Gukata amazi kare byateje imbere iterambere ry’ibikorwa byo gusukura cyangwa gusuka ivu. Muri iki gihe, gukata amazi hakoreshejwe plasma byabaye ikintu gikuruinzira yo gukataPlasma igizwe na electron, cations na radicals. Ingufu zikoreshwa muri plasma zituma electron zo hanze za gaze ikomoka mu buryo butari bwo zikurwaho, bityo izi electron zigahinduka cations.
Byongeye kandi, atome zidatunganye muri molekile zishobora gukurwaho hakoreshejwe ingufu kugira ngo hakorwe radicals zidafite amashanyarazi. Gucukura byumye bikoresha cations na radicals bigize plasma, aho cations ari anisotropic (zikwiriye gucukura mu cyerekezo runaka) naho radicals zikaba isotropic (zikwiriye gucukura mu byerekezo byose). Umubare wa radicals ni munini cyane ugereranije n'umubare wa cations. Muri iki gihe, gucukura byumye bigomba kuba isotropic nk'ukucukura byumye.
Ariko, gushushanya imiterere y’urumuri rw ...
1. Igipimo cy'Uburyo (A/R)
Ishusho ya 1. Igitekerezo cy'ikigereranyo cy'ibintu n'ingaruka z'iterambere ry'ikoranabuhanga kuri cyo
Igipimo cy'ubugari ni igipimo cy'ubugari butambitse n'uburebure buhagaze (ni ukuvuga uburebure bugabanijwemo ubugari). Uko igipimo cy'ingenzi (CD) cy'uruziga kiba gito, ni ko igipimo cy'ubugari kiba kinini. Ni ukuvuga ko, iyo agaciro k'igipimo cy'ubugari ka 10 n'ubugari bwa 10nm, uburebure bw'umwobo wacukuwe mu gihe cyo gukata bugomba kuba 100nm. Kubwibyo, ku bicuruzwa byo mu gisekuru gitaha bisaba ultra-miniaturization (2D) cyangwa high density (3D), igipimo cy'ubugari buhanitse cyane kirakenewe kugira ngo harebwe ko cations zishobora kwinjira mu firime yo hasi mu gihe cyo gukata.
Kugira ngo hagerwe ku ikoranabuhanga rya ultra-miniaturization rifite urwego rw'ingenzi ruri munsi ya 10nm mu bicuruzwa bya 2D, agaciro ka capacitor aspect ratio ya dynamic random access memory (DRAM) kagomba kuguma hejuru ya 100. Mu buryo nk'ubwo, 3D NAND flash memory nayo isaba agaciro kanini ka aspect ratio kugira ngo ishyire hamwe 256 layers cyangwa zirenga za cell stacking layers. Nubwo ibisabwa ku zindi nzira byuzuzwa, ibicuruzwa bisabwa ntibishobora gukorwa iyoinzira yo gukatantabwo ijyanye n'ibipimo ngenderwaho. Niyo mpamvu ikoranabuhanga ryo gushushanya rigenda rirushaho kuba ingenzi.
2. Incamake y'uburyo plasma icukurwamo
Ishusho ya 2. Kumenya inkomoko ya gazi mu maraso hakurikijwe ubwoko bwa firime
Iyo umuyoboro w'ubururu ukoreshejwe, uko umuyoboro urushaho kuba muto, niko byoroha ko amazi yinjira, ari byo bita capillary phenomenon. Ariko, iyo hagomba gucukurwa umwobo (ufunze) mu gace kagaragara, kwinjiramo kw'amazi biragorana cyane. Kubera iyo mpamvu, kubera ko ingano y'ingenzi y'uruziga yari hagati ya 3um na 5um mu myaka ya za 1970, yumagushushanyabuhoro buhoro byasimbuye gushushanya amazi nk'ikintu gisanzwe. Ni ukuvuga ko nubwo byahinduwe ioni, byoroshye kwinjira mu myobo miremire kuko ingano ya molekile imwe ari ntoya ugereranyije n'iya molekile y'umuti wa polymeri w'umwimerere.
Mu gihe cyo gukata plasma, imbere mu cyumba gitunganywamo ibikoresho bigomba guhindurwa kugira ngo bibe byangiritse mbere yo gutera umwuka ukomoka kuri plasma ukwiriye urwego rukenewe. Mu gihe cyo gukata ibyuma bya okiside ikomeye, hagomba gukoreshwa imyuka ikomeye ikomoka kuri fluoride ya karuboni. Ku bikoresho bya silikoni cyangwa ibyuma bidakomeye, hagomba gukoreshwa imyuka ikomoka kuri plasma ikomoka kuri chlorine.
None se, urwego rw'irembo n'urwego rw'ingufu rwa silikoni dioxyde (SiO2) rugomba gucukurwaho gute?
Ubwa mbere, ku gice cy’irembo, silikoni igomba gukurwaho hakoreshejwe plasma ishingiye kuri chlorine (silicon + chlorine) hamwe n’uburyo bwo gupima polysilicon. Ku gice cyo hasi cy’ingufu zirinda ubushyuhe, filime ya silikoni dioxyde igomba gupima mu ntambwe ebyiri hakoreshejwe gaze ya plasma ishingiye kuri fluoride (silicon dioxyde + carbon tetrafluoride) hamwe n’uburyo bwo gupima burushijeho kuba bwiza kandi bukora neza.
3. Uburyo bwo gukata iron (RIE cyangwa physicochemical etching)
Ishusho ya 3. Ibyiza byo gucukura iron (anisotropy n'igipimo cyo gucukura kiri hejuru)
Plasma irimo radicals zitagira isotropic na cations za anisotropic, none se ikora ite anisotropic etching?
Gucukura plasma byumye bikorwa cyane cyane hakoreshejwe uburyo bwo gucukura ion (RIE, Reactive Ion Etching) cyangwa gukoresha ubu buryo. Ishingiro ry'uburyo bwa RIE ni uguca intege imbaraga zo gufatanya hagati y'uturemangingo tw'ingenzi muri filime binyuze mu gutera agace gacukura hakoreshejwe uburyo bwa anisotropic. Agace gacitse intege gashyirwamo ibintu bidafite ishingiro, bihujwe n'uduce tugize urwo rwego, bigahinduka gaze (ikintu gihinduka umwuka) hanyuma kikarekurwa.
Nubwo radicals yigenga ifite imiterere ya isotropic, molekile zigize ubuso bwo hasi (imbaraga zayo zo gufatana zigabanuka bitewe n'igitero cya cations) zoroshye gufatwa na radicals yigenga zigahinduka ibintu bishya kuruta inkuta zo ku ruhande zifite imbaraga zikomeye zo gufatana. Kubwibyo, gukata hasi biba ikintu nyamukuru. Uduce twafashwe tuba gaze hamwe na radicals yigenga, zikurwamo hanyuma zigakurwa ku buso hakoreshejwe ifu.
Muri iki gihe, cations ziboneka binyuze mu bikorwa by'umubiri n'ingufu zikomoka ku binyabutabire zihuzwa kugira ngo hakorwe imiterere y'umubiri n'iya shimi, kandi igipimo cyo gukorwe (Igipimo cyo gukorwe, urugero rwo gukorwe mu gihe runaka) cyiyongeraho inshuro 10 ugereranije n'igihe cyo gukorwerwa cationic cyangwa gukorwerwa imiterere y'umubiri gusa. Ubu buryo ntibushobora kongera igipimo cyo gukorwerwa imiterere y'ingufu zikomoka ku gukorwerwa ndende, ahubwo bunakemura ikibazo cy'ibisigazwa bya polymer nyuma yo gukorwerwa. Ubu buryo bwitwa reactive ion etching (RIE). Urufunguzo rwo gutsinda kwa RIE etching ni ukubona umwuka ukomoka kuri plasma ukwiriye gukorwerwa filime. Icyitonderwa: Gukorwerwa plasma ni RIE etching, kandi byombi bishobora gufatwa nk'igitekerezo kimwe.
4. Igipimo cy'Ishusho n'Icyitegererezo cy'Imikorere y'Ishingiro
Ishusho ya 4. Igipimo cy'imikorere y'inyongera y'ibanze kijyanye n'igipimo cy'inyongera
Igipimo cyo gushisha bivuze uburebure bw'urupapuro rw'ibumba rwitezwe kugerwaho mu munota umwe. None se igipimo cyo gushisha bivuze iki bitewe n'igice ku gice ku kindi kuri wafer imwe?
Ibi bivuze ko ubujyakuzimu bw'ikigega butandukana bitewe n'igice ku gice cyacyo. Kubera iyo mpamvu, ni ngombwa cyane gushyiraho aho gusoza (EOP) aho gusoza bigomba guhagarara hashingiwe ku gipimo mpuzandengo cy'ikigega n'ubujyakuzimu bw'ikigega. Nubwo EOP yaba yashyizweho, hari ahantu hamwe na hamwe ubujyakuzimu bw'ikigega buba bwimbitse cyane (bwararenze urugero) cyangwa buke cyane (bwararenze urugero) kuruta uko byari biteganyijwe mbere. Ariko, gusoza bigira ingaruka mbi kurusha gusoza ikirenga mu gihe cyo gusoza. Kuko mu gihe cyo gusoza uburebure, igice cyasoza uburebure kizabangamira ibikorwa bikurikira nko gutera ion.
Hagati aho, guhitamo (bipimwe n'igipimo cya etch) ni ikimenyetso cy'ingenzi cy'imikorere y'uburyo bwo gushushanya. Igipimo ngenderwaho gishingiye ku kugereranya igipimo cya etch cy'urwego rwa mask (fotoresist film, oxide film, silicon nitride film, nibindi) n'urwego rw'icyerekezo. Ibi bivuze ko uko guhitamo ari ko hejuru, ni ko uru rwego rw'icyerekezo rushyirwa vuba. Uko urwego rwa miniaturization ruri hejuru, ni ko ibisabwa mu guhitamo ari byinshi kugira ngo hamenyekane neza ko imiterere myiza ishobora kugaragazwa neza. Kubera ko icyerekezo cyo gushushanya ari kigororotse, guhitamo kwa cationic etching ni hasi, mu gihe guhitamo kwa radical etching ari hejuru, ibyo bikanoza guhitamo kwa RIE.
5. Uburyo bwo gushushanya
Ishusho ya 5. Uburyo bwo gushushanya
Ubwa mbere, wafer ishyirwa mu itanura rya oxidation rifite ubushyuhe buri hagati ya 800 na 1000°C, hanyuma firime ya silikoni (SiO2) ifite ubushobozi bwo gushyushya hejuru ikorwa ku buso bwa wafer hakoreshejwe uburyo bwumye. Hanyuma, inzira yo gushyiramo ishyirwamo kugira ngo hakorwe urwego rwa silikoni cyangwa urwego ruyobora amashanyarazi kuri firime ya oxidation hakoreshejwe uburyo bwa chemical vapor deposition (CVD)/physical vapor deposition (PVD). Iyo urwego rwa silikoni rukozwe, inzira yo gukwirakwiza umwanda ishobora gukorwa kugira ngo hongerwe ubwikorezi bw'amazi nibiba ngombwa. Mu gihe cyo gukwirakwiza umwanda, imyanda myinshi ikunze kongerwamo inshuro nyinshi.
Muri iki gihe, urwego rwo kwirinda ubushyuhe n'urwego rwa polysilicon bigomba guhuzwa kugira ngo bicibwe. Ubwa mbere, hakoreshwa icyuma gikingira ubushyuhe. Nyuma yaho, hashyirwa agapfukamunwa ku gapira gakingira ubushyuhe hanyuma hagashyirwa ahantu hatose kugira ngo hagaragazwe ishusho wifuza (itagaragara n'amaso) kuri firime ikingira ubushyuhe. Iyo ishusho igaragajwe n'iterambere, icyuma gikingira ubushyuhe kiri mu gace gashobora gucibwamo n'ubushyuhe kirakurwaho. Hanyuma, wafer itunganywa na fotolithography yimurirwa mu buryo bwo gucibwa kugira ngo icibwe yumye.
Gucukura byumye bikorwa cyane cyane hakoreshejwe uburyo bwo gucukura ion bukoreshwa mu gucukura (RIE), aho gucukura bisubirwamo ahanini hakoreshejwe gusimbuza gazi ikomoka ku kintu ikwiriye buri firime. Gucukura byumye no gucukura byumye bigamije kongera igipimo cy’ubuso (agaciro ka A/R) cyo gucukura. Byongeye kandi, gusukura buri gihe birakenewe kugira ngo polymer ikusanyirize hasi mu mwobo (icyuho cyakozwe no gucukura). Ingingo y'ingenzi ni uko ibintu byose (nk'ibikoresho, gazi ikomoka ku kintu, igihe, imiterere n'uruhererekane) bigomba guhindurwa mu buryo bw'umwimerere kugira ngo umuti wo gusukura cyangwa gazi ikomoka ku kintu ishobora kumanuka ikagera hasi mu mwobo. Impinduka nto mu ihinduka ry'ikintu bisaba kongera kubara ibindi bintu, kandi iyi gahunda yo kongera kubara irasubirwamo kugeza igeze ku ntego ya buri cyiciro. Vuba aha, ibice bya monoatomic nka atomic layer deposition (ALD) byarushijeho kuba bito cyane. Kubwibyo, ikoranabuhanga ryo gucukura ririmo kwerekeza ku ikoreshwa ry'ubushyuhe n'umuvuduko muto. Uburyo bwo gucukura bugamije kugenzura urwego rw'ingenzi (CD) kugira ngo haboneke imiterere myiza kandi hamenyekane ko ibibazo biterwa n'uburyo bwo gucukura byirindwa, cyane cyane gucukura munsi y'ubuso n'ibibazo bijyanye no gukuraho ibisigazwa. Ingingo ebyiri zavuzwe haruguru ku gushushanya zigamije guha abasomyi gusobanukirwa intego y’uburyo bwo gushushanya, inzitizi zo kugera ku ntego zavuzwe haruguru, n’ibipimo by’imikorere byakoreshejwe mu gutsinda izo mbogamizi.
Igihe cyo kohereza: 10 Nzeri 2024