Copper indium gallium selenide absorption layer and preparation method thereof, solar cell and preparation method thereof

A preparation method of a solar cell, wherein comprises the preparation method of a copper indium gallium selenide absorption layer as follows:

• step 100:
• forming a copper gallium alloy layer and an indium layer sequentially on a substrate to obtain a prefabricated copper indium gallium film;
• step 200:
• placing the prefabricated copper indium gallium film into a reaction chamber having a first preset temperature threshold;
• introducing a selenium atmosphere having a first preset carrier gas flow value into the reaction chamber;
• the prefabricated copper indium gallium film reacting in the selenium atmosphere having the first carrier gas flow value for a first preset duration, such that an unsaturated In—Se binary phase and an unsaturated Cu—Se binary phase are formed on a surface of the prefabricated copper indium gallium film;
• step 300:
• introducing a selenium atmosphere having a second preset carrier gas flow value into the reaction chamber;
• the prefabricated copper indium gallium film having an unsaturated In—Se binary phase and an unsaturated Cu—Se binary phase formed on a surface thereof reacting in a selenium atmosphere having the second carrier gas flow value for a second preset duration, such that a selenium source contained in the selenium atmosphere diffuses toward a bottom of the prefabricated copper indium gallium film, and reacts with the copper indium gallium contained in the prefabricated copper indium gallium film to obtain a copper indium gallium selenide prefabricated film formed on a surface of the substrate;
• step 400:
• annealing the copper indium gallium selenide prefabricated film formed on the surface of the substrate within a second preset temperature threshold and a third preset duration to obtain a copper indium gallium selenide absorption layer.

A copper indium gallium selenide absorption layer prepared by the preparation method of the copper indium gallium selenide absorption layer, wherein the method comprises:

• step 100:
• forming a copper gallium alloy layer and an indium layer sequentially on a substrate to obtain a prefabricated copper indium gallium film;
• step 200:
• placing the prefabricated copper indium gallium film into a reaction chamber having a first preset temperature threshold;
• introducing a selenium atmosphere having a first preset carrier gas flow value into the reaction chamber;
• the prefabricated copper indium gallium film reacting in the selenium atmosphere having the first carrier gas flow value for a first preset duration, such that an unsaturated In—Se binary phase and an unsaturated Cu—Se binary phase are formed on a surface of the prefabricated copper indium gallium film;
• step 300:
• introducing a selenium atmosphere having a second preset carrier gas flow value into the reaction chamber;
• the prefabricated copper indium gallium film having an unsaturated In—Se binary phase and an unsaturated Cu—Se binary phase formed on a surface thereof reacting in a selenium atmosphere having the second carrier gas flow value for a second preset duration, such that a selenium source contained in the selenium atmosphere diffuses toward a bottom of the prefabricated copper indium gallium film, and reacts with the copper indium gallium contained in the prefabricated copper indium gallium film to obtain a copper indium gallium selenide prefabricated film formed on a surface of the substrate;
• step 400:
• annealing the copper indium gallium selenide prefabricated film formed on the surface of the substrate within a second preset temperature threshold and a third preset duration to obtain a copper indium gallium selenide absorption layer.

A solar cell comprising the copper indium gallium selenide absorption layer, wherein the copper indium gallium selenide absorption layer is prepared as following steps:

• step 100:
• forming a copper gallium alloy layer and an indium layer sequentially on a substrate to obtain a prefabricated copper indium gallium film;
• step 200:
• placing the prefabricated copper indium gallium film into a reaction chamber having a first preset temperature threshold;
• introducing a selenium atmosphere having a first preset carrier gas flow value into the reaction chamber;
• the prefabricated copper indium gallium film reacting in the selenium atmosphere having the first carrier gas flow value for a first preset duration, such that an unsaturated In—Se binary phase and an unsaturated Cu—Se binary phase are formed on a surface of the prefabricated copper indium gallium film;
• step 300:
• introducing a selenium atmosphere having a second preset carrier gas flow value into the reaction chamber;
• the prefabricated copper indium gallium film having an unsaturated In—Se binary phase and an unsaturated Cu—Se binary phase formed on a surface thereof reacting in a selenium atmosphere having the second carrier gas flow value for a second preset duration, such that a selenium source contained in the selenium atmosphere diffuses toward a bottom of the prefabricated copper indium gallium film, and reacts with the copper indium gallium contained in the prefabricated copper indium gallium film to obtain a copper indium gallium selenide prefabricated film formed on a surface of the substrate;
• step 400:
• annealing the copper indium gallium selenide prefabricated film formed on the surface of the substrate within a second preset temperature threshold and a third preset duration to obtain a copper indium gallium selenide absorption layer.