List of semiconductor materials

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Semiconductor materials are nominally small band gap insulators. The defining property of a semiconductor material is that it can be doped with impurities that alter its electronic properties in a controllable way.[citation needed]

Because of their application in the computer and photovoltaic industry—in devices such as transistors, lasers and solar cells—the search for new semiconductor materials and the improvement of existing materials is an important field of study in materials science.

Most commonly used semiconductor materials are crystalline inorganic solids. These materials are classified according to the periodic table groups of their constituent atoms.

Different semiconductor materials differ in their properties. Thus, in comparison with silicon, compound semiconductors have both advantages and disadvantages. For example, gallium arsenide (GaAs) has six times higher electron mobility than silicon, which allows faster operation; wider band gap, which allows operation of power devices at higher temperatures, and gives lower thermal noise to low power devices at room temperature; its direct band gap gives it more favorable optoelectronic properties than the indirect band gap of silicon; it can be alloyed to ternary and quaternary compositions, with adjustable band gap width, allowing light emission at chosen wavelengths, and allowing e.g. matching to wavelengths with lowest losses in optical fibers. GaAs can be also grown in a semi-insulating form, which is suitable as a lattice-matching insulating substrate for GaAs devices. Conversely, silicon is robust, cheap, and easy to process, whereas GaAs is brittle and expensive, and insulation layers can not be created by just growing an oxide layer; GaAs is therefore used only where silicon is not sufficient.[1]

By alloying multiple compounds, some semiconductor materials are tunable, e.g., in band gap or lattice constant. The result is ternary, quaternary, or even quinary compositions. Ternary compositions allow adjusting the band gap within the range of the involved binary compounds; however, in case of combination of direct and indirect band gap materials there is a ratio where indirect band gap prevails, limiting the range usable for optoelectronics; e.g. AlGaAs LEDs are limited to 660 nm by this. Lattice constants of the compounds also tend to be different, and the lattice mismatch against the substrate, dependent on the mixing ratio, causes defects in amounts dependent on the mismatch magnitude; this influences the ratio of achievable radiative/nonradiative recombinations and determines the luminous efficiency of the device. Quaternary and higher compositions allow adjusting simultaneously the band gap and the lattice constant, allowing increasing radiant efficiency at wider range of wavelengths; for example AlGaInP is used for LEDs . Materials transparent to the generated wavelength of light are advantageous, as this allows more efficient extraction of photons from the bulk of the material. That is, in such transparent materials, light production is not limited to just the surface. Index of refraction is also composition-dependent and influences the extraction efficiency of photons from the material.[2]

Types of semiconductor materials[edit]

Table of semiconductor materials[edit]

GroupElem.MaterialFormulaBand gap (eV)Gap typeDescription
IV1DiamondC5.47[3][4]indirectExcellent thermal conductivity. Superior mechanical and optical properties. Extremely high mechanical quality factor.[5]
IV1SiliconSi1.12[3][4]indirectUsed in conventional crystalline silicon (c-Si) solar cells, and in its amorphous form as amorphous silicon (a-Si) in thin film solar cells. Most common semiconductor material in photovoltaics; dominates worldwide PV market; easy to fabricate; good electrical and mechanical properties. Forms high quality thermal oxide for insulation purposes.
IV1GermaniumGe0.67[3][4]indirectUsed in early radar detection diodes and first transistors; requires lower purity than silicon. A substrate for high-efficiency multijunction photovoltaic cells. Very similar lattice constant to gallium arsenide. High-purity crystals used for gamma spectroscopy. May grow whiskers, which impair reliability of some devices.
IV1Gray tin, α-SnSn0.00,[6] 0.08[7]indirectLow temperature allotrope (diamond cubic lattice).
IV2Silicon carbide, 3C-SiCSiC2.3[3]indirectused for early yellow LEDs
IV2Silicon carbide, 4H-SiCSiC3.3[3]indirect
IV2Silicon carbide, 6H-SiCSiC3.0[3]indirectused for early blue LEDs
VI1Sulfur, α-SS82.6[8]
VI1Gray seleniumSe1.74Used in selenium rectifiers.
VI1TelluriumTe0.33
III-V2Boron nitride, cubicBN6.36[9]indirectpotentially useful for ultraviolet LEDs
III-V2Boron nitride, hexagonalBN5.96[9]quasi-directpotentially useful for ultraviolet LEDs
III-V2Boron nitride nanotubeBN~5.5
III-V2Boron phosphideBP2indirect
III-V2Boron arsenideBAs1.5indirectResistant to radiation damage, possible applications in betavoltaics.
III-V2Boron arsenideB12As23.47indirectResistant to radiation damage, possible applications in betavoltaics.
III-V2Aluminium nitrideAlN6.28[3]directPiezoelectric. Not used on its own as a semiconductor; AlN-close GaAlN possibly usable for ultraviolet LEDs. Inefficient emission at 210 nm was achieved on AlN.
III-V2Aluminium phosphideAlP2.45[4]indirect
III-V2Aluminium arsenideAlAs2.16[4]indirect
III-V2Aluminium antimonideAlSb1.6/2.2[4]indirect/direct
III-V2Gallium nitrideGaN3.44[3][4]directproblematic to be doped to p-type, p-doping with Mg and annealing allowed first high-efficiency blue LEDs[2] and blue lasers. Very sensitive to ESD. Insensitive to ionizing radiation, suitable for spacecraft solar panels. GaN transistors can operate at higher voltages and higher temperatures than GaAs, used in microwave power amplifiers. When doped with e.g. manganese, becomes a magnetic semiconductor.
III-V2Gallium phosphideGaP2.26[3][4]indirectUsed in early low to medium brightness cheap red/orange/green LEDs. Used standalone or with GaAsP. Transparent for yellow and red light, used as substrate for GaAsP red/yellow LEDs. Doped with S or Te for n-type, with Zn for p-type. Pure GaP emits green, nitrogen-doped GaP emits yellow-green, ZnO-doped GaP emits red.
III-V2Gallium arsenideGaAs1.43[3][4]directsecond most common in use after silicon, commonly used as substrate for other III-V semiconductors, e.g. InGaAs and GaInNAs. Brittle. Lower hole mobility than Si, P-type CMOS transistors unfeasible. High impurity density, difficult to fabricate small structures. Used for near-IR LEDs, fast electronics, and high-efficiency solar cells. Very similar lattice constant to germanium, can be grown on germanium substrates.
III-V2Gallium antimonideGaSb0.726[3][4]directUsed for infrared detectors and LEDs and thermophotovoltaics. Doped n with Te, p with Zn.
III-V2Indium nitrideInN0.7[3]directPossible use in solar cells, but p-type doping difficult. Used frequently as alloys.
III-V2Indium phosphideInP1.35[3]directCommonly used as substrate for epitaxial InGaAs. Superior electron velocity, used in high-power and high-frequency applications. Used in optoelectronics.
III-V2Indium arsenideInAs0.36[3]directUsed for infrared detectors for 1–3.8 µm, cooled or uncooled. High electron mobility. InAs dots in InGaAs matrix can serve as quantum dots. Quantum dots may be formed from a monolayer of InAs on InP or GaAs. Strong photo-Dember emitter, used as a terahertz radiation source.
III-V2Indium antimonideInSb0.17[3]directUsed in infrared detectors and thermal imaging sensors, high quantum efficiency, low stability, require cooling, used in military long-range thermal imager systems. AlInSb-InSb-AlInSb structure used as quantum well. Very high electron mobility, electron velocity and ballistic length. Transistors can operate below 0.5V and above 200 GHz. Terahertz frequencies maybe achievable.
II-VI2Cadmium selenideCdSe1.74[4]directNanoparticles used as quantum dots. Intrinsic n-type, difficult to dope p-type, but can be p-type doped with nitrogen. Possible use in optoelectronics. Tested for high-efficiency solar cells.
II-VI2Cadmium sulfideCdS2.42[4]directUsed in photoresistors and solar cells; CdS/Cu2S was the first efficient solar cell. Used in solar cells with CdTe. Common as quantum dots. Crystals can act as solid-state lasers. Electroluminescent. When doped, can act as a phosphor.
II-VI2Cadmium tellurideCdTe1.49[4]Used in solar cells with CdS. Used in thin film solar cells and other cadmium telluride photovoltaics; less efficient than crystalline silicon but cheaper. High electro-optic effect, used in electro-optic modulators. Fluorescent at 790 nm. Nanoparticles usable as quantum dots.
II-VI, oxide2Zinc oxideZnO3.37[4]directPhotocatalytic. Bandwidth tunable from 3 to 4 eV by alloying with magnesium oxide and cadmium oxide. Intrinsic n-type, p-type doping is difficult. Heavy aluminium, indium, or gallium doping yields transparent conductive coatings; ZnO:Al is used as window coatings transparent in visible and reflective in infrared region and as conductive films in LCD displays and solar panels as a replacement of indium tin oxide. Resistant to radiation damage. Possible use in LEDs and laser diodes. Possible use in random lasers.
II-VI2Zinc selenideZnSe2.7[4]directUsed for blue lasers and LEDs. Easy to n-type doping, p-type doping is difficult but can be done with e.g. nitrogen. Common optical material in infrared optics.
II-VI2Zinc sulfideZnS3.54/3.91[4]directBand gap 3.54 eV (cubic), 3.91 (hexagonal). Can be doped both n-type and p-type. Common scintillator/phosphor when suitably doped.
II-VI2Zinc tellurideZnTe2.25[4]directCan be grown on AlSb, GaSb, InAs, and PbSe. Used in solar cells, compoments of microwave generators, blue LEDs and lasers. Used in electrooptics. Together with lithium niobate used to generate terahertz radiation.
I-VII2Cuprous chlorideCuCl3.4[10]direct
I-VI2Copper sulfideCu2S1.2directp-type, Cu2S/CdS was the first efficient thin film solar cell
IV-VI2Lead selenidePbSe0.27directUsed in infrared detectors for thermal imaging. Nanocrystals usable as quantum dots.
IV-VI2Lead(II) sulfidePbS0.37Mineral galena, first semiconductor in practical use, used in cat's whisker detectors; the detectors are slow due to high dielectric constant of PbS. Oldest material used in infrared detectors. At room temperature can detect SWIR, longer wavelengths require cooling.
IV-VI2Lead telluridePbTe0.32Low thermal conductivity, good thermoelectric material.
IV-VI2Tin sulfideSnS1.3/1.0[11]direct/indirectTin sulfide (SnS) is a semiconductor with direct optical band gap of 1.3 eV and absorption coefficient above 104 cm-1 for photon energies above 1.3 eV. It is a p-type semiconductor whose electrical properties can be tailored by doping and structural modification and has emerged as one of the simple, non-toxic and affordable material for thin films solar cells since a decade.
IV-VI2Tin sulfideSnS22.2
IV-VI2Tin tellurideSnTeComplex band structure.
IV-VI3Lead tin telluridePbSnTeUsed in infrared detectors and for thermal imaging.
IV-VI3Thallium tin tellurideTl2SnTe5
IV-VI3Thallium germanium tellurideTl2GeTe5
V-VI, layered2Bismuth tellurideBi2Te3Efficient thermoelectric material when alloyed with selenium or antimony. Narrow-gap layered semiconductor. High electrical conductivity, low thermal conductivity. Topological insulator.
II-V2Cadmium phosphideCd3P2
II-V2Cadmium arsenideCd3As20.14N-type intrinsic semiconductor. Very high electron mobility. Used in infrared detectors, photodetectors, dynamic thin-film pressure sensors, and magnetoresistors.
II-V2Cadmium antimonideCd3Sb2
II-V2Zinc phosphideZn3P2
II-V2Zinc arsenideZn3As2
II-V2Zinc antimonideZn3Sb2Used in infrared detectors and thermal imagers, transistors, and magnetoresistors.
Oxide2Titanium dioxide, anataseTiO23.2indirectphotocatalytic, n-type
Oxide2Titanium dioxide, rutileTiO23.02directphotocatalytic, n-type
Oxide2Titanium dioxide, brookiteTiO22.96[12]
Oxide2Copper(I) oxideCu2O2.17 [13]One of the most studied semiconductors. Many applications and effects first demonstrated with it. Formerly used in rectifier diodes, before silicon.
Oxide2Copper(II) oxideCuO1.2P-type semiconductor.
Oxide2Uranium dioxideUO21.3High Seebeck coefficient, resistant to high temperatures, promising thermoelectric and thermophotovoltaic applications. Formerly used in URDOX resistors, conducting at high temperature. Resistant to radiation damage.
Oxide2Uranium trioxideUO3
Oxide2Bismuth trioxideBi2O3Ionic conductor, applications in fuel cells.
Oxide2Tin dioxideSnO23.7Oxygen-deficient n-type semiconductor. Used in gas sensors.
Oxide3Barium titanateBaTiO33Ferroelectric, piezoelectric. Used in some uncooled thermal imagers. Used in nonlinear optics.
Oxide3Strontium titanateSrTiO33.3Ferroelectric, piezoelectric. Used in varistors. Conductive when niobium-doped.
Oxide3Lithium niobateLiNbO34Ferroelectric, piezoelectric, shows Pockels effect. Wide uses in electrooptics and photonics.
Oxide3Lanthanum copper oxideLa2CuO42superconductive when doped with barium or strontium
Layered2Lead(II) iodidePbI2
Layered2Molybdenum disulfideMoS2
Layered2Gallium selenideGaSe2.1indirectPhotoconductor. Uses in nonlinear optics.
Layered2Tin sulfideSnS
Layered2Bismuth sulfideBi2S3
Magnetic, diluted (DMS)[14]3Gallium manganese arsenideGaMnAs
Magnetic, diluted (DMS)3Indium manganese arsenideInMnAs
Magnetic, diluted (DMS)3Cadmium manganese tellurideCdMnTe
Magnetic, diluted (DMS)3Lead manganese telluridePbMnTe
Magnetic4Lanthanum calcium manganateLa0.7Ca0.3MnO3colossal magnetoresistance
Magnetic2Iron(II) oxideFeOantiferromagnetic
Magnetic2Nickel(II) oxideNiOantiferromagnetic
Magnetic2Europium(II) oxideEuOferromagnetic
Magnetic2Europium(II) sulfideEuSferromagnetic
Magnetic2Chromium(III) bromideCrBr3
other3Copper indium selenide, CISCuInSe21direct
other3Silver gallium sulfideAgGaS2nonlinear optical properties
other3Zinc silicon phosphideZnSiP2
other2Arsenic sulfideAs2S3semiconductive in both crystalline and glassy state
other2Platinum silicidePtSiUsed in infrared detectors for 1–5 µm. Used in infrared astronomy. High stability, low drift, used for measurements. Low quantum efficiency.
other2Bismuth(III) iodideBiI3
other2Mercury(II) iodideHgI2Used in some gamma-ray and x-ray detectors and imaging systems operating at room temperature.
other2Thallium(I) bromideTlBrUsed in some gamma-ray and x-ray detectors and imaging systems operating at room temperature. Used as a real-time x-ray image sensor.
other2Silver sulfideAg2S0.9 [15]
other2Iron disulfideFeS20.95Mineral pyrite. Used in later cat's whisker detectors, investigated for solar cells.
other4Copper zinc tin sulfide, CZTSCu2ZnSnS41.49directCu2ZnSnS4 is derived from CIGS, replacing the Indium/Gallium with earth abundant Zinc/Tin.
other4Copper zinc antimony sulfide, CZASCu1.18Zn0.40Sb1.90S7.22.2[16]directCopper zinc antimony sulfide is derived from copper antimony sulfide (CAS), a famatinite class of compound.

Table of semiconductor alloy systems[edit]

The following semiconducting systems can be tuned to some extent, and represent not a single material but a class of materials.

GroupElem.Material classFormulaBand gap (eV) lowerupperGap typeDescription
IV2Silicon-germaniumSi1-xGex0.671.11[3]indirectadjustable band gap, allows construction of heterojunction structures. Certain thicknesses of superlattices have direct band gap.[17]
IV2Silicon-tinSi1-xSnx1.01.11indirectAdjustable band gap.[18]
III-V3Aluminium gallium arsenideAlxGa1-xAs1.422.16[3]direct/indirectdirect band gap for x<0.4 (corresponding to 1.42–1.95 eV); can be lattice-matched to GaAs substrate over entire composition range; tends to oxidize; n-doping with Si, Se, Te; p-doping with Zn, C, Be, Mg.[2] Can be used for infrared laser diodes. Used as a barrier layer in GaAs devices to confine electrons to GaAs (see e.g. QWIP). AlGaAs with composition close to AlAs is almost transparent to sunlight. Used in GaAs/AlGaAs solar cells.
III-V3Indium gallium arsenideInxGa1-xAs0.361.43directWell-developed material. Can be lattice matched to InP substrates. Use in infrared technology and thermophotovoltaics. Indium content determines charge carrier density. For x=0.015, InGaAs perfectly lattice-matches germanium; can be used in multijunction photovoltaic cells. Used in infrared sensors, avalanche photodiodes, laser diodes, optical fiber communication detectors, and short-wavelength infrared cameras.
III-V3Indium gallium phosphideInxGa1-xP1.352.26direct/indirectused for HEMT and HBT structures and high-efficiency multijunction solar cells for e.g. satellites. Ga0.5In0.5P is almost lattice-matched to GaAs, with AlGaIn used for quantum wells for red lasers.
III-V3Aluminium indium arsenideAlxIn1-xAs0.362.16direct/indirectBuffer layer in metamorphic HEMT transistors, adjusting lattice constant between GaAs substrate and GaInAs channel. Can form layered heterostructures acting as quantum wells, in e.g. quantum cascade lasers.
III-V3Aluminium indium antimonideAlxIn1-xSb
III-V3Gallium arsenide nitrideGaAsN
III-V3Gallium arsenide phosphideGaAsP1.432.26direct/indirectUsed in red, orange and yellow LEDs. Often grown on GaP. Can be doped with nitrogen.
III-V3Gallium arsenide antimonideGaAsSb0.71.42[3]direct
III-V3Aluminium gallium nitrideAlGaN3.446.28directUsed in blue laser diodes, ultraviolet LEDs (down to 250 nm), and AlGaN/GaN HEMTs. Can be grown on sapphire. Used in heterojunctions with AlN and GaN.
III-V3Aluminium gallium phosphideAlGaP2.262.45indirectUsed in some green LEDs.
III-V3Indium gallium nitrideInGaN23.4directInxGa1–xN, x usually between 0.02–0.3 (0.02 for near-UV, 0.1 for 390 nm, 0.2 for 420 nm, 0.3 for 440 nm). Can be grown epitaxially on sapphire, SiC wafers or silicon. Used in modern blue and green LEDs, InGaN quantum wells are effective emitters from green to ultraviolet. Insensitive to radiation damage, possible use in satellite solar cells. Insensitive to defects, tolerant to lattice mismatch damage. High heat capacity.
III-V3Indium arsenide antimonideInAsSb
III-V3Indium gallium antimonideInGaSb
III-V4Aluminium gallium indium phosphideAlGaInPdirect/indirectalso InAlGaP, InGaAlP, AlInGaP; for lattice matching to GaAs substrates the In mole fraction is fixed at about 0.48, the Al/Ga ratio is adjusted to achieve band gaps between about 1.9 and 2.35 eV; direct or indirect band gaps depending on the Al/Ga/In ratios; used for waveengths between 560–650 nm; tends to form ordered phases during deposition, which has to be prevented[2]
III-V4Aluminium gallium arsenide phosphideAlGaAsP
III-V4Indium gallium arsenide phosphideInGaAsP
III-V4Indium gallium arsenide antimonideInGaAsSbUse in thermophotovoltaics.
III-V4Indium arsenide antimonide phosphideInAsSbPUse in thermophotovoltaics.
III-V4Aluminium indium arsenide phosphideAlInAsP
III-V4Aluminium gallium arsenide nitrideAlGaAsN
III-V4Indium gallium arsenide nitrideInGaAsN
III-V4Indium aluminium arsenide nitrideInAlAsN
III-V4Gallium arsenide antimonide nitrideGaAsSbN
III-V5Gallium indium nitride arsenide antimonideGaInNAsSb
III-V5Gallium indium arsenide antimonide phosphideGaInAsSbPCan be grown on InAs, GaSb, and other substrates. Can be lattice matched by varying composition. Possibly usable for mid-infrared LEDs.
II-VI3Cadmium zinc telluride, CZTCdZnTe1.42.2directEfficient solid-state x-ray and gamma-ray detector, can operate at room temperature. High electro-optic coefficient. Used in solar cells. Can be used to generate and detect terahertz radiation. Can be used as a substrate for epitaxial growth of HgCdTe.
II-VI3Mercury cadmium tellurideHgCdTe01.5Known as "MerCad". Extensive use in sensitive cooled infrared imaging sensors, infrared astronomy, and infrared detectors. Alloy of mercury telluride (a semimetal, zero band gap) and CdTe. High electron mobility. The only common material capable of operating in both 3–5 µm and 12–15 µm atmospheric windows. Can be grown on CdZnTe.
II-VI3Mercury zinc tellurideHgZnTe02.25Used in infrared detectors, infrared imaging sensors, and infrared astronomy. Better mechanical and thermal properties than HgCdTe but more difficult to control the composition. More difficult to form complex heterostructures.
II-VI3Mercury zinc selenideHgZnSe
other4Copper indium gallium selenide, CIGSCu(In,Ga)Se211.7directCuInxGa1–xSe2. Polycrystalline. Used in thin film solar cells.

See also[edit]

References[edit]

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