From the data in Table, calculate the mean value and variance in the number of electron-hole pairs created by the loss of 450 keV of particle energy in germanium and in silicon.

 

Table 11.1 Properties of Intrinsic Silicon and Germanium Si Ge Atomic number 14 32 Atomic weight 28.09 72.60 Stable isotope mass numbers 28-29-30 70-72-73-74-76 Density (300 K); g/cm 2.33 5.32 Atoms/em 4.96 x 102 4.41 x 10 Dielectric constant (relative to vacuum) 12 16 Forbidden energy gap (300 K): eV 1.115 0.665 Forbidden energy gap (0 K): eV 1.165 0,746 Intrinsic carrier density (300 K); cm 1.5 x 1010 2.4 x 10 Intrinsic resistivity (300 K); N cm 2.3 x 10, 47 Electron mobility (300 K): cm2/ V s Hole mobility (300 K); cm?/V s 1350 3900 480 N900 Electron mobility (77 K); cm/ V s 2.1 X 10 3.6 x 10 Hole mobility (77 K); cm/V -s 1.1 X 10 4.2 x 104 Energy per electron-hole pair (300 K); eV 3,62 Energy per electron-hole pair (77 K); eV 3.76 2.96 Fano factor (77 K) 0.143 (Ref. 7) 0.129 (Ref. 9) 0.084 (Ref. 8) 0.08 (Ref. 10) 0.085