24 ℃和0.1～900 MPa压力下乙醇的拉曼光谱研究

在24℃和0.1~900MPa压力下测量了含50%水的乙醇溶液和纯乙醇的激光拉曼光谱。研究结果表明,纯乙醇和50%乙醇溶液中的C—H基团振动波数均随压力的增大而增大,它们的各振动峰与压力的关系分别为:纯乙醇:ν1=2881.890 0.00127P 6.213×10-6P2;ν2=2928.707 0.00438P 4.772×10-6P2;ν3=2973.457 0.00889P 3.245×10-6P2;50%乙醇溶液:ν1=2885.616 0.0108P-2.699×10-6P2;ν2=2932.734 0.0137P-3.346×10-6P2;ν3=2978.115 0.0165P-4.914×10-6P2。另外,还观察到在低于550MPa压力范围,50%乙醇溶液中的氢键强度随压力的增大而明显增加,550MPa以上压力时不再随压力而发生变化。     

Effect of interface roughness on the carrier transport in germanium MOSFETs investigated by Monte Carlo method

Interface roughness strongly influences the performance of germanium metal-organic-semiconductor field effect transistors(MOSFETs).In this paper,a 2D full-band Monte Carlo simulator is used to study the impact of interface roughness scattering on electron and hole transport properties in long-and short-channel Ge MOSFETs inversion layers.The carrier effective mobility in the channel of Ge MOSFETs and the in non-equilibrium transport properties are investigated.Results show that both electron and hole mobility are strongly influenced by interface roughness scattering.The output curves for 50 nm channel-length double gate n and p Ge MOSFET show that the drive currents of n-and p-Ge MOSFETs have significant improvement compared with that of Si n-and p-MOSFETs with smooth interface between channel and gate dielectric.The 82% and 96% drive current enhancement are obtained for the n-and p-MOSFETs with the completely smooth interface.However,the enhancement decreases sharply with the increase of interface roughness.With the very rough interface,the drive currents of Ge MOSFETs are even less than that of Si MOSFETs.Moreover,the significant velocity overshoot also has been found in Ge MOSFETs.