Method of forming channel in thin film transistor using non-ionic excited species

A method of producing a bottom gate thin film transistor, comprising the steps of:

• forming a gate electrode on an insulating substrate;
• forming a gate insulating film over the gate electrode;
• forming a first semiconductor thin film for a channel over the gate insulating film;
• forming a second semiconductor thin film for a source and a drain over the first semiconductor thin film;
• processing stacked layers of the first semiconductor thin film and the second semiconductor thin film into an island;
• subsequent to the step of processing stacked layers, depositing a source/drain electrode metal over the stacked layers;
• etching a region of the deposited source/drain electrode metal, the region being located above the channel, in the depth direction to expose the second semiconductor thin film, whereby a source electrode and a drain electrode are formed;
• and
• nitriding the exposed portion of the second semiconductor thin film using a non-ionic nitrogen-containing decomposition product that is produced by decomposing molecules of a chemical substance containing nitrogen atoms.

A bottom gate thin film transistor comprising:

• a gate electrode formed on an insulating substrate;
• a gate insulating film formed over the gate electrode;
• a channel comprising a first semiconductor thin film stacked over the gate insulating film;
• a source region and a drain region each comprising a second semiconductor thin film that is stacked over a region of the first semiconductor thin film exclusive of the channel;
• a source electrode and a drain electrode formed on the second semiconductor thin film;
• and
• a passivation film composed of a silicon nitride film formed on the channel;
• wherein a portion of the channel contains at least one element selected from the group consisting of tungsten, tantalum, molybdenum, vanadium, platinum, and thorium, the portion of the channel being adjacent to a surface thereof which is in contact with the silicon nitride film;
• and the total atomic density of the at least one element is in the range of from 1×1016·cm−3 to 1×1019·cm−3.

A bottom gate thin film transistor comprising:

• a gate electrode formed on an insulating substrate;
• a gate insulating film formed over the gate electrode;
• a channel formed of a first semiconductor thin film stacked over the gate insulating film;
• a source and a drain each formed of a second semiconductor thin film stacked over the first semiconductor thin film;
• a nitrided region in which a portion of the second semiconductor thin film disposed immediately above the channel is nitrided;
• and
• a source electrode and a drain electrode, each formed on a portion of the second semiconductor thin film exclusive of the nitrided region;
• wherein a portion of the channel contains at least one element selected from the group consisting of tungsten, tantalum, molybdenum, vanadium, platinum, and thorium, the portion of the channel being adjacent to a surface thereof which faces the nitrided region;
• and the total atomic density of the at least one element is in the range of from 1×1016·cm−3 to 1×1019·cm−3.