ECE474S09_Lecture28 - ECE 474: Principles of Electronic...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
ECE 474: Principles of Electronic Devices Prof. Virginia Ayres Electrical & Computer Engineering Michigan State University ayresv@msu.edu
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Lecture 28: Chp. 04: Current State-of-Art Transistors Photo-generated carriers Find α r for “low level injection” Excess carriers Diffusion and Drift Current Einstein’s relation Find built-in E (x) and n(x)
Background image of page 2
Lecture 28: Chp. 04: Current State-of-Art Transistors Photo-generated carriers Find α r for “low level injection” Excess carriers Diffusion and Drift Current Einstein’s relation Find built-in E (x) and n(x)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Example in Lecture 25: Try to evaluate the constant of proportionality for recombination The constant of proportionality for recombination is α r . (p. 125) Doped Si @ 300K: Majority carrier concentration: n 0 = 10 17 cm -3 Minority carrier concentration: p 0 = 2.25 x 10 3 cm -3 Doped Si @ 300K + laser light: Given: τ n = τ p = 1 μ sec. n = 101 x 10 17 cm -3 => increase factor: 10 2 p ≈ 100 x 10 17 cm -3 => increase factor: 10 16 δ n = g op τ n = (10 25 cm -3 s -1 )(1 x 10
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/26/2010 for the course ELECTRICAL ECE474 taught by Professor Tran-le,j during the Spring '10 term at Michigan State University.

Page1 / 33

ECE474S09_Lecture28 - ECE 474: Principles of Electronic...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online