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 Ge

Parameter

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