Bandgaps (Electrical Properties of Materials #11)
What is so special about silicon? Why are some materials more conductive to electricity than others? Where does static electricity come from? This 14-video lecture series introduces electronics from a materials perspective, and is based on a course which all freshman engineering students take at the National University of Singapore.
In this video:
01:54 Energy levels change when atoms approach one another
02:33 How bound electrons can become mobile
03:20 The origin of electrical conductivity
04:22 Why glass is an insulator
04:49 Energy levels in a silicon crystal
07:48 Valence and conduction bands
11:04 How heating something changes its conductivity
13:55 Definition of a valence hole
15:31 Why an electron has a higher mobility than a hole
17:16 Comparison of bandgaps of NaF, NaCl, diamond, Si, and Ge
17:57 Why some materials are transparent and others are not
Nearly 70 additional practice problems are available in the MOOC version of this course, along with supplemental videos:
https://www.edx.org/course/electronic...
Aaron Danner is a professor in the Department of Electrical and Computer Engineering at the National University of Singapore.
http://danner.group
Videos were filmed by NUS Centre for Instructional Technology with additional editing by Cheryl Lim.
@randomcheryl
