1. Professor Ronald L. Carter ronc@uta.edu http://www.uta.edu/ronc/
Semiconductor Device Modeling and Characterization – EE5342 Lecture 18 – Spring 2011
Professor Ronald L. Carter

2. Project Question and Answer
What questions pertinent to the project do you have?
If questions come up, be sure to see the echo link for the Q&A.
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3. Bipolar junction transistor (BJT)E B C
VEB
VCB
Charge neutral Region
Depletion Region
The BJT is a “Si sandwich” Pnp (P=p+,p=p-) or Npn (N=n+, n=n-)
BJT action: npn Forward Active when VBE > 0 and VBC < 0
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4. BJT coordinate systemsz
x”c x” WB
WB+WC
-WE xB x
x’E x’
Charge neutral Region
Depletion Region
Base
Collector
Emitter
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5. BJT boundary and injection cond (npn)
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6. BJT boundary and injection cond (npn)
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7. IC npn BJT (*Fig 9.2a)
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8. References
1 OrCAD PSpice A/D Manual, Version 9.1, November, 1999, OrCAD, Inc.
2 Semiconductor Device Modeling with SPICE, 2nd ed., by Massobrio and Antognetti, McGraw Hill, NY, 1993.
* Semiconductor Physics & Devices, by Donald A. Neamen, Irwin, Chicago, 1997.
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