Extraction of the Channel Mobility in InGaZnO TFTs Using Multifrequency Capacitance–Voltage Method

In this letter, we propose a mobility-extraction method using the frequency-independent capacitances extracted from the multifrequency capacitance-voltage method in amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs). This method does not use the long-channel metal-oxide-semiconductor field-effect transistor (MOSFET) current-voltage ( I-V) model and can include the effect of subgap states on the calculation of the mobility. Considering that the I-V characteristics of the disordered semiconductor transistor do not exactly follow those of the long-channel MOSFET model and the subgap states significantly affect the electrical behavior of the disordered semiconductor transistors, the proposed method is expected to be useful in the extraction of the exact values of the mobilities in disordered semiconductor transistors including a-IGZO TFTs.