Semiconductor Devices

Aim

The course aims to familiarize the student with fundamental principles of semiconductor devices, to understand and connect fundamental material properties to the electrical and optical characteristics of semiconductor devices. After completing the course, the student should be able to:

• explain concepts such as bandgap, energy level, mobility, effective mass, charge generation and recombination, doping, drift, diffusion, equilibrium and steady state.
• understand and apply relationship between bandgap, energy level, mobility, effective mass, charge generation and recombination, doping, operation, diffusion, equilibrium and steady state, conductivity, current density, temperature and illumination in semiconductors.
• calculate and determine material parameters (band gap, doping, minority carrie lifetime, diffusion length) based on electrical characteristics of the semiconductor components.
• design pn junction, Schottky diode, bipolar transistor, MOSFET and pn solar cells according to given characteristics.
• calculate device parameters such as built-in potential in pn-junctions, amplification of transistors, bass transport factor and emitter efficiency in BJT, flat band and threshold voltage in MOSFET.

Content

Basic semiconductor physics, concept and mechanisms such as band diagram, valence- and conduction band, Fermi level, Fermi-Dirac statistics, band gap, effective mass, drift, diffusion, doping, intrinsic, extrinsic, electron-hole pair, charge generation and recombination, minority carriers, majority carriers etc. will be discussed thoroughly. Function and modelling of pn-junctions, contact potential, depletion region, and different break down mechanisms for pn-junctions will be explained. Functions and I-V characteristics of some other devices such as MOSFET and bipolar transistors will also be discussed. Laboratory assignment includes classical labs with diode and transistor measurements.