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排序方式: 共有191条查询结果,搜索用时 171 毫秒
1.
Experimental evidences are given which demonstrate that degradation of the common-emitter forward current gain hFE of submicron silicon npn bipolar transistors at low reverse emitter-base junction applied voltage is caused by primary hot holes of the n+ /p emitter tunneling current rather than secondary hot electrons generated by the hot holes or thermally-generated hot electrons. Experiments also showed similar kinetic energy dependence of the generation rate of oxide/silicon interface traps by primary hot electrons and primary hot holes. Significant hFE degradation was observed at stress voltages less than 2.4 V  相似文献   
2.
We present here a self consistent theory of small amplitude double layers associated with electrostatic ion cyclotron waves in a plasma containing hot electrons, cold ions and traversed by an ion beam. It has been shown that compressive type of double layers solution exists when θb (beam temperature) < αb (beam concentration) < 1.  相似文献   
3.
Pure water has been characterized for nearly a century, by its dissociation into hydronium (H3O)1+ and hydroxide (HO)1- ions. As a chemical equilibrium reaction, the equilibrium constant, known as the ion product or the product of the equilibrium concentration of the two ion species, has been extensively measured by chemists over the liquid water temper-ature and pressure range. The experimental data have been nonlinear least-squares fitted to chemical thermodynamic-based equilibrium equations, which have been accepted as the industrial standard for 35 years. In this study, a new and statistical-physics-based water ion product equation is presented, in which, the ions are the positively charged protons and the negatively charged proton-holes or prohols. Nonlinear least squares fits of our equation to the experimental data in the 0-100 ℃ pure liquid water range, give a factor of two better precision than the 35-year industrial standard.  相似文献   
4.
The thermal capture rates of electrons and holes at zinc centers in silicon are obtained in reversed biased N+P and P+N diodes from junction capacitance transients due to capture of photogenerated and injected carriers. The electric field dependence of the thermal capture rates of holes at singly ionized zinc centers is E?1·1, while that at doubly ionized zinc centers is exp(?E/E0). The temperature dependence of the thermal capture rate of holes at doubly ionized zinc centers is small. The thermal capture rate of electrons at neutral zinc centers is 2·0×10?9cm3/sec with very little field dependences, while that at singly ionized zinc centers is 5·0×10?11cm3/sec with very little field and temperature dependence below 170°K. Auger-impact emission rate of electrons trapped at doubly ionized zinc centers by electrons is 3·5×10?10cm3/sec with very little field and temperature dependence below 170°K.  相似文献   
5.
Room temperature frequency dispersion of the admittance of Metal-Oxide-Semiconductor (MOS) capacitors made on non-degenerate n-type silicon substrate with (111) surface orientation was studied. A simplified lumped equivalent circuit model which takes into account the interface edge effect, i.e. carrier generation-recombination-trapping via interface states near the edge of the surface inversion region, is proposed and found to be in good agreement with experimental data. Our model also suggests another method of calculating the density of interface states. Fundamental properties of interface states are estimated from experimental data. A self-consistency check is made among the values of equivalent circuit elements to substantiate our model.  相似文献   
6.
A general theory is developed to obtain the spatial variations of the concentrations of the deep levels and free carrier from constant-capacitance voltage-transient (CCVT) measurements on semiconductor junctions containing many deep energy levels. In order to measure the deep-level densities near the junction boundary, two methods of edge region correction are also analyzed: the integral equation method and an experimental three-frequency capacitance-voltage method. Conditions under which these methods are easily applicable in experiments are discussed. Applications of these methods are published elsewhere.  相似文献   
7.
First order Ricatti equations are obtained for the capacitive 3-wire transmission line of a one-dimensional MOS capacitance which give an order of magnitude improvement in numerical computation time over the transmission matrix solution of the lumped section equivalent circuit model of the transmission line.  相似文献   
8.
薩支唐  揭斌斌 《半导体学报》2007,28(10):1497-1502
提出场引晶体管双极理论.替代已55年久,1952 Shockley发明单极理论.解释近来双栅纳米硅MOS晶体管实验特性--两条电子和两条空穴表面沟道,同时并存.理算晶体管输出特性和转移特性,包括实用硅基及栅氧化层厚度.理算比较最近报道实验,利用硅FinFET,含(金属/硅)和(p/n)结,源和漏接触.实验支持双极理论.建议采用单管,实现CMOS倒相电路和SRAM存储电路.  相似文献   
9.
本文描述双极场引晶体管(BiFET)飘移扩散理论,包括薄纯基上两个等同金属氧化物硅(MOS)栅.把两维晶体管分解成两个一维晶体管,以表面势为参变量,得到解析方程.提供实用硅基和氧化层厚度范围内,随直流电压变化,输出和转移电流和电导总量和飘移扩散分量.显著部分的飘移电流来自横向电场平方的纵向梯度.  相似文献   
10.
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