CuInSe2 coatings prepared using solvothermal-synthesized CuInSe2 particles

► CuInSe2 coatings were sintered from its single crystalline particles. ► CuSe was used as a sintering aid. ► In2Se3 was added for compositional control. ► We show the criticalness of Se vapor supply to the sample during sintering. ► A rarely observed morphology of tetrahedron structure is also reported.