SELECTIVE DISSOLUTION OF THIN ASXS100-X FILMS

The changes in the dissolution rates of exposed (V//e//x//p) and unexposed (V//u//n//e//x//p) areas of thin As//xS//1//0//0// minus //x films as well as the selectivity of the system ( gamma equals V//e//x//p/V//u//n//e//x//p) are studied as a function of the arsenic content. Aqueous solutions of K//2CO//3, Na//2CO//3, Na//3PO//4 and surfactants are used for dissolution. The arsenic content in amorphous bulk materials and in thin films is determined iodometrically. It is demonstrated that the alkaline stability of the layers increases and the surfactant acts more efficiently at higher arsenic content. Thin films consisting of As//4//2S//5//8 or As//4//5S//5//5 may be employed successfully as an inorganic photoresist, to reproduce accurately details with an edge width of 0. 1 mu m.