Semiconductor device and a method of manufacturing the same

Claim 1

A method of manufacturing a semiconductor device comprising the steps of: forming a semiconductor layer over a substrate; forming a convex region comprising polysilicon or a silicide over said semiconductor layer; implanting an impurity of a first concentration in said semiconductor layer by using said convex region as a mask; forming spacers comprising an insulator on side surfaces of said convex region; implanting an impurity of a second concentration in said semiconductor layer by using said convex region and said spacers as a mask; annealing said semiconductor layer thereby activating said impurities of said first and second concentrations, after completion of said implanting of said impurities of first and second concentrations; removing said convex region; and forming a gate electrode comprising a metal after said annealing in a region defined by said spacers.

Claim 2

A method of manufacturing a semiconductor device comprising the steps of: forming a semiconductor layer over a substrate; forming a convex region comprising polysilicon or a silicide over said semiconductor layer; implanting an impurity of a first concentration in said semiconductor layer by using said convex region as a mask; forming spacers comprising an insulator on side surfaces of said convex region; implanting an impurity of a second concentration in said semiconductor layer by using said convex region and said spacers as a mask; annealing said semiconductor layer thereby activating said impurities of said first and second concentrations, after completion of said implanting of said impurities of first and second concentrations; removing said convex region; and forming a gate electrode comprising a metal after said annealing in a region defined by said spacers.

Claim 3

A method of manufacturing a semiconductor device comprising the steps of: forming an active layer or active region having a gate-insulating film thereon; forming a convex region comprising polysilicon or a silicide over said gate-insulating film; forming spacers comprising an insulator on side surfaces of said convex region; implanting impurity ions into said active layer or active region, using said convex region and said spacers as a mask; performing a heat treatment after completion of said implanting of impurity ions; removing said convex region; and forming a gate electrode comprising aluminum in a region defined by said spacers after said heat treatment.

Claim 4

A method of manufacturing a semiconductor device comprising the steps of: forming an active layer or active region having a gate-insulating film thereon; forming a convex region comprising polysilicon or a silicide over said gate-insulating film; forming spacers comprising an insulator on side surfaces of said convex region; implanting impurity ions into said active layer or active region, using said convex region and said spacers as a mask; performing a heat treatment after completion of said implanting of impurity ions; removing said convex region; and forming a gate electrode comprising aluminum in a region defined by said spacers after said heat treatment.

Claim 5

A method of manufacturing a semiconductor device comprising the steps of: forming an active layer or active regions having a gate-insulating film thereon; forming a convex region comprising polysilicon or a silicide over said gate-insulating film; forming spacers comprising an insulator on side surfaces of said convex region; implanting impurity ions into said active layer or active region, using said convex region and said spacers as a mask; performing a heat treatment to anneal said active layer or active regions after completion of implanting said impurity ions; removing said convex region; and forming a gate electrode comprising aluminum in a region defined by said spacers after said heat treatment, wherein said heat treatment prior to formation of said gate electrode is conducted at such a high temperature that said gate electrode would be damaged if said gate electrode was exposed to said high temperature.

Claim 6

A method of manufacturing a semiconductor device comprising the steps of: forming an active layer or active regions having a gate-insulating film thereon; forming a convex region comprising polysilicon or a silicide over said gate-insulating film; forming spacers comprising an insulator on side surfaces of said convex region; implanting impurity ions into said active layer or active region, using said convex region and said spacers as a mask; performing a heat treatment to anneal said active layer or active regions after completion of implanting said impurity ions; removing said convex region; and forming a gate electrode comprising aluminum in a region defined by said spacers after said heat treatment, wherein said heat treatment prior to formation of said gate electrode is conducted at such a high temperature that said gate electrode would be damaged if said gate electrode was exposed to said high temperature.

Claim 10

A method of manufacturing a semiconductor device comprising the steps of: forming a non-single crystalline semiconductor film over a substrate; forming a gate insulating film over said semiconductor film; forming a dummy electrode comprising polysilicon or a silicide over said gate insulating film; forming side wall spacers comprising an insulating material on side surfaces of said dummy gate electrode; introducing ions of an impurity into portions of said semiconductor film with said dummy gate electrode and said side wall spacers used as a mask; annealing said semiconductor film after completion of said introduction of said impurity thereby activating said impurity; etching said dummy electrode after said annealing whereby a groove is formed between said side wall spacers over said gate insulating film; forming a conductive film comprising aluminum; etching said conductive film comprising aluminum thereby forming a gate electrode within said groove; wherein said heat treatment prior to formation of said gate electrode comprising aluminum is conducted at such a high temperature that said gate electrode would be damaged if said gate electrode was exposed to said high temperature.

Claim 11

A method of manufacturing a semiconductor device comprising the steps of: forming a non-single crystalline semiconductor film over a substrate; forming a gate insulating film over said semiconductor film; forming a dummy electrode comprising polysilicon or a silicide over said gate insulating film; forming side wall spacers comprising an insulating material on side surfaces of said dummy gate electrode; introducing ions of an impurity into portions of said semiconductor film with said dummy gate electrode and said side wall spacers used as a mask; annealing said semiconductor film after completion of said introduction of said impurity thereby activating said impurity; etching said dummy electrode after said annealing whereby a groove is formed between said side wall spacers over said gate insulating film; forming a conductive film comprising aluminum; etching said conductive film comprising aluminum thereby forming a gate electrode within said groove; wherein said heat treatment prior to formation of said gate electrode comprising aluminum is conducted at such a high temperature that said gate electrode would be damaged if said gate electrode was exposed to said high temperature.

Claim 12

A method of manufacturing a semiconductor device comprising the following sequential steps of: forming a non-single crystalline semiconductor film over a substrate; forming a gate insulating film over said semiconductor film; forming a dummy electron over said gate insulating film; introducing ions of a first impurity into said semiconductor film with said dummy electrode used as a first mask at a first concentration; forming side wall spacers comprising an insulating material on side surfaces of said dummy electrode; introducing ions of a second impurity into portions of said semiconductor film with said dummy electrode and said side wall spacers used as a second mask at a second concentration larger than said first concentration, thereby, forming lightly doped regions below said side wall spacers; annealing said semiconductor film after completion of said introduction of said first and second impurities thereby activating said impurities; and then replacing said dummy electrode with a gate electrode comprising aluminum, wherein said annealing step prior to formation of said gate electrode comprising aluminum is carried out at such a condition that said gate electrode would be damaged if said gate electrode was exposed to said high temperature.

Claim 13

A method of manufacturing a semiconductor device comprising the following sequential steps of: forming a non-single crystalline semiconductor film over a substrate; forming a gate insulating film over said semiconductor film; forming a dummy electron over said gate insulating film; introducing ions of a first impurity into said semiconductor film with said dummy electrode used as a first mask at a first concentration; forming side wall spacers comprising an insulating material on side surfaces of said dummy electrode; introducing ions of a second impurity into portions of said semiconductor film with said dummy electrode and said side wall spacers used as a second mask at a second concentration larger than said first concentration, thereby, forming lightly doped regions below said side wall spacers; annealing said semiconductor film after completion of said introduction of said first and second impurities thereby activating said impurities; and then replacing said dummy electrode with a gate electrode comprising aluminum, wherein said annealing step prior to formation of said gate electrode comprising aluminum is carried out at such a condition that said gate electrode would be damaged if said gate electrode was exposed to said high temperature.