ELEG 646; ELEG 446- Nanoelectronic Device Principles– Spring 2011Homework #8 - due Friday, 15 April 2011, in class1. A. symmetrical abrupt Ge p-n junction has dopant concentrations of 1015atoms cm-3on both sides. Calculate the avalanche breakdown voltage if the maximum field at breakdown is 2.5 x105V/cm. Hint: Careful to use Ge materials data rather than Si. 2. In the problem (1) above for Ge with doping impurity concentration NI= 1015cm-3, compare your breakdown voltage with the value obtained by using the following universal (but approximate) expression breakdown voltage for materials with different bandgaps: BV(volts) = 60(Eg/1.1)3/2(NI/1016)-3/4. Here Egis in eV, and NIis in cm-3. Is this “universal” expression useful? 3. Problem 4.13 in chapter 4, Muller & Kamins, p. 224 in 3rd edition. Hint: In the discussion following Eq. 4.4.20, there is a discussion in the text of current (10 mA), atomic density (5E22 cm-3), etc. Use the data and the equations in this section to determine the tunneling probability, then work back to find the L,
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