Semiconductor device and method for forming the same
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsShunpei YAMAZAKI, Yasuhiko TAKEMURA
Life of this patent
Estimating the term…
Abstract
An improved type thin film semiconductor device and a method for forming the same are described. That is, in a thin film semiconductor device such as TFT formed on an insulating substrate, it is possible to prevent the intrusion of a mobile ion from a substrate or other parts, by forming the first blocking film comprising a silicon nitride, an aluminum oxide, an aluminum nitride, a tantalum oxide, and the like, under the semiconductor device through an insulating film used in a buffering, and then, by forming the second blocking film on TFT, and further, by covering TFT with said first and second blocking films.
Claims20
A method for forming a semiconductor device comprising the steps of:
- forming a first blocking film comprising silicon nitride over a glass substrate;
- forming a first insulating film comprising silicon oxide over the blocking film;
- forming a semiconductor film on the first insulating film;
- forming a second insulating film on the semiconductor film;
- forming a gate electrode over the semiconductor film with the second insulating film interposed therebetween;
- and
- forming a second blocking film comprising silicon nitride over the gate electrode, the second insulating film and the semiconductor film;
- and
- subjecting the semiconductor film to annealing after forming the second blocking film.
A method for forming a semiconductor device comprising the steps of:
- forming a first blocking film comprising silicon nitride over a glass substrate;
- forming a first insulating film comprising silicon oxide over the first blocking film;
- forming a semiconductor layer comprising silicon on the first insulating film;
- etching the semiconductor layer to form a semiconductor film including a region to be a channel region;
- forming a gate insulating film over the semiconductor film;
- forming a gate electrode over the semiconductor film with the gate insulating film interposed therebetween;
- and
- forming a second blocking film comprising silicon nitride over the gate electrode wherein the second blocking film extends beyond edges of the semiconductor film to contact the first insulating film;
- and
- subjecting the semiconductor film to annealing after forming the second blocking film.
A method for forming a semiconductor device comprising the steps of:
- forming a first blocking film comprising silicon nitride over a glass substrate;
- forming a first insulating film comprising silicon oxide and fluorine over the first blocking film;
- forming a semiconductor layer comprising silicon on the first insulating film;
- etching the semiconductor layer to form a semiconductor film including a region to be a channel region;
- forming a gate insulating film over the semiconductor film;
- forming a gate electrode over the semiconductor film with the gate insulating film interposed therebetween;
- and
- forming a second blocking film comprising silicon nitride over the gate electrode wherein the second blocking film extends beyond edges of the semiconductor film to contact the first insulating film;
- and
- subjecting the semiconductor film to annealing after forming the second blocking film.
Dependencies are inferred from the claim text.