Recombination life-time for electrons in p-doped silicon due to Auger recombination

a 3 body process, one electron and two holes

[1]

Auger recombination coefficient for electrons in p silicon

Substrate acceptor doping density, i.e. number of holes. This is the value for the substrate that I found in a Fabrice note that was attributed to the Strasbourg group. This is to be compared with ~10¹⁵ 1/cm³ in the epi layer

Conclusion, this life time is comparable to the collection time, so it is not unreasonable to expect a significant signal contribution from the substrate.

[1] Richard S. Muller and Theodore I. Kamins with Mansun Chan, "Device electronics for Integrated Circuits" 3rd Edition, John Wiley & Sons, Inc., 2003,

see section 5.2, p. 234-p235