-What can happen when you shine light greater than the bandgap on a semiconductor?
-What does the minority carrier lifetime represent?
-How do you calculate G, the generation rate?
-Why does a photodetector use the minority carrier current?
-Think up some real world examples of diffusion (like the perfume example given in the book).
-Why is the particles move randomly is their net motion (diffusion) in one direction (from high to low concentrations)?
-Review the derivation of Fick's First Law.
-Write out the equations for G. Why is there a negative there (hint plug in the slope- concentration over distance and use what you know about the results of diffusion)?
-J is a flux. What are the units of flux?
-What do you need to get electrons and holes to "drift"?
-Study equations 5.37 and 5.38. Be able to identify which term is caused by electron drift and which by electron diffusion.
-How are the diffusion coefficient and drift mobility related?
*Apply your knowledge: Figure out the drift and diffusion fluxes for a forward biased pn junction.
-What does steady state mean?
-Review the derivation of the continuity equation. Where was Fick's First Law needed? How did t end up in it?
*Apply your knowledge: why does this derivation only work for an infinitely long sample?
Important terms you should know
-diffusion
-flux
-Einstein relation
-Built in potential
Go to the textbook website and check out these solved problems (in the "Solved Problems" section.