历史查询   



 为了更好的帮助您理解掌握查询词或其译词在地道英语中的实际用法，我们为您准备了出自英文原文的大量英语例句，供您参考。 
By comparing ECV results with those of secondary ion mass spectroscopy (SIMS), it is found that the dopant concentration profiles in heavilydoped p+ layer as well as junction depths measured by ECV are in good agreement with those measured by SIMS.


These toxins are usually broadspectrum and act on the central nervous system or at the neuromuscular junction.


Characteristics of the SurfaceIntrinsic Josephson Junction


Thus, the characteristics of the surface junction consisting of the surface CuO double layers remarkably differ from those of the junctions deep in the stack, which will be referred to as ordinary IJJs.


Furthermore, by shunting the surface junction resistively, we are able to observe the AC Josephson effect at 3mm waveband.

 更多 


 A general theory of injection of minority carriers in pn alloy junctions was developed by using onedimensional model. It was assumed that the recombination rate is proportional to the density of injected carriers. Two extreme cases of low injection levels and high injection levels were first considered, and the result of which was then used as the zeroorder approximation in calculating the distribution of the injected minority carriers in pn junctions. By the method of successive approximation,... A general theory of injection of minority carriers in pn alloy junctions was developed by using onedimensional model. It was assumed that the recombination rate is proportional to the density of injected carriers. Two extreme cases of low injection levels and high injection levels were first considered, and the result of which was then used as the zeroorder approximation in calculating the distribution of the injected minority carriers in pn junctions. By the method of successive approximation, an analytical expression for the relationship between the injection efficiency and the injection level (i. e. the ratio of the density of injected minority carriers to that of original majority carriers) was obtained. A similar expression for the relationship between the total current density flowing through the junction and the injection level was developed on the same basis. The results of the present theory show that for an ordinary alloy junction transistor, the injection efficiency of the emitter decreases gradually as the emitter current increases. At very high  本文用一维模型计算了pn合金结中少数载流者的一般注射理论。这里假设复合率是与注入载流者的密度成正比。首先,我们讨论了大注射和小注射的两种极端情况,这样得到的结果被用作零级近似解来计算pn结中注入少数载流者的分布情况。用逐步近似的方法我们得到了注射效率和注射强度(即注入少数载流者的密度与原有多数载流者的密度之比)间的解析关系。在同样的基础上也得到了通过结的总电流密度和注射强度间的类似关系。这理论的结果表明;对一个平常的合金结晶体三极管来说,当发射极电流增加时,发射极的注射效率逐渐下降。在很大的注射强度下,注射效率趋近于极限值1/(1+b),其中b是电子迁移率与空穴迁移率之比。对一个具有很低注射效率的pn合金结来说,在注射电流小的时候,注射效率是正比于通过结的总电流;当往射电流很大时,注射效率趋近于极限值1/(1+b)。理论结果还表明,在小注射情下,通过pn合金结的总电流是正比于注射强度;而在大注射情况下,它是正比于注射强度的平方。  An equivalent circuit of transistors operating in saturation region is suggested. This circuit contains a transistor operating in active region and a diode biased in forward direction. By using this equivalent circuit, the physical meaning of storage time of transistors may be explained more intuitively. With this, the storage time in drift transistor, Which is common base connected, has been investigated. By solving the continuity equation, the steady state and the transient components of the densities of minority... An equivalent circuit of transistors operating in saturation region is suggested. This circuit contains a transistor operating in active region and a diode biased in forward direction. By using this equivalent circuit, the physical meaning of storage time of transistors may be explained more intuitively. With this, the storage time in drift transistor, Which is common base connected, has been investigated. By solving the continuity equation, the steady state and the transient components of the densities of minority carriers in diode near the pnjunction is obtained. By setting these two components equal in magnitude and opposite in sign, we get a formula, from which the storage time may be determined. The storage time in some special cases has been calculated. The results show that the storage time depends upon the life time of minorities and the surface recombination velocities both in base region and in collector region. This may be a guide for design a transistor with more short storage time.  半导体三极管在饱和区工作时,其等效电路可以用一个三极管及一个由集电极及基极构成的二极管联成的电路表示出来,其中三极管在有源区工作,而二极管在正向偏压下工作。这样的等效电路具有比较明显的物理意义。利用这个电路来求漂移管在一个共基极电路中脉冲工作下的储存时间。解出非平衡少数载流子的连续性方程,求出二极管pn结附近非平衡少数载流子密度的稳定态分量及暂态分量,从而得到决定储存时间的方程。计算结果表明,储存时间与基极区域及集电极区域中非平衡载流子的寿命及表面复合速度有关。减少寿命及增加表面复合速度就可以减少储存时间。  In this paper the relationships between smallsignal hparameters and elements of the natural equivalent circuit of the common emitter configuration of junction transistors are studied. From experimental results of hparameters of two typieal alloyed PNP transistors (one 2N104 and one п6 transistor) the relationship of hparameters and elements of natural equivalent circuit vs operating frequency and d. c. operating condition (d.c. emitter current and d.e. collector voltage) are evaluated. Results thus... In this paper the relationships between smallsignal hparameters and elements of the natural equivalent circuit of the common emitter configuration of junction transistors are studied. From experimental results of hparameters of two typieal alloyed PNP transistors (one 2N104 and one п6 transistor) the relationship of hparameters and elements of natural equivalent circuit vs operating frequency and d. c. operating condition (d.c. emitter current and d.e. collector voltage) are evaluated. Results thus obtained ace then compared with results obtained from analysis based on calculations using physical constants of the transistor. The explanation of the behavior of the reverse opencircuit voltage amplification factor, μb0, of the common emitter circuit is given in detail. Characteristics of μbo and properties of h22 (the output admittance with input open) are correlated. This paper gives complete information about hparameters and natural equivalent circuit of two transistors, serving as an important reference for both device men and research workers on transistor circuits.  本文研究面结合型晶体管共发射极线路的小讯号h参数与自然等效线路中元件的关系。根据两种合金管(2N104及Ⅱ6晶体管)h参数的实验结果求出h参数与自然等效线路元件随频率及随直流运用状态(直流发射极电流及直流集电极电压)的相互关系。对实验结果与根据晶体管物理构造分析计算的结果进行了比较。对开路反向电压放大系数μ_(bc)的现象给予详细分析,并求出μ_(bc)与开路输出导纳h_(22)的相互关系。两套晶体管的h参数及自然等效线路的完整资料可供晶体管器件设计及线路研究者的使用。   << 更多相关文摘 
相关查询  



