P Type , Zn-Doped GaAs Wafer , 2”, Test Grade -Powerway Wafer
PAM-XIAMEN provides both single crystal and polycrystalline GaAs wafer ( Gallium Arsenide ) for opto-electronics and micro-electronics industry for making LD , LED , microwave circuit and solar cell applications , the wafers is in diameter range from 2" to 6" in various thicknesses and orientations. We offer single crystal GaAs wafer produced by two main growth techniques LEC and VGF method , allowing us to provide customers the widest choice of GaAs material with high uniformity of electrical properties and excellent surface quality . Gallium Arsenide can be supplied as ingots and polished wafer, both conducting and semi-insulating GaAs wafer , mechanical grade and epi ready grade are all available . We can offer GaAs wafer with low EPD value and high surface quality suitable for your MOCVD and MBE applications. PAM-XIAMEN can produce wide range grades: prime grade, test grade, and optical grade. Please contact our engineer team for more wafer information.
(GaAs)Gallium Arsenide Wafers for LED Applications
Item | Specifications | |
Conduction Type | SC/p-type with Zn dope Available | |
Growth Method | VGF | |
Dopant | Mg | |
Wafer Diamter | 2, inch | |
Crystal Orientation | (100)2°/6°/15° off (110) | |
OF | EJ or US | |
Carrier Concentration | E19 | |
Resistivity at RT | — | |
Mobility | 1500~3000cm2/V.sec
| |
Etch Pit Density | <5000/cm2 | |
Laser Marking | upon request
| |
Surface Finish | P/E or P/P
| |
Thickness | 220~450um
| |
Epitaxy Ready | Yes | |
Package | Single wafer container or cassette |
Properties of GaAs Crystal
Properties | GaAs |
Atoms/cm3 | 4.42 x 1022 |
Atomic Weight | 144.63 |
Breakdown Field | approx. 4 x 105 |
Crystal Structure | Zincblende |
Density (g/cm3) | 5.32 |
Dielectric Constant | 13.1 |
Effective Density of States in the Conduction Band, Nc (cm-3) | 4.7 x 1017 |
Effective Density of States in the Valence Band, Nv (cm-3) | 7.0 x 1018 |
Electron Affinity (V) | 4.07 |
Energy Gap at 300K (eV) | 1.424 |
Intrinsic Carrier Concentration (cm-3) | 1.79 x 106 |
Intrinsic Debye Length (microns) | 2250 |
Intrinsic Resistivity (ohm-cm) | 108 |
Lattice Constant (angstroms) | 5.6533 |
Linear Coefficient of Thermal Expansion, | 6.86 x 10-6 |
ΔL/L/ΔT (1/deg C) | |
Melting Point (deg C) | 1238 |
Minority Carrier Lifetime (s) | approx. 10-8 |
Mobility (Drift) | 8500 |
(cm2/V-s) | |
µn, electrons | |
Mobility (Drift) | 400 |
(cm2/V-s) | |
µp, holes | |
Optical Phonon Energy (eV) | 0.035 |
Phonon Mean Free Path (angstroms) | 58 |
Specific Heat | 0.35 |
(J/g-deg C) | |
Thermal Conductivity at 300 K | 0.46 |
(W/cm-degC) | |
Thermal Diffusivity (cm2/sec) | 0.24 |
Vapor Pressure (Pa) | 100 at 1050 deg C; |
1 at 900 deg C |
Wavelength | Index |
(µm) | |
2.6 | 3.3239 |
2.8 | 3.3204 |
3 | 3.3169 |
3.2 | 3.3149 |
3.4 | 3.3129 |
3.6 | 3.3109 |
3.8 | 3.3089 |
4 | 3.3069 |
4.2 | 3.3057 |
4.4 | 3.3045 |
4.6 | 3.3034 |
4.8 | 3.3022 |
5 | 3.301 |
5.2 | 3.3001 |
5.4 | 3.2991 |
5.6 | 3.2982 |
5.8 | 3.2972 |
6 | 3.2963 |
6.2 | 3.2955 |
6.4 | 3.2947 |
6.6 | 3.2939 |
6.8 | 3.2931 |
7 | 3.2923 |
7.2 | 3.2914 |
7.4 | 3.2905 |
7.6 | 3.2896 |
7.8 | 3.2887 |
8 | 3.2878 |
8.2 | 3.2868 |
8.4 | 3.2859 |
8.6 | 3.2849 |
8.8 | 3.284 |
9 | 3.283 |
9.2 | 3.2818 |
9.4 | 3.2806 |
9.6 | 3.2794 |
9.8 | 3.2782 |
10 | 3.277 |
10.2 | 3.2761 |
10.4 | 3.2752 |
10.6 | 3.2743 |
10.8 | 3.2734 |
11 | 3.2725 |
11.2 | 3.2713 |
11.4 | 3.2701 |
11.6 | 3.269 |
11.8 | 3.2678 |
12 | 3.2666 |
12.2 | 3.2651 |
12.4 | 3.2635 |
12.6 | 3.262 |
12.8 | 3.2604 |
13 | 3.2589 |
13.2 | 3.2573 |
13.4 | 3.2557 |
13.6 | 3.2541 |
What is the GaAs Process?
GaAs wafers must be prepared prior to device fabrication. To start, they must be completely cleaned to remove any damage that might have occurred during the slicing process. The wafers are then Chemically Mechanically Polished/Plaranrized (CMP) for the final material removal stage. This allows for the attainment of super-flat mirror-like surfaces with a remaining roughness on an atomic scale. After that is completed, the wafer is ready for fabrication.
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 |
Electron Hall mobility versus temperature for different doping levels. 1. Bottom curve: Nd=5·1015cm-3; 2. Middle curve : Nd=1015cm-3; 3. Top curve : Nd=5·1015cm-3 For weakly doped GaAs at temperature close to 300 K, electron Hall mobility µH=9400(300/T) cm2 V-1 s-1 |
Electron Hall mobility versus temperature for different doping levels and degrees of compensation (high temperatures): Open circles: Nd=4Na=1.2·1017 cm-3; Open squares: Nd=4Na=1016 cm-3; Open triangles: Nd=3Na=2·1015 cm-3; Solid curve represents the calculation for pure GaAs For weakly doped GaAs at temperature close to 300 K, electron drift mobility µn=8000(300/T)2/3 cm2 V-1 s-1 |
Drift and Hall mobility versus electron concentration for different degrees of compensation T= 77 K |
Drift and Hall mobility versus electron concentration for different degrees of compensation T= 300 K |
. µn =µOH/(1+Nd·10-17)1/2, where µOH≈9400 (cm2 V-1 s-1), Nd- in cm-3
.
Temperature dependence of the Hall factor for pure n-type GaAs in a weak magnetic field |
Temperature dependence of the Hall mobility for three high-purity samples |
(cm2V-1s-1), (p - in cm-3)
For weakly doped GaAs at temperature close to 300 K, Hall mobility
µpH=400(300/T)2.3 (cm2 V-1 s-1).
The hole Hall mobility versus hole density. |
rH=1.25.
Field dependences of the electron drift velocity. Solid curve was calculated by Dashed and dotted curves are measured data, 300 K |
Field dependences of the electron drift velocity for high electric fields, 300 K. |
Field dependences of the electron drift velocity at different temperatures. |
Fraction of electrons in L and X valleys. nL and nX as a function of electric field F at 77, 160, and 300 K, Nd=0 Dotted curve - L valleys, dashed curve - X valleys. |
Mean energy E in Γ, L, and X valleys as a function of electric field F at 77, 160, and 300 K, Nd=0 Solid curve - Γ valleys, dotted curve - L valleys, dashed curve - X valleys. |
Frequency dependences of electron differential mobility. µd is real part of the differential mobility; µd*is imaginary part of differential mobility. F= 5.5 kV cm-1 |
The field dependence of longitudinal electron diffusion coefficient D||F. Solid curves 1 and 2 are theoretical calculations. Dashed curves 3, 4, and 5 are experimental data. Curve 1 - from Curve 2 - from Curve 3 - from Curve 4 - from Curve 5 - |
Field dependences of the hole drift velocity at different temperatures. |
Temperature dependence of the saturation hole velocity in high electric fields |
The field dependence of the hole diffusion coefficient. |
There are two schools of thought regarding the impact ionization in GaAs.
The first one states that impact ionization rates αi and βi for electrons and holes in GaAs are known accurately enough to distinguish such subtle details such as the anisothropy of αi and βi for different crystallographic directions. This approach is described in detail in the work by Dmitriev et al.[1987].
Experimental curves αi and βi versus 1/F for GaAs. |
Experimental curves αi and βi versus 1/F for GaAs. |
Experimental curves αi and βi versus 1/F for GaAs. |
The second school focuses on the values of αi and βi for the same electric field reported by different researches differ by an order of magnitude or more. This point of view is explained by Kyuregyan and Yurkov [1989]. According to this approach we can assume that αi = βi. Approximate formula for the field dependence of ionization rates:
αi = β i =αoexp[δ - (δ2 + (F0 / F)2)1/2]
where αo = 0.245·106 cm-1; β = 57.6 Fo = 6.65·106 V cm-1 (Kyuregyan and Yurkov [1989]).
Breakdown voltage and breakdown field versus doping density for an abrupt p-n junction. |
Pure n-type material (no ~ 1014cm-3) | |
The longest lifetime of holes | τp ~3·10-6 s |
Diffusion length Lp = (Dp·τp)1/2 | Lp ~30-50 µm. |
Pure p-type material | |
(a)Low injection level | |
The longest lifetime of electrons | τn ~ 5·10-9 s |
Diffusion length Ln = (Dn·τ n)1/2 | Ln ~10 µm |
(b) High injection level (filled traps) | |
The longest lifetime of electrons | τ ~2.5·10-7 s |
Diffusion length Ln | Ln ~ 70 µm |
Surface recombination velocity versus doping density Different experimental points correspond to different surface treatment methods. |
90 K | 1.8·10-8cm3/s |
185 K | 1.9·10-9cm3/s |
300 K | 7.2·10-10cm3/s |
300 K | ~10-30cm6/s |
500 K | ~10-29cm6/s |
Are You Looking for GaAs substrate?
PAM-XIAMEN is proud to offer indium phosphide substrate for all different kinds of projects. If you are looking for GaAs wafers, send us enquiry today to learn more about how we can work with you to get you the GaAs wafers you need for your next project. Our group team is looking forward to providing both quality products and excellent service for you!