Semiconductor device
AssigneesSemiconductor Energy Laboratory Co., Ltd., Sharp Kabushiki Kaisha
InventorsJun Koyama, Hidehito Kitakado, Masataka Itoh, Hiroyuki Ogawa
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Abstract
The present invention has provided on a back channel side of the TFT a blocking layer that is formed by laminating a 50 nm to 100 nm thick silicon oxynitride film (A) and a 30 nm to 70 nm thick silicon oxynitride film (B). By forming a lamination structure of such silicon oxynitride films, not only can be the contaminations caused by impurities such as alkali metallic elements from the substrate prevented, but the fluctuations in the electrical characteristics of the TFT can be reduced.
Claims40
A semiconductor device having at least one thin film transistor over a substrate, comprising:
- a first silicon oxynitride film formed in contact with the substrate, a second silicon oxynitride film formed in contact with the first silicon oxynitride film, and a semiconductor layer on the second silicon oxynitride film,
- wherein a composition ratio of nitrogen to oxygen of the first silicon oxynitride film is larger than that of the second silicon oxynitride film, and
- wherein a film thickness of the first silicon oxynitride film is between 50 nm and 100 nm, and a film thickness of the second silicon oxynitride film is between 30 nm and 70 nm.
A semiconductor device having at least one thin film transistor over a substrate, comprising:
- a first silicon oxynitride film formed in contact with the substrate, a second silicon oxynitride film formed in contact with the first silicon oxynitride film, and a semiconductor layer on the second silicon oxynitride film,
- wherein a composition ratio of hydrogen to oxygen of the first silicon oxynitride film is larger than that of the second silicon oxynitride film, and
- wherein a film thickness of the first silicon oxynitride film is between 50 nm and 100 nm. and a film thickness of the second silicon oxynitride film is between 30 nm and 70 nm.
A semiconductor device having at least one thin film transistor over a substrate, comprising:
- a first silicon oxynitride film formed in contact with the substrate, a second silicon oxynitride film formed in contact with the first silicon oxynitride film, and a semiconductor layer on the second silicon oxynitride film,
- wherein an oxygen concentration of the second silicon oxynitride film is larger than that of the first silicon oxynitride film, and
- wherein a film thickness of the first silicon oxynitride film is between 50 nm and 100 nm, and a film thickness of the second silicon oxynitride film is between 30 nm and 70 nm.
A semiconductor device having at least one thin film transistor over a substrate, comprising:
- a first silicon oxynitride film formed in contact with the substrate, a second silicon oxynitride film formed in contact with the first silicon oxynitride film, and a semiconductor layer on the second silicon oxynitride film,
- wherein a nitrogen concentration of the first silicon oxynitride film is larger than or equal to that of the second silicon oxynitride film, and
- wherein a film thickness of the first silicon oxynitride film is between 50 nm and 100 nm, and
- a film thickness of the second silicon oxynitride film is between 30 nm and 70 nm.
A semiconductor device having at least one thin film transistor over a substrate, comprising:
- a first silicon oxynitride film formed in contact with the substrate, a second silicon oxynitride film formed in contact with the first silicon oxynitride film, and a semiconductor layer on the second silicon oxynitride film,
- wherein a hydrogen concentration of the first silicon oxynitride film is larger than or equal to that of the second silicon oxynitride film, and
- wherein a film thickness of the first silicon oxynitride film is between 50 nm and 100 nm, and a film thickness of the second silicon oxynitride film is between 30 nm and 70 nm.
Dependencies are inferred from the claim text.