The high cost of monocrystalline and poly-crystalline silicon (c-Si) solar cells has led the solar industry to search for cheaper alternative technologies, such as thin film-based devices. In particular, devices made using hydrogenated amorphous (a-Si:H) and micro-crystalline silicon (uc-Si:H) have become a popular class of thin film solar cells thanks to the abundant availability of non-toxic raw materials; mature, low temperature process technology; and high energy yield. In addition, thin film silicon-based devices use as little as 1% of the raw material required for crystalline Si cells, while production technology may be shared with other compatible processes, such as in the manufacture of Liquid Crystal Displays [1]. Thus production costs can be significantly lowered.