Carrier lifetime of Si, GaAs, Ge

[Henry797]

Can Anyone tell me the carrier lifetimes of Silicon, Gallium Arsenide & Germanium?

 

[dick_freebird]

Minority carrier lifetime depends hugely on doping, more
than material system itself I expect. I'd bet that there
are textbook curves out there (check the images that
Google pops up, about halfway down the search page).
SemiWiki may also have something for you.

In the kind of silicon dopings that support medium voltage
analog, I've seen uS-range collector region lifetimes. Never
had occasion to look at the others.

 

[Henry797]

Hi,
I was actually looking for the carrier lifetime (average time for the carriers to recombine which is inversely proportinal to the carrier recombination rate) of instrinsic semiconductors, not the minority carrier lifetime of doped semiconductors. In literature, I mostly found the term minority carrier lifetime, but in photoconductivity, you tend to prefer using high resistivity semiconductors, what happens then? Do you still consider it as doped material and use the term minority carrier life time? In this case I guess the carrier life time should be referred as photo-generated carrier life time. Please correct me if I'm wrong.
Many Thanks

 

[Henry797]

To Understand the difference between free-lifetime and minority carrier lifetime, please refer to the attached.

 

[dick_freebird]

I would imagine that the free lifetime would look like the
asymptote of the appropriate minority-carrier lifetime, as
N (doping based carrier concentration) goes to zero. But
there's probably something to do with temperature (thermal
generation raising N) in intrinsic material. And of course a
slab of intrinsic material is in itself not too useful, and what
necessarily abuts it may strongly affect recombination &
lifetime in nearby regions.