Complex sentence: The characteristics of a silicon based TFT depend on the crystalline state; that is, the semiconductor layer can be either amorphous silicon, microcrystalline silicon, or it can be annealed into polysilicon.
Split into simpler sentences: The characteristics of a silicon based TFT depend on the crystalline state. That is, the semiconductor layer can be either amorphous silicon, microcrystalline silicon, or it can be annealed into polysilicon.