Non-ohmic contact resistance and field-effect mobility in nanocrystalline silicon thin film transistors
Publication Type:Journal Article
Source:APPLIED PHYSICS LETTERS, Volume 93, Issue 16, p.163503 (2008)
Contact resistance has a significant impact on the electrical characteristics of thin film transistors. It limits their maximum on-current and affects their subsequent behavior with bias. This distorts the extracted device parameters, in particular, the field-effect mobility. This letter presents a method capable of accounting for both the non-ohmic (nonlinear) and ohmic (linear) contact resistance effects solely based upon terminal I-V measurements. Applying our analysis to a nanocrystalline silicon thin film transistor, we demonstrate that contact resistance effects can lead to a twofold underestimation of the field-effect mobility.