Amorphous silicon (a-Si) AKA Thin Film. Jenny Gould and Alec Stall. What is amorphous silicon (a-Si)?. A semiconductor material only a few micrometers thick, attached to an inexpensive backing such as glass, flexible plastic, or stainless steel.
Amorphous silicon absorbs solar radiation 40 times more efficiently than does single-crystal silicon, so a film only about 1 micron (one one-millionth of a meter) thick can absorb 90% of the usable solar energy
Can be produced at a lower temperature and can be deposited on low-cost substrates
Amorphous silicon has no crystal structure and is gradually degraded by exposure to light through the Staebler-Wronski Effect.
Combined with some start-up problems with encapsulation and quality control, the poor outdoor performance of a-Si products has, until recently, defined the reputation of thin films.Pros and Cons