Semiconductor Constants

This section includes information on properities of silicon, germanium, gallium arsenide, and other semiconductors.

1. Properties of Si

   1. Crystal Properties
      Atoms/cm3	5.0e22
      Atomic weight	28.086
      Crystal structure	Diamond
      Density	~3e5
      Lattice Constant	5.4310 A
      Band structure Properties
      Dielectric constant	11.9
      Eff. Density of states (conduction, Nc)	2.8e19 cm-3
      Eff. Density of states (valence, Nv	1.04e19 cm-3
      Electron affinity	4.05
      Minimum Indirect Energy Gap (300K)	1.12 eV
      Minimum Direct Energy Gap	3.4 eV
      Intrinsic Carrier concentration	1.45e10 cm-3
      Intrinsic Debye length	24 um
      Intrinsic resistivity	2.3e5 ohm-cm
      Minority carrier lifetime	2.5e-3 s
      Mobility (drift) (cm2/V-s)	1500(electron);450(hole)
      Thermal Properties
      Linear coefficient of thermal expansion	2.6e-6 (degC-1)
      Melting point	1414 degC (estimated)
      Boiling Point	2878degC
      Specific heat	0.7 J/g-degC
      Thermal conductivity @ 300K	1.5 W/cm-degC
      Thermal diffusivity	0.99 cm2/s
      Vapor Pressure (Pa)	1@1650degC; 1e-6@900degC
      Other Properties
      Hardness	1150 kg/mm2
      Compressibility coefficient	1.0 cm2/dyne
      Bulk modulus	9.8 dyne/cm2
      Young’s modulus	1.3 dyne/cm2
      Coefficient of thermal expansion	2.33 /degC
      dn/dT	1.2 degC
      Elastic constant, C11	1.656 dyne/cm2
      Elastic constant, C12	0.639 dyne/cm2
      Elastic constant, C44	0.795 dyne/cm2
      Breaking strength, compression	4900-5600 Kg/cm2
      Rupture modulus, bending	700-3500 Kg/cm2

2. Properties of Ge

   1. Crystal structure	Diamond
      Auger recombination coefficient	10-30 cm6/s
      Debye temperature	374 K
      Density	5.3234 g/cm3
      Dielectric constant	16.2
      Effective electron masses ml	1.6mo
      Effective electron masses mt	0.08mo
      Effective hole masses mh	0.33mo
      Effective hole masses mlp	0.043mo
      Electron affinity	4.0 eV
      Lattice constant	5.658 A
      Optical phonon energy	0.037 eV
      Breakdown field	˜105V cm-1
      Mobility electrons	=3900 cm2 V-1s-1
      Mobility holes	=1900 cm2 V-1s-1
      Diffusion coefficient electrons	=100 cm2 s-1
      Diffusion coefficient holes	=50 cm2 s-1
      Electron thermal velocity	3.1·105m s-1
      Hole thermal velocity	1.9·105m s-1
      Infrared refractive index n	4.00
      Radiative recombination coefficient	6.4·10-14 cm3/s
      Bulk modulus	7.5·1011 dyn cm-2
      Melting point	937 °C
      Specific heat	0.31 J g-1 °C-1
      Thermal conductivity	0.58 W cm-1 °C-1
      Thermal diffusivity	0.36 cm2s-1
      Thermal expansion, linear	5.9·10-6 °C -1
      Bulk modulus	7.5·1011 dyn cm-2
      Melting point	937 °C
      Specific heat	0.31 J g-1 °C-1
      Thermal conductivity	0.58 W cm-1 °C-1
      Thermal diffusivity	0.36 cm2s-1
      Thermal expansion, linear	5.9·10-6 °C -1
      Bulk modulus	7.5·1011dyn cm-2
      Density	5.323 g cm-3
      Cleavage plane	{ 001 }
      Elastic Modulus C11	12.60·1011 dyn cm-2
      C12	4.40·1011 dyn cm-2
      C44	6.77·1011 dyn cm-2

3. Properties of GaAs

   1. Crystal structure	Zinc Blende
      de Broglie electron wavelength	240 A
      Debye temperature	360 K
      Density	5.32 g cm-3
      Dielectric constant (static )	12.9
      Dielectric constant (high frequency)	10.89
      Effective electron mass me	0.063mo
      Effective hole masses mh	0.51mo
      Effective hole masses mlp	0.082mo
      Electron affinity	4.07 eV
      Lattice constant	5.65325 A
      Optical phonon energy	0.035 eV
      Energy gap	1.424 eV
      Energy separation (EΓL) between Γ and L valleys	0.29 eV
      Energy separation (EΓX) between Γ and X valleys	0.48 eV
      Energy spin-orbital splitting	0.34 eV
      Intrinsic carrier concentration	2.1·106 cm-3
      Intrinsic resistivity	3.3·108 Ω·cm
      Effective conduction band density of states	4.7·1017 cm-3
      Effective valence band density of states	9.0·10-18 cm-3
      Breakdown field	≈4·105 V/cm
      Mobility electrons	≤8500 cm2 V-1s-1
      Mobility holes	≤400 cm2 V-1s-1
      Diffusion coefficient electrons	≤200 cm2/s
      Diffusion coefficient holes	≤10 cm2/s
      Electron thermal velocity	4.4·105 m/s
      Hole thermal velocity	1.8·105m/s
      Infrared refractive index	3.3
      Radiative recombination coefficient	7·10-10 cm3/s
      Bulk modulus	7.53·1011 dyn cm-2
      Melting point	1240 °C
      Specific heat	0.33 J g-1°C -1
      Thermal conductivity	0.55 W cm-1 °C -1
      Thermal diffusivity	0.31cm2s-1
      Thermal expansion, linear	5.73·10-6 °C -1
      Bulk modulus	7.53·1011 dyn cm-2
      Density	5.317 g cm-3
      Cleavage plane	{110}
      Piezoelectric constant	e14=-0.16 C m-2
      C11	11.90·1011 dyn/cm2
      C12	5.34·1011 dyn/cm2
      C44	5.96·1011 dyn/cm2

4. Properties of Select Binary Semiconductors

   1. Parameter				AlP	AlAs	AsSb	GaP	GaAs	GaSb	InP	InAs	InSb
      Direct Energy Gap (eV@300K)	Γ15- Γ1			3.62 (77K)	3.14	2.22	2.78	1.424	0.70	1.34	0.356	0.180
      Direct Energy Gap (eV @0K)	Eg = Ego - αT2/(T+β)		Eg	2.52	2.239	1.687	2.338	1.519	0.810	1.421	0.420	0.236
      			α (10-4eV/K)	3.18	6.0	4.97	5.771	5.405	3.78	3.63	2.50	2.99
      			β	588	408	213	372	204	94	162	75	140
      Indirect Energy Gap	Γ15- X1			2.45	2.14	1.63	2.268	1.804	1.25 (10K)	2.74	--	--
      Temperature dependence or direct and indirect energy gap	dEd/dT   dEind/dT			-3.6	-5.2   -4.0	-3.5	-4.5   -5.2	-3.9   -2.4	-3.7	-2.9   -3.7	-3.5	-2.8
      Indirect Energy Gap	Γ15- L1			--	--	--	--	1.81 (110K)	0.81	1.74	--	--
      Lattice Constant (Å)				5.467	5.660	6.136	5.4512	5.6532	6.0959	5.8687	6.0583	6.4794
      Density (gm cm-3)				2.40	3.70	4.26	4.138	5.3161	5.6137	4.81	5.667	5.7747
      Melting Point (K)				2823	2013	1338	1740	1513	985	1335	1215	800
      Coefficient of Thermal Expansion 10-6/°C (@300K)				4.5	4.9	4.0	4.5	6.86	7.75	4.75	4.52	5.37
      Thermal Conductivity (W cm-1 K-1)				0.9	0.8	0.57	0.77	0.46	0.39	0.68	0.273	0.166
      Refractive index n (near Eg)				3.03	3.18	3.4	3.45	3.65	3.82	3.41	3.52	4.00
      Dielectric constant		static ε(0)		9.8	10.06	12.04	11.1	12.91	15.69	12.61	15.15	17.7
      		high f ε(∞)		7.54	8.16	10.24	9.08	10.9	14.44	9.61	12.25	15.68
      (1/n)*(dn/dT)*(K-1) x10-5				3.5	4.6	3.5	2.5	4.5	8.2	2.7	6.5	0.12
      Elastic Compliances (10-12 cm2 dyne-1)		S11		1.090	1.070	1.696	0.973	1.176	1.582	1.650	1.945	2.443
      		S12		-0.350	-0.320	-0.562	-0.298	-0.365	-0.495	-0.594	-0.685	-0.863
      		S44		1.630	1.840	2.453	1.419	1.684	2.314	2.170	2.525	3.311

Properties of Ternary Semiconductors