DESIGN THEORY OF JUNCTION TRANSISTORS 



1299 



Appendix A 



1.0 GENERAL 



This study is an extension of Shockley's analysis of the junction tran- 

 sistor to include high-frequency effects and the voltage dependence of 

 base-layer thickness. Shockley's paper* and the later paper by Shockley, 

 Sparks, and Tealf contain the following of interest here: 



(a) analysis of the dc steady state of a junction transistor*; 



(b) analysis of the low-frequency small-signal parameters Ve , a, Cc*t; 

 and 



(c) analysis of frequency dependence of the transport factor /Sf. 



In addition to repeating the above, this study gives these new results: 



(a) analysis of steady-state small-signal ac operation [dc biases pres- 

 ent] ; and 



(b) the small-signal ac short-circuit admittances yee , ijce , Vee , and 



Vcc- 

 1.1 ASSUMPTIONS 



Semiconductor. 



The p-n-p type structure assumed is shown in Fig. 6. The emitter, 

 base, and collector regions may each be characterized by a resistivity 

 and a minority carrier diffusion length. The emitter, collector, and base 

 contacts have no effect on the currents which flow at the junctions. 

 Injected carriers pass through the base layer by diffusion and through 



EMITTER 



BASE 



COLLECTOR 



X 

 X= 



Fig. 6 — jp-n-p junction transistor. 



* W. Shocklej^ The Theory of -p-n Junctions in Semiconductors and p-n Junc- 

 tion Transistors, B.S.T.J., 28, p. 435. 



t W. Shockley, M. Sparks, and G. K. Teal, The p-n Junction Transistors, Phys. 

 Rev., 83, p. 151, July, 1951. 



