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The behaviors of lead zirconate titanate (PZT) deposited as the dielectric for high-voltage devices are investigated experimentally and theoretically. The devices demonstrate not only high breakdown voltages above 350 V, but also excellent memory behaviors. A drain current-gate voltage (ID-VG) memory window of about 2.2 V is obtained at the sweep voltages of ±10 V for the 350-V laterally diffused metal oxide semiconductor (LDMOS). The retention time of about 270 s is recorded for the LDMOS through a controlled ID-VG measurement. The LDMOS with memory behaviors has potential to be applied in future power conversion circuits to boost the performance of the energy conversion system. 相似文献
73.
对叠放在水平面上的两个物体在水平方向拉力作用下是否做相对运动问题进行了探讨, 提出了临界
拉力、 临界加速度的概念, 导出判断是否相对运动的条件 相似文献
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The one-dimensional super-symmetric ferromagnetic t-J model is studied via the thermal Bethe ansatz.Analytic expressions of the free energy for T→O are obtained.A new critical behaviour beyond the universal class of Luttinger Liquids is found in this system. 相似文献
76.
A Novel Contactless Method for Characterization of Semiconductors:Surface Electron Bean Induced Voltage in Scanning Electron Microscopy 下载免费PDF全文
We present a novel contactless and nondestructive method called the surface electron beam induced voltage (SEBIV) method for characterizing semiconductor materials and devices.The SEBIV method is based on the detection of the surface potential induced by electron beams of scanning electron microscopy (SEM).The core part of the SEBIV detection set-up is a circular metal detector placed above the sample surface.The capacitance between the circular detector and whole surface of the sample is estimated to be about 0.64pf.It is large enough for the detection of the induced surface potential.The irradiation mode of electron beam (e-beam) influences the signal generation When the e-beam irradiates on the surface of semiconductors continuously,a differential signal is obtained.The real distribution of surface potentials can be obtained when a pulsed e-beam with a fixed frequency is used for irradiation and a lock-in amplifier is employed for detection.The polarity of induced potential depends on the structure of potential barriers and surface states of samples.The contrast of SEBIV images in SEM changes with irradiation time and e-beam intensity. 相似文献
77.
A Compact Vircator with Feedback Annulus Operated in Quasi—Single TM01 Mode Within the C Band 总被引:9,自引:0,他引:9 下载免费PDF全文
An axially extracted virtual cathode oscillator(vircator)with a feedback annulus is proposed and configured through particle-in-cell simulation.This compact device needs no guiding magnetic field.Its experimentally radiated microwave is measured to be of quasi-single TM01 mode with a frequency range of 4.41-4.69GHz and a power level of above 300MW,when the diode voltage ranges between 400-480kV and the beam current 20-25kA;this confirms the simulation results. 相似文献
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空心阴极灯激发的微波等离子体炬原子/离子荧光光谱研究--钙的原子/离子荧光光谱 总被引:2,自引:0,他引:2
用强短脉冲供电技术的空心阴极灯作激发源、微波等离子体炬作原子/离子化器,建立了原子/离子荧光光谱实验装置。详细研究了微波等离子体功率、观察高度、空心阴极灯电流等因素对原子/离子荧光信号强度的影响,测量了系统对Ca的原子/离子荧光光谱的检出限。 相似文献
80.