Misalan semiconductors. Nau'in, Properties, m aikace-aikace

Mafi shahara ne semiconductor silicon (Si). Amma baya daga gare shi, akwai mutane da yawa wasu. Misalai ne na halitta, wannan semiconductor kayan matsayin blende (ZnS), cuprite (Cu ₂ Ya), galena (PBS) da kuma da yawa wasu. The iyali na semiconductors, ciki har da semiconductors shirya a dakunan gwaje-gwaje, wakiltar daya daga cikin mafi bambancin azuzuwan na kayan sani ga mutum.

Faye hali na semiconductors

Na 104 abubuwa na lokaci-lokaci tebur ne karafa 79, 25 - nonmetals daga wanda 13 sinadaran abubuwa mallaka semiconducting dũkiyarsu da kuma 12 - dielectric. Main semiconductor fasalin kunshi a cewa su watsin qara muhimmanci tare da kara yawan zafin jiki. A low yanayin zafi, da suka nuna hali kamar insulators, kuma a high - kamar yadda conductors. Wadannan semiconductors ne daban-daban daga karfe: karfe juriya qara proportionally da karuwa a yawan zafin jiki.

Wani bambanci daga semiconductor karfe ne cewa da juriya na semiconductor rage-rage a ƙarƙashin rinjayar haske, yayin da a cikin karshen karfe ne ba ya canzawa. Har ila yau da watsin da semiconductors dabam a lokacin da gudanar da su a qananan adadin kazamta.

Semiconductors ake samu tsakanin sinadaran mahadi da daban-daban crystal Tsarin. Wadannan iya zama abubuwa kamar silicon da kuma selenium, ko biyu mahadi kamar gallium arsenide. Mutane da yawa gudanar da mahadi, kamar polyacetylene, (CH) _n, - semiconductor kayan. Wasu semiconductors nuna Magnetic (CD _1-x mn _x Te) ko ferroelectric Properties (SbSI). Sauran alloying da isa zama superconductors (GeTe da SrTiO _3). Mutane da yawa daga cikin sabon bincike high-zazzabi superconductors da ƙarfe semiconducting lokaci. Alal misali, La ₂ CuO ₄ ne a semiconductor, amma da samuwar gami da Sr zama sverhrovodnikom (La _1-x Sr _{x) 2} CuO _4.

Physics litattafan ba definition matsayin semiconductor abu da wani lantarki resistivity na daga 10 ^-4 zuwa 10 ⁷ ohms · m. Zai yiwu madadin definition. Da nisa daga alfarma band na semiconductor - daga 0 zuwa 3 maddî. Karafa da semimetals - wani abu da sifili makamashi rata, da dũkiyõyinsu a wadda ta wuce W maddî kira insulators. Akwai ware. Alal misali, a semiconductor lu'u-lu'u yana da fadi da haramta zone 6 maddî, a Semi-insulating GaAs - 1,5 maddî. Gan, wani abu don optoelectronic na'urorin a blue yankin, yana mai alfarma band nisa 3.5 maddî.

da makamashi rata

Valence orbitals na kwayoyin halitta a cikin crystal raga ya kasu kashi biyu kungiyoyin na makamashi matakan - a free zone, ayi a matakin qarshe, kuma kayyade lantarki watsin na semiconductors, da kuma valence band, a kasa. Wadannan matakai, dangane da fasali na crystal raga tsarin da kwayoyin halitta iya rarraba ko a spaced daga juna. A karshen harka akwai wani makamashi rata, ko a cikin wasu kalmomi, tsakanin haramta band zones.

The location da kuma cika matakin ne m da conductive Properties daga cikin abu. A cewar wannan siffa abu raba da conductors, insulators, kuma semiconductors. Da nisa daga alfarma band na semiconductor dabam 0.01-3 maddî, da makamashi rata na dielectric fiye da 3 maddî. Metals saboda da zoba da makamashi gibba matakan ne ba.

Semiconductors da insulators, da bambanci ga karafa, da electrons suna cike valence band kuma mafi kusa free zone, ko da madugu band, da valence makamashi ne masu garu kashe daga katsewa - rabo daga haramta kuzari na electrons.

A dielectrics thermal makamashi ko negligible lantarki filin bai isa ya sa Jump ta hanyar wannan rata, da electrons ba batun da madugu band. Bã su iya don motsawa ta cikin crystal raga da kuma zama yan dako na lantarki.

Karfafa lantarki watsin, wani electron a valence matakin ya kamata a ba da makamashi, wanda zai zama isa ya shawo kan makamashi rata. Kawai a lokacin da adadin kuzari sha ne ba karami fiye da darajar da makamashi rata, zai wuce daga valence electron matakin a kan madugu matakin.

A wannan yanayin, idan da nisa daga cikin makamashi rata wuce 4 maddî, watsin semiconductor zumudi sakawa a iska mai guba ko dumama ne kusan ba zai yiwu - da zumudi makamashi na electrons a da narkewa zafin jiki ne ba su isa ba tsalle da makamashi rata ta hanyar da zone. Lokacin da mai tsanani, da crystal yakan narke a gaban lantarki watsin. Irin wannan abubuwa sun hada da ma'adini (de = 5,2 maddî), lu'u-lu'u (de = 5,1 maddî), da yawa salts.

Extrinsic kuma muhimmi watsin semiconductor

Net semiconductor lu'ulu'u da muhimmi watsin. Irin wannan semiconductors dace sunayen. Muhimmi semiconductor ƙunshi wani daidaita yawan ramukan da kuma free electrons. Lokacin da dumama muhimmi watsin na semiconductors ƙaruwa. A m zazzabi, akwai wani yanayin tsauri ma'auni adadin generated electron-rami da nau'i-nau'i da kuma yawan recombining electrons da ramuka, wanda haƙuri a karkashin wadannan yanayi.

A gaban impurities muhimmanci rinjayar da lantarki watsin na semiconductors. Ƙara su damar ƙwarai kara yawan free electrons a kananan yawan ramukan da kuma kara yawan ramukan da wani karamin yawan electrons a madugu matakin. Kazamta semiconductors - da conductors da ciwon da kazamta watsin.

Impurities ana iya ba da sadaka electrons ake kira bayarwa. Bayarwa impurities iya zama sinadaran abubuwa da kwayoyin halitta, da valence matakan wadda dauke da karin electrons fiye da sunadaran da tushe abu. Alal misali, phosphorus da bismuth - wani silicon bayarwa impurities.

A samar da makamashi da ake bukata domin Jump na wani electron a madugu yankin, aka kira kunnawa makamashi. Kazamta semiconductor bukatar mai yawa ƙasa da shi fiye da tushe abu. Tare da kadan dumama ko haske yawanci warware electrons da sunadaran da kazamta semiconductors. Sanya bar zarra daukan wani electron rami. Amma da electron rami recombination ba faru. bayarwa rami watsin ne negligible. Wannan shi ne saboda a kananan adadin najasa kwayoyin halitta ba da damar free electrons sau da yawa kusa da rami, kuma a rike shi. Electrons ne wasu ramuka, amma ba su iya cika su saboda kasa da makamashi matakin.

A kadan ƙari bayarwa najasa dama umarni qara yawan madugu electrons a kwatanta da yawan free electrons a cikin muhimmi semiconductor. Electrons nan - da babban dako na atomic zargin najasa semiconductors. Wadannan abubuwa ne da mulkin ga n-type semiconductors.

Impurities cewa daura electrons da semiconductor, kara yawan ramukan da shi, da ake kira Mai karɓar. Mai karɓar impurities ne sinadaran abubuwa da karami yawan electrons a valence matakin fiye da tushe daga cikin semiconductor. Boron, gallium, indium - Mai karɓar najasa a silicon.

A halaye na semiconductor ne dogara a kan ta crystal tsarin lahani. Wannan sa wajibcin girma musamman m lu'ulu'u. Da sigogi na semiconductor madugu sarrafawa da Bugu da kari na dopants. Silicon lu'ulu'u doped da phosphorus (V subgroup kashi) wanda shi ne mai bayarwa don ƙirƙirar crystal silicon n-type. Domin crystal tare da wani p-type silicon gudanar boron Mai karɓar. Semiconductors cika Fermi matakin ya motsa shi zuwa ga tsakiyar band rata halitta a cikin wannan hanya.

single-kashi semiconductors

Mafi na kowa semiconductor ne, ba shakka, silicon. Tare da Jamus, ya kasance cikin samfur na babban aji na semiconductors da cewa suna da irin wannan crystal Tsarin.

Structure crystal Si da Ge ne guda a matsayin cewa na lu'u-lu'u da kuma α-tin. Yana kewaye kowane zarra 4 mafi kusa kwayoyin halitta wanda ya samar da wani tetrahedron. Irin wannan daidaituwa da aka kira sau hudu. Lu'ulu'u tetradricheskoy bond karfe tushe don lantarki a masana'antu da kuma taka muhimmiyar rawa a hanyoyin sadarwa na zamani. Wasu daga cikin abubuwa V kuma VI na lokaci-lokaci tebur kungiyar ne ma semiconductors. Misalai na irin wannan semiconductors - phosphorus (P), sulfur (S), selenium (Se), kuma tellurium (Te). Wadannan semiconductors iya zama sau uku kwayoyin halitta (P), disubstituted (S, Se, Te) ko wani hudu-Musulunci daidaituwa. A sakamakon irin wannan abubuwa iya zama a dama daban-daban crystalline Tsarin, kuma shi ma za a shirya a cikin nau'i na gilashi. Alal misali, Se girma a monoclinic da trigonal crystal Tsarin ko matsayin taga (wanda kuma za a iya daukarsa a matsayin polymer).

- Diamond yana da kyau kwarai thermal watsin, mãdalla da inji kuma Tantancewar Properties, high inji ƙarfi. Da nisa daga samar da makamashi rata - De = 5,47 EV.

- Silicon - semiconductor amfani da hasken rana Kwayoyin, kuma amorphous form, - a wani bakin ciki-film hasken rana Kwayoyin. Shi ne mafi amfani a semiconductor hasken rana Kwayoyin, sauki tsirar, yana da kyau lantarki da kuma na inji Properties. De = 1,12 EV.

- Germanium - semiconductor amfani a cikin gamma-ray spectroscopy, high yi hasken rana Kwayoyin. Amfani a cikin na farko diodes da transistors. Yana bukatar kasa tsaftacewa fiye da silicon. De = 0,67 EV.

- selenium - a semiconductor, wanda aka yi amfani a cikin selenium rectifiers ciwon high radiation juriya da kuma ikon warkar da kanta.

Biyu-kashi mahadi

Properties na Semiconductors kafa abubuwa 3 da 4 na lokaci-lokaci tebur kungiyoyin kama da kaddarorin mahadi 4 kungiyoyin. A mi} a mulki daga 4 kungiyoyin na abubuwa to tana gina 3-4 gr. Yana sa sadarwar jera domin ionic cajin kai electrons daga zarra zuwa Atom 3 Group 4 Group. Ionicity canjãwa da kaddarorin semiconductors. Ana sa da karuwa a cikin Coulomb makamashi da kuma ion-ion hulda makamashi rata electron band tsarin. MISALI binary mahadi daga irin wannan - indium antimonide, InSb, gallium arsenide GaAs, gallium antimonide GaSb, indium phosphide InP, aluminum antimonide AlSb, gallium phosphide rata.

Ionicity ƙaruwa da kuma muhimmancinsa tsiro mafi kungiyoyin a mahadi 2-6 mahadi, kamar cadmium selenide, tutiya sulfide, cadmium sulfide, cadmium Telluride, tutiya selenide. A sakamakon haka, mafi yawan mahadi 2-6 kungiyoyin haramta band fadi fiye da 1 maddî, fãce Mercury mahadi. Mercury Telluride - ba tare da samar da makamashi rata semiconductor, Semi-karfe, kamar α-tin.

Semiconductors 2-6 kungiyoyin da ya fi girma makamashi rata find amfani a samar da lasers da nuni. Binary kungiyoyin 6 2- fili tare da wani ƙunci ta rata makamashi dace da infrared karba. Binary mahadi daga abubuwa na kungiyoyin 1-7 (cuprous bromide CuBr, AgI azurfa iodide, jan chloride CuCl) saboda da high ionicity da fadi bandgap W maddî. Sun yi ba a zahiri semiconductors, kuma insulators. Crystal girma kugìyàr makamashi saboda Coulomb interionic hulda facilitates structuring atoms gishiri da shida domin, a maimakon na quadratic daidaita. Mahadi 4-6 kungiyoyin - sulfide, gubar Telluride, tin sulfide - kamar yadda semiconductors. Ionicity daga cikin wadannan abubuwa ma na inganta da samuwar sixfold daidaituwa. Yawa ionicity ba hana gaban da suke da wata sosai kunkuntar band gibba, su za a iya amfani da shi don samun infrared radiation. Gallium nitride - a fili kungiyoyin 3-5 da fadi da makamashi rata, sami aikace-aikace a semiconductor lasers da haske-emitting diodes aiki a blue ɓangare na bakan.

- GaAs, gallium arsenide - a kan bukatar bayan na biyu silicon semiconductor ne fiye da amfani da wani substrate ga sauran conductors, misali, GaInNAs da InGaAs, a setodiodah infrared, high mita transistors da ICs, inganci sosai hasken rana Kwayoyin, Laser diodes, gane nukiliya magani. De = 1,43 EV, wanda inganta ikon na'urorin kamar yadda idan aka kwatanta da silicon. Gaggautsa, ya ƙunshi mafi impurities wuya zuwa tsirar.

- ZnS, tutiya sulfide - tutiya gishiri na hydrogen sulphide tare da haramta band zones da kuma 3,54 3,91 EV, amfani da lasers da kuma matsayin phosphor.

- SnS, tin sulfide - semiconductor amfani a photoresistors da photodiodes, de = 1,3 da kuma 10 maddî.

oxides

Da karfe oxides zai fi dacewa ne m insulators, amma akwai ban. Misalai na irin wannan semiconductors - nickel oxide, jan oxide, cobalt oxide, jan dioxide, da baƙin ƙarfe oxide, europium oxide, tutiya oxide. Tun da jan dioxide wanzu a matsayin ma'adinai cuprite, da kaddarorin da aka yi karatu maida. A hanya ga namo da irin wannan semiconductor ne ba tukuna gaba ɗaya bayyana, don haka su yi amfani da shi ne har yanzu iyaka. An togiya ne tutiya oxide (ZnO), fili kungiyoyin 2-6, da ake amfani da matsayin transducer da kuma a samar da m kaset da kuma filastocin.

A halin da ake ciki canja da cika fuska bayan jejjerawa aka gano a cikin da yawa mahadi na jan karfe tare da oxygen. A farko high zazzabi superconductor bude Bednorz da Muller, aka fili semiconductor dangane La ₂ CuO _4, da makamashi rata na 2 maddî. Musanya divalent trivalent lanthanum, barium ko strontium, ya gabatar a cikin semiconductor cajin yan dako na ramukan. Samar da zama dole rami taro sa La ₂ CuO ₄ superconductor. A wannan lokaci, da mafi yawan zafin jiki na miƙa mulki ga superconducting jihar ne da karin HgBaCa ₂ Cu ₃ Ya _8. A high matsa lamba, da darajar ne 134 K.

ZnO, tutiya oxide varistor da ake amfani, blue haske-emitting diodes, gas na'urori masu auna sigina, nazarin halittu masu auna sigina, coatings windows zuwa yin tunãni infrared haske, kamar yadda wani shugaba a LCD nuni da hasken rana batura. De = 3,37 EV.

mai lebur lu'ulu'u

Biyu mahadi kamar diiodide gubar, gallium selenide da molybdenum disulphide bambanta, hanyõyi crystal tsarin. A yadudduka ne covalent shaidu na babba ƙarfi, yawa da karfi fiye da van der Waals shaidu tsakanin yadudduka da kansu. Semiconductors irin nau'in ne ban sha'awa saboda electrons nuna hali a cikin yadudduka a kusan-biyu-girma. Hulda da yadudduka da aka canza ta hanyar gabatar waje atoms - intercalation.

MoS _2, molybdenum disulfide da ake amfani a high mita gane, rectifiers, memristor, transistors. De = 1,23 da kuma 1.8 maddî.

kwayoyin semiconductors

Misalan semiconductors kan hanyoyin gudanar da mahadi - naphthalene, polyacetylene (CH _{2) n,} anthracene, polydiacetylene, ftalotsianidy, polyvinylcarbazole. Organic semiconductors da wani amfani a kan wadanda ba kwayoyin: suna da sauki don goya da ake so quality. Abubuwa da conjugate shaidu samar -C = C-C = mallaka gwaji Tantancewar ba linearity kuma, saboda wannan, a optoelectronics amfani. Bugu da ƙari, da samar da makamashi band rata kwayoyin semiconductor fili na dabara bambanta canji cewa sauƙin fiye da na al'ada semiconductors. Crystalline allotropes na carbon fullerenes, Graphene, nanotubes - kuma semiconductors.

- Fullerene yana da wani tsarin a cikin nau'i na rufaffiyar convex polyhedron ugleoroda ko da yawan kwayoyin halitta. A doping fullerene C ₆₀ da wani Alkali karfe canza shi a cikin wani superconductor.

- graphite carbon monoatomic Layer aka kafa, an haɗa a wani biyu-girma kyakkyawan raga. Record yana da watsin da electron motsi, high rigidity

- Nanotubes an yi birgima cikin wani bututu graphite farantin da ciwon diamita na dama nanometers. Wadannan siffofin na carbon da babban alkawari a nanoelectronics. Dangane da hada guda biyu na iya zama ƙarfe ko semiconductor quality.

Magnetic semiconductors

Mahadi da Magnetic ions na europium da manganese da m Magnetic da semiconducting Properties. Misalai na irin wannan semiconductors - europium sulfide, selenide europium da kuma m mafita, wannan CD _1-x mn _x Te. Da abun ciki na Magnetic ions rinjayar biyu abubuwa nuna Magnetic Properties kamar ferromagnetism da antiferromagnetism. Semimagnetic semiconductors - shi ne mai wuya Magnetic semiconductors mafita wadda dauke da Magnetic ions a low taro. Irin m mafita jawo hankalin hankalin ka hange da kuma babban m na yiwu aikace-aikace. Alal misali, a bambanci ga wadanda ba Magnetic semiconductors, ba za su iya isa wani sau miliyan ya fi girma Faraday juyawa.

Strong magnetooptical effects na Magnetic semiconductors damar su yi amfani da ga Tantancewar daidaitowa. Perovskites, kamar mn _0,7 Ca _0,3 Yã _3, da kaddarorin ne mafĩfĩta karfe-semiconductor mika mulki, wanda kai tsaye dogara a kan Magnetic filin sakamakon a sabon abu na giant magneto-resistivity. Suna amfani da rediyo, Tantancewar na'urorin, wanda ake sarrafawa da wani Magnetic filin, a obin na lantarki waveguide na'urorin.

semiconductor ferroelectrics

Wannan irin lu'ulu'u ne halin da kasancewar a cikin su da wutar lantarki lokacin da ya faru na maras wata-wata rabuwa. Alal misali, irin kaddarorin ne semiconductors kai titanate PbTiO _3, barium titanate BaTiO _3, germanium Telluride, GeTe, tin Telluride SnTe, wanda a low yanayin zafi da ferroelectric Properties. Wadannan kayan ana amfani da maras mike Tantancewar, piezoelectric na'urori masu auna sigina da ƙwaƙwalwar na'urorin.

A iri-iri na semiconductor kayan

Bugu da kari ga semiconductor kayan da aka ambata a sama, akwai wasu da dama da ba su fada karkashin daya daga wadannan iri. Mahadi dabara 1-3-5 abubuwa ₂ (AgGaS ₂₎ kuma 2-4-5 ₂ (ZnSiP ₂₎ samar da wata chalcopyrite crystal tsarin. Saduwa da tetrahedral mahadi analogous semiconductors 3-5 da kuma 2-6 kungiyoyin da tutiya blende crystal tsarin. Mahadi wanda ya samar da semiconductor abubuwa 5 da 6 kungiyoyin (similar to As ₂ Se _3), - da semiconductor a cikin nau'i na crystal ko gilashi. Chalcogenides na bismuth da antimony ake amfani a semiconductor thermoelectric janareto. The kaddarorin da irin wannan semiconductor ne musamman mai ban sha'awa, amma ba su sami shahararsa saboda da iyaka aikace-aikace. Duk da haka, da cewa sun wanzu, ya tabbatar da kasancewar ba tukuna cikakken bincika filin na semiconductor kimiyyar lissafi.