Properties of CuInSe₂ Thin Films Prepared by Chemical Spray Pyrolysis

Abstract

CuInSe 2 thin films have been prepared by chemical spray pyrolysis (CSP). Effects of substrate temperature ( T s ), pH and the ion ratio (Cu/In) in the spray solution on the film properties have been investigated, and the following results have been obtained; (i) films deposited with neutralized solution (pH=4.0) exhibited chalcopyrite structure in contrast to those deposited with unneutralized one (pH=1.9) having sphalerite structure, (ii) resistivity increased with T s for films deposited with the unneutralized solution, while decrease of the resistivity was observed for the neutralized case, and (iii) remarkable increase of resistivity with decreasing Cu/In has been observed. Finally, the effect of pH on the rectifying property in the CuInSe 2 /CdS heterojunction has been presented.