Semiconductor device with field shield electrode
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsShigenobu Maeda, Toshiaki Iwamatsu, Shigeto Maegawa, Takashi Ipposhi, Yasuo Yamaguchi, Yuichi Hirano
Life of this patent
Estimating the term…
Abstract
An FS upper nitride film (15) is formed on the upper surface of an FS electrode (5). Therefore, the upper surface of the FS electrode (5) is not exposed even when an FS upper oxide film (41) is partially almost removed in the manufacturing process. Thus, a semiconductor device which prevents degradation in operation characteristics and reliability due to existence of an FS insulating layer can be provided.
Claims16
A semiconductor device having a field-shield isolation structure selectively formed on an upper surface of a semiconductor substrate, said field-shield isolation structure comprising:
- an insulating film formed on the upper surface of said semiconductor substrate;
- a field-shield electrode formed on an upper surface of said insulating film over a boundary region that separates element regions of the semiconductor device, said boundary region including a region formed on opposite sides of a channel covered by a conduction controlling gate electrode, with no channel being formed on said region;
- an oxidation-resistant film formed so as to cover an upper surface of said field-shield electrode;
- a first oxide film covering an upper surface of said oxidation-resistant film;
- and
- a second oxide film directly contacting side surfaces of said first oxide film, said oxidation-resistant film, and said field-shield electrode,
- wherein said field-shield isolation structure is configured to electrically isolate the element regions from each other.
A semiconductor device having a field-shield isolation structure selectively formed on a semiconductor substrate, said field-shield isolating structure comprising:
- an insulating film having resistance to oxidation formed on an upper surface of said semiconductor substrate;
- a field-shield electrode formed on an upper surface of said insulating film over a boundary region that separates element regions of the semiconductor device, said boundary region including a region formed on opposite sides of a channel covered by a conduction controlling gate electrode;
- a first oxidation-resistant film formed so as to cover an upper surface of said field-shield electrode;
- and
- a second oxidation-resistant film formed so as to be in direct contact with side surfaces of said first oxidation-resistant film and said field-shield electrode,
- wherein said field-shield isolation structure is configured to electrically isolate the element regions from each other.
A semiconductor device having a field-shield isolation structure selectively formed on a semiconductor substrate so as to isolate separate element regions making up the semiconductor device,
- said field-shield isolation structure comprising:
- an insulating film fonned on an upper surface of said semiconductor substrate;
- a field-shield electrode formed on an upper surface of said insulating film;
- a first oxide film covering an upper surface of said field-shield electrode;
- a second oxide film covering side surfaces of said first oxide film and said field-shield electrode,
- and wherein at least one of the element regions isolated by said field-shield isolation structure includes an MOS transistor, and
- a thickness of said first oxide film is larger than the total of those of a side wall oxide film formed in an end surface of a gate electrode of said MOS transistor for formation of a lightly doped drain layer of said MOS transistor and a silicide protection film formed on a portion of said MOS transistor.
Dependencies are inferred from the claim text.