Browsing by Author "Ching-Yuan Wu"

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Calculation of Electron Mobility in High Fields by Path Integral Method
(交大學刊編輯委員會, 1975-07)
吳慶源
;
Ching-Yuan Wu
The mobility of elemental semiconductor is calculated for all fields up to breakdown by means of the path integral method. A self-consistent solution of the Boltzmann transport equation is obtained and analytic expressions for thr drift velocity,mobility and the relationship between electron temperature and the electric field is obtained. The validity of this calculation is limited to elemental semiconductors, such as Ge and Si at lattice temperatures high enough so that inter-valley scattering may be neglected, and the scattering is dominated by electron- phonon scattering. A comparison between theory and the experimental results for n-type and p-type Ge is made. It is found that agreement between theory and experiment is good for both n- and p-type Ge. A saturation velocity of 6.10*10^3 cm/sec between 2.1*10^3 v/cm and 5.1*10^3 v/cmis predicted for n-type Ge.
Generalized Ic vs VBE Characteristics of Bipolar Transistors
(交大學刊編輯委員會, 1975-07)
吳慶源
;
楊洛
;
Ching-Yuan Wu
;
Rock Young
A generalized IC V.S VBE Characteristics is derived for bipolar transistor (npn or pnp), which includes all the levels of carrier injection at the emitter and the impurity profiles in the base region. This generalized expression can be reduced to the conventional forms of collector current density for both low and high level current injections with arbitrary doping profiles in the base region. The degradations of minority carrier diffusivity (or mobility) due to impurity concentration and high current level injection are also considered. Comparisons of the experimental data and the theoretical results are made. Discussions and applications of the theoretical results are also given.