Method for producing a thin film transistor and method for forming an electrode

A thin film transistor producing method for producing a thin film transistor which includes a gate electrode, a gate insulating film arranged on a surface of the gate electrode, a semiconductor layer arranged on the gate insulating film, a source electrode in contact with the semiconductor layer, a drain electrode in contact with the semiconductor layer, and an insulating film in contact with the drain electrode and the source electrode and composed of a film of silicon nitride,

• the thin film transistor producing method comprising the steps of:
• forming a second copper thin film constituting the source electrode and the drain electrode on a surface of the semiconductor layer by incorporating oxygen into at least a portion in close contact with the semiconductor layer;
• introducing a treatment gas containing an ammonia gas into a vacuum chamber in which an object to be processed is placed, the object to be processed having a surface of the second copper thin film exposed;
• exposing the surface of the second copper thin film to the ammonia gas without generating a plasma inside the vacuum chamber for a surface treatment;
• introducing a raw material gas including a gas of a silicon compound containing Si and H in a chemical structure and a nitrogen containing gas including nitrogen in a chemical structure into the vacuum chamber;
• and
• forming a plasma of the raw material gas, thereby growing the thin film of silicon nitride on the surface of the second copper thin film.

An electrode forming method for forming a copper electrode of copper or a copper alloy on a surface of glass, a surface of silicon or surface of a silicon compound exposed on an object to be processed, the method comprising the steps of:

• forming a copper electrode on a substrate by incorporating oxygen into at least a layer in contact with the substrate;
• performing a surface treatment by exposing a surface of the copper electrode to a treatment gas containing an ammonia gas;
• and
• forming a thin film of silicon nitride on the copper electrode by introducing a raw material gas including a gas of a silicon compound containing Si and H in a chemical structure and a nitrogen containing gas including nitrogen in a chemical structure into a film forming atmosphere in which the surface-treated substrate is placed to generate a plasma, and forming a thin film of silicon nitride on the copper electrode.