Amorphous silicon

Amorphous silicon (a-Si) is the non-crystalline form of silicon used to create solar cells in solar panels and thin-film transistors in LCDs.

Used as semiconductor material for a-Si solar cells, or thin-film silicon solar cells, it is deposited in thin films onto a variety of flexible substrates, such as glass, metal and plastic. Amorphous silicon cells generally feature low efficiency.

Amorphous silicon is a second-generation thin-film solar cell technology. Although its share of the worldwide photovoltaic market declined relative to crystalline silicon and alternative cells such as CdTe and CIGS. Amorphous silicon is still a used material for manufacturers for the thin film transistor (TFT) elements of liquid crystal displays (LCDs) and for x-ray imagers.

Amorphous silicon differs from other allotropic variations, such as monocrystalline silicon—a single crystal, and polycrystalline silicon, that consists of small grains, also known as crystallites.