{
  "spore": "profile",
  "id": "indium-gallium-arsenide",
  "spore_version": "0.2",
  "family": "semiconductor-materials",
  "name": "Indium gallium arsenide",
  "abbreviation": "InGaAs",
  "role": "photodetector",
  "category": "semiconductors",
  "type": "inp",
  "summary": "Indium gallium arsenide (InGaAs) is a III-V semiconductor alloy. The Wikipedia composition In0.53Ga0.47As is lattice-matched to indium phosphide (InP), with a band gap of 0.75 eV and a lattice constant of 5.869 Å at 295 K. A 2001 NASA report describes an In(.53)Ga(.47)As/InP focal-plane array that responds from 0.9 μm to 1.7 μm at 290 K. A high-speed InGaAs photodiode module from Discovery Semiconductors spent 18 months on the International Space Station (MISSE 7, 16 November 2009 to 1 June 2011). Its 2017 conference abstract reports a -3 dB bandwidth of 16.8 GHz, but no pre-flight figure is printed in any source read for this profile.\n",
  "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",
  "identity": {
    "formula": "In0.53Ga0.47As, indium gallium arsenide lattice-matched to indium phosphide (InP); general alloy notation GaxIn1-xAs",
    "designations": [],
    "source": "wiki-ingaas",
    "where": "Section 2 (Materials synthesis) and Section 4.1 (Properties table), composition stated for Ga0.47In0.53As; no CAS number, space group or density printed on the page"
  },
  "tags": {
    "environments": [
      "low-earth-orbit"
    ],
    "stresses": [
      "uv-exposure",
      "radiation",
      "thermal-cycling"
    ],
    "applications": [
      "optics-and-cameras",
      "electronics-and-chips",
      "solar-arrays"
    ]
  },
  "properties": [
    {
      "benchmark": "band_gap",
      "label": "Band gap, In0.53Ga0.47As",
      "value": 0.75,
      "bound": "exact",
      "unit": "eV",
      "scope": "material",
      "conditions": {
        "composition": "In0.53Ga0.47As, lattice-matched to InP",
        "temperature": "295 K (table heading 'Value at 295 K')"
      },
      "method": "Value printed in the properties table of the Wikipedia article",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 4.1 (Properties table), row Band Gap; repeated in Section 4.3 (Bandgap energy)",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "lattice_constant",
      "label": "Lattice parameter, In0.53Ga0.47As",
      "value": 5.869,
      "bound": "exact",
      "unit": "Å",
      "scope": "material",
      "conditions": {
        "composition": "In0.53Ga0.47As, lattice-matched to InP",
        "temperature": "295 K (table heading 'Value at 295 K')"
      },
      "method": "Value printed in the properties table of the Wikipedia article",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 4.1 (Properties table), row Lattice Parameter",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "electron_mobility",
      "label": "Electron mobility, reasonably pure Ga0.47In0.53As",
      "value": 10000,
      "bound": "exact",
      "unit": "cm2/(V·s)",
      "scope": "material",
      "conditions": {
        "composition": "Ga0.47In0.53As",
        "temperature": "295 K",
        "purity": "reasonably pure, as the page says"
      },
      "method": "Printed 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.",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 4.1 (Properties table), row Electron mobility; Section 4.5 (Mobility of electrons and holes)",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "hole_mobility",
      "label": "Hole mobility, In0.53Ga0.47As",
      "value": 250,
      "bound": "exact",
      "unit": "cm2/(V·s)",
      "scope": "material",
      "conditions": {
        "composition": "In0.53Ga0.47As, lattice-matched to InP",
        "temperature": "295 K"
      },
      "method": "Printed as 250 cm2·V−1·s−1 in the properties table; unit written as cm2/(V·s)",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 4.1 (Properties table), row Hole mobility",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "electron_effective_mass",
      "label": "Electron effective mass, relative to free electron mass",
      "value": 0.041,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "composition": "In0.53Ga0.47As",
        "temperature": "295 K",
        "basis": "m*/m0, unitless as printed"
      },
      "method": "Value printed in the properties table (unitless)",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 4.1 (Properties table), row Electron effective mass; Section 4.4 (Effective mass)",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "cutoff_wavelength",
      "label": "Cut-off wavelength, In0.53Ga0.47As",
      "value": 1.68,
      "bound": "exact",
      "unit": "μm",
      "scope": "material",
      "conditions": {
        "composition": "In0.53Ga0.47As",
        "temperature": "295 K",
        "note": "the page gives the absorption edge as 0.75 eV for the same composition"
      },
      "method": "Value printed in the Materials synthesis section; the Wikipedia figure differs slightly from the NASA 2001 figure of 1.7 μm, and both are kept",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 2 (Materials synthesis), first table row",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Thermal expansion coefficient, GaInAs",
      "value": 5.66,
      "bound": "exact",
      "unit": "ppm/K",
      "scope": "material",
      "conditions": {
        "composition": "GaInAs (as the page names it)",
        "temperature": "not stated on the page",
        "unit_in_source": "5.66×10−6 K−1"
      },
      "method": "Printed 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.",
      "status": "ground",
      "source": "wiki-ingaas",
      "where": "Section 4.2 (FCC lattice parameter), first bullet",
      "source_detail": {
        "title": "Indium gallium arsenide (Wikipedia article)",
        "id": "Wikipedia, article text (no infobox captured)",
        "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
      }
    },
    {
      "benchmark": "reverse_saturation_current_density",
      "label": "Reverse saturation current density, InGaAs/InP photodiode",
      "value": 1e-8,
      "bound": "upper",
      "unit": "A/cm2",
      "scope": "cell",
      "conditions": {
        "composition": "In(.53)Ga(.47)As/InP",
        "temperature": "290 K",
        "device": "photodiode structure described in the abstract"
      },
      "method": "Upper bound printed in the abstract as 'JD < 10(exp -8) A/sq cm'",
      "status": "ground",
      "source": "ntrs-2001",
      "where": "Abstract",
      "source_detail": {
        "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging",
        "id": "NASA NTRS 20010072609; report AD-A390252; authors Cohen, Ettenberg, Lange, Olsen",
        "url": "https://ntrs.nasa.gov/citations/20010072609",
        "year": 2001,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "shunt_resistance_area_product",
      "label": "Shunt resistance-area product, InGaAs/InP photodiode",
      "value": 1000000,
      "bound": "lower",
      "unit": "ohm cm2",
      "scope": "cell",
      "conditions": {
        "composition": "In(.53)Ga(.47)As/InP",
        "temperature": "290 K"
      },
      "method": "Lower bound printed in the abstract as 'RoA > 10(exp 6) omega-sq cm'",
      "status": "ground",
      "source": "ntrs-2001",
      "where": "Abstract",
      "source_detail": {
        "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging",
        "id": "NASA NTRS 20010072609; report AD-A390252; authors Cohen, Ettenberg, Lange, Olsen",
        "url": "https://ntrs.nasa.gov/citations/20010072609",
        "year": 2001,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "detectivity",
      "label": "Detectivity (D*), InGaAs photodiode",
      "value": 100000000000000,
      "bound": "lower",
      "unit": "cm Hz^1/2 W^-1",
      "scope": "cell",
      "conditions": {
        "temperature": "290 K",
        "basis": "D* as printed in the abstract"
      },
      "method": "Lower bound printed in the abstract as 'greater than 10(exp 14) cm-(square root of Hz/W)'",
      "status": "ground",
      "source": "ntrs-2001",
      "where": "Abstract",
      "source_detail": {
        "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging",
        "id": "NASA NTRS 20010072609; report AD-A390252; authors Cohen, Ettenberg, Lange, Olsen",
        "url": "https://ntrs.nasa.gov/citations/20010072609",
        "year": 2001,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "spectral_range",
      "label": "Spectral sensitivity range, InGaAs focal-plane array",
      "value": 0.9,
      "value_high": 1.7,
      "bound": "range",
      "unit": "μm",
      "scope": "cell",
      "conditions": {
        "composition": "In(.53)Ga(.47)As/InP",
        "temperature": "not stated in the abstract",
        "note": "the short-wave cut-on is attributed in the abstract to absorption in the InP substrate"
      },
      "method": "Range printed in the abstract",
      "status": "ground",
      "source": "ntrs-2001",
      "where": "Abstract",
      "source_detail": {
        "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging",
        "id": "NASA NTRS 20010072609; report AD-A390252; authors Cohen, Ettenberg, Lange, Olsen",
        "url": "https://ntrs.nasa.gov/citations/20010072609",
        "year": 2001,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "quantum_efficiency",
      "label": "Quantum efficiency at 0.5 μm",
      "value": 15,
      "bound": "lower",
      "unit": "%",
      "scope": "cell",
      "conditions": {
        "wavelength": "0.5 μm",
        "composition": "InGaAs focal-plane array described in the abstract",
        "temperature": "not stated in the abstract"
      },
      "method": "Lower bound printed in the abstract as 'greater than 15% quantum efficiency at 0.5 micrometers'",
      "status": "ground",
      "source": "ntrs-2001",
      "where": "Abstract",
      "source_detail": {
        "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging",
        "id": "NASA NTRS 20010072609; report AD-A390252; authors Cohen, Ettenberg, Lange, Olsen",
        "url": "https://ntrs.nasa.gov/citations/20010072609",
        "year": 2001,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "bandwidth_3db",
      "label": "-3 dB bandwidth, InGaAs photodiode module flown on the ISS",
      "value": 16.8,
      "bound": "exact",
      "unit": "GHz",
      "scope": "cell",
      "conditions": {
        "device": "high-speed InGaAs photodiode module flown on the ISS (MISSE 7)",
        "measurement": "-3 dB bandwidth as printed in the abstract"
      },
      "method": "Value 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.",
      "status": "flight",
      "source": "ntrs-2017",
      "where": "Abstract",
      "source_detail": {
        "title": "Successful Space Flight of High-Speed InGaAs Photodiode Onboard the International Space Station",
        "id": "NASA NTRS 20170007487; NF1676L-27581; authors Joshi (Discovery Semiconductors), Prasad (NASA Langley), Datta (Discovery Semiconductors)",
        "url": "https://ntrs.nasa.gov/citations/20170007487",
        "year": 2017,
        "kind": "paper",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "temperature_cycling_range",
      "label": "Temperature cycling range in orbit, InGaAs photodiode module",
      "value": -157,
      "value_high": 121,
      "bound": "range",
      "unit": "degC",
      "scope": "cell",
      "conditions": {
        "device": "high-speed InGaAs photodiode module on the ISS",
        "cycling_frequency": "16 times a day"
      },
      "method": "Range printed in the 2017 conference abstract",
      "status": "flight",
      "source": "ntrs-2017",
      "where": "Abstract",
      "source_detail": {
        "title": "Successful Space Flight of High-Speed InGaAs Photodiode Onboard the International Space Station",
        "id": "NASA NTRS 20170007487; NF1676L-27581; authors Joshi (Discovery Semiconductors), Prasad (NASA Langley), Datta (Discovery Semiconductors)",
        "url": "https://ntrs.nasa.gov/citations/20170007487",
        "year": 2017,
        "kind": "paper",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "flight_duration",
      "label": "Time on the ISS, InGaAs photodiode module (MISSE 7)",
      "value": 18,
      "bound": "exact",
      "unit": "months",
      "scope": "cell",
      "conditions": {
        "launch": "16 November 2009",
        "return": "1 June 2011",
        "mission": "MISSE 7"
      },
      "method": "Duration printed in the 2017 conference abstract and in the 2012 article; the article gives launch and return dates",
      "status": "flight",
      "source": "ntrs-2017",
      "where": "Abstract; article body (laserfocusworld, 2012)",
      "source_detail": {
        "title": "Successful Space Flight of High-Speed InGaAs Photodiode Onboard the International Space Station",
        "id": "NASA NTRS 20170007487; NF1676L-27581; authors Joshi (Discovery Semiconductors), Prasad (NASA Langley), Datta (Discovery Semiconductors)",
        "url": "https://ntrs.nasa.gov/citations/20170007487",
        "year": 2017,
        "kind": "paper",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "bandwidth_3db",
      "label": "Bandwidth up to, DSC-R212 2.2 μm SWIR InGaAs receiver",
      "value": 18,
      "bound": "upper",
      "unit": "GHz",
      "scope": "cell",
      "conditions": {
        "product": "DSC-R212, 2.2 Micron SWIR InGaAs Linear AGC Balanced Optical Receiver",
        "wavelength": "2.2 μm"
      },
      "method": "Bandwidth printed in the product title on the manufacturer's featured-products list",
      "status": "ground",
      "source": "discovery-products",
      "where": "Featured Products: 2 Micron InGaAs Photodiodes & Photoreceivers, DSC-R212 entry",
      "source_detail": {
        "title": "Discovery Semiconductors, featured products: 2 Micron InGaAs Photodiodes and Photoreceivers",
        "id": "Discovery Semiconductors featured products page",
        "url": "https://www.discoverysemi.com/",
        "year": 2026,
        "kind": "datasheet",
        "license": "manufacturer web page, cited not reproduced"
      }
    },
    {
      "benchmark": "bandwidth_3db",
      "label": "Bandwidth up to, DSC2-100S 2.2 μm InGaAs photodiode",
      "value": 5,
      "bound": "upper",
      "unit": "GHz",
      "scope": "cell",
      "conditions": {
        "product": "DSC2-100S, 2.2 Micron Wavelength InGaAs Photodiode",
        "wavelength": "2.2 μm"
      },
      "method": "Bandwidth printed in the product title on the manufacturer's featured-products list (printed as 'up to 5 Ghz')",
      "status": "ground",
      "source": "discovery-products",
      "where": "Featured Products: 2 Micron InGaAs Photodiodes & Photoreceivers, DSC2-100S entry",
      "source_detail": {
        "title": "Discovery Semiconductors, featured products: 2 Micron InGaAs Photodiodes and Photoreceivers",
        "id": "Discovery Semiconductors featured products page",
        "url": "https://www.discoverysemi.com/",
        "year": 2026,
        "kind": "datasheet",
        "license": "manufacturer web page, cited not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Low Earth orbit on the ISS (MISSE 7 external exposure), with UV, radiation and thermal cycling",
      "headline": "The company says its InGaAs photodiodes looked intact after 18 months in orbit, but no numbers were published.",
      "effect": "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.",
      "rating": "low",
      "conditions": {
        "exposure": "18 months on the ISS, launched 16 November 2009, returned 1 June 2011",
        "basis": "qualitative statement by the company's CEO, no measured values; rating is assigned from that wording"
      },
      "source": "lfw-2012",
      "where": "Article body (CEO statement after the return of the modules)"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Wikipedia's safety section gives rodent exposure levels from National Toxicology Program studies of InP and GaAs (rats 0.01, 0.1 or 1.0 mg/m3; mice 0.1, 0.5 or 1.0 mg/m3). It does not print a GHS hazard class or a supplier safety data sheet for InGaAs itself, so no hazard statement is recorded here.",
        "ghs": [],
        "source": "wiki-ingaas",
        "where": "Section 6 (Safety and toxicity)"
      }
    ],
    "failure_risks": [],
    "side_effects": [],
    "handling": [],
    "mitigations": []
  },
  "uses": [
    {
      "application": "optics-and-cameras",
      "device": "Short-wave infrared focal-plane array for low light level imaging",
      "example": "NASA's 2001 report describes an In(.53)Ga(.47)As/InP visible/SWIR focal-plane array sensitive from 0.9 μm to 1.7 μm for low light level imaging.",
      "source": "ntrs-2001",
      "where": "Abstract"
    },
    {
      "application": "optics-and-cameras",
      "device": "High-speed photodiode module on the ISS (MISSE 7)",
      "example": "A high-speed InGaAs photodiode module completed 18 months on the ISS, launched 16 November 2009 and returned 1 June 2011, per the 2017 conference paper.",
      "source": "ntrs-2017",
      "where": "Abstract"
    },
    {
      "application": "optics-and-cameras",
      "device": "Fibre-optic telecommunications photodetector",
      "example": "Wikipedia describes InGaAs photodiodes as the principal use of the alloy, as fast and sensitive detectors for fibre-optic telecommunications.",
      "source": "wiki-ingaas",
      "where": "Main applications list (Photodetectors) in the article text"
    },
    {
      "application": "solar-arrays",
      "device": "Triple-junction solar cells and thermophotovoltaic power generation",
      "example": "Wikipedia lists triple-junction solar cells and thermophotovoltaic power generation among the photovoltaic uses of InGaAs.",
      "source": "wiki-ingaas",
      "where": "Main applications list (Photovoltaics) in the article text"
    },
    {
      "application": "electronics-and-chips",
      "device": "High-electron-mobility transistors (HEMTs) with InGaAs channels",
      "example": "Wikipedia lists HEMTs with InGaAs channels among the transistor uses of the alloy.",
      "source": "wiki-ingaas",
      "where": "Main applications list (Transistors) in the article text"
    }
  ],
  "supply": [
    {
      "subject": "Indium",
      "producers": [
        {
          "country": "China",
          "share_percent": 70,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals (indium listed for flat-panel displays and touchscreens)",
          "listed": true
        },
        {
          "list": "EU critical raw materials list (Regulation (EU) 2024/1252, as shown on the European Commission page)",
          "listed": false
        }
      ],
      "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)."
      ],
      "source": "usgs-indium",
      "where": "Events, Trends and Issues (China accounted for 70% of the world total); World Refinery Production table, 2025e; Recycling; Substitutes"
    },
    {
      "subject": "Gallium",
      "producers": [
        {
          "country": "China",
          "share_percent": 99,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals (gallium listed for semiconductors)",
          "listed": true
        },
        {
          "list": "EU critical raw materials list (Regulation (EU) 2024/1252, as shown on the European Commission page)",
          "listed": true
        }
      ],
      "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.",
      "substitutes": [],
      "source": "usgs-gallium",
      "where": "Events, Trends and Issues (China accounted for 99% of worldwide primary low-purity gallium production; the text does not date this share more finely than the 2026 chapter); Recycling"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Wikipedia: Indium gallium arsenide (article text, fetched 2026-11-01)",
      "type": "database",
      "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
      "year": 2026
    },
    {
      "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging (NASA NTRS 20010072609)",
      "type": "report",
      "url": "https://ntrs.nasa.gov/citations/20010072609",
      "year": 2001
    },
    {
      "title": "Successful Space Flight of High-Speed InGaAs Photodiode Onboard the International Space Station (NASA NTRS 20170007487)",
      "type": "paper",
      "url": "https://ntrs.nasa.gov/citations/20170007487",
      "year": 2017
    },
    {
      "title": "Discovery Semiconductors InGaAs photodiode modules return to Earth after 18 months on the ISS (Laser Focus World, 23 May 2012)",
      "type": "report",
      "url": "https://www.laserfocusworld.com/test-measurement/research/article/16565684/discovery-semiconductors-ingaas-photodiode-modules-return-to-earth-after-18-months-on-the-iss",
      "year": 2012
    },
    {
      "title": "Discovery Semiconductors featured products, 2 Micron InGaAs photodiodes and photoreceivers",
      "type": "datasheet",
      "url": "https://www.discoverysemi.com/",
      "year": 2026
    },
    {
      "title": "Mineral Commodity Summaries 2026, Indium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-indium.pdf",
      "year": 2026
    },
    {
      "title": "Mineral Commodity Summaries 2026, Gallium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-gallium.pdf",
      "year": 2026
    }
  ],
  "gaps": [
    "Pre-flight versus post-flight performance is not stated in any source read. The brief's 'no performance change' claim for the ISS module is not confirmed: the 2017 abstract prints only the 16.8 GHz bandwidth, and the 2012 article gives no numbers and says post-flight tests had only just started.",
    "Atomic weights of indium, gallium and arsenic were not read in this run, so they are not entered in story.recipe.",
    "No CAS number, EC number, space group, crystal system, UNS, EN or other designation for InGaAs appears in any source read; none entered.",
    "Density, melting point, thermal conductivity, refractive index and dielectric constant are not printed on the Wikipedia page, and no other source read gives them. Not found in any source we hold.",
    "Band gap, lattice constant, electron and hole mobility, electron effective mass, cut-off wavelength, detector figures and ISS duration are not canonical names in spores/property-canon.yaml. They are entered under snake_case names (band_gap, lattice_constant, electron_mobility, hole_mobility, electron_effective_mass, cutoff_wavelength, reverse_saturation_current_density, shunt_resistance_area_product, detectivity, spectral_range, quantum_efficiency, bandwidth_3db, temperature_cycling_range, flight_duration).",
    "Two cut-off wavelengths for the same alloy: 1.68 μm in the Wikipedia Materials synthesis section (at 295 K) and 1.7 μm long-wavelength cut-off in the 2001 NASA abstract (at 290 K, for the focal-plane array). Both are kept as printed.",
    "Section 4.5 of the Wikipedia page prints 250 cm2/s as a room-temperature electron diffusion constant. The same number is the hole mobility in its table, so the diffusion value is not entered.",
    "Corrosion and ageing: no measured degradation data for InGaAs in vacuum, UV, radiation or thermal cycling were found. The only exposure statement is qualitative (company CEO, 2012 article).",
    "Failure modes, handling and mitigations: no sourced entries. No GHS classification or supplier safety data sheet for InGaAs was read; Wikipedia gives rodent exposure levels, not a hazard class.",
    "Supply: no production or refinery data for arsenic were read, so arsenic is not entered in supply. Arsenic is on the USGS 2025 and EU critical lists (confirmed on the USGS and European Commission pages), with no producer shares.",
    "Radiation dose, vacuum and thermal-vacuum results beyond the one ISS flight were not found in any source read. No second flight or ground-test source with numbers was found."
  ],
  "story": {
    "why": "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.",
    "uses": [
      {
        "where": "Fibre-optic telecommunications",
        "line": "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."
      },
      {
        "where": "Imaging in low light",
        "line": "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."
      },
      {
        "where": "On the International Space Station",
        "line": "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."
      }
    ],
    "can_do": [
      {
        "label": "Band gap",
        "line": "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.",
        "benchmark": "band_gap",
        "scope": "material"
      },
      {
        "label": "Response range",
        "line": "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.",
        "benchmark": "spectral_range",
        "scope": "material"
      },
      {
        "label": "Bandwidth",
        "line": "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.",
        "benchmark": "bandwidth_3db",
        "scope": "material"
      },
      {
        "label": "Electron transport",
        "line": "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.",
        "benchmark": "electron_mobility",
        "scope": "material"
      }
    ],
    "compare": "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.",
    "compare_rows": [
      {
        "label": "Band gap",
        "benchmark": "band_gap",
        "scope": "material"
      },
      {
        "label": "Electron mobility",
        "benchmark": "electron_mobility",
        "scope": "material"
      },
      {
        "label": "Short-wave cut-off",
        "benchmark": "cutoff_wavelength",
        "scope": "material"
      }
    ],
    "handling": [
      "No handling or storage guidance for InGaAs was found in the sources read. Follow the supplier's safety data sheet for any wafer or module you handle.",
      "Wikipedia's exposure levels are study values for rodents, not safe limits for people."
    ],
    "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": [
      "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."
    ],
    "verdict": "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.",
    "recipe": {
      "line": "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).",
      "parts": [
        {
          "name": "Indium",
          "symbol": "In",
          "role": "Group III element; the 0.53 share is the indium fraction in the lattice-matched composition the page uses."
        },
        {
          "name": "Gallium",
          "symbol": "Ga",
          "role": "Group III element; the 0.47 share is the gallium fraction in the same composition."
        },
        {
          "name": "Arsenic",
          "symbol": "As",
          "role": "Group V element; the alloy notation GaxIn1-xAs has one arsenic atom per formula unit."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "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.",
        "points": [
          {
            "label": "Exposure studies",
            "line": "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."
          },
          {
            "label": "Dust",
            "line": "No dust or inhalation hazard statement for InGaAs was found in the sources read."
          }
        ],
        "level": 0,
        "verdict": "No GHS hazard class found for InGaAs"
      },
      {
        "title": "In orbit",
        "lead": "The only flight result found is one 18-month exposure of a photodiode module on the ISS.",
        "points": [
          {
            "label": "Flight",
            "line": "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)."
          },
          {
            "label": "Thermal cycling",
            "line": "The module was cycled between -157 and +121 degC, 16 times a day, according to the 2017 conference abstract."
          },
          {
            "label": "Result",
            "line": "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."
          }
        ]
      }
    ]
  },
  "updated": "2026-11-01",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 17,
    "unreachable": 0,
    "caveats": 2,
    "note": "Written by an AI assistant on 2026-11-01 from pages fetched in this run. The web search budget for this turn was used up, so the source set is smaller than the brief's target. Not re-read by a second check."
  },
  "sources": {
    "wiki-ingaas": {
      "title": "Indium gallium arsenide (Wikipedia article)",
      "id": "Wikipedia, article text (no infobox captured)",
      "url": "https://en.wikipedia.org/wiki/Indium_gallium_arsenide",
      "year": 2026,
      "kind": "web",
      "license": "CC BY-SA 4.0 (Wikipedia; cited, not reproduced)"
    },
    "ntrs-2001": {
      "title": "An Indium Gallium Arsenide Visible/SWIR Focal Plane Array for Low Light Level Imaging",
      "id": "NASA NTRS 20010072609; report AD-A390252; authors Cohen, Ettenberg, Lange, Olsen",
      "url": "https://ntrs.nasa.gov/citations/20010072609",
      "year": 2001,
      "kind": "report",
      "license": "public domain (NASA)"
    },
    "ntrs-2017": {
      "title": "Successful Space Flight of High-Speed InGaAs Photodiode Onboard the International Space Station",
      "id": "NASA NTRS 20170007487; NF1676L-27581; authors Joshi (Discovery Semiconductors), Prasad (NASA Langley), Datta (Discovery Semiconductors)",
      "url": "https://ntrs.nasa.gov/citations/20170007487",
      "year": 2017,
      "kind": "paper",
      "license": "public domain (NASA)"
    },
    "lfw-2012": {
      "title": "Discovery Semiconductors InGaAs photodiode modules return to Earth after 18 months on the ISS",
      "id": "Laser Focus World, 23 May 2012",
      "url": "https://www.laserfocusworld.com/test-measurement/research/article/16565684/discovery-semiconductors-ingaas-photodiode-modules-return-to-earth-after-18-months-on-the-iss",
      "year": 2012,
      "kind": "web",
      "license": "publisher article, cited not reproduced"
    },
    "discovery-products": {
      "title": "Discovery Semiconductors, featured products: 2 Micron InGaAs Photodiodes and Photoreceivers",
      "id": "Discovery Semiconductors featured products page",
      "url": "https://www.discoverysemi.com/",
      "year": 2026,
      "kind": "datasheet",
      "license": "manufacturer web page, cited not reproduced"
    },
    "usgs-indium": {
      "title": "Mineral Commodity Summaries 2026, Indium",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-indium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-gallium": {
      "title": "Mineral Commodity Summaries 2026, Gallium",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-gallium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-crit2025": {
      "title": "About the 2025 List of Critical Minerals (USGS, 60 minerals)",
      "id": "USGS, final 2025 List of Critical Minerals",
      "url": "https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals",
      "year": 2025,
      "kind": "web",
      "license": "public domain (USGS)"
    },
    "ec-crm": {
      "title": "Critical raw materials (European Commission, list under Regulation (EU) 2024/1252)",
      "id": "Regulation (EU) 2024/1252",
      "url": "https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en",
      "year": 2024,
      "kind": "web",
      "license": "European Commission web page"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/indium-gallium-arsenide/"
}