Extraction of Contact Resistance and DC Modeling in Metal Oxide TFTs

Abstract

Based on the device physics, a simple and fast method of extracting contact resistance in metal oxide thin-film transistors (MOTFTs) is proposed through the I-V characteristics. This method divides the channel into two parts: the contact channel and the intrinsic channel, and assumes the electrons injected into the active layer at the source side are completed in the line injection. Using the I-V characteristics, the contact voltage can be obtained, and then the contact resistance can be extracted. The results indicate that contact resistance in MOTFTs depends on V g , V d , and L. Applying the extraction results, a dc drain current model considering contact resistance is proposed. Using this model, we can accurately describe the measurements of MOTFTs with channel lengths scaling from 50 μ m to 10 μ m. Through the extensive comparisons between the model results and the numerical iteration or experimental data, the validity of the method is strongly supported. This extraction method uses non-numerical iteration, which is simple, fast, and accurate.