NONAQUEOUS CHEMICAL BATH DEPOSITION OF BI2S3 THIN-FILMS

A method for preparation of Bi2S3 thin films from a nonaqueous medium is developed. In brief, Bi(NO3)3 and Na2S2O3 are dissolved in acetic a cid glacial and formaldehyde, respectively, to prepare equimolar (0.1 M) solutions. Bi2S3 films are deposited at room temperature. Character isation of the prepared films was carried out with XRD, optical absorp tion, dark resistivity and thermoelectric e.m.f. measurements and scan ning electron microscopy. These studies reveal that the as-deposited f ilms are amorphous, have an optical band gap (direct) of 1.9 eV, and a re n-type in nature. The electrical resistivity is of the order of 10( 6) ohm cm.