Copper indium gallium selenide

Copper indium gallium selenide

CIGS unit cell. Red = Cu, yellow = Se, blue = In/Ga
Identifiers
CAS Number	12018-95-0(CuInSe2)
ChemSpider	24774055 Y[<del.> chemspider]
Properties
Chemical formula	CuIn1−xGaxSe2
Density	~5.7 g/cm3
Melting point	1,070 to 990 °C (1,960 to 1,810 °F; 1,340 to 1,260 K) (x = 0–1)[1]
Band gap	1.0–1.7 eV (x = 0–1)[1]
Structure
Crystal structure	tetragonal, Pearson symbol tI16 [1]
Space group	I42d
Lattice constant	a = 0.56–0.58 nm (x = 0–1), c = 1.10–1.15 nm (x = 0–1)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Copper indium gallium (di)selenide (CIGS) is a I-III-VI₂ semiconductor material composed of copper, indium, gallium, and selenium. The material is a solid solution of copper indium selenide (often abbreviated "CIS") and copper gallium selenide. It has a chemical formula of CuIn_1−xGa_xSe₂, where the value of x can vary from 0 (pure copper indium selenide) to 1 (pure copper gallium selenide). CIGS is a tetrahedrally bonded semiconductor, with the chalcopyrite crystal structure, and a bandgap varying continuously with x from about 1.0 eV (for copper indium selenide) to about 1.7 eV (for copper gallium selenide).