Abstract
Ternary Ag-In-Se alloys are promising photovoltaic materials. The liquidus projection and the 450 °C isothermal section of the ternary Ag-In-Se system are determined. The primary solidification phases include three terminal solid solution phases, (Ag), (In), and (Se), nine binary intermediate phases, β-(Ag 3 In), ζ-(Ag 3 In), γ-(Ag 9 In 4 ), φ-(AgIn 2 ), β-(Ag 2 Se), In 2 Se 3 , In 6 Se 7 , InSe, and In 4 Se 3 , and two ternary compounds, AgInSe 2 and AgIn 5 Se 8 . There are fourteen invariant reactions involving liquid, and seven of them are experimentally determined in this study. The reactions with the highest and lowest reaction temperatures are L + (Ag)虠 AgInSe 2 + β-(Ag 2 Se) at 631.7 °C and L虠 φ-(AgIn 2 ) + InSe + (In) at 142.8 °C, respectively. In the 450 °C isothermal section, there are eleven tie-triangles, which are (Ag) + β-(Ag 2 Se) + AgInSe 2 , (Ag) + AgInSe 2 + InSe, (Ag) + ζ-(Ag 3 In) + InSe, ζ-(Ag 3 In) + InSe + Liquid, In 4 Se 3 + InSe + Liquid, AgInSe 2 + InSe + AgIn 5 Se 8 , InSe + In 6 Se 7 + AgIn 5 Se 8 , AgIn 5 Se 8 + In 6 Se 7 + In 2 Se 3 , AgIn 5 Se 8 + In 2 Se 3 + Liquid, AgInSe 2 + AgIn 5 Se 8 + Liquid and β-(Ag 2 Se) + AgInSe 2 + Liquid.