please help me i'm an electronic stud

Please give some information about these DIODE, their CONSTRUCTION, OPERATION and CONSTRUCTION.

*TUNNEL DIODE
*VARACTOR DIODE
*PIN DIODE
*IMPATT DIODE
*HOT CARRIER DIODE

YOU CAN E-MAIL ME AT lorie_c_m@yahoo.com

THANK YOU VERY MUCH

homework question?

the best thing for you to do is to refer a book..........possibly integrated electronics by millman and halkais..........has everything

cheers.
ashwath