High-Performance ALD Al-Doped ZnO Thin-Film Transistors Grown on Flexible Substrates

摘要

We report a CMOS compatible high-performance ALD Al-doped ZnO thin-film transistor (TFT) fabricated on flexible substrate with a sub-150 degrees C processing temperature. The TFTs channel are optimized through Al doping (2-3 at.%) using all low-temperature steps to enable flexible substrate processing while minimizing the piezoelectric effect in the channel. The optimized device has an electron mobility as high as similar to 30 cm(2)/Vs in comparison to earlier reported values of 0.1-0.7 cm(2)/Vs for ZnO TFTs while maintaining desired threshold voltages of 1-2 V and I-ON/I-OFF ratios of 10(7)-10(9).