for intraband scattering, while
-1 - -I mi3/2
- (2)+
t ij Tji ij
x
C 2 2Tij(2)] } y3/21/2 (3.9)
C t
for interband scattering. In the split-off band, the scattering relaxation time is given by
ac3 T T T (3.10)
In these equations
k3/2a2 m3/2
1 p0 am0 (3.11)
T x 42_7TI4P C 2z
yi. Di D' b/a, a and b are valence band acoustic deformation
potential constants in the Picus and Bir [44] notation, ps is the density, CP and Ct are the longitudinal and transverse sound velocities in silicon and Lij and Tij are functions of and Yij defined in [43].
3.4 Optical Phonon Scattering
Optical phonon scattering, while negligible at very low temperatures, cannot be ignored at high temperatures. Ehrenreich and Overhauser [45] have calculated the mobility of holes in silicon and its dependence on temperature. The calculated mobility follows a T2.3 dependence for reasonable choices of the parameters which described the