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(not "ideal diode")
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majority carrier diffusion
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Homework #2 (Fall 2012)
A Schottky junction is formed between n-type Si with ND = 5  1016 cm3 and a metal
with a workfunction of 4.40 eV.
Use the depletion approximation and assume the Schottky model (i.e. no surface states,
no surface dipoles) to find the built-in potential (i.e. band bending), the barrier height,
and the depletion width. Plot the carrier density, potential, and electric field vs. the depth
x.
You may assume the following parameters:
Electron affinity of Si:
4.05 eV
Band gap of Si:
1.10 eV
Use the above solution as your initial “guess”, and solve the carrier density, potential, and
electric field profiles numerically using the self consistence method. Plot your results
together with the above approximate profiles under the depletion approximation.
You may use your favorite generic numeric software, write a program in your favorite
language, or even simply an Excel spreadsheet.
Device simulators are NOT allowed.