The invention provides a film having a composition Ag.sub.wCu.sub.1-wIn.sub.rGa.sub.xK.sub.ySe.sub.2(1-z)Q.sub.2z; wherein K is Al or Tl or a combination of these; Q is S or Te or a combination of these; w is in a range from 0.01 to 0.75; x is in a range from 0.1 to 0.8; and r, y and z are each independently in a range from 0 to 1, provided that r+x+y=1. Methods of making the film can include processing temperatures not exceeding 500.degree. C.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
 The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. ADJ-1-30630-12, awarded by the U.S. Department of Energy.