Izendlalelo ze-epitaxial ziwasiza kanjani amadivayisi we-semiconductor?

Umsuka wegama elithi epitaxial wafer

Okokuqala, ake sandise umqondo omncane: ukulungiswa kwe-wafer kufaka izixhumanisi ezimbili ezinkulu: ukulungiswa kwe-substrate kanye nenqubo ye-epitaxial. I-substrate iyicwecwe elenziwe nge-semiconductor single crystal material. I-substrate ingangena ngokuqondile kunqubo yokukhiqiza i-wafer ukuze ikhiqize amadivaysi e-semiconductor, noma ingacutshungulwa ngezinqubo ze-epitaxial ukukhiqiza ama-epitaxial wafers. I-Epitaxy isho inqubo yokukhulisa ungqimba olusha lwekristalu eyodwa ku-substrate yekristalu eyodwa ecutshungulwe ngokucophelela ngokusika, ukugaya, ukupholishwa, njll. Ikristalu entsha eyodwa ingaba yinto efanayo ne-substrate, noma ingaba izinto ezahlukene (homogeneous) epitaxy noma heteroepitaxy). Ngenxa yokuthi ungqimba olusha lwekristalu olulodwa lunwebeka futhi lukhule ngokwesigaba sekristalu se-substrate, lubizwa ngokuthi ungqimba lwe-epitaxial (ugqinsi luvamise ukuba ama-microns ambalwa, kuthatha i-silicon njengesibonelo: incazelo yokukhula kwe-silicon epitaxial iku-silicon single. I-crystal substrate enomumo othile wekristalu Ungqimba lwekristalu olunobuqotho besakhiwo se-lattice kanye nokuqina okuhlukile nokujiya okune-crystal orientation efanayo njengoba i-substrate ikhuliswa. i-substrate ene-epitaxial layer ibizwa ngokuthi i-epitaxial wafer (i-epitaxial wafer = i-epitaxial layer + substrate). Uma idivayisi yenziwa kungqimba lwe-epitaxial, ibizwa ngokuthi i-positive epitaxy. Uma idivayisi yenziwe ku-substrate, ibizwa ngokuthi i-reverse epitaxy. Ngalesi sikhathi, ungqimba lwe-epitaxial ludlala indima yokusekela kuphela.

Isicwecwana esicwebezelayo

Izindlela zokukhula ze-Epitaxial

I-Molecular beam epitaxy (MBE): Iwubuchwepheshe bokukhula kwe-semiconductor epitaxial okwenziwa ngaphansi kwezimo ze-vacuum eziphezulu kakhulu. Kule nqubo, izinto eziwumthombo ziyahwamuka ngendlela ye-athomu noma ama-molecule bese zifakwa ku-crystalline substrate. I-MBE iwubuchwepheshe obunembe kakhulu futhi obulawulekayo bokukhula kwefilimu encane ye-semiconductor engalawula ngokunembile ukushuba kwezinto ezifakiwe ezingeni le-athomu.
I-Metal organic CVD (MOCVD): Enqubweni ye-MOCVD, i-organic metal ne-hydride gas N gas equkethe izakhi ezidingekayo inikezwa ku-substrate ngezinga lokushisa elifanele, ibhekana nokusabela kwamakhemikhali ukuze kukhiqizwe impahla edingekayo ye-semiconductor, futhi ifakwa ku-substrate. kuvuliwe, kuyilapho izinhlanganisela ezisele kanye nemikhiqizo yokusabela kukhishwa.
I-Vapor phase epitaxy (VPE): I-Vapor phase epitaxy iwubuchwepheshe obubalulekile obuvame ukusetshenziswa ekukhiqizeni amadivaysi e-semiconductor. Umgomo oyisisekelo uwukuthutha umhwamuko wezinto eziyisisekelo noma izinhlanganisela kugesi yenkampani yenethiwekhi, nokufaka amakristalu ku-substrate ngokusabela kwamakhemikhali.

Yiziphi izinkinga ezixazululwa yinqubo ye-epitaxy?

Izinto zekristalu eyodwa kuphela azikwazi ukuhlangabezana nezidingo ezikhulayo zokukhiqiza amadivaysi e-semiconductor ahlukahlukene. Ngakho-ke, ukukhula kwe-epitaxial, ubuchwepheshe obuncane bokukhula kwe-crystal eyodwa, kwathuthukiswa ekupheleni kuka-1959. Ngakho-ke yimuphi umnikelo othize ubuchwepheshe be-epitaxy ekuthuthukisweni kwezinto?

Ku-silicon, lapho ubuchwepheshe bokukhula kwe-silicon epitaxial buqala, kwakuyisikhathi esinzima ngempela sokukhiqizwa kwe-silicon high-frequency kanye nama-transistors anamandla aphezulu. Ngokombono wezimiso ze-transistor, ukuze uthole imvamisa ephezulu namandla aphezulu, i-voltage yokuwohloka yendawo yokuqoqa kufanele ibe phezulu futhi ukumelana nochungechunge kufanele kube kuncane, okungukuthi, ukwehla kwe-saturation voltage kumele kube kuncane. Okwangaphambili kudinga ukuthi ukumelana kwezinto endaweni yokuqoqa kufanele kube phezulu, kuyilapho lokhu kugcina kudinga ukuthi ukumelana kwezinto endaweni yokuqoqa kufanele kube phansi. Lezi zifundazwe ezimbili ziyaphikisana. Uma ubukhulu bezinto endaweni yokuqoqa buncishiswa ukuze kuncishiswe ukumelana nochungechunge, i-silicon wafer izoba mncane kakhulu futhi ibe ntekenteke ukuthi ingacutshungulwa. Uma ukumelana kwempahla kuncishisiwe, kuzophikisana nemfuneko yokuqala. Nokho, ukuthuthukiswa kobuchwepheshe be-epitaxial kuye kwaphumelela. buxazulule lobu bunzima.

Isixazululo: Khulisa ungqimba oluqinile lwe-epitaxial ku-substrate emelana kancane kakhulu, bese wenza idivayisi kungqimba lwe-epitaxial. Lesi singqimba se-epitaxial esiphezulu siqinisekisa ukuthi i-tube ine-voltage ephezulu yokuphuka, kuyilapho i-substrate ephansi yokumelana nayo inciphisa ukumelana kwe-substrate, ngaleyo ndlela inciphisa ukwehla kwe-saturation voltage, ngaleyo ndlela ixazulule ukuphikisana phakathi kokubili.

Ngaphezu kwalokho, ubuchwepheshe be-epitaxy obufana ne-vapor phase epitaxy kanye ne-liquid phase epitaxy ye-GaAs nezinye i-III-V, II-VI nezinye izinto zokwakha ze-molecular compound semiconductor nazo ziye zathuthukiswa kakhulu futhi zaba yisisekelo samadivayisi amaningi we-microwave, amadivaysi e-optoelectronic, amandla. Kuwubuchwepheshe benqubo ebaluleke kakhulu ekukhiqizeni amadivaysi, ikakhulukazi ukusetshenziswa ngempumelelo kwe-molecular beam kanye ne-metal organic vapor phase epitaxy technology ezingxenyeni ezincane, ama-superlattice, imithombo ye-quantum, ama-superlattice ahluziwe, kanye ne-epitaxy yeleveli encane ye-athomu, okuyisinyathelo esisha ocwaningweni lwe-semiconductor. Ukuthuthukiswa "kobunjiniyela bebhande lamandla" emkhakheni kuye kwabeka isisekelo esiqinile.

Kuzinhlelo zokusebenza ezisebenzayo, amadivaysi e-bandgap semiconductor abanzi ahlala enziwa kungqimba lwe-epitaxial, futhi i-silicon carbide wafer ngokwayo isebenza njenge-substrate. Ngakho-ke, ukulawulwa kongqimba lwe-epitaxial kuyingxenye ebalulekile yemboni ye-bandgap semiconductor ebanzi.

Amakhono angu-7 amakhulu kubuchwepheshe be-epitaxy

1. Izingqimba ze-epitaxial eziphakeme (eziphansi) zingakhuliswa nge-epitaxially kuma-substrates aphansi (aphezulu) okumelana.
2. Ungqimba lwe-epitaxial lohlobo lwe-N (P) lungakhuliswa nge-epitaxially ku-substrate yohlobo lwe-P (N) ukuze kwakhe ukuhlangana kwe-PN ngokuqondile. Ayikho inkinga yesinxephezelo uma usebenzisa indlela yokusabalalisa ukwenza ukuhlangana kwe-PN ku-crystal substrate eyodwa.
3. Kuhlanganiswe nobuchwepheshe be-mask, ukukhula kwe-epitaxial okukhethiwe kwenziwa ezindaweni ezikhethiwe, ukudala izimo zokukhiqizwa kwamasekethe ahlanganisiwe namadivayisi anezakhiwo ezikhethekile.
4. Uhlobo nokugxila kwe-doping kungashintshwa ngokuvumelana nezidingo ngesikhathi senqubo yokukhula kwe-epitaxial. Ukushintsha kokugxilisa ingqondo kungase kube ushintsho kungazelelwe noma ushintsho olunensayo.
5. Ingakhula inhlanganisela ehlukahlukene, enezendlalelo eziningi, enezingxenye eziningi kanye nezingqimba ezincane kakhulu ezinezingxenye eziguquguqukayo.
6. Ukukhula kwe-Epitaxial kungenziwa ezingeni lokushisa eliphansi kunephuzu lokuncibilika lezinto ezibonakalayo, izinga lokukhula liyalawuleka, futhi ukukhula kwe-epitaxial kogqinsi lwezinga le-athomu kungafinyelelwa.
7. Ingakhula izinto ze-crystal eyodwa ezingakwazi ukudonswa, njenge-GaN, izendlalelo zekristalu eyodwa yamakhompiyutha e-tertiary kanye ne-quaternary, njll.