Archives

Solar cells work by using materials that absorb photons from sunlight in a broad spectral range and in turn effectively convert this captured light into free charges that produce electricity. Modern solar cells are based on crystalline Silicon (c-Si) which is a cheap and abundant semiconductor, however the cost to produce electricity using them is relatively high as the efficiency rates of c-Si based cells are relatively low. As a result thin film solar cells have been developed to combat crystalline Silicon's inherent inefficiencies. Technologies such as CIGS, CdTE, amorphous Silicon and OPV have all strived to create solar cells that have high efficiencies coupled with good cell stability and low manufacturing costs.

ALD has been described as a thin film deposition technology that can keep the semiconductor industry on track per Moore's law (or observation) [1] for a few more years. In its most ideal form, it is a process that enables monolayer, or sub-monolayer growth of certain materials through the sequential exposure of a functionalized substrate to a pair of precursor gases. If dosed correctly the gases attach at specific surface sites and react to create a near perfect film on the order of a few angstroms thick. Presently the U.S. Department of Defense anticipates that the last process node for semiconductor devices (the end of Moore's) is 7 nm and will be achieved by 2020 [2].