Zhang Jiaqi, Zhang Yi, Chen Dazheng, Zhu Weidong, Xi He, Zhang Jincheng, Zhang Chunfu, Hao Yue
State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology, School of Microelectronics, Xidian University, 2 South Taibai Road, Xi'an 710071, China.
Nanomaterials (Basel). 2018 Dec 16;8(12):1060. doi: 10.3390/nano8121060.
Bendable single crystal silicon nanomembrane thin film transistors (SiNMs TFTs), employing a simple method which can improve the metal/n-Silicon (Si) contact characteristics by inserting the titanium dioxide (TiO₂) interlayer deposited by atomic layer deposition (ALD) at a low temperature (90 °C), are fabricated on ITO/PET flexible substrates. Current-voltage characteristics of titanium (Ti)/insertion layer (IL)/n-Si structures demonstrates that they are typically ohmic contacts. X-ray photoelectron spectroscopy (XPS) results determines that TiO₂ is oxygen-vacancies rich, which may dope TiO₂ and contribute to a lower resistance. By inserting TiO₂ between Ti and n-Si, I of bendable single crystal SiNMs TFTs increases 3⁻10 times than those without the TiO₂ insertion layer. The fabricated bendable devices show superior flexible properties. The TFTs, whose electrical properties keeps almost unchanged in 800 cycles bending with a bending radius of 0.75 cm, obtains the durability in bending test. All of the results confirm that it is a promising method to insert the TiO₂ interlayer for improving the Metal/n-Si ohmic contact in fabrication of bendable single crystal SiNMs TFTs.
采用一种简单方法制造了可弯曲的单晶硅纳米膜薄膜晶体管（SiNMs TFTs），该方法通过在低温（90°C）下插入通过原子层沉积（ALD）沉积的二氧化钛（TiO₂）中间层来改善金属/n-硅（Si）的接触特性，这些晶体管被制造在ITO/PET柔性基板上。钛（Ti）/插入层（IL）/n-硅结构的电流-电压特性表明它们通常是欧姆接触。X射线光电子能谱（XPS）结果确定TiO₂富含氧空位，这可能会使TiO₂掺杂并有助于降低电阻。通过在Ti和n-硅之间插入TiO₂，可弯曲单晶硅纳米膜薄膜晶体管的电流比没有TiO₂插入层的晶体管增加了3至10倍。所制造的可弯曲器件显示出优异的柔性特性。在弯曲半径为0.75厘米的800次弯曲中，其电学性能几乎保持不变的薄膜晶体管在弯曲测试中获得了耐久性。所有结果证实，在可弯曲单晶硅纳米膜薄膜晶体管的制造中插入TiO₂中间层是改善金属/n-硅欧姆接触的一种有前景的方法。
