silicon nitride film, and said second insulating film is an ONO film made up of the silicon oxide films and the silicon nitride film.

10. The semiconductor device according to claim 1, which is a nonvolatile storage device in which said first gate electrode is a floating gate electrode capable of holding an electric charge, and said second gate electrode is a control gate electrode for controlling injection and withdrawal of the electric charge into or from said floating gate.

11. The semiconductor device according to claim 6, which is a nonvolatile storage device in which said first gate electrode is a floating gate electrode capable of holding an electric charge, and said second gate electrode is a control gate electrode for controlling injection and withdrawal of the electric charge into or from said floating gate.