Channel thickness of thin-film transistors (TFTs) having amorphous In-Ga-Zn oxide channels has been optimized based on the device performance characteristics including output characteristics, transfer characteristics, and bias stress stability. The device performance initially improved as the channel thickness increased from 20 to 30 nm, but subsequently deteriorated with further increasing thickness to 40 nm. The 30-nm-channel TFT exhibited threshold voltage close to 0 V, the highest field-effect mobility (μFE), highest on/off ratio, and smallest threshold voltage shift under bias stress. The observed channel-thickness-dependent changes in device characteristics are attributed to the collective contribution of interface traps, fixed oxide charges, and mobile charges.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry