Microcrystalline silicon thin-film transistors for large area electronic applications

Thin-film transistors (TFTs) based on microcrystalline silicon (c-Si: H) exhibit high charge carrier mobilities exceeding 35 cm(2) V-1 s(-1). The devices are fabricated by plasma-enhanced chemical vapor deposition at substrate temperatures below 200 degrees C. The fabrication process of the mu c-S:H TFTs is similar to the low temperature fabrication of amorphous silicon TFTs. The electrical characteristics of the mu c-Si:H-based transistors will be presented. As the device charge carrier mobility of short channel TFTs is limited by the contacts, the influence of the drain and source contacts on the device parameters including the device charge carrier mobility and the device threshold voltage will be discussed. The experimental data will be described by a modified standard transistor model which accounts for the contact effects. Furthermore, the transmission line method was used to extract the device parameters including the contact resistance. The modified standard transistor model and the transmission line method will be compared in terms of the extracted device parameters and contact resistances.