Physics Talk

Guillom assumed (based on copyright claims): https://commons.wikimedia.org/wiki/File:N-doped_Si.svg In Part 1 ( https://phys-talk.blogspot.com/2020/07/semiconductors-part-1-introduction-band.html ), we looked at the basics of semiconductors, using band theory to visualise how they differ from insulators and conductors. From Part 1, we learned that silicon is classed as a semiconductor due to the small energy gap between the valence and conduction bands. However, the conductivity of pure silicon is low and therefore it is not very useful in electronics. Doping is a method implemented to alter the properties of a semiconductor and modify its conductivity. It involves adding impurities to an intrinsic semiconductor (like silicon) to ‘generate either a surplus or a deficiency in valence electrons.’ [1] This imbalance allows for the movement of electrons through the material and therefore current can flow. N-type semiconductors This diagram shows the structure of doped Silicon: Phosp