Abstract: In one embodiment, a method includes depositing a CZT(S, Se) precursor layer onto a substrate, introducing a source-material layer comprising Sn(S, Se) into proximity with the precursor layer, and annealing the precursor layer in proximity with the source-material layer in a constrained volume.

Abstract: In one embodiment, a method includes depositing a CIGS precursor layer onto a substrate, introducing a source-material layer into proximity with the precursor layer, where the source-material layer includes one or more of Cu, In, or Ga, and one or more of S or Se, and annealing the precursor layer in proximity with of the source-material layer, where the annealing is performed in a constrained volume, and where the presence of the source-material layer reduces decomposition of volatile species from the precursor layer during annealing.

Abstract: In one embodiment, a method includes depositing a chalcogenide precursor layer onto a substrate, introducing a cover into proximity with the precursor layer, and annealing the precursor layer in proximity with of the cover, where the annealing is performed in a constrained volume, and where the presence of the cover reduces decomposition of volatile species from the precursor layer during annealing.

Abstract: In one embodiment, a photovoltaic cell comprises a transparent substrate having an exposed bottom surface for receiving light; a transparent-conducting-oxide layer positioned over the transparent substrate; a chalcogenide photovoltaic-absorber layer positioned over transparent-conducting oxide layer; and another transparent-conducting-oxide layer positioned over the photovoltaic-absorber layer, where the photovoltaic cell is operable to transmit incident light to both sides of the photovoltaic-absorber layer and to absorb incident light at both the top side and the bottom side of the photovoltaic-absorber layer.

Abstract: In one embodiment, a method includes depositing a CZT(S, Se) precursor layer onto a substrate, introducing a source-material layer comprising Sn(S, Se) into proximity with the precursor layer, and annealing the precursor layer in proximity with the source-material layer in a constrained volume.

Abstract: In one embodiment, a method includes depositing a chalcogenide precursor layer onto a substrate, introducing a cover into proximity with the precursor layer, and annealing the precursor layer in proximity with of the cover, where the annealing is performed in a constrained volume, and where the presence of the cover reduces decomposition of volatile species from the precursor layer during annealing.

Abstract: In one embodiment, a method includes depositing a precursor material outwardly from a substrate, introducing a source-material into proximity with the precursor material, depositing a dopant, and annealing the precursor layer in proximity with of the source-material layer. The precursor material may include Cu, Zn, and Sn, and one or more of S or Se. The source material may include Sn and one or more of S or Se. The dopant may be deposited in sufficient proximity to the precursor material such that the average grain size of the precursor material is increased by the presence of the dopant and is greater than 200 nm. The annealing of the precursor material may be performed in a constrained volume.

Abstract: In one embodiment, a method includes depositing a CZT(S, Se) precursor layer onto a substrate and then annealing the precursor layer in the presence of a gaseous phase comprising Sn(S, Se), where the partial pressure of each component of the gaseous phase is kept approximately constant over substantially all of the surface of the precursor layer.

Abstract: In one embodiment, a method includes depositing a CIGS precursor layer onto a substrate, introducing a source-material layer into proximity with the precursor layer, where the source-material layer includes one or more of Cu, In, or Ga, and one or more of S or Se, and annealing the precursor layer in proximity with of the source-material layer, where the annealing is performed in a constrained volume, and where the presence of the source-material layer reduces decomposition of volatile species from the precursor layer during annealing.