Disclosed are a precursor solution for a copper-zinc-tin-sulfur (CZTS) thin film solar cell, a preparation method therefor, and the use thereof. The present invention discloses two types of simple metal complexes which are capable of formulating a high-quality precursor solution.

A method of forming a coating layer on a glass substrate in a glass manufacturing process includes: providing a first coating precursor material for a selected coating layer composition to at least one multislot coater to form a first coating region of the selected coating layer; and providing a second coating precursor material for the selected coating layer composition to the multislot coater to form a second coating region of the selected coating layer over the first region. The first coating precursor material is different than the second precursor coating material.

A method of making a coated article includes forming a first coating over a first surface of a substrate; and forming a second coating over a second surface of the substrate. The second coating includes a first conductive layer including tin oxide and at least one material selected from the group consisting of tungsten, molybdenum, and niobium.

A solar cell includes a first substrate having a first surface and a second surface. An underlayer is located over the second surface. A first conductive layer is located over the underlayer. An overlayer is located over the first conductive layer. A semiconductor layer is located over the conductive oxide layer. A second conductive layer is located over the semiconductor layer. The first conductive layer includes a conductive oxide and at least one dopant selected from the group consisting of tungsten, molybdenum, niobium, and/or fluorine.

A solar cell includes a first substrate having a first surface and a second surface. An underlayer is located over the second surface. A first conductive layer is located over the underlayer. An overlayer is located over the first conductive layer. A semiconductor layer is located over the conductive oxide layer. A second conductive layer is located over the semiconductor layer. The first conductive layer includes a conductive oxide and at least one dopant selected from the group consisting of tungsten, molybdenum, niobium, and/or fluorine.

An article, for example a solar cell, includes a first substrate having a first surface and a second surface. An underlayer is located over the second surface. A first conductive layer is located over the underlayer. An overlayer is located over the first conductive layer. A semiconductor layer is located over the conductive oxide layer. A second conductive layer is located over the semiconductor layer. The first conductive layer can include a conductive oxide and at least one dopant selected from the group consisting of tungsten, molybdenum, niobium, and/or fluorine. The overlayer can include a buffer layer having tin oxide and at least one of zinc, indium, gallium, and magnesium.

A method of making a coated article includes forming a first coating over a first surface of a substrate; and forming a second coating over a second surface of the substrate. The second coating includes a first conductive layer including tin oxide and at least one material selected from the group consisting of tungsten, molybdenum, and niobium.

An optical element that features high transmission and low reflectivity at infrared wavelengths is described. The optical element includes a substrate, an adhesion layer on the substrate, and an anti-reflection coating. Substrates include chalcogenide glasses, InAs, and GaAs. Adhesion layers include Se, ZnSe, Ga.sub.2Se.sub.3, Bi.sub.2Se.sub.3, In.sub.2Se.sub.3, ZnS, Ga.sub.2S.sub.3 and In.sub.2S.sub.3. Anti-reflection coatings include one or more layers of DLC (diamond-like carbon), ZnS, ZnSe, Ge, Si, HfO.sub.2, Bi.sub.2O.sub.3, GdF.sub.3, YbF.sub.3, In.sub.2Se.sub.3, and YF.sub.3. The optical elements show high durability and good adhesion when subjected to thermal shocks, temperature cycling, abrasion, and humidity.

A photovoltaic device (e.g., solar cell) includes: a front substrate (e.g., glass substrate); a semiconductor absorber film; a back contact including a first conductive layer of or including copper (Cu) and a second conductive layer of or including molybdenum (Mo); and a rear substrate (e.g., glass substrate). A selenium blocking layer is provided between at least the Cu inclusive layer and the Mo inclusive layer.