The module consists of two equal parts. In the first part, the module will cover the quantum mechanical aspects of carrier transport in semiconductors. It will give answers to questions such as what are electrons and holes and why are their masses different? We will also have a brief look at how temperature can affect the transport processes. We will quickly review the law of the junction and how junctions change the classical transport process concepts. In the second part of the module the concepts of the solid state physics covered in the first part will be applied to standard devices including a quick revision of the pn diode and a deeper analysis of BJTs and MOSFETs. Small signal (briefly) and large signal analysis will be covered demonstrating that delays in devices are closely related to the type of carriers and the quality of the material. We will also briefly introduce more advanced devices such as the HBT, the finFET and the IGBT.

At the end of the module, you will be able to:
1) Explain the quantum mechanical principles of semiconductors
2) Apply your knowledge of the different transport processes to predict carrier behaviour
3) Analyse the operation of different devices
4) Distinguish diffusion driven from drift driven processes and illustrate how that impacts on the devices’ response time to external stimuli
5) Solve the transport equations by making appropriate decisions on approximations
6) Describe the operation of some modern devices

Part 1 Solid State Physics of Semiconductor materials – Zahid Durrani – 10 hrs - Electrons and holes - Energy band diagrams/nearly free electron model/ effective masses - Fermi-Dirac statistics and density of electrons and holes - Workfunction and electron affinity - Generation and recombination of carriers and Law of mass action - Energy band diagram across junctions and the law of the junction - Transport processes as a function of carrier gradients (diffusion), temperature gradients (diffusion), electric fields (drift), tunnelling processes (thermionic, thermionic field emission and field emission) Part 2 Semiconductor Devices – Kristel Fobelets – 10 hrs - Schottky barrier vs Ohmic contact - pn diode - MOSFET - Operation of devices and derivation of the characteristics - Parasitics in signal devices - Large signal switching and delays - Modern devices: HBT and finFETs for small signals + IGBT for power applications