EC 203 SOLID STATE DEVICES KTU MODAL QUESTIONS FOR SECOND YEAR S3
APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
SOLID STATE DEVICES QUESTION PAPERS
(Answer All Questions)
1. Derive an expression for the electron current in the n-type material of a forward biased p-n junction?
2. Define diffusion length of a hole? Mention the relation between carrier life time and diffusion length of hole?
3. Define luminescence? Mention different types of luminescence?
4. For a P+N junction diode, which region is heavily doped? Also prove with suitable equations, which region among P side depletion region or N side depletion will be greater?
5. Draw the energy band diagrams for a PN junction in a) equilibrium b) Forward biased c) Reverse biased cases?
(Answer Any Two Questions)
6. Derive the continuity equation?
7. Explain the quasi Fermi level with suitable equations and figures?
8. Derive the diode equation?
9. An abrupt Si p-n junction has Na=10^18 cm^-3 on one side and Nd=5*10^15 cm^-3 on the other side.
The junction has a circular cross section with diameter of 10μm.
Calculate contact potential, Xno, Xpo, depletionregion
width(W), Q+ and €o(electric field)? Given Ɛr=11.8, Ɛ0=8.854*10^-14.