HIGHLY PHOTOSENSITIVE CDSE COATINGS BY SCREEN PRINTING AND SINTERING TECHNIQUE

CdSe powder precipitated from a chemical bath was screen printed on gl ass substrates using ZnCl2 as flux, with flux to powder ratio (FPR) va rying in the range of 0.1 to 0.5 by weight, and propylene glycol as bi nder. After a subsequent sintering in air for 1 h at 450 degrees C, th e screen printed coatings showed a photocurrent to darkcurrent ratio o f similar to 10(8) under tungsten halogen illumination of 2000 W m(-2) . X-ray diffraction studies showed that sintering causes the conversio n of the ZnCl2 flux into hexagonal phase ZnO which would hh the void a mong the CdSe particles. The optimum FPR and the sintering temperature to achieve maximum photosensitivity in the coatings are presented. Th e coatings may be used in the development of highly photosensitive lig ht dependent resistors. (C) 1996 American Institute of Physics.