what is temperature inversion

[pandit_vlsi]

temperature inversion asic

hi all.
i want to know about temperature inversion.
plz dont say that as temp/ increses delay decreses in 90 nm and below.
plz elaborate.
pandit

 

[uma_vlsi]

asic temperature inversion

With increase in temperature, the free electrons acquire more energy and start to travel faster inside the pn-junction. this causes a decrease in delay.

this is relative though. i still need to confirm why its not possible for the electrons bound in a bond to impede the flow of free electrons. this scenario is possible due to lattice vibrations of the bound electrons due to increase in temperature.