Kutheni i-High-Purity Graphite ibaluleke kakhulu kwi-SiC Epitaxy Defect Control

Umgangatho we-wafer ye-silicon carbide (SiC) eveliswayo uphenjelelwa lutshintsho oluncinci kwindawo yokukhula. Indawo abantu abaninzi abangayicingiyo yi-graphite egqume i-reactor. Imela uvavanyo lobushushu obukhulu obufumaneka ngaphakathi kwi-reactor ngelixa ixhasa kwaye ibeka i-wafer ngexesha le-epitaxy. Ukuba i-graphite ayicocekanga okanye yakhiwe ngendlela engaqhelekanga, iinxalenye ezincinci zezinto okanye impendulo engafunekiyo zinokubekwa kuyo yonke inkqubo yokukhula. Iingxaki ezincinci kumphezulu we-graphite zinokuqhakaza zibe ziziphene ezinkulu ze-wafer, nto leyo ekhokelela kumsebenzi omninzi kunye nemveliso ephantsi kubavelisi bee-chip. Ngoko ke imeko kunye nokucoceka kwe- I-Graphite susceptor yingxaki ebaluleke ngakumbi kunokuba uninzi lunokucinga.

Indlela iGraphite Purity echaphazela ngayo imiba yeenxalenye kwiEpitaxy Chambers?

Iiparticles zizinto ezibangela i-wafer exhaphakileyo kwiigumbi ze-SiC epitaxy, kwaye zihlala zibandakanya i-graphite kule nkqubo. Iinxalenye ze-graphite zihlala kwindawo eshushu ye-reactor ye-SiC, zithwala i-wafer kwaye zichaphazela imiphetho yobushushu. Ngokusebenzisa i-graphite engacocekanga kangako, ukungcola okuncinci, okufana nokungcola kwesinyithi, uthuthu, okanye iintsalela ezisele zenkqubo, zinokuphuma igesi kwi-graphite kancinci ngokuhamba kwexesha ngexesha lokukhula kobushushu obuphezulu. Ukungcola okuphuma kwi-gass kuhlala kungabonakali kwigumbi, kodwa ekugqibeleni kuwela kumphezulu we-wafer, okanye kube yinxalenye yesigaba segesi. Umzekelo, kwenye i-application, i-fab yakhetha i-graphite yomgangatho ophantsi ukuze kongiwe iindleko. Nangona kungekho ngxaki ibonakalayo ngexesha elifutshane ekuqaleni, emva kwemijikelo emininzi ye Sic epitaxy , kwabonwa imingxunya engaqhelekanga kunye namabala arhabaxa kumphezulu we-wafer. Umthombo weziphene ezinjalo wawulandelwa zii-micro particles ezikhutshwa kwi-graphite holder okanye i-susceptor. Ezi ncinci zazingena kwigumbi lokukhula kwaye zisebenze njengembewu ngendlela engathandekiyo. Ubuninzi obungalinganiyo benxalenye ye-graphite buya kuba negalelo ekuqhekekeni kwe-micro-surface kumphezulu wenxalenye xa kufudunyezwa, okukhokelela ekuchithekeni kwee-small particles kwigumbi ngokuhamba kwexesha, nangona inxalenye ingabonakala icocekile. Ke ngoko, ukujonga umthombo we-graphite kunye nembali yayo ngumsebenzi oqhelekileyo kwii-fabs ukuze kuthintelwe iziphene ezinxulumene nee-particles. I-graphite ecocekileyo kakhulu enomlinganiselo wothuthu olawulwayo idla ngokunqweneleka, ngakumbi kwimveliso yexesha elide. Inani lemijikelo yobushushu yeenxalenye nayo ijongwa njengoko izinto ziya kuchitha ii-small nasemva kokulungiswa okuhle kokuqala. Kwakhona, indlela yokulungisa iinxalenye ze-graphite ichaphazela iziphene. Umzekelo, iinkqubo zokucoca ngamandla ziya konakalisa umphezulu we-graphite kwaye zibangele ii-micro-cracks. Indlela ekhethwayo yinkqubo yokucoca ethambileyo, elawulwayo enonxibelelwano oluncinci lomzimba kunye neenxalenye ze-graphite. Ngenxa yezizathu zoqoqosho, ukutshintsha iindawo ngokukhawuleza kunokuba bekulindelwe kunokuba ngcono kunokujongana nokulahleka kwesivuno kumanqanaba alandelayo. Ngamafutshane, ulawulo lokuveliswa kwamasuntswana kwinkqubo eqhelekileyo ye-SiC epitaxy lujikeleza kwiinkcukacha ezincinci kumgangatho wezinto kunye neendlela zokuphatha. Umba womgangatho wegrafiti uphambili kulo mba.

Iimfuneko zezinto eziphathekayo zeenxalenye ze-High-End SiC Epitaxial kunye neeSusceptors

Kwi-SiC epitaxy, iindawo ezikwi-reactor azipheleli nje ekubeni 'zibambe' i-wafer. Ii-Susceptors, ii-graphite carriers kunye nee-hotzone components kwi-reactor zichaphazela ngokuthe ngqo ukukhula kwekristale. Yingakho izixhobo zifuna kakhulu kwaye isiphene esincinci siya kubonakala njengesiphene kwi-wafer. Uzinzo oluphezulu lobushushu luyimfuneko esisiseko. Ezi ndawo zifudunyezwa kumaqondo obushushu aphezulu kakhulu ixesha elide (ngamanye amaxesha imijikelo yokufudumeza/yokupholisa ephindaphindayo). Izinto ezingenakugcina uzinzo kwezi qondo lobushushu ziya kujika kwaye ekugqibeleni zinokuqhekeka. Utshintsho oluncinci kwi-geometry lunokutshintsha kakhulu ukuhamba kwegesi kunye nokusasazwa kobushushu okubangela ukukhula kwekristale engalinganiyo kumphezulu we-wafer. Ubunyulu yenye into ebalulekileyo. Iinkqubo ze-SiC eziphezulu zifuna umxholo wesinyithi ophantsi kakhulu kunye nenqanaba eliphantsi kakhulu lothuthu kwiindawo ezisekelwe kwi-graphite. Ngexesha lokusebenza, ii-trace metals ziya kuphuma kancinci kwiindawo, ukungcola kunokusasaza kwigumbi kwaye kubangele ukungcola kwamasuntswana okanye iziphene zekristale zasekuhlaleni. Kwezinye izinto, i-random stacking fault ilandelwe yiqela elinye le-susceptor engcolileyo. Ulwakhiwo lomphezulu luyimfuneko ebalulekileyo. Umphezulu ogudileyo nolinganayo uya kunceda ekunciphiseni ukuchitheka kwamasuntswana ngexesha lomjikelo wokufudumeza/wokupholisa. Umphezulu ongalinganiyo, okanye iimbobo ngaphakathi kwesakhiwo somphezulu, uya kuqhubeka uqhekeka ngexesha lokusebenza kwaye ngaloo ndlela uvelise umthombo ozinzileyo wamasuntswana kwigumbi. Umgangatho wokugquma ungomnye wemfuno ebalulekileyo. Ii-susceptors ezininzi eziphezulu zisebenzisa i-SiC coating njengomaleko wokukhusela. I-coating kufuneka inamathele kakuhle kwizinto ezisisiseko kwaye kufuneka imelane nokusebenza ixesha elide. Ukubopha okungalunganga kunye nokususwa kwe-lamination kuya kuveza ngokuthe ngqo i-base graphite kwindawo yokusabela enzima. Sihlala sibona oku kwizicelo zokwenyani: umzekelo, i-wafer fab esebenza ixesha elide yemveliso iya kubona ukuba izinga lesiphene linyuka ngokuthe chu emva kwamakhulu ee-cycles. Ukuhlola i-susceptor kuya kubonisa ukuguguleka okuncinci kwe-coating kunye nokukhukuliseka komphetho. Ukutshintsha okanye ukutshintsha i-component kuya kubuyisela izinga lesiphene kwinqanaba elamkelekileyo. Ukukhetha izixhobo ezifanelekileyo akupheleli nje ekusebenzeni kokuqala kwezixhobo, kodwa kukuzinza kwezinto kwimijikelo ephindaphindwayo.

Imiphumo yoLwakhiwo lweeNkozo kuZinzo loBushushu kwiinkqubo ze-AIXTRON G10

Ulwakhiwo lweenkozo zezinto zegrafiti ngaphakathi kweSiC enobushushu obuphezulu Ukukhula kwe-Epitaxy Inkqubo, efana ne-AIXTRON G10, inefuthe elikhulu ekuzinzeni kobushushu. Oku kunxulumene notshintsho lobukhulu, ukugcinwa kwesimo, kunye nempendulo kwi-thermal cycle. I-Graphite ayisiyonto eqinileyo. Iqulathe iikristali ezininzi okanye iinkozo. Iikristali nganye inokuba neendlela ezahlukeneyo. Xa kukho ulawulo olubi lobukhulu bengqolowa ngaphakathi kwe-graphite component, kuvela ukusasazwa kobushushu okungalinganiyo. Iindawo zenxalenye ziyafudumala kwaye ziphole ngamanani ahlukeneyo. Oku kudala uxinzelelo lwangaphakathi kwinqanaba elincinci. Kancinci kancinci ngokuhamba kwexesha olu xinzelelo lwangaphakathi lubangela ukugoba okanye ukuphambuka kwiindawo ezifana ne-susceptor okanye i-wafer carrier. Le nkqubo ibonakala ngokulula ngexesha lokuveliswa. Ihlala ibonakala xa umgca we-wafer usebenza kumaqondo obushushu aphezulu. Umgangatho we-wafer uqala ukushukuma emva kwamakhulu emijikelo yobushushu. Utshintsho kubukhulu luyanda, kwaye iziphene zomphetho ziqala ukuvela rhoqo. Nje ukuba ezi ndawo zihlolwe zihlala zineempawu zokugoba okanye ukudinwa kwezinto. Izakhiwo zengqolowa ezintle ezinokusasazwa kwekristali ezilawulwayo ziya kuba nokuzinza okungcono kobushushu kuneenkozo ezirhabaxa okanye izakhiwo ezingacwangciswanga. Oku kuya kubangela ukudluliselwa kobushushu okulinganayo kunye nokunciphisa amanqaku oxinzelelo lwendawo. Xa i-grain structure ifanelekile, la malungu aya kuxhathisa ukugoba nokuba kuqengqeleka amakhulu emijikelo yobushushu. Izakhiwo ezirhabaxa okanye izakhiwo ze-grain ezingasasazwanga kakuhle zibangela iindawo ezibuthathaka ngaphakathi kwenxalenye, nto leyo evumela ukuqhekeka okuncinci kunye nokukhululwa kwamasuntswana kwigumbi. Omnye umba obalulekileyo ekufuneka uqwalaselwe kukuxhathisa ukutshiswa kobushushu. Kukho iindawo apho inxalenye itshintsha khona ubushushu obukhulu njengokulayisha kwi-reactor okanye xa isuswa. Ukuba kukho imida ebuthathaka phakathi kwee-grain, ii-micro-cracks zinokwenzeka ecaleni kwemigca yee-grain. Nangona oku kungabangela ukusilela kwenxalenye, kuvumela obu buthathaka ukuba bube kwisixhobo, nto leyo ekhokelela kwimiba yokuthembeka kwixesha elizayo. Uninzi lwee-fabs lulandela ubomi benxalenye nganye ngeeyure ezisetyenzisiweyo, kunye nenani lemijikelo yobushushu kunye nonyango lobushushu olupheleleyo. La malungu anesakhiwo se-grain structure esilungisiweyo kakuhle anobomi obude, iziphumo ezihambelanayo ngokuhamba kwexesha.

Ukunciphisa Ungcoliseko lweMetallic kwi-High-Purity Graphite Components

Enye yeengxaki "ezingabonakaliyo" kodwa ezibalulekileyo kuyo nayiphi na inxalenye yegrafiti, kuquka nenkqubo ye-SiC epitaxy, kukungcola kwesinyithi. Nokuba zincinci iintsimbi ezikwinxalenye yegrafiti zinokungena kwinkqubo kwaye zibe ngumthombo wobunzima bokulandelela iziphene kwi-reactor ye-SiC epitaxy njenge-AIXTRON G10. Ezi zinyithi zihlala zivela kwizinto eziluhlaza okanye amanyathelo ahlukeneyo okucubungula abandakanyekayo ekwenziweni kwenxalenye yegrafiti. Izinto ezifana ne-Iron, i-Nickel, i-Calcium kunye ne-Sodium ziqhelekile kwaye zihlala zibambeke kwi-graphite eninzi kubushushu begumbi, nangona kunjalo, kubushushu obuphezulu benkqubo esetyenziswa kwi-SiC epitaxy, ezi zinto zisenokuhamba. Ezi zinyithi zincinci ekugqibeleni zinokuphuma kwigesi okanye zifudukele kumphezulu ngexesha lokujikeleza okuphindaphindiweyo kokufudumala/ukupholisa kwindawo eshushu, oko kukuthi i-susceptor okanye i-wafer carrier ngokwayo. Imeko eqhelekileyo ingaba ngolu hlobo: i-fab iqala iqela lemveliso isebenzisa iindawo ezintsha zegrafiti. Ii-wafer ezimbalwa zokuqala zilungile kwaye azibonisi ziphene, kodwa emva kwexesha elithile, iziphene ezincinci ziqala ukubonakala. Zihlala ziyimingxuma emincinci, iimpazamo ze-random stack, okanye iziganeko ze-particle ezingachazekiyo. Kulula ukurhanela ngokungafanelekanga ukuhamba kwegesi okanye isiganeko sokungcola ngexesha lokucoca igumbi. Kodwa uhlalutyo oluneenkcukacha ludla ngokukhokelela ekukhutshweni kancinci kweentsimbi ezilandelelanayo ezivela kwi-graphite components. Ukulawula ubunyulu be-graphite yenye yezona zinto zibalulekileyo. Kwizinto ezibalulekileyo, i-graphite ecociweyo kubushushu obuphezulu enomxholo womlotha ophantsi ihlala ikhethwa. Eli nyathelo lokucoca lisusa uninzi lweentsalela zesinyithi. I-graphite enjalo inokugcina izinto zivalelekile ixesha elide naphantsi kwemijikelo yokufudumeza/yokupholisa ephindaphindwayo. Ukuhlolwa okungenayo kweendawo ze-graphite nako kubaluleke kakhulu kwezinye izinto. Ukuvavanya ii-graphite batches ngeendlela ezifana ne-ICP-OES okanye i-XRF kunokuthintela ukusebenzisa iindawo ezingcolisiweyo. Kunokuthintela nokuxuba iindawo ezivela kwimithombo eyahlukeneyo ngaphakathi kokuhamba kwenkqubo efanayo. Ii-coatings ezifana ne-SiC okanye i-TaC nazo zinceda ukusombulula ingxaki ngokusebenza njengomqobo phakathi kwenxalenye ye-graphite kunye nendawo yenkqubo. Ukuba nje i-coating ibekwe kakuhle kwaye ibotshelelwe kwi-graphite substrate engaphantsi, kuya kunciphisa ukusebenzisana kwenxalenye ye-graphite nendawo yenkqubo. Okokugqibela kodwa okungabalulekanga kukuphathwa nokugcinwa kwenxalenye ye-graphite. Iinxalenye ze-graphite zinokungcoliswa ngexesha lokuphathwa ngeeglavu ezingcolileyo, izixhobo okanye ngokugcinwa kwishelufu engcolileyo. Olu ngcoliso lomphezulu lungangena kwisithando ngexesha lomjikelo wokufudumala. Ukunciphisa ungcoliso lwesinyithi lweendawo ze-graphite, yimizamo emininzi emincinci. Kufuneka izinto ezicocekileyo kakhulu kunye nokuziqhelanisa kakuhle nolawulo oluqinileyo lwenkqubo.

Kutheni iiNkqubo zeVeeco EPIK Zifuna Izixhobo zeGraphite eziPhantsi kakhulu?

Iindawo zegrafiti ngaphakathi kweqonga leVeeco EPIK Systems zidlula kwenye yezona meko zinzima kakhulu kwimveliso ye-semiconductor. Ezi nxalenye zijongene neemeko zobushushu obuphezulu, i-gas chemistry enamandla kunye nemijikelo emide yenkqubo. I-graphite ye-Ultra porosity ephantsi kakhulu ibalulekile ukugcina ukuthembeka kwe-SiC epitaxy kunye nokucoceka. I-porosity ibhekisa kwii-pores ezincinci, zangaphakathi ezikhoyo ngaphakathi komzimba wegrafiti. Nangona umphezulu uthambile ngokugqibeleleyo, ii-pores zangaphakathi zinokubakho iigesi zenkqubo yokubamba, iintsalela kunye ne-chemistry yokucoca. I-porosity ephezulu ithetha umthamo wangaphakathi wokubamba, apho emva kokuvezwa kubushushu obuphezulu, izinto zinokususwa kancinci kancinci. Oku kususwa kwegesi akusoloko kuthe ngqo kwaye kunokukhokelela ekuqhumeni, okwenza inkqubo ibe nzima ukuyilawula. Kwi-SiC epitaxy, oku kuyingozi kakhulu. Xa iigesi zikhutshwa emzimbeni wegrafiti zinokufakwa kumjelo wegesi ngaphakathi kwigumbi le-epitaxy, zinegalelo kwiisuntswana ezingafunekiyo. Amasuntswana aya kufikelela kumphezulu we-wafer, nto leyo echaphazela ukukhula kwekristale kwaye inokukhokelela kwiziphene ezingalindelekanga ezifana nemingxunya engacwangciswanga, ukurhawuzelelwa komphezulu okanye utshintsho lwendawo kubukhulu be-wafer. Imeko eqhelekileyo edibana nayo ikwiindawo zokuvelisa apho i-clean fab ifumana iindawo ezintsha ze-graphite zenkqubo ye-EPIK. Iziphumo zokuqala zinokwamkeleka, nangona kunjalo njengoko imijikelo yobushushu iphinda-phinda, amazinga eziphene anokunyuka kwaye ukuhlolwa komzila wenkqubo kubandakanya imigca yegesi, iivalvu kunye namanqanaba enkqubo yokucoca akunakutyhila nto icacileyo. Rhoqo kutyhilwa ukuba imbangela yi-graphite ene-porosity ephantsi kwindawo yobushushu obuphezulu. Ukukhethwa kwe-graphite ene-porosity ephantsi kakhulu kunciphisa ngempumelelo lo mngcipheko ngokunciphisa ubungakanani bangaphakathi apho iintlobo ezibanjiweyo zinokufihlwa khona, kunciphisa amathuba okukhutshwa kwegesi ngequbuliso xa kushushu. Ikwanxulunyaniswa nokuthembeka okungcono koomatshini. Ulwakhiwo oluxineneyo lwe-graphite ene-porosity ephantsi kakhulu ludla ngokunika ukumelana okwandisiweyo kokuqhekeka njengoko i-graphite idlula kwi-thermal cycling ephindaphindayo. Ngaphezu koko, iindawo ezine-porosity ephantsi zikhuthaza ukuthembeka okuphuculweyo kokugquma. Xa i-SiC okanye ezinye izinto ezichaseneyo zigqunywe kwezi ndawo ze-graphite, zinamathela kakuhle kumphezulu ongena-porous kangako. Oku kusenokwenzeka ukuba kungenxa yokusondelana okwandisiweyo kokubopha phakathi kwezinto ezigqunyiweyo kunye negrafiti, nto leyo ephucula ukuqina kunye nobude bezinto ezigqunyiweyo kunye nokukwazi kwazo ukukrazula okanye ukuqhekeka. Ekugqibeleni, ukukhethwa kwegrafiti engaphantsi kakhulu kwisimo sokwenziwa kwemihla ngemihla, ngelixa iyimpahla yezinto ezibonakalayo, inika inzuzo ethe ngqo ekufezekiseni iziphumo ze-wafer ezizinzileyo, ezicocekileyo, neziqikelelweyo kwiinkqubo ze-SiC epitaxy eziphezulu.