Semiconductor device and method for fabricating the same

A method for fabricating a semiconductor device, comprising steps of:

• selectively introducing a metal or a metal compound which promotes crystallization of silicon to a semiconductor film comprising silicon;
• growing crystal by a first heat treatment in a direction parallel to the film from the region to which said metal or said metal compound has been selectively introduced;
• forming a thermal oxide film on the surface of the region where said crystal has been grown by implementing a second heat treatment within an oxidizing atmosphere at a temperature of 700.degree. C. or higher;
• eliminating said thermal oxide film;
• annealing the semiconductor film in a plasma atmosphere containing oxygen and hydrogen after the eliminating step;
• and
• forming a semiconductor island of said semiconductor device by using the region from which said thermal oxide film has been eliminated.

A method for fabricating a semiconductor device, comprising steps of:

• intentionally introducing a metal or a metal compound which promotes crystallization of silicon to a semiconductor film comprising silicon and crystallizing said semiconductor film by a first heat treatment to obtain a crystal semiconductor film;
• eliminating or reducing said metal or said metal compound existing within said crystal semiconductor film by implementing a second heat treatment within an oxidizing atmosphere containing a halogen element at a temperature of 700.degree. C. or higher;
• eliminating a thermal oxide film formed in the previous eliminating or reducing step;
• forming a semiconductor island of a thin film transistor by implementing patterning of said crystal semiconductor film;
• and
• forming another thermal oxide film which composes at least a part of a gate insulating film on the surface of said semiconductor island by means of thermal oxidation.

A method for fabricating a semiconductor device, comprising steps of:

• forming a semiconductor film comprising silicon on a substrate having an insulating surface;
• intentionally introducing a metal or a metal compound which promotes crystallization of silicon into said semiconductor film;
• obtaining a crystal semiconductor film by crystallizing said semiconductor film by a first heat treatment in the temperature range of 750.degree. C. to 1100.degree. C.;
• forming a semiconductor island of said semiconductor device by patterning said crystal semiconductor film;
• eliminating or reducing said metal or said metal compound existing within said crystal semiconductor film by implementing a second heat treatment within an oxidizing atmosphere containing a halogen element;
• eliminating a thermal oxide film formed in the previous eliminating or reducing step;
• and
• forming another thermal oxide film after eliminating said thermal oxide film by implementing another thermal oxidation;
• wherein a temperature of said second heat treatment is higher than that of said first heat treatment.

A method for fabricating a semiconductor device, comprising steps of:

• forming a semiconductor film comprising silicon on a substrate having an insulating surface;
• intentionally introducing a metal or a metal compound which promotes crystallization of silicon into said semiconductor film;
• obtaining a crystal semiconductor film by crystallizing said semiconductor film by a first heat treatment in the temperature range of 750.degree. C. to 1100.degree. C.;
• forming a semiconductor island of said semiconductor device by patterning said crystal semiconductor film;
• implementing a second heat treatment within an oxidizing atmosphere containing a halogen element to cause said metal or said metal compound existing within said crystal semiconductor film to be gettered within a thermal oxide film to be formed;
• eliminating said thermal oxide film formed in the previous second heat treatment step;
• and
• forming another thermal oxide film after eliminating said thermal oxide film by implementing another thermal oxidation,
• wherein a temperature of said second heat treatment is higher than that of said first heat treatment.

A method for fabricating a semiconductor device, comprising steps of:

• forming a semiconductor film comprising silicon on a substrate having an insulating surface;
• intentionally and selectively introducing a metal or a metal compound which promotes crystallization of silicon into said semiconductor film;
• growing crystal in a direction parallel to the film from a region of said semiconductor film into which said metal or said metal compound has been intentionally and selectively introduced by a first heat treatment in the temperature range of 750.degree. C. to 1100.degree. C.;
• forming a semiconductor island of said semiconductor device by using said region in which the crystal has been grown in the direction parallel to said film by patterning;
• implementing a second heat treatment within an oxidizing atmosphere containing a halogen element to cause said metal or said metal compound existing within said semiconductor island to be gettered within a thermal oxide film to be formed;
• eliminating said thermal oxide film formed in the previous second heat treatment step;
• and
• forming another thermal oxide film after eliminating said thermal oxide film formed in said second heat treatment step by implementing another thermal oxidation,
• wherein a temperature of said second heat treatment is higher than that of said first heat treatment.

A method for fabricating a semiconductor device comprising steps of:

• intentionally introducing a metal or a metal compound which promotes crystallization of silicon to a semiconductor film comprising silicon and crystallizing said semiconductor film by a first heat treatment using said metal or said metal compound to obtain a crystal semiconductor film;
• implementing a second heat treatment within an oxidizing atmosphere containing a halogen element at a temperature of 700.degree. C. or higher to cause said metal or said metal compound to be gettered from said semiconductor film;
• eliminating a thermal oxide film formed in the previous second heat treatment step;
• and
• forming another thermal oxide film after eliminating said thermal oxide film formed in said second heat treatment step by implementing another thermal oxidation.

A method for fabricating a semiconductor device comprising steps of:

• intentionally introducing a metal or a metal compound which promotes crystallization of silicon to a semiconductor film comprising silicon and crystallizing said semiconductor film by a first heat treatment to obtain a crystal semiconductor film;
• eliminating or reducing said metal or said metal compound existing within said crystal semiconductor film by implementing a second heat treatment within an oxidizing atmosphere at a temperature of 700.degree. C. or higher;
• eliminating a thermal oxide film formed in the previous eliminating or reducing step;
• annealing the semiconductor film in a plasma atmosphere containing oxygen and hydrogen after the eliminating step of said thermal oxide film;
• forming a semiconductor island of a thin film transistor by implementing patterning of said crystal semiconductor film;
• and
• forming another thermal oxide film which composes at least a part of a gate insulating film on the surface of said semiconductor island by means of thermal oxidation.