ABSTRACT
The energy band structures of Si and Ge are depicted in the following (Figure A.1), together with (1) their carrier effective mass parameters (Table A.1) and (2) their bulk structural, mechanical, optical, and electrical properties (Table A.2) [1–4]. Energy band structure, showing the principal conduction and valence bands of (a) Si and (b) Ge as a function of k-space direction. https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9781315216911/9fc10d54-04ca-4e8b-af21-9892cbc5b25d/content/figa_1.tif"/> (From Shur, M., Physics of Semiconductor Devices, Prentice-Hall, Englewood Cliffs, NJ, 1990.) Carrier Effective Mass Parameters for Si and Ge
Parameter
Units
Silicon
Germanium
Effective electron mass (mn *)
(×mo )
Longitudinal (4.2 K)
0.9163
1.58
Transverse (4.2 K)
0.1905
0.082
Density of states (4.2 K)
1.062
—
Density of states (300 K)
1.090
—
Effective hole mass (mp *)
(×mo )
Heavy hole (4.2 K)
0.537
0.28
Light hole (4.2 K)
0.153
0.044
Density of states (4.2 K)
0.59
—
Density of states (300 K)
1.15
—
Properties of Bulk Si and GeParameter
Units
Silicon
Germanium
Atomic number
—
14
32
Atomic density
(atoms/cm3)
5.02 × 1022
4.42 × 1022
Atomic weight
(g/mol)
28.09
72.6
Density
(g/cm3)
2.329
5.323
Electronic orbital configuration
—
(Ne)3s 23p 2
(Ar)3d 104s 24p 2
Crystal structure
—
Diamond
Diamond
Lattice constant (298 K)
(Å)
5.43107
5.65791
Dielectric constant
—
11.7
16.2
Breakdown strength
(V/cm)
3 × 105
1 × 105
Electron affinity
(V)
4.05
4.00
Specific heat
(J/g-°C)
0.7
0.31
Melting point
(°C)
1412
1240
Intrinsic Debye length (300 K)
(μm)
24
0.68
Index of refraction
—
3.42
3.98
Transparency region
(μm)
1.1–6.5
1.8–15
Thermal conductivity (300 K)
(W/cm-°C)
1.31
0.60
Thermal expansion coefficient (300 K)
(°C−1)
2.6 × 10−6
5.9 × 10−6
Young’s modulus
(dyne/cm2)
1.9 × 1012
—
Energy bandgap (low doping)
(eV)
1.12 (300 K)
0.664 (291 K)
1.17 (77 K)
0.741 (4.2 K)
Equivalent conduction band minima
—
6
8
Effective electron mass (300 K)
(×mo )
1.18
—
Effective hole mass (300 K)
(×mo )
0.81
—
Intrinsic carrier density (300 K)
(cm−3)
1.02 × 1010
2.33 × 1013
Eff. conduction band DoS (300 K)
(cm−3)
2.8 × 1019
1.04 × 1019
Effective valence band DoS (300 K)
(cm−3)
1.04 × 1019
6.00 × 1018
Electron mobility (300 K)
(cm2/V-s)
1450
3900
Hole mobility (300 K)
(cm2/V-s)
500
1900
Electron diffusivity (300 K)
(cm2/s)
37.5
100
Hole diffusivity (300 K)
(cm2/s)
13
49
Optical phonon energy
(meV)
63
37
Phonon mean free path length
(Å)
76
105
Intrinsic resistivity (300 K)
(Ω-cm)
3.16 × 105
47.62