Department of Physics, Unit Catalogue 2007/08 |
PH20015 Semiconductor physics |
| Credits: 3 |
| Level: Intermediate |
| Semester: 2 |
| Assessment: EX 100% |
| Requisites: |
| Before taking this unit you must take PH10007 and take PH10008 and take PH20029 and while taking this unit you must take PH20017 |
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Aims: The aims of this unit are to explore some of the physics underlying the behaviour of electrons in semiconductor materials and the operation of simple semiconductor devices.
Learning Outcomes: After taking this unit the student should be able to: * discuss the basic concepts of semiconductor physics; * calculate carrier concentrations and effective masses; * outline the basic principles of semiconductor device operation; * describe the interactions between electrons and photons such as absorption, spontaneous emission and stimulated emission; * give examples of common optoelectronic devices for emitting, detecting and modulating light, and explain their physical principles of operation. Skills: Numeracy T/F A, Problem Solving T/F A. Content: Basic properties of semiconductors (4 hours): Electrons and holes and their effective masses. Extrinsic and intrinsic semiconductors; donors and acceptors. Electron and hole concentrations, semiconductor statistics. Transport properties (2 hours): Electrical conduction and scattering of electrons and holes in solids. Drift velocity, resistivity, diffusion, electron-hole recombination, recombination length. The Hall effect. The p-n junction (2 hours): The unbiased p-n junction; junction formation, depletion layer width. Biased p-n junctions; band profiles, depletion region width, junction capacitance. Balance of drift and diffusion currents. Qualitatitive introduction to the ideal diode equation, reverse bias breakdown. Electron-photon interaction in semiconductors (3 hours): Optical absorption in bulk semiconductors; spectral dependence, photocurrent, P-I-N photodiodes. Optical emission in semiconductors; radiative and non-radiative transitions, light-emitting diodes. |