ECE Purdue Semiconductor Fundamentals L4.2a: Carrier Transport - Drift Current

Table of Contents available below.


This video is part of the course "Semiconductor Fundamentals" taught by Mark Lundstrom at Purdue University. The course can be found on nanoHUB.org at https://nanohub.org/courses/sfun or on edX at https://www.edx.org/course/semiconduc... .

This course provides the essential foundations required to understand the operation of semiconductor devices such as transistors, diodes, solar cells, light-emitting devices, and more. The material will primarily appeal to electrical engineering students whose interests are in applications of semiconductor devices in circuits and systems. The treatment is physical and intuitive, and not heavily mathematical.


Technology users will gain an understanding of the semiconductor physics that is the basis for devices. Semiconductor technology developers may find it a useful starting point for diving deeper into condensed matter physics, statistical mechanics, thermodynamics, and materials science. The course presents an electrical engineering perspective on semiconductors, but those in other fields may find it a useful introduction to the approach that has guided the development of semiconductor technology for the past 50+ years.


Table of Contents:
00:00 Lecture 4.2a: Drift Current
00:38 Topics
01:04 Semiconductor in equilibrium
02:51 Semiconductor under bias
03:42 Drift current and drift velocity
05:56 Velocity and electric field
06:39 Velocity and electric field
09:07 Drift velocities in Si
10:35 Drift vs. thermal velocities
11:21 Drift current equations
12:00 Mobility vs. doping
12:47 Ionized impurity scattering
13:33 Crystal lattice at T = 0 K
13:57 Lattice scattering
14:26 Mobility vs. temperature
15:49 Mathiessen's rule
16:37 Velocity vs. electric field
18:56 Velocity vs. electric field
20:07 Current, conductivity, resistivity
21:31 Resistivity vs. doping density
22:14 Our first semiconductor device: The resistor
23:41 Topics
24:01 Relation to general current equation?
24:25 Gradients in the QFL and electric field
25:21 Summary