Indium gallium arsenide InGaAs

In0.53Ga0.47As, indium gallium arsenide lattice-matched to indium phosphide (InP)

Indium gallium arsenide (InGaAs) is a III-V semiconductor alloy.

9 sources · Updated 2026-11-01 · CC BY 4.0

Evidence level

5 of 5

Flown or field-proven

Band gap

0.75 eV

Electron transport

10000 cm²/(V·s)

Recipe, share of the weight

  • In not statedIndium
  • Ga not statedGallium
  • As not statedArsenic

Best for

Short-wave infrared photodiodes and fibre-optic receivers that need a response from 0.9 μm to 1.7 μm (NASA 2001 report; Wikipedia)

Weakest at

Space heritage is thin: the one flight result found is an 18-month ISS exposure with no published before-and-after numbers, and no radiation dose data were found

Risk at a glance

  • People None found. No GHS hazard class found for InGaAs
  • If it fails No data. No failure risks recorded
  • Corrosion Low. The company says its InGaAs photodiodes looked intact after 18 months in orbit, but no numbers were published.

Quick facts: InGaAs

Key properties of InGaAs
PropertyValueBasis
Thermal expansion (CTE)5.66 ppm/K1 sourced value

What is the coefficient of thermal expansion of Indium gallium arsenide (InGaAs)?

Indium gallium arsenide (InGaAs) has a coefficient of thermal expansion of 5.66 ppm/K. The source and test conditions are listed in the properties table on this page.

What is Indium gallium arsenide (InGaAs) used for?

Uses recorded in the sources include Short-wave infrared focal-plane array for low light level imaging; High-speed photodiode module on the ISS (MISSE 7); Fibre-optic telecommunications photodetector.

Why it exists

Indium gallium arsenide (InGaAs) is a semiconductor alloy used mainly as a photodetector for short-wave infrared light. The composition In0.53Ga0.47As is lattice-matched to indium phosphide (InP), so it can be grown on InP substrates with little strain. It has a band gap of 0.75 eV at 295 K and a cut-off wavelength of 1.68 μm at 295 K, per Wikipedia, and a NASA 2001 report gives a 1.7 μm long-wavelength cut-off for its focal-plane array. The NASA 2001 abstract gives its spectral sensitivity range as 0.9 μm to 1.7 μm at 290 K.

Where it's used

Fibre-optic telecommunications

Wikipedia describes InGaAs photodiodes as the principal use of the alloy, as fast and sensitive photodetectors for fibre-optic telecommunications. The 2026 USGS indium chapter notes that indium phosphide substrates are used in high-speed photodetectors and laser diodes for optical communications.

Imaging in low light

A 2001 NASA report describes an InGaAs visible/SWIR focal-plane array for low light level imaging, sensitive from 0.9 μm to 1.7 μm at 290 K.

On the International Space Station

A high-speed InGaAs photodiode module spent 18 months on the ISS as part of MISSE 7. The 2017 paper reports a -3 dB bandwidth of 16.8 GHz for the module.

Recipe

In0.53Ga0.47As, indium gallium arsenide lattice-matched to indium phosphide (InP); general alloy notation GaxIn1-xAs

In0.53Ga0.47As is a ternary alloy of indium, gallium and arsenic. Per the Wikipedia composition, indium and gallium share the group III sites in the ratio 0.53 to 0.47, and each formula unit has one arsenic atom. The composition is lattice-matched to indium phosphide (InP).

What InGaAs is made of
IngredientShare of the weightWhat it does
Indium In not stated Group III element; the 0.53 share is the indium fraction in the lattice-matched composition the page uses.
Gallium Ga not stated Group III element; the 0.47 share is the gallium fraction in the same composition.
Arsenic As not stated Group V element; the alloy notation GaxIn1-xAs has one arsenic atom per formula unit.

Weight shares are as printed in the sources.

What it can do

Band gap

0.75 eV

measured

In0.53Ga0.47As has a band gap of 0.75 eV at 295 K, per the Wikipedia properties table. The same page gives the absorption edge at the same composition as 0.75 eV.

Response range

The NASA 2001 abstract gives a spectral sensitivity range of 0.9 μm to 1.7 μm at 290 K for an InGaAs/InP focal-plane array. The Wikipedia page gives a cut-off wavelength of 1.68 μm at 295 K for the same alloy.

Bandwidth

A 2017 conference abstract reports a -3 dB bandwidth of 16.8 GHz for the InGaAs photodiode module flown on the ISS. A Discovery Semiconductors receiver lists a bandwidth up to 18 GHz at 2.2 μm, per its product title.

Electron transport

10000 cm²/(V·s)

measured

The electron mobility of reasonably pure Ga0.47In0.53As is printed as 10,000 cm2/(V·s) at 295 K. The hole mobility in the same table is 250 cm2/(V·s) at 295 K.

How it compares

InGaAs is a short-wave infrared detector material, with a cut-off of 1.68 μm at 295 K (Wikipedia) and 1.7 μm (NASA 2001 abstract). The sources read for this profile give its band gap, mobility and cut-off values, but no figures for other materials, so no ranking against them is claimed here. The table below lists the three benchmarks to compare.

The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Compare every grade in the family.

Benchmarks
MeasurementInGaAs
Other measurements
Band gap, In0.53Ga0.47As0.75 eV1
Lattice parameter, In0.53Ga0.47As5.869 Å2
Electron mobility, reasonably pure Ga0.47In0.53As10000 cm²/(V·s)3
Hole mobility, In0.53Ga0.47As250 cm²/(V·s)4
Electron effective mass, relative to free electron massValue printed in the properties table (unitless)0.041 -5
Cut-off wavelength, In0.53Ga0.47As1.68 μm6
Thermal expansion coefficient, GaInAs5.66 ppm/K7

Why choose it, and why not

Good for

  • Short-wave infrared detection from 0.9 μm to 1.7 μm, per the NASA 2001 abstract.
  • Fibre-optic telecommunications photodetectors, the main use the Wikipedia page names for the alloy.

Watch out for

  • Flight heritage is one 18-month ISS exposure with no published pre-flight comparison.
  • The two cut-off figures differ slightly (1.68 μm and 1.7 μm), so quote the source and condition with each value.
  • No radiation dose, vacuum or thermal-vacuum data were found beyond that one flight.

InGaAs is a well-documented short-wave infrared detector material with a flight result on the ISS, but the sources read give no before-and-after numbers for that flight.

Technical details

For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.

Cell-level benchmarks

Values for finished cells. These vary by manufacturer, so read the conditions in the notes. Compare every grade in the family.

Cell-level benchmarks
MeasurementInGaAs
Physical and electrical
Reverse saturation current density, InGaAs/InP photodiode< 1×10^-8 A/cm²8
Temperature behavior
Temperature cycling range in orbit, InGaAs photodiode moduleRange printed in the 2017 conference abstract-157 to 121 °C
Other measurements
Shunt resistance-area product, InGaAs/InP photodiode> 1×10^6 ohm cm²9
Detectivity (D*), InGaAs photodiode> 1×10^14 cm Hz^1/2 W^-110
Spectral sensitivity range, InGaAs focal-plane arrayRange printed in the abstract0.9 to 1.7 μm11
Quantum efficiency at 0.5 μm> 15 %12
-3 dB bandwidth, InGaAs photodiode module flown on the ISS16.8 GHz13
Time on the ISS, InGaAs photodiode module (MISSE 7)18 months14
Bandwidth up to, DSC-R212 2.2 μm SWIR InGaAs receiver< 18 GHz15
Bandwidth up to, DSC2-100S 2.2 μm InGaAs photodiode< 5 GHz16

Notes

The method, full conditions and any caveat for the numbered rows above.

Notes for the numbered rows
#MeasurementMethodConditionsCaveat
1Band gap, In0.53Ga0.47AsValue printed in the properties table of the Wikipedia articlecomposition In0.53Ga0.47As, lattice-matched to InPtemperature 295 K (table heading 'Value at 295 K')—
2Lattice parameter, In0.53Ga0.47AsValue printed in the properties table of the Wikipedia articlecomposition In0.53Ga0.47As, lattice-matched to InPtemperature 295 K (table heading 'Value at 295 K')—
3Electron mobility, reasonably pure Ga0.47In0.53AsPrinted as 10,000 cm2·V−1·s−1 in the properties table; the page's text says 'approaches 10×10^3'. Unit written here as cm2/(V·s) to match the form used on this site.composition Ga0.47In0.53Astemperature 295 Kpurity reasonably pure, as the page says—
4Hole mobility, In0.53Ga0.47AsPrinted as 250 cm2·V−1·s−1 in the properties table; unit written as cm2/(V·s)composition In0.53Ga0.47As, lattice-matched to InPtemperature 295 K—
5Electron effective mass, relative to free electron mass—composition In0.53Ga0.47Astemperature 295 Kbasis m*/m0, unitless as printed—
6Cut-off wavelength, In0.53Ga0.47AsValue printed in the Materials synthesis section; the Wikipedia figure differs slightly from the NASA 2001 figure of 1.7 μm, and both are keptcomposition In0.53Ga0.47Astemperature 295 Knote the page gives the absorption edge as 0.75 eV for the same composition—
7Thermal expansion coefficient, GaInAsPrinted as 5.66×10−6 K−1 in the FCC lattice parameter section. 10⁻⁶ K⁻¹ is the same unit as ppm/K, so the number is copied unchanged.composition GaInAs (as the page names it)temperature not stated on the pageunit in source 5.66×10−6 K−1—
8Reverse saturation current density, InGaAs/InP photodiodeUpper bound printed in the abstract as 'JD < 10(exp -8) A/sq cm'composition In(.53)Ga(.47)As/InPtemperature 290 Kdevice photodiode structure described in the abstract—
9Shunt resistance-area product, InGaAs/InP photodiodeLower bound printed in the abstract as 'RoA > 10(exp 6) omega-sq cm'composition In(.53)Ga(.47)As/InPtemperature 290 K—
10Detectivity (D*), InGaAs photodiodeLower bound printed in the abstract as 'greater than 10(exp 14) cm-(square root of Hz/W)'temperature 290 Kbasis D* as printed in the abstract—
11Spectral sensitivity range, InGaAs focal-plane array—composition In(.53)Ga(.47)As/InPtemperature not stated in the abstractnote the short-wave cut-on is attributed in the abstract to absorption in the InP substrate—
12Quantum efficiency at 0.5 μmLower bound printed in the abstract as 'greater than 15% quantum efficiency at 0.5 micrometers'wavelength 0.5 μmcomposition InGaAs focal-plane array described in the abstracttemperature not stated in the abstract—
13-3 dB bandwidth, InGaAs photodiode module flown on the ISSValue printed in the 2017 conference abstract. The abstract gives no pre-flight value to compare with; the post-flight test is shown in its Fig. 1a, which gives no numbers in the text.device high-speed InGaAs photodiode module flown on the ISS (MISSE 7)measurement -3 dB bandwidth as printed in the abstract—
14Time on the ISS, InGaAs photodiode module (MISSE 7)Duration printed in the 2017 conference abstract and in the 2012 article; the article gives launch and return dateslaunch 16 November 2009return 1 June 2011mission MISSE 7—
15Bandwidth up to, DSC-R212 2.2 μm SWIR InGaAs receiverBandwidth printed in the product title on the manufacturer's featured-products listproduct DSC-R212, 2.2 Micron SWIR InGaAs Linear AGC Balanced Optical Receiverwavelength 2.2 μm—
16Bandwidth up to, DSC2-100S 2.2 μm InGaAs photodiodeBandwidth printed in the product title on the manufacturer's featured-products list (printed as 'up to 5 Ghz')product DSC2-100S, 2.2 Micron Wavelength InGaAs Photodiodewavelength 2.2 μm—

Corrosion and compatibility

What happens when it meets other materials and environments.

Corrosion and compatibility
EnvironmentConcernWhat happens
Low Earth orbit on the ISS (MISSE 7 external exposure), with UV, radiation and thermal cycling low The company says its InGaAs photodiodes looked intact after 18 months in orbit, but no numbers were published.1
Corrosion details
#EnvironmentDetailsTest conditions
1 Low Earth orbit on the ISS (MISSE 7 external exposure), with UV, radiation and thermal cycling The CEO of Discovery Semiconductors said preliminary analysis showed the photodiodes intact under UV, radiation and thermal cycling. The article gives no before-and-after measurement, and the electro-optical characteristics were still to be studied after the article was written. exposure 18 months on the ISS, launched 16 November 2009, returned 1 June 2011basis qualitative statement by the company's CEO, no measured values; rating is assigned from that wording

Risks and side effects

Hazards to people, what happens when a cell overheats, and how the material is handled and stored.

For people

No supplier safety data sheet or GHS classification for InGaAs was read. The one toxicity source is a set of rodent exposure levels from studies of InP and GaAs.

Exposure studies
Wikipedia gives the National Toxicology Program rodent exposure levels for InP and GaAs (rats 0.01, 0.1 or 1.0 mg/m3; mice 0.1, 0.5 or 1.0 mg/m3). These are study design values, not hazard classes.
Dust
No dust or inhalation hazard statement for InGaAs was found in the sources read.

In orbit

The only flight result found is one 18-month exposure of a photodiode module on the ISS.

Flight
A high-speed InGaAs photodiode module was on the ISS for 18 months, launched on 16 November 2009 and returned on 1 June 2011 (MISSE 7).
Thermal cycling
The module was cycled between -157 and +121 degC, 16 times a day, according to the 2017 conference abstract.
Result
The company's CEO said preliminary analysis showed the photodiodes intact after UV, radiation and thermal cycling. The article prints no numbers for that result.

Test details
The original wording and numbers from the sources, for readers who want them.

Supply and geography

How common the raw materials are and where they come from.

Indium

Top producers (2025)
China 70%
Critical mineral lists
US: listed, EU: not listed
Recycling
USGS: indium is most commonly recovered from ITO scrap in Japan and the Republic of Korea. Data on the quantity recovered were not available.
Substitutes
USGS: substitutes for ITO coatings include antimony tin oxide, carbon nanotubes, PEDOT and silver nanowires (these are display and touch-screen uses, not InGaAs).

Gallium

Top producers (2025)
China 99%
Critical mineral lists
US: listed, EU: listed
Recycling
USGS: old scrap is not recovered. New scrap from GaAs device manufacture is reprocessed to recover high-purity gallium at one facility in New York.

Updated