Method of manufacturing semiconductor device
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsShunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Akiharu Miyanaga
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Abstract
In a method of manufacturing a semiconductor device, a first heat treatment for crystallization is conducted after nickel elements are introduced in an amorphous silicon film. Then, after the crystalline silicon film is obtained, a heat treatment is again conducted through the heating method which is identical with the first heat treatment. In this state, HCl or the like is added to the atmosphere to conduct gettering of the nickel elements remaining in the crystalline silicon film. With this process, there can be obtained a crystalline silicon film low in the concentration of the metal elements and high in crystallinity.
Claims31
A method of forming a semiconductor device comprising the steps of:
- preparing an amorphous semiconductor film on an insulating surface;
- performing a first heat treatment to crystallize said amorphous semiconductor film;
- performing a second heat treatment at a higher temperature than said first heat treatment, and in an atmosphere comprising at least a material selected from the group consisting of Ar, N2, He, and Ne,
- wherein said second heat treatment is performed at a temperature of 450-1050° C., and
- wherein said crystallized semiconductor film after said second heat treatment has a spin density in the range of 3×1017 cm−3 or less.
A method of forming a semiconductor device comprising the steps of:
- preparing an amorphous semiconductor film on an insulating surface;
- crystallizing said amorphous semiconductor film;
- heating said crystallized semiconductor film at a higher temperature than said crystallizing step, and in an atmosphere comprising at least a material selected from the group consisting of Ar, N2, He, and Ne;
- and
- irradiating said crystallized semiconductor film with a laser light after said heating step,
- wherein said heating step is carried out at a temperature of 450-1050° C.,
- wherein said crystallized semiconductor film after said heat step has a spin density in the range of 3×1017 cm−3 or less,
- wherein said crystallized semiconductor film comprises hydrogen at 5 atoms % or less to 1×1015 cm−3.
A method of forming a semiconductor device comprising the steps of:
- preparing an amorphous semiconductor film on an insulating surface;
- performing a first heat treatment to crystallize said amorphous semiconductor film;
- performing a second heat treatment at a higher temperature than said first heat treatment, and in an atmosphere comprising at least a material selected from the group consisting of Ar, N2, He, and Ne, so that a substantially single crystal semiconductor region having no grain boundary is obtained,
- wherein said second heat treatment is performed at a temperature of 450-1050° C., and
- wherein said crystallized semiconductor film after said second heat treatment has a spin density in the range of 3×1017 cm−3 or less.
Dependencies are inferred from the claim text.