Controlled Orientation and Improved Photovoltaic Characteristics of Cu(In,Ga)Se2Solar Cells via Using In2Se3Seeding Layers

Abstract

In2Se3films were utilized as seeding layers in the synthesis of Cu(In,Ga)Se2films via the spin-coating route. Selenizing the indium-containing precursors at 400°C resulted in the formation of the hexagonalγ-In2Se3with the preferred (006) orientation. Increasing the selenization temperature to 500°C yielded the (300)-orientedγ-In2Se3. Using the preferred (006)-oriented In2Se3as seeding layers produced the preferred (112)-oriented Cu(In,Ga)Se2film because of the crystalline symmetry. In contrast, the use of the (300)-oriented In2Se3as seeding layers yielded the (220/204)-oriented Cu(In,Ga)Se2films. According to results obtained using SEM and the Hall effect, (112)-oriented Cu(In,Ga)Se2films had a denser morphology and more favorable electrical properties. Using the (112)-oriented Cu(In,Ga)Se2films as the absorber layer in the solar devices resulted in a significant increase in the conversion efficiency.