Nanocrystalline silicon

Most materials with grains in the micrometre range are actually fine-grained polysilicon, so nanocrystalline silicon is a better term.

The crystalline volume fraction (as measured from Raman spectroscopy) is another criterion to describe the materials in this transition zone.

nc-Si has many useful advantages over a-Si, one being that if grown properly it can have a higher electron mobility, due to the presence of the silicon crystallites.

It also shows increased absorption in the red and infrared wavelengths, which make it an important material for use in a-Si solar cells.

One of the most important advantages of nanocrystalline silicon, however, is that it has increased stability over a-Si, one of the reasons being because of its lower hydrogen concentration.