Typically, devices are fabricated from metallic thin films or etched semiconductor layers.
The typical photocell consists of a light-sensitive semiconductor layer, sandwiched between two electrodes.
For the type I heterostructures the bottom of the conduction band and the top of the valence subband are formed in the same semiconductor layer.
A typical cell has two semiconductor layers.
Finally, an aluminium coating is applied which is partly evaporated using a mask, leaving behind the interconnections between components formed in the semiconductor layer.
The semiconductor layer is then patterned to the accelerometer's geometry.
This semiconductor layer has one or more apertures so that the underlying mass will have the corresponding apertures.
A mass in the cavity is supported in cantilever fashion by the piezoresistant arms of the semiconductor layer.
The oxidation is especially problematic for semiconductor layers containing aluminium.
June 1, 2011-Researchers demonstrated a method that could produce cheaper semiconductor layers for solar cells.