材料期刊网

High quality AgGaSe2 single crystals with 20 mm in diameter and 55 mm in length have been grown by Bridgman technique. It is found that there is a second phase of Ag-rich Ga2Se3 (or named AgGa7Se11) in the AgGaSe2 crystal. It is concluded by discussions with the DTA results and the phase diagram that single crystals grown from polycrystalline materials with stoichiometric composition must contain a second phase of Ag-rich Ga2Se3. This result is helpful for the heat treatment, in which what and how much is added and what temperature is chosen for the heat treatment, are very important.