Alkali metal-incorporated chalcopyrite compound-based thin film and method of fabricating the same

A method of fabricating a chalcopyrite compound-based thin film, the method comprising:

• applying a first metal precursor paste onto a substrate and thermally treating the applied first metal precursor paste to form a first metal oxide thin film;
• applying an alkali precursor solution onto the first metal oxide thin film and thermally treating the applied precursor solution to form an alkali metal layer;
• applying a second metal precursor paste onto the alkali metal layer and thermally treating the applied second metal precursor paste to form a second metal oxide thin film;
• and
• thermally treating a stack of the first metal oxide thin film, the alkali metal layer, and the second metal oxide thin film under an atmosphere of a sulfur precursor in a gas state, a selenium precursor in a gas state, or a mixture thereof.

A method of fabricating a chalcopyrite compound-based thin film, the method comprising:

• applying a metal precursor paste onto a substrate and thermally treating the applied metal precursor paste to form a metal oxide thin film;
• and
• thermally treating the metal oxide thin film under an atmosphere of a sulfur precursor in a gas state, a selenium precursor in a gas state, or a mixture thereof,
• wherein the metal precursor paste comprises at least one Group IB metal precursor, at least one Group IIIA metal precursor, or a mixture thereof;
• and an alkali metal or an alkali metal precursor.

A method of fabricating a chalcopyrite compound-based thin film, the method comprising:

• applying a first metal precursor paste onto a substrate and thermally treating the applied first metal precursor paste to form a first metal oxide thin film;
• applying a second metal precursor paste onto the first metal oxide thin film and thermally treating the applied second metal precursor paste to form a second metal oxide thin film;
• and
• thermally treating a stack of the first metal oxide thin film and the second metal oxide thin film under an atmosphere of a sulfur precursor in a gas state, a selenium precursor in a gas state, or a mixture thereof,
• wherein the first metal precursor paste and the second metal precursor paste each independently comprise at least one Group IB metal precursor, at least one Group IIIA metal precursor, or a mixture thereof, and
• the second metal precursor paste further comprises an alkali metal precursor.