Method of manufacturing a semiconductor device having a capacitor
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsMakoto Ohi, Hideaki Arima, Natsuo Ajika
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Abstract
A capacitor includes a polycrystalline silicon layer 1 as a lower electrode layer, a dielectric layer 112, and a polycrystalline silicon layer 113 as an upper electrode layer. The dielectric layer 112 is formed by an oxynitride film 2, a silicon nitride film 3 and a top oxide film 4. A film thickness t.sub.3 of the top oxide film 4 is controlled to be less than 20 .ANG.. Capacitance of the capacitor can be increased while improving the duration of life of the dielectric layer, resulting in a highly reliable capacitor.
Claims3
A method of manufacturing a semiconductor device having a capacitor, comprising the steps of:
- forming a first electrode layer on a semiconductor substrate,
- forming an oxynitride film on said first electrode layer,
- forming a nitride film on said oxynitride film,
- forming an oxide film on said nitride film by thermal oxidation,
- placing said semiconductor substrate under an inert gas atmosphere after the formation of said oxide film, and
- forming a second electrode layer on said oxide film after placing said semiconductor substrate under an inert gas atmosphere, wherein said oxide film has a thickness of less than 20 .ANG., further comprising lowering the temperature of said inert gas atmosphere, after placing the semiconductor substrate under an inert gas atmosphere, to a temperature sufficient to suppress growth of said oxide film.
A method of manufacturing a semiconductor device having a capacitor, which method comprises:
- forming a first electrode layer on a semiconductor substrate;
- forming a silicon oxynitride film having a thickness in the range of 17 .ANG. to 25 .ANG. on said first electrode layer;
- forming a silicon nitride film having a thickness in the range of 20 .ANG. to 50 .ANG. on said oxynitride film;
- forming a silicon oxide film having a thickness in the range of 5 .ANG. to less than 20 .ANG. on said nitride film;
- and
- forming a second electrode layer on said oxide film.
A method of manufacturing a semiconductor device having a capacitor, which method comprises:
- forming a first electrode layer on a semiconductor substrate;
- forming a dielectric layer having an overall thickness in the range of 42 .ANG. to less than 95 .ANG. on said first electrode layer by:
- forming a silicon oxynitride film on said first electrode layer;
- forming a silicon nitride film having a thickness in the range of 20 .ANG. to 50 .ANG. on said oxynitride film;
- and
- forming a silicon oxide film having a thickness less than 20 .ANG. on said nitride film;
- and
- forming a second electrode layer formed on said dielectric layer.
Dependencies are inferred from the claim text.