Hi I have a question on solid state physics for BJT:

if there is big failure in processing of BJTs and there are 3 malfunctions in the devices:

1-Now the Saturation voltage is 0.7V instead of 0.25V
2-Current gain decreases quickly with increasing collector current density
3- Current gain also increases with collector current density when measured at small values of Ic (collector current).

Can you figure out the reason for those malfunctions what happened (doping error of some phenomena happened)

Can I have some help please to figure this problem??

thank you

This post has been edited by brad sue on Apr 3 2011, 01:54 PM