In the current work, in situ surface passivation Ge substrate by using trimethylaluminum(TMA) prior to HfTiO films deposition and electrical properties of HfTiO/Ge gate stacks have been investigated by X-ray photoel...In the current work, in situ surface passivation Ge substrate by using trimethylaluminum(TMA) prior to HfTiO films deposition and electrical properties of HfTiO/Ge gate stacks have been investigated by X-ray photoelectron spectroscopy(XPS) and electrical measurements systematically. Based on analysis from XPS measurements, it has been confirmed that the interfacial layer of HfTiO/Ge gate stack has been suppressed effectively after 20 half-ALD cycles TMA pretreatment. Electrical properties of metal-oxidesemiconductor(MOS) capacitor based on HfTiO gate dielectrics have shown that the MOS capacitor with20 cycles TMA cleaning exhibits the lowest interface state density(~7.56 eV^(-1)cm^(-2)) and the smallest leakage current(~2.67 × 10^(-5)A/cm^2). Correspondingly, the leakage current conduction mechanisms for MOS capacitor device with 20 cycles TMA cleaning also have been discussed in detail.展开更多
基金support from the National Natural Science Foundation of China (Nos. 51572002, 11474284)the Technology Foundation for Selected Overseas Chinese Scholar,Ministry of Personnel of China (No. J05015131)the Anhui Provincial Natural Science Foundation (No. 1608085MA06)
文摘In the current work, in situ surface passivation Ge substrate by using trimethylaluminum(TMA) prior to HfTiO films deposition and electrical properties of HfTiO/Ge gate stacks have been investigated by X-ray photoelectron spectroscopy(XPS) and electrical measurements systematically. Based on analysis from XPS measurements, it has been confirmed that the interfacial layer of HfTiO/Ge gate stack has been suppressed effectively after 20 half-ALD cycles TMA pretreatment. Electrical properties of metal-oxidesemiconductor(MOS) capacitor based on HfTiO gate dielectrics have shown that the MOS capacitor with20 cycles TMA cleaning exhibits the lowest interface state density(~7.56 eV^(-1)cm^(-2)) and the smallest leakage current(~2.67 × 10^(-5)A/cm^2). Correspondingly, the leakage current conduction mechanisms for MOS capacitor device with 20 cycles TMA cleaning also have been discussed in detail.