Thin film semiconductor solar cell array and method of making

Abstract

A method of forming laser-patterned conductive elements on a thin film of semiconductor material in a semiconductor device by fabricating a thin film of metal on the semiconductor material and scribing the semiconductor film along a desired pattern with a laser operated at a power density sufficient to ablate the semiconductor material along the desired pattern. The ablation of the semiconductor material produces gases that structurally weaken and burst through the metal film along the desired pattern to form gaps separating the metal film into a plurality of conductive elements, for example, back electrodes on a thin-film photovoltaic module. In a second embodiment, a method of forming a multi-cell thin-film semiconductor device with laser-patterned back electrodes includes the steps of fabricating a plurality of spaced-apart front electrodes on a substrate, fabricating a thin film of semiconductor material on the front electrodes, fabricating a thin film of metal on the semiconductor film, and scribing the metal film along a pattern of lines with a laser operated at a power density sufficient to melt the metal through the underlying semiconductor film and form electrical connections between the metal film and the front electrodes along the scribe lines. Multi-cell, thin-film amorphous silicon photovoltaic modules having back electrodes formed by the above methods also are disclosed.