SYNTHESIS AND PROCESSING OF A CU-IN-GA-SE SPUTTERING TARGET

Formation of a homogeneous nanocrystalline CuIn0.7Ga0.3Se2 alloy was a chieved by mechanical alloying of blended elemental Cu, In, Ga, and Se powders in a planetary ball mill. X-ray diffraction and transmission electron microscopy techniques were employed to follow the alloy forma tion during the milling process. It was observed that, depending upon the milling conditions, either a metastable cubic or a stable tetragon al phase was produced. The grain size of the mechanically alloyed powd er was about 10 nm. The mechanically alloyed powder was consolidated t o full density by hot isostatic pressing the powder at 750 degrees C a nd 100 MPa for 2 h. Irrespective of the nature of the phase in the sta rting powder, the hot isostatically pressed compact contained the well -recrystallized tetragonal CuIn0.7Ga0.3Se2 phase with a grain size of about 50 nm. (C) 1998 Elsevier Science S.A. All rights reserved.