Indium phosphide InP
InP, one indium atom and one phosphorus atom in a zinc-blende crystal · CAS 22398-80-7 · cubic
Indium phosphide (InP) is a binary III-V semiconductor of one indium atom and one phosphorus atom, sold by Shalomeo as single-crystal substrates.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Electron speed
5400 cm2/(V·s) at 300 K
Band gap
1.344 eV at 300 K
Lattice match
5.869 Å
Heat conduction
0.68 W/(cm·K)
Recipe, share of the weight
- In not statedIndium
- P not statedPhosphorus
Best for
Substrates for InGaAs photodiodes and detectors, and for high-speed electronics and telecom devices, where a band gap of 1.344 eV and an electron mobility of 5400 cm2/(V·s) at 300 K are the reasons to choose it
Weakest at
Supply and toxicity: the United States imports all of its indium, China produced 70% of world indium (USGS), and PubChem's ECHA summary gives H350 (May cause cancer) for 98.1% of reports that list codes
Risk at a glance
- People Moderate. Cancer classification in most reports
- If it fails No data. No failure risks recorded
- Corrosion Low. The supplier calls indium phosphide slightly soluble in acids; no acid, temperature or exposure time is given.
Quick facts: InP
| Property | Value | Basis |
|---|---|---|
| Density | 4.81 g/cm³ | 1 sourced value |
| Thermal conductivity | 68 W/(m·K) | 1 sourced value |
| Melting point | 1,062 to 1,330 °C | 2 sourced values across conditions |
| Electrical resistivity | 0.0003 to 0.002 Ω·m | 1 sourced value |
What is the density of Indium phosphide (InP)?
Indium phosphide (InP) has a density of 4.81 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Indium phosphide (InP)?
Indium phosphide (InP) has a thermal conductivity of 68 W/(m·K). The source and test conditions are listed in the properties table on this page.
What is the melting point of Indium phosphide (InP)?
Indium phosphide (InP) has a melting point of 1,062 to 1,330 °C. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is Indium phosphide (InP) used for?
Uses recorded in the sources include InGaAs photodiodes and detectors grown on InP substrates; High-frequency transistors built on InP and InGaAs; Telecom lasers, photodetectors and receivers.
Why it exists
Indium phosphide (InP) is a III-V semiconductor, made of indium and phosphorus in a 1:1 ratio, that is sold as a single-crystal substrate. Shalomeo lists its features as high electron mobility, good radiation stability and a large band gap, and gives a band gap of 1.344 eV at 300 K and an electron mobility of 5400 cm2/(V·s) at 300 K. Its main role is as the substrate for indium gallium arsenide, because the In0.53Ga0.47As alloy matches the InP lattice (Wikipedia).
Where it's used
Photodiodes and detectors
Most InGaAs devices are grown on InP substrates. For 1.1 μm to 1.7 μm, GaInAs photodiodes are the preferred choice, and the 53% indium composition has a cut-off of 1.68 μm at 295 K (Wikipedia).
High-frequency transistors
Shalomeo says InP performs superiorly in high-power and high-frequency electronics. Wikipedia reports pseudomorphic heterojunction bipolar transistors that could operate at 604 GHz.
Telecom lasers and receivers
USGS reports that InP lasers and receivers send data through fiber-optic lines in 5G networks, and that InP is used in high-speed photodetectors and laser diodes for optical communications.
Recipe
InP, one indium atom and one phosphorus atom in a zinc-blende crystal
Indium phosphide is a binary compound of one indium atom and one phosphorus atom, with the formula InP (PubChem). It crystallises in the zinc-blende structure (Wikipedia). Wikipedia lists three routes: reacting white phosphorus with indium iodide at high temperature, direct combination of purified indium and phosphorus at high temperature and pressure, and thermal decomposition of a trialkyl indium compound mixed with phosphine.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Indium In | not stated | The group III element. Indium gallium arsenide replaces part of this indium with gallium so that the alloy matches the InP lattice. |
| Phosphorus P | not stated | The group V element. One phosphorus atom per formula unit, in the tetrahedral coordination that the supplier table prints. |
Weight shares are as printed in the sources.
What it can do
Electron speed
5400 cm2/(V·s) at 300 K
measured
Electron mobility is 5400 cm2/(V·s) at 300 K (Shalomeo). Surfacenet gives 3700 to 4000 cm2/ V-S for undoped N-type (100) crystal, so the exact figure depends on the material and its conditions.
Band gap
1.344 eV at 300 K
measured
The band gap is 1.344 eV at 300 K (Shalomeo). The Wikipedia infobox describes this gap as direct.
Lattice match
5.869 Å
measured
The lattice constant is 5.869 Å (Shalomeo). Wikipedia gives 5.869 Å at 295 K for the In0.53Ga0.47As alloy, which matches InP at that temperature.
Heat conduction
0.68 W/(cm·K)
measured
Thermal conductivity is 0.68 W/(cm·K) at 300 K (Shalomeo).
How it compares
Indium phosphide sits with the other III-V compound semiconductors in this collection. Compared with gallium arsenide, the figures we hold put InP at a smaller band gap and a lower electron mobility at 300 K. InP's main role is as the substrate on which InGaAs devices are grown. The table compares InP with the other semiconductors in this collection on density, band gap and electron mobility.
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.
| Measurement | InP |
|---|---|
| Thermal behavior and safety | |
| Melting point, InP (Shalomeo) | 1062 °C2 |
| Melting point, InP (Surfacenet, (100) block) | 1330 °C3 |
| Thermal conductivity of InP at 300 K | 0.68 W/(cm·K)8 |
| Physical and electrical | |
| Density of InP single crystal | 4.81 g/cm³1 |
| Electrical resistivity, (100) InP | 0.03 to 0.2 Ohm cm13 |
| Other measurements | |
| Band gap of InP at 300 K | 1.344 eV4 |
| Electron mobility of InP at 300 K | 5400 cm²/(V·s)5 |
| Mobility, undoped N-type InP, (100) crystal | 3700 to 4000 cm²/ V-S6 |
| Mobility, undoped N-type InP, (111) crystal (upper bound) | < 3000 cm²/ V-S7 |
| Refractive index of InP at 632.8 nm | 3.55 -9 |
| Lattice constant of InP (Shalomeo) | 5.869 Å10 |
| Lattice constant of InP (Surfacenet, (100) block) | 5.868 Å11 |
| Molar mass of InP | 145.8 g/mol12 |
Why choose it, and why not
Good for
- Substrates for InGaAs detectors and photodiodes, where the InP lattice matches In0.53Ga0.47As at 295 K.
- High-frequency transistors. Wikipedia reports pseudomorphic transistors that could operate at 604 GHz.
- Telecom lasers and receivers, which USGS says carry fiber-optic traffic in 5G networks.
Watch out for
- Cancer classification: PubChem's ECHA summary gives H350 for 98.1% of reports that list codes.
- Supply: China produced 70% of world indium (USGS), China added indium to new export restrictions in February 2025, and the United States imports all of its indium.
- Melting point: 1062 °C from Shalomeo and Wikipedia, but 1330 °C from Surfacenet.
- No space flight or radiation-dose data for InP were found, so the space case rests on supplier statements.
InP is the lattice-matched substrate for InGaAs detectors and a fast-electron material for high-frequency and telecom devices. The supplier and database pages agree on density, band gap and lattice constant, but they disagree on the melting point, and the mobility figures need their conditions. The cancer classification and dependence on Chinese indium supply are the points to watch. This profile has no space flight data.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density of InP single crystal | Value printed in a substrate supplier's basic properties table | form InP single crystal (substrate product)temperature not stated on the page | — |
| 2 | Melting point, InP (Shalomeo) | Value printed in a substrate supplier's basic properties table | form InP single crystalpressure not stated on the page | Wikipedia's infobox also prints 1,062 °C. Surfacenet prints 1330 °C for the same material (next entry). The two values disagree and both are kept. |
| 3 | Melting point, InP (Surfacenet, (100) block) | Value printed on a materials data page under the crystal properties block for the (100) orientation | orientation (100)page note degree sign is garbled on the page | Disagrees with the 1062 °C from Shalomeo and Wikipedia. The disagreement is not resolved here. |
| 4 | Band gap of InP at 300 K | Value printed in a substrate supplier's basic properties table | temperature 300 K | The Wikipedia infobox describes this gap as direct; the supplier table does not print the gap type. |
| 5 | Electron mobility of InP at 300 K | Value printed in a substrate supplier's basic properties table | temperature 300 K | Surfacenet gives different figures for undoped N-type (100) and (111) crystal (next two entries). The conditions differ and the values are not reconciled. |
| 6 | Mobility, undoped N-type InP, (100) crystal | Range printed on a materials data page under the crystal properties block; the page gives it as mobility for N-type material without naming a temperature | orientation (100)doping undoped, N-typetemperature not stated on the page | — |
| 7 | Mobility, undoped N-type InP, (111) crystal (upper bound) | Upper bound printed on a materials data page (the page prints "< 3000") | orientation (111)doping undoped, N-typetemperature not stated on the page | — |
| 8 | Thermal conductivity of InP at 300 K | Value printed in a substrate supplier's basic properties table | temperature 300 K | — |
| 9 | Refractive index of InP at 632.8 nm | Value printed in a substrate supplier's basic properties table | wavelength 632.8nm | — |
| 10 | Lattice constant of InP (Shalomeo) | Value printed in a substrate supplier's basic properties table | structure zinc blende (cubic)temperature not stated on the page | Surfacenet prints 5.868 Å, and the Wikipedia InGaAs article gives 5.869 Å at 295 K for the In0.53Ga0.47As alloy that matches InP. The values agree within rounding. |
| 11 | Lattice constant of InP (Surfacenet, (100) block) | Value printed on a materials data page under the crystal properties block | orientation (100) blockstructure cubicunit as printed A | — |
| 12 | Molar mass of InP | Value printed in a substrate supplier's basic properties table; PubChem prints the same molecular weight (145.792) without a unit | basis molecular weight of the InP formula unit | — |
| 13 | Electrical resistivity, (100) InP | Range printed on a materials data page under the crystal properties block | orientation (100)doping not stated on the row | The page does not tie this resistivity to a doping type, so it is kept apart from the mobility rows. |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Acids | low | The supplier calls indium phosphide slightly soluble in acids; no acid, temperature or exposure time is given.1 |
| Ionising radiation | low | The supplier claims good radiation stability, with no dose or fluence figure.2 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Acids | Shalomeo lists chemical stability as slightly soluble in acids. The statement is qualitative: the page names no acid, concentration, temperature or time, so no corrosion rate can be stated. | basis qualitative chemical-stability statement from a supplieracid not named on the page |
| 2 | Ionising radiation | Shalomeo lists good radiation stability among the features of its InP substrates and names radiation-resistant solar cells as an application. The page prints no dose, fluence or test result for the claim. | basis supplier feature statement with no test givendose not stated on the page |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
PubChem's ECHA summary classifies indium phosphide as a cancer hazard in most reports that give codes. The classification varies between notifications, and no supplier safety data sheet was opened.
- Classification
- PubChem's ECHA summary covers 211 company reports from 8 notifications. Of the reports that give codes, 98.1% list H350 (May cause cancer), 94.3% list H361 (Suspected of damaging fertility or the unborn child) and 98.1% list H372 (Causes damage to organs through prolonged or repeated exposure). The signal word is Danger.
- Other notifications
- One notification reads Not Classified. Others list H350 and H372 with the signal word Danger.
- Wafer packing
- Shalomeo packs its substrates in class 100 bags inside a class 1000 clean room. That is the only supplier handling statement that was read.
In service
No space failure data for InP were found. The radiation statements that were read carry no numbers.
- Radiation
- Shalomeo says InP has good radiation stability, but it gives no dose, fluence or test result for that claim.
- Surface
- Shalomeo gives a surface roughness of Ra ≤5 Å for polished substrates, printed as Ra:≤5A.
Handling and storage
- Packaging
- Shalomeo ships the substrates in class 100 bags inside a class 1000 clean room. Keep them in those bags until use.
Test details
The original wording and numbers from the sources, for readers who want them.
Handling and storage
- Shalomeo packages its InP substrates in class 100 bags inside a class 1000 clean room.
- No supplier safety data sheet for InP was opened. Get the supplier's sheet before cutting, etching or grinding the material, because the only hazard data here come from the PubChem classification.
Supply and geography
How common the raw materials are and where they come from.
Indium (the metal used to make InP)
- Top producers (2025)
- China 69.1%, Korea, Republic of 16.4%, Japan 5.9%, Canada 3.6%
- 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; the quantity recovered from scrap is not available.
- Substitutes
- USGS: the substitutes it names are for indium tin oxide coatings (antimony tin oxide, carbon nanotubes, PEDOT, copper or silver nanowires, graphene), not for InP wafers.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: indium-phosphide
spore_version: 0.2
family: semiconductor-materials
name: Indium phosphide
abbreviation: InP
role: semiconductor
category: semiconductors
type: inp
summary: |
Indium phosphide (InP) is a binary III-V semiconductor of one indium atom and one phosphorus atom, sold by Shalomeo as single-crystal substrates. Shalomeo gives a density of 4.81 g/cm3, a band gap of 1.344 eV at 300 K and an electron mobility of 5400 cm2/(V·s) at 300 K. Most InGaAs devices are grown on InP, because In0.53Ga0.47As matches its lattice (Wikipedia). PubChem's ECHA summary classifies InP as a cancer hazard (H350) in most of the reports that give hazard codes.
best_for: Substrates for InGaAs photodiodes and detectors, and for high-speed electronics and telecom devices, where a band gap of 1.344 eV and an electron mobility of 5400 cm2/(V·s) at 300 K are the reasons to choose it
weakest_at: 'Supply and toxicity: the United States imports all of its indium, China produced 70% of world indium (USGS), and PubChem''s ECHA summary gives H350 (May cause cancer) for 98.1% of reports that list codes'
identity:
formula: InP, one indium atom and one phosphorus atom in a zinc-blende crystal
cas: 22398-80-7
crystal_system: cubic
source: shalomeo-inp
where: Basic Properties table of the Shalomeo page (crystal structure Tetrahedral(M4), lattice constant a = 5.869 Å); cubic from the Surfacenet crystal properties; zinc blende and CAS 22398-80-7 from the Wikipedia infobox
tags:
environments: []
stresses: []
applications:
- electronics-and-chips
- optics-and-cameras
- solar-arrays
properties:
- benchmark: density
label: Density of InP single crystal
value: 4.81
unit: g/cm3
scope: material
conditions:
form: InP single crystal (substrate product)
temperature: not stated on the page
method: Value printed in a substrate supplier's basic properties table
status: ground
source: shalomeo-inp
where: Basic Properties table, row Density
- benchmark: melting_point
label: Melting point, InP (Shalomeo)
value: 1062
unit: °C
scope: material
conditions:
form: InP single crystal
pressure: not stated on the page
method: Value printed in a substrate supplier's basic properties table
status: ground
note: Wikipedia's infobox also prints 1,062 °C. Surfacenet prints 1330 °C for the same material (next entry). The two values disagree and both are kept.
source: shalomeo-inp
where: Basic Properties table, row Melt Point
- benchmark: melting_point
label: Melting point, InP (Surfacenet, (100) block)
value: 1330
unit: °C
scope: material
conditions:
orientation: (100)
page_note: degree sign is garbled on the page
method: Value printed on a materials data page under the crystal properties block for the (100) orientation
status: ground
note: Disagrees with the 1062 °C from Shalomeo and Wikipedia. The disagreement is not resolved here.
source: surfacenet-inp
where: Crystal properties, (100) block, melting point row
- benchmark: band_gap
label: Band gap of InP at 300 K
value: 1.344
unit: eV
scope: material
conditions:
temperature: 300 K
method: Value printed in a substrate supplier's basic properties table
status: ground
note: The Wikipedia infobox describes this gap as direct; the supplier table does not print the gap type.
source: shalomeo-inp
where: Basic Properties table, row Bandgap (@300 K)
- benchmark: electron_mobility
label: Electron mobility of InP at 300 K
value: 5400
unit: cm2/(V·s)
scope: material
conditions:
temperature: 300 K
method: Value printed in a substrate supplier's basic properties table
status: ground
note: Surfacenet gives different figures for undoped N-type (100) and (111) crystal (next two entries). The conditions differ and the values are not reconciled.
source: shalomeo-inp
where: Basic Properties table, row Electron Mobility (@300K)
- benchmark: electron_mobility
label: Mobility, undoped N-type InP, (100) crystal
value: 3700
value_high: 4000
bound: range
unit: cm2/ V-S
scope: material
conditions:
orientation: (100)
doping: undoped, N-type
temperature: not stated on the page
method: Range printed on a materials data page under the crystal properties block; the page gives it as mobility for N-type material without naming a temperature
status: ground
source: surfacenet-inp
where: Crystal properties, (100) block, mobility row
- benchmark: electron_mobility
label: Mobility, undoped N-type InP, (111) crystal (upper bound)
value: 3000
bound: upper
unit: cm2/ V-S
scope: material
conditions:
orientation: (111)
doping: undoped, N-type
temperature: not stated on the page
method: Upper bound printed on a materials data page (the page prints "< 3000")
status: ground
source: surfacenet-inp
where: Crystal properties, (111) block, mobility row
- benchmark: thermal_conductivity
label: Thermal conductivity of InP at 300 K
value: 0.68
unit: W/(cm·K)
scope: material
conditions:
temperature: 300 K
method: Value printed in a substrate supplier's basic properties table
status: ground
source: shalomeo-inp
where: Basic Properties table, row Thermal Conductivity (@300K)
- benchmark: refractive_index
label: Refractive index of InP at 632.8 nm
value: 3.55
unit: '-'
scope: material
conditions:
wavelength: 632.8nm
method: Value printed in a substrate supplier's basic properties table
status: ground
source: shalomeo-inp
where: Basic Properties table, row Refractive Index
- benchmark: lattice_constant
label: Lattice constant of InP (Shalomeo)
value: 5.869
unit: Å
scope: material
conditions:
structure: zinc blende (cubic)
temperature: not stated on the page
method: Value printed in a substrate supplier's basic properties table
status: ground
note: Surfacenet prints 5.868 Å, and the Wikipedia InGaAs article gives 5.869 Å at 295 K for the In0.53Ga0.47As alloy that matches InP. The values agree within rounding.
source: shalomeo-inp
where: Basic Properties table, row Lattice Constant
- benchmark: lattice_constant
label: Lattice constant of InP (Surfacenet, (100) block)
value: 5.868
unit: Å
scope: material
conditions:
orientation: (100) block
structure: cubic
unit_as_printed: A
method: Value printed on a materials data page under the crystal properties block
status: ground
source: surfacenet-inp
where: Crystal properties, (100) block, crystal structure and lattice constant row
- benchmark: molar_mass
label: Molar mass of InP
value: 145.792
unit: g/mol
scope: material
conditions:
basis: molecular weight of the InP formula unit
method: Value printed in a substrate supplier's basic properties table; PubChem prints the same molecular weight (145.792) without a unit
status: ground
source: shalomeo-inp
where: Basic Properties table, row Molar Mass
- benchmark: electrical_resistivity
label: Electrical resistivity, (100) InP
value: 0.03
value_high: 0.2
bound: range
unit: Ohm cm
scope: material
conditions:
orientation: (100)
doping: not stated on the row
method: Range printed on a materials data page under the crystal properties block
status: ground
note: The page does not tie this resistivity to a doping type, so it is kept apart from the mobility rows.
source: surfacenet-inp
where: Crystal properties, (100) block, resistivity row
corrosion:
- environment: Acids
headline: The supplier calls indium phosphide slightly soluble in acids; no acid, temperature or exposure time is given.
effect: 'Shalomeo lists chemical stability as slightly soluble in acids. The statement is qualitative: the page names no acid, concentration, temperature or time, so no corrosion rate can be stated.'
rating: low
conditions:
basis: qualitative chemical-stability statement from a supplier
acid: not named on the page
source: shalomeo-inp
where: Basic Properties table, row Chemical Stability
- environment: Ionising radiation
headline: The supplier claims good radiation stability, with no dose or fluence figure.
effect: Shalomeo lists good radiation stability among the features of its InP substrates and names radiation-resistant solar cells as an application. The page prints no dose, fluence or test result for the claim.
rating: low
conditions:
basis: supplier feature statement with no test given
dose: not stated on the page
source: shalomeo-inp
where: Features statement and application fields
risks:
hazards:
- text: PubChem's ECHA summary for indium phosphide (211 company reports from 8 notifications) gives H350 (May cause cancer) for 98.1% of reports that give codes, H361 (Suspected of damaging fertility or the unborn child) for 94.3%, and H372 (Causes damage to organs through prolonged or repeated exposure) for 98.1%. The signal word is Danger.
ghs:
- H350
- H361
- H372
source: pubchem-inp
where: Safety and Hazards, GHS Classification, ECHA C&L Notifications Summary (CID 31170)
- text: Individual notifications differ. One reads Not Classified, and others list H350 and H372 with the signal word Danger. PubChem notes that the classification varies with impurities, additives and other factors.
ghs: []
source: pubchem-inp
where: Safety and Hazards, GHS Classification, individual notifications
failure_risks: []
side_effects: []
handling:
- text: Shalomeo packages its InP substrates in class 100 bags inside a class 1000 clean room.
source: shalomeo-inp
where: Packaging statement in the product specifications
- text: No supplier safety data sheet for InP was opened. Get the supplier's sheet before cutting, etching or grinding the material, because the only hazard data here come from the PubChem classification.
source: pubchem-inp
where: Safety and Hazards, GHS Classification
mitigations: []
uses:
- application: optics-and-cameras
device: InGaAs photodiodes and detectors grown on InP substrates
example: Most InGaAs devices are grown on InP substrates. The In0.53Ga0.47As alloy matches the InP lattice at 295 K, GaInAs photodiodes are the preferred choice from 1.1 μm to 1.7 μm, and the 53% indium composition has a cut-off of 1.68 μm at 295 K.
source: wikipedia-ingaas
where: Introduction; lattice-matching section; photodiode section
- application: electronics-and-chips
device: High-frequency transistors built on InP and InGaAs
example: Shalomeo says InP performs superiorly in high-power and high-frequency electronics. Wikipedia reports pseudomorphic heterojunction bipolar transistors that could operate at 604 GHz.
source: wikipedia-inp
where: Uses section, RF and high-speed electronics paragraph; Shalomeo application statements
- application: optics-and-cameras
device: Telecom lasers, photodetectors and receivers
example: USGS reports that InP lasers and receivers send data through fiber-optic lines in 5G networks, and that InP is used in high-speed photodetectors and laser diodes for optical communications.
source: usgs-mcs2026-indium
where: Events, Trends, and Issues
- application: solar-arrays
device: Radiation-resistant solar cells
example: Shalomeo lists radiation-resistant solar cells among the application fields of its InP substrates. The page prints no cell efficiency and no radiation dose.
source: shalomeo-inp
where: Product and application statements
supply:
- subject: Indium (the metal used to make InP)
producers:
- country: China
share_percent: 69.1
year: 2025
- country: Korea, Republic of
share_percent: 16.4
year: 2025
- country: Japan
share_percent: 5.9
year: 2025
- country: Canada
share_percent: 3.6
year: 2025
critical_lists:
- list: USGS 2025 List of Critical Minerals (final list, November 2025)
listed: true
- list: EU critical raw materials list (European Commission page)
listed: false
recycling: 'USGS: indium is most commonly recovered from ITO scrap in Japan and the Republic of Korea; the quantity recovered from scrap is not available.'
substitutes:
- 'USGS: the substitutes it names are for indium tin oxide coatings (antimony tin oxide, carbon nanotubes, PEDOT, copper or silver nanowires, graphene), not for InP wafers.'
source: usgs-mcs2026-indium
where: World Refinery Production and Capacity table, 2025e (world total 1,100 metric tons; shares calculated by Space Mushroom from China 760, Korea 180, Japan 65 and Canada 40 tons); Events, Trends, and Issues (China 70% of the world total, as printed); Recycling; Substitutes
documents:
- title: 'Wikipedia: Indium phosphide (formula, crystal structure, manufacturing, uses)'
type: database
url: https://en.wikipedia.org/wiki/Indium_phosphide
year: 2026
- title: 'Shalomeo: InP single crystal substrates, product page (specifications and basic properties)'
type: datasheet
url: https://www.shalomeo.com/Ceramic-Substrates/InP-Semi-Growth/product-257.html
- title: 'Surfacenet: Indium phosphide (InP) material properties page'
type: database
url: https://surfacenet.de/files/old_version/html/inp.html
- title: 'PubChem compound record: Indium phosphide (CID 31170), GHS classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/Indium-phosphide
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Indium'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-indium.pdf
year: 2026
- title: 'USGS: About the 2025 List of Critical Minerals'
type: report
url: https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals
year: 2025
- title: 'European Commission: Critical raw materials'
type: report
url: https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en
year: 2024
- title: 'Wikipedia: Indium gallium arsenide (lattice matching to InP, photodiode range)'
type: database
url: https://en.wikipedia.org/wiki/Indium_gallium_arsenide
year: 2026
gaps:
- No space flight, vacuum, thermal-cycling or radiation-dose result for InP was found. The space statements come from one supplier (good radiation stability, radiation-resistant solar cells) and carry no numbers.
- Space group, dielectric constant, thermal expansion and effective masses were not found on any page opened. The Ioffe Institute semiconductor table returned a certificate error and could not be opened.
- Carrier concentration, mobility ratio and dislocation density for undoped, S-doped, Zn-doped and Fe-doped InP are printed on the Shalomeo page without units, and Surfacenet flattens the exponents, so none is recorded.
- 'Melting point is not resolved: 1062 °C (Shalomeo, Wikipedia) against 1330 °C (Surfacenet, degree sign garbled). Both are recorded.'
- 'Electron mobility is not resolved: 5400 cm2/(V·s) at 300 K (Shalomeo) against 3700 to 4000 cm2/ V-S for undoped N-type (100) crystal (Surfacenet). The conditions differ.'
- Atomic weights of indium and phosphorus were not printed on any page opened, so the recipe parts carry atom counts only.
- The Wikipedia manufacturing section gives a temperature for the white-phosphorus route. It is not recorded as a property because Wikipedia is used here for composition and history only, so the story describes the route without the figure.
- Phosphorus supply, crustal abundance of indium and the indium price were not recorded. The USGS 2026 summary prints the 2025 U.S. warehouse price as 370 and as 390 dollars per kilogram in different places, so neither is used.
- No supplier safety data sheet for InP was opened (the American Elements page returned HTTP 403). Hazard data rest on the PubChem ECHA summary, and no toxicology values are recorded.
- Corrosion and ageing are described only by a qualitative supplier statement about acids and one about radiation stability. No oxidation, humidity or thermal ageing study was opened.
- Standard designations (UNS, EN, DIN, JIS, ASTM) were not found for InP substrates, so identity.designations is left out.
- Failure modes, side effects and mitigations for InP devices were not found in the sources read.
- Molar mass, band gap, electron mobility and lattice constant are not in spores/property-canon.yaml and use snake_case names.
- No images are added to this profile.
sources:
wikipedia-inp:
title: Indium phosphide (Wikipedia)
url: https://en.wikipedia.org/wiki/Indium_phosphide
year: 2026
kind: web
license: CC BY-SA 4.0 (cited, not reproduced)
shalomeo-inp:
title: Indium Phosphide (InP) single crystal substrates, InP-Semi-Growth product page (Shalomeo)
url: https://www.shalomeo.com/Ceramic-Substrates/InP-Semi-Growth/product-257.html
kind: datasheet
license: Manufacturer product page (cited, not reproduced)
surfacenet-inp:
title: Indium phosphide (InP) material properties (Surfacenet, old-version page)
url: https://surfacenet.de/files/old_version/html/inp.html
kind: database
license: cited, not reproduced
pubchem-inp:
title: 'PubChem compound record: Indium phosphide (CID 31170), including ECHA C&L Inventory classification'
id: CID 31170; CAS 22398-80-7
url: https://pubchem.ncbi.nlm.nih.gov/compound/Indium-phosphide
year: 2026
kind: database
license: PubChem (NCBI), public domain; ECHA sections attributed in the record
usgs-mcs2026-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-crit2025:
title: About the 2025 List of Critical Minerals (USGS)
id: Final 2025 List of Critical Minerals, November 2025
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)
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
wikipedia-ingaas:
title: Indium gallium arsenide (Wikipedia)
url: https://en.wikipedia.org/wiki/Indium_gallium_arsenide
year: 2026
kind: web
license: CC BY-SA 4.0 (cited, not reproduced)
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 13
unreachable: 2
caveats: 4
note: 'Written by an AI assistant on 2026-11-01 from pages read in this run: Wikipedia (composition, CAS, manufacturing routes, uses), the Shalomeo and Surfacenet property pages (read through text extraction), PubChem (molecular weight and GHS summary via its data service), the USGS 2026 indium summary (PDF text extracted), the USGS and EU critical-list pages, and the Wikipedia InGaAs article. Unreachable: the Ioffe Institute InP table (certificate error) and American Elements (HTTP 403). Caveats: the Surfacenet melting point and mobility disagree with Shalomeo; the Surfacenet degree sign is garbled; all supplier numbers are one manufacturer''s data.'
story:
recipe:
line: 'Indium phosphide is a binary compound of one indium atom and one phosphorus atom, with the formula InP (PubChem). It crystallises in the zinc-blende structure (Wikipedia). Wikipedia lists three routes: reacting white phosphorus with indium iodide at high temperature, direct combination of purified indium and phosphorus at high temperature and pressure, and thermal decomposition of a trialkyl indium compound mixed with phosphine.'
parts:
- name: Indium
symbol: In
role: The group III element. Indium gallium arsenide replaces part of this indium with gallium so that the alloy matches the InP lattice.
- name: Phosphorus
symbol: P
role: The group V element. One phosphorus atom per formula unit, in the tetrahedral coordination that the supplier table prints.
risk_groups:
- title: For people
level: 2
verdict: Cancer classification in most reports
lead: PubChem's ECHA summary classifies indium phosphide as a cancer hazard in most reports that give codes. The classification varies between notifications, and no supplier safety data sheet was opened.
points:
- label: Classification
line: PubChem's ECHA summary covers 211 company reports from 8 notifications. Of the reports that give codes, 98.1% list H350 (May cause cancer), 94.3% list H361 (Suspected of damaging fertility or the unborn child) and 98.1% list H372 (Causes damage to organs through prolonged or repeated exposure). The signal word is Danger.
- label: Other notifications
line: One notification reads Not Classified. Others list H350 and H372 with the signal word Danger.
- label: Wafer packing
line: Shalomeo packs its substrates in class 100 bags inside a class 1000 clean room. That is the only supplier handling statement that was read.
- title: In service
lead: No space failure data for InP were found. The radiation statements that were read carry no numbers.
points:
- label: Radiation
line: Shalomeo says InP has good radiation stability, but it gives no dose, fluence or test result for that claim.
- label: Surface
line: Shalomeo gives a surface roughness of Ra ≤5 Å for polished substrates, printed as Ra:≤5A.
- title: Handling and storage
points:
- label: Packaging
line: Shalomeo ships the substrates in class 100 bags inside a class 1000 clean room. Keep them in those bags until use.
why: Indium phosphide (InP) is a III-V semiconductor, made of indium and phosphorus in a 1:1 ratio, that is sold as a single-crystal substrate. Shalomeo lists its features as high electron mobility, good radiation stability and a large band gap, and gives a band gap of 1.344 eV at 300 K and an electron mobility of 5400 cm2/(V·s) at 300 K. Its main role is as the substrate for indium gallium arsenide, because the In0.53Ga0.47As alloy matches the InP lattice (Wikipedia).
uses:
- where: Photodiodes and detectors
line: Most InGaAs devices are grown on InP substrates. For 1.1 μm to 1.7 μm, GaInAs photodiodes are the preferred choice, and the 53% indium composition has a cut-off of 1.68 μm at 295 K (Wikipedia).
- where: High-frequency transistors
line: Shalomeo says InP performs superiorly in high-power and high-frequency electronics. Wikipedia reports pseudomorphic heterojunction bipolar transistors that could operate at 604 GHz.
- where: Telecom lasers and receivers
line: USGS reports that InP lasers and receivers send data through fiber-optic lines in 5G networks, and that InP is used in high-speed photodetectors and laser diodes for optical communications.
can_do:
- label: Electron speed
benchmark: electron_mobility
value: 5400 cm2/(V·s) at 300 K
line: Electron mobility is 5400 cm2/(V·s) at 300 K (Shalomeo). Surfacenet gives 3700 to 4000 cm2/ V-S for undoped N-type (100) crystal, so the exact figure depends on the material and its conditions.
- label: Band gap
benchmark: band_gap
value: 1.344 eV at 300 K
line: The band gap is 1.344 eV at 300 K (Shalomeo). The Wikipedia infobox describes this gap as direct.
- label: Lattice match
benchmark: lattice_constant
value: 5.869 Å
line: The lattice constant is 5.869 Å (Shalomeo). Wikipedia gives 5.869 Å at 295 K for the In0.53Ga0.47As alloy, which matches InP at that temperature.
- label: Heat conduction
benchmark: thermal_conductivity
value: 0.68 W/(cm·K)
line: Thermal conductivity is 0.68 W/(cm·K) at 300 K (Shalomeo).
compare: Indium phosphide sits with the other III-V compound semiconductors in this collection. Compared with gallium arsenide, the figures we hold put InP at a smaller band gap and a lower electron mobility at 300 K. InP's main role is as the substrate on which InGaAs devices are grown. The table compares InP with the other semiconductors in this collection on density, band gap and electron mobility.
compare_rows:
- label: Density
benchmark: density
- label: Band gap
benchmark: band_gap
- label: Electron mobility
benchmark: electron_mobility
handling:
- Treat the material as a cancer hazard until the supplier's safety data sheet says otherwise, because PubChem's ECHA summary gives H350 for 98.1% of reports that list codes.
- Keep substrates in the clean-room bags they are shipped in until use.
- Get the supplier's safety data sheet before cutting, etching or grinding InP.
good_for:
- Substrates for InGaAs detectors and photodiodes, where the InP lattice matches In0.53Ga0.47As at 295 K.
- High-frequency transistors. Wikipedia reports pseudomorphic transistors that could operate at 604 GHz.
- Telecom lasers and receivers, which USGS says carry fiber-optic traffic in 5G networks.
watch_out:
- 'Cancer classification: PubChem''s ECHA summary gives H350 for 98.1% of reports that list codes.'
- 'Supply: China produced 70% of world indium (USGS), China added indium to new export restrictions in February 2025, and the United States imports all of its indium.'
- 'Melting point: 1062 °C from Shalomeo and Wikipedia, but 1330 °C from Surfacenet.'
- No space flight or radiation-dose data for InP were found, so the space case rests on supplier statements.
verdict: InP is the lattice-matched substrate for InGaAs detectors and a fast-electron material for high-frequency and telecom devices. The supplier and database pages agree on density, band gap and lattice constant, but they disagree on the melting point, and the mobility figures need their conditions. The cancer classification and dependence on Chinese indium supply are the points to watch. This profile has no space flight data.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Indium phosphide (Wikipedia) | web | 2026 | 1 value | |
| Indium Phosphide (InP) single crystal substrates, InP-Semi-Growth product page (Shalomeo) | datasheet | 13 values | ||
| Indium phosphide (InP) material properties (Surfacenet, old-version page) | database | 5 values | ||
| PubChem compound record: Indium phosphide (CID 31170), including ECHA C&L Inventory classification | database | 2026 | 3 values | |
| Mineral Commodity Summaries 2026, Indium | report | 2026 | 2 values | |
| About the 2025 List of Critical Minerals (USGS) | web | 2025 | 0 values | |
| Critical raw materials (European Commission) | web | 2024 | 0 values | |
| Indium gallium arsenide (Wikipedia) | web | 2026 | 1 value |
Updated