FABRICATION AND CHARACTERIZATION OF SPRAY PYROLYSED In_XS_Y THIN FILMS FOR CuInS_2 SOLAR CELLS

摘要

Indium sulphide thin films were prepared at different substrate temperatures and indium to sulphur ratio [In/S] using spray pyrolysis from indium (iii) chloride and thiourea precursor solution. The films were characterised using X-ray diffraction (XRD), optical absorption and electrical measurements. All the films showed preferred orientation along the (220) direction. There was energy gap modification when the indium to sulphur ratio [In/S] was adjusted from 2/3 (2.4 eV) with shift towards higher energy for higher values. The energy gap increased with substrate temperature for films prepared within the temperature range of 483K to 705K. Electrical resistivity measured at 300 K decreased with increasing substrate temperature from 1.16×10~2 Ω cm at 483 K to 1.62 × 10~0 Ω cm at 705 K. In_2S_3 prepared at intermediate temperature showed high potential for use as buffer layers in photovoltaic heterojunction devices.