Effect of TMGa flux on GaN films deposited on Ti coated on glass substrates at low temperature

Highly c-axis-oriented GaN films were deposited on Ti coated glass substrates using low temperature electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition system(ECR-PEMOCVD)with trimethyl gallium(TMGa)as gallium source.The influence of TMGa flux on the properties of GaN films were systematically investigated by reflection high energy electron diffraction(RHEED),X-ray diffraction analysis(XRD),atomic force microscopy(AFM)and Raman scattering.The GaN film with small surface roughness and high c-axis preferred orientation was successfully achieved at the optimized TMGa flux of 1.0 sccm.The ohmic contact characteristic between GaN and Ti layer was clearly demonstrated by the near-linear current-voltage(I-V)curve.The GaN/Ti/glass structure has great potential to dramatically improve the scalability and reduce the cost of solid-state lighting light emitting diodes.

基底及电解液对TiO_2纳米管阵列形貌的影响

通过中频脉冲磁控溅射的方法在ITO玻璃上沉积出致密的钛薄膜,分别以钛膜和钛箔为基底,在甘油和乙二醇为主的电解液体系中制备出TiO_2纳米管阵列,考察阳极氧化电压对纳米管形貌的影响,采用XRD、FESEM等测试手段对样品的组成、结构及形貌等进行表征。结果表明:氧化电压的增加会导致TiO_2纳米管管径和长度的增加,但氧化电压过高会造成钛箔基底TiO_2纳米管的坍塌,而ITO玻璃基钛膜上则会形成纳米深孔结构。