Contour anode photodissolution of film semiconductor CdS material

Electrochemical behaviour of thin light-sensitive films of CdS has been studied in dark and during illumination in the solutions of Na2SO4, Na2SO4+H2O2, and NaCl. The current of anodic dissolution has been calculated with taking into account the Rose model providing for levels of recombination of two types. It is shown that light sensitivity of the films in the solution of Na2SO4 is caused by generation of the holes in a layer of the space charge. High currents of anodic dissolution and a decrease of photoconductivity in NaCl solution are due to a high adsorption of Cl ion responsible for re-charging of the surface. The possibility of contour etching on the film at the expense of anodic dissolution upon illumination is shown