Abstract: Methods and systems are disclosed for processing a precursor material. The method includes introducing a substrate having a precursor material deposited on a surface of the substrate into a first zone of a vacuum chamber. The precursor material comprises copper, indium, and at least one of gallium, selenium, sulfur, sodium, antimony, boron, aluminum, and silver. The method further includes, within the first zone, heating the precursor material to a target reaction temperature within a range of about 270° C. to about 490° C. The method further includes maintaining a selenium vapor in a second zone of the vacuum chamber, and after heating the precursor material to the target reaction temperature, introducing the precursor material and the substrate to the second zone of the vacuum chamber.

Abstract: Methods and systems are disclosed for monitoring vapor in a vacuum reactor apparatus. An system has (a) a vacuum chamber, (b) a vapor source housed in the vacuum chamber, wherein the vapor source is configured to generate a vapor, (c) a reaction vessel housed in the vacuum chamber and coupled to the vapor source, where the reaction vessel has an outlet to the vacuum chamber, and where the reaction vessel is configured to receive the vapor from the vapor source and to emit a portion of the received vapor into the vacuum chamber through the outlet, and (d) one or more sensors housed in the vacuum chamber, where the one or more sensors are configured to detect the vapor emitted through the outlet.