EE212spring2010HW2 - Middle East Technical University...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Middle East Technical University Electrical and Electronics Engineering Department EE 212- Semiconductor Devices and Modeling Spring 2010-2011 Homework Set-2 1) Carriers move toward regions of --------- concentration. 2) Diffusion current densities are proportional to the (list all) ………………………………………………………………………………… 3) Which of the following is wrong when temperature is increased? i) Thermal energy increases ii) Generation rate stays constant iii) Electron concentration increases and hole concentration decreases iv) Eventually thermal equilibrium is achieved a) i and ii b) iii c) iv d) ii and iii e) all of them 4) How does the hole recombination lifetime change with increasing donor impurity in an n-type semiconductor? Explain qualitatively. 5) Why is the recombination rate equal to the generation rate under steady-state conditions? Explain qualitatively. 6) What are the wavelengths in nm of photons that can excite an electron from valance to conduction band for the following semiconductors? Si, Ge, GaAs, InP, GaN.
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

EE212spring2010HW2 - Middle East Technical University...

This preview shows document pages 1 - 2. Sign up to view the full document.

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