a thin - film solar cell is provided . the thin - film solar cell comprises a flexible metallic substrate having a first surface and a second surface . a back metal contact layer is deposited on the first surface of the flexible metallic substrate . a semiconductor absorber layer is deposited on the back metal contact . a photoactive film deposited on the semiconductor absorber layer forms a heterojunction structure and a grid contact deposited on the heterjunction structure . the flexible metal substrate can be constructed of either aluminium or stainless steel . furthermore , a method of constructing a solar cell is provided . the method comprises providing an aluminum substrate , depositing a semiconductor absorber layer on the aluminum substrate , and insulating the aluminum substrate from the semiconductor absorber layer to inhibit reaction between the aluminum substrate and the semiconductor absorber layer .