Journal ArticleDOI
A theory of transistor cutoff frequency (f T ) falloff at high current densities
Reads0
Chats0
TLDR
In this paper, it was shown that the observed falloff in the f T of a transistor at high currents is due to the spreading of the neutral base layer into the collector region of the device at high current densities.Abstract:
It is shown that the observed falloff in the f T of a transistor at high currents is due to the spreading of the neutral base layer into the collector region of the device at high current densities. The base layer spreading mechanism derives from an analysis of the effect of the current-dependent buildup of the mobile-carrier space-charge density in the collector transition layer. Calculations show that at sufficiently high collector current levels, the mobile space-charge density in the collector transition layer cannot be considered negligible in comparison to the fixed charge density of that region. The over-all effect of taking the mobile space charge into account in analyzing the collector transition region is that, at high current densities, the transition region boundary adjacent to the neutral base layer is displaced toward the collector metal contact with increasing collector current. The attendant widening of the neutral base layer results in the observed, high-current falloff in f T . The application of this theory to transistor structures of both the alloy and mesa variety yields, in each case, calculated curves of f T vs I c which are in reasonably good agreement with experiment.read more
Citations
More filters
Journal ArticleDOI
L5 system: Ultralinear transistors
TL;DR: In this paper, a family of ultralinear npn transistors has been developed for use in the L5 coaxial-carrier system, which is characterized by extremely low distortion and noise figure.
Journal ArticleDOI
A curve-fitted circuits model for bipolar transistor f/SUB T/ roll-off at high injection levels
TL;DR: A simple empirical relationship is introduced for modelling the common-emitter short-circuit gain-bandwidth product (f/SUB T/) of bipolar transistors operated in high-injection regimes to within an error of no more than 20 percent.
Journal ArticleDOI
Arsenic-spike epilayer technology applied to bipolar transistors
TL;DR: In this article, an epilayer with an arsenic-doped spike of 50 nm width has been grown and used in silicon bipolar junction transistors (BJTs), where the collector-base junction of the BJT is formed within the arsenic spike.
Journal ArticleDOI
Device Characterization for Computer Analysis of Large Circuits
TL;DR: In this article, the selection of transistor models can be incorporated into the computer simulation of circuit behavior, so that each model chosen provides the best accuracy-simplicity compromise for the circuit environment in which each transistor resides.
Journal ArticleDOI
Characteristics and Scaling Properties of N-P-N Transistors with a Sidewall Base Contact Structure
TL;DR: It is shown that the current gain and transconductance will be lowered in scaled down transistors and upward characteristics will be improved more than downward characteristics.
References
More filters
Journal ArticleDOI
The theory of p-n junctions in semiconductors and p-n junction transistors
TL;DR: The theory of potential distribution and rectification for p-n junctions is developed with emphasis on germanium, resulting in an admittance for a simple case varying as (1 + iωτ p )1/2 where τ p is the lifetime of a hole in the n-region.
Journal ArticleDOI
Mobility of Holes and Electrons in High Electric Fields
TL;DR: In this paper, the field dependence of mobility has been determined for electrons and holes in both germanium and silicon, and the observed critical field at 298\ifmmode^\circ\else\textdegree\fi{}K beyond which $\ensuremath{\mu}$ varies as ${E}^{-}\frac{1}{2}}$.
Journal ArticleDOI
The Dependence of Transistor Parameters on the Distribution of Base Layer Resistivity
J. L. Moll,I. M. Ross +1 more
TL;DR: In this article, a method of analyzing transistor behavior for any base-layer impurity distribution is presented, in particular expressions for emitter efficiency, transverse sheet resistance R, transit time, and frequency cut-off f?.
Journal ArticleDOI
Structure-Determined Gain-Band Product of Junction Triode Transistors
TL;DR: In this article, the authors compared the power gain of the junction triode with those of the field effect transistor and the analog transistor and showed that the gain-band product is nearly independent of the particular alpha cutoff frequency selected.