(JP8002916-A)      A new method of producing ABC2-type chalcopyrite thin films(A is Cu or Ag, B is In, Ga, or Al, C is s, Se, or Te), comprising the steps: (1) a thin film contg. excess amt. of A element, B element, and C element is formed on a heated substrate; (2) the thin film is exposed to the gas or flux which contains B and C elements or excess B, A, and C elements; (3) the physical properties of the thin film which change corresponding to the A/B ratio is monitored. The physical properties give anomalous changes when the A/B ratio changes from the values where the A element is excess to the stoichiometric value of ABC2 and they give saturated values where the B element becomes excess.    USE/ADVANTAGE -   For producing ABC2 type chalcopyrite thin films. They are used for thin film solar cells. Chalcopyrite thin films can be produced in a simper manner with good reproducibility.    (US5725671-A)      A thin film of ABC2 chalcopyrite (A = Cu or Ag, B = In, Ga or Al and C = S, Se or Te) is formed by: forming a thin layer of ABC where A is in stoichiometric excess over ABC2; exposing to a gas contg. B and C, or A, B and C with B in excess; and monitoring a property of the film which displays a satd. value when ABC2 is formed. The property monitored is electrical resistance, intensity of reflected light, or intensity of transmitted IR.    The appts. is also claimed and comprises a heated substrate holder; means for supplying A, B and C source gases; and means for monitoring the physical property of the film during the deposition process.    USE -   In prodn. of e.g. thin-film solar cells etc.    ADVANTAGE -   Method has good throughput and reproducibility and is generally superior to prior art bilayer processes.    (JP3202886-B2)      A thin film of ABC2 chalcopyrite (A = Cu or Ag, B = In, Ga or Al and C = S, Se or Te) is formed by: forming a thin layer of ABC where A is in stoichiometric excess over ABC2; exposing to a gas contg. B and C, or A, B and C with B in excess; and monitoring a property of the film which displays a satd. value when ABC2 is formed. The property monitored is electrical resistance, intensity of reflected light, or intensity of transmitted IR.    The appts. is also claimed and comprises a heated substrate holder; means for supplying A, B and C source gases; and means for monitoring the physical property of the film during the deposition process.    USE -   In prodn. of e.g. thin-film solar cells etc.    ADVANTAGE -   Method has good throughput and reproducibility and is generally superior to prior art bilayer processes.