Silicon Wafers vs. Gilashin Wafers: Menene Ainihin Tsabtace Mu? Daga Jigon Material zuwa Maganin Tsabtace Tsabtace Tsari

Ko da yake duka silicon da gilashin wafers suna raba burin gama gari na kasancewa "tsabta," ƙalubalen da yanayin gazawar da suke fuskanta yayin tsaftacewa sun bambanta sosai. Wannan bambance-bambancen ya samo asali ne daga abubuwan da ke tattare da kayan abu da ƙayyadaddun buƙatun silicon da gilashi, da kuma “falsafa” daban-daban na tsaftacewa da aikace-aikacen su na ƙarshe ke motsawa.

Da farko, bari mu fayyace: Menene daidai muke tsaftacewa? Wadanne gurɓatattun abubuwa ne ke tattare da su?

Ana iya rarraba gurɓatattun abubuwa zuwa rukuni huɗu:

1. Gurbataccen Barbashi

   • Dust, karfe barbashi, Organic barbashi, abrasive barbashi (daga CMP tsari), da dai sauransu.

   • Waɗannan gurɓatattun abubuwa na iya haifar da lahani, kamar guntun wando ko buɗe ido.

2. Kwayoyin Kwayoyin cuta

   • Ya haɗa da ragowar photoresist, ƙari na guduro, mai fata na ɗan adam, ragowar sauran ƙarfi, da sauransu.

   • Kwayoyin gurɓata yanayi na iya samar da abin rufe fuska waɗanda ke hana etching ko ion implantation da rage manne da sauran bakin ciki fina-finai.

3. Karfe Ion Contaminants

   • Iron, Copper, Sodium, Potassium, Calcium, da dai sauransu, wanda da farko ya fito daga kayan aiki, sunadarai, da hulɗar ɗan adam.

   • A cikin semiconductors, ions ƙarfe sune gurɓatattun “kisan”, suna gabatar da matakan makamashi a cikin rukunin da aka haramta, waɗanda ke haɓaka ɗigogi a halin yanzu, rage tsawon rayuwar mai ɗaukar kaya, kuma suna lalata kaddarorin lantarki sosai. A cikin gilashi, za su iya yin tasiri ga inganci da mannewa na fina-finai na bakin ciki na gaba.

4. Layer Oxide Layer

   • Don wafers na siliki: Silicon dioxide (Native Oxide) na bakin ciki a zahiri yana samuwa a saman iska. Kauri da daidaiton wannan Layer oxide yana da wuyar sarrafawa, kuma dole ne a cire shi gaba ɗaya yayin ƙirƙirar mahimman sifofi irin su gate oxides.

   • Don wafers ɗin gilashi: Gilashin kanta tsarin cibiyar sadarwar silica ne, don haka babu batun "cire Layer oxide na asali." Duk da haka, ƙila an gyaggyara fuskar saboda gurɓatawa, kuma wannan Layer yana buƙatar cirewa.

I. Muhimman Manufofin: Bambance-bambancen Tsakanin Ayyukan Wutar Lantarki da Cikakkiyar Jiki

• Silicon Wafers

  • Babban burin tsaftacewa shine tabbatar da aikin lantarki. Ƙayyadaddun ƙayyadaddun bayanai yawanci sun haɗa da ƙididdige ƙididdiga da girma (misali, barbashi ≥0.1μm dole ne a cire su yadda ya kamata), adadin ion ƙarfe (misali, Fe, Cu dole ne a sarrafa shi zuwa ≤10¹⁰ atoms/cm² ko ƙasa), da matakan ragowar kwayoyin halitta. Ko da gurɓataccen yanayi na iya haifar da guntun wando, ɗigon ruwa, ko gazawar amincin gate oxide.

• Gilashin Wafers

  • A matsayin ma'auni, ainihin buƙatun su ne kamala ta jiki da kwanciyar hankali na sinadarai. Ƙayyadaddun ƙayyadaddun ƙayyadaddun bayanai suna mayar da hankali kan abubuwan matakin macro kamar rashi tabo, tabo mara cirewa, da kuma kula da tarkace na asali da lissafi. Manufar tsaftacewa shine da farko don tabbatar da tsabtar gani da kuma mannewa mai kyau don matakai na gaba kamar sutura.

II. Yanayin Abu: Babban Bambanci Tsakanin Crystalline da Amorphous

• Siliki

  • Silicon abu ne mai kristal, kuma samansa a dabi'ance yana tsiro da silicon dioxide (SiO₂) oxide Layer mara kyau. Wannan Layer oxide yana haifar da haɗari ga aikin lantarki kuma dole ne a cire shi sosai kuma a cire shi daidai.

• Gilashin

  • Gilashi cibiyar sadarwa ce ta silica amorphous. Babban kayan sa yana kama da abun da ke tattare da siliki oxide Layer na silicon, wanda ke nufin ana iya yin shi da sauri ta hanyar hydrofluoric acid (HF) kuma yana iya kamuwa da yashwar alkali mai ƙarfi, wanda ke haifar da haɓakar rashin ƙarfi ko nakasawa. Wannan babban bambance-bambancen ya nuna cewa tsaftacewa na siliki na iya jure wa haske, sarrafa etching don cire gurɓataccen abu, yayin da tsabtace gilashin gilashin dole ne a yi shi tare da matsananciyar kulawa don guje wa lalata kayan tushe.

III. Kwatanta Maganin Tsabtatawa

Dangane da maƙasudan da aka ambata da halayen kayan aiki, hanyoyin tsaftacewa na silicon da wafers gilashi sun bambanta:

• Tsarin Tsabtace Wafer Gilashi

  • A halin yanzu, yawancin tsire-tsire masu sarrafa gilashi suna amfani da hanyoyin tsaftacewa bisa ga halayen kayan gilashi, suna dogara da farko a kan masu tsabtace alkaline masu rauni.

  • Halayen Wakilin Tsaftacewa:Wadannan ƙwararrun ma'aikatan tsaftacewa yawanci suna da raunin alkaline, tare da pH a kusa da 8-9. Yawanci suna ɗauke da abubuwan da suka shafi surfactants (misali, alkyl polyoxyethylene ether), magungunan ƙarfe na ƙarfe (misali, HEDP), da kayan aikin tsaftacewa na halitta, waɗanda aka ƙera don emulsify da bazuwar gurɓatattun ƙwayoyin halitta kamar mai da sawun yatsa, yayin da suke da ƙarancin lalacewa ga matrix ɗin gilashi.

  • Tsarin Tsari:Tsarin tsaftacewa na yau da kullum ya haɗa da yin amfani da ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun kayan tsaftacewa na alkaline a yanayin zafi daga dakin da zafin jiki zuwa 60 ° C, haɗe tare da tsaftacewa na ultrasonic. Bayan tsaftacewa, wafers suna ɗaukar matakan kurkura da yawa tare da ruwa mai tsafta da bushewa mai laushi (misali, jinkirin ɗagawa ko bushewar tururin IPA). Wannan tsari yadda ya kamata ya cika buƙatun wafer gilashin don tsabtar gani da tsafta gabaɗaya.

• Tsarin Tsabtace Silicon Wafer

  • Don sarrafa semiconductor, wafers na silicon yawanci suna jurewa daidaitaccen tsaftacewa na RCA, wanda shine ingantacciyar hanyar tsaftacewa wacce ke da tsari da tsari don magance kowane nau'in gurɓatawa, tabbatar da cewa an cika buƙatun aikin lantarki na na'urorin semiconductor.

IV. Lokacin Gilashin Ya Hadu Maɗaukakin Matsayin "Tsafta".

Lokacin da ake amfani da wafers na gilashi a cikin aikace-aikacen da ke buƙatar ƙididdige ƙididdiga na barbashi da matakan ion ƙarfe (misali, azaman abubuwan da ke cikin matakan semiconductor ko don kyawawan filayen jigon fim na bakin ciki), tsarin tsaftacewa na ciki na iya daina isa. A wannan yanayin, ana iya amfani da ƙa'idodin tsabtace semiconductor, gabatar da ingantaccen dabarun tsaftacewa na RCA.

Tushen wannan dabarar ita ce ta tsomawa da haɓaka daidaitattun sigogin tsari na RCA don daidaita yanayin gilashin:

• Cire Gurbacewar Halitta:Ana iya amfani da mafita na SPM ko ruwan lemun tsami mai laushi don lalata gurɓataccen abu ta hanyar iskar oxygen mai ƙarfi.

• Cire ɓangarorin:Maganin SC1 mai narkewa sosai ana amfani da shi a ƙananan yanayin zafi da ɗan gajeren lokacin jiyya don amfani da tarkace ta electrostatic da micro-etching effects don cire barbashi, yayin da rage lalata akan gilashin.

• Cire Karfe Ion:Ana amfani da maganin SC2 da aka diluted ko sauƙi mai tsarma hydrochloric acid/dilute nitric acid mafita don cire gurɓataccen ƙarfe ta hanyar chelation.

• Hanyoyi masu tsauri:DHF (di-ammonium fluoride) dole ne a kauce masa kwata-kwata don hana lalata kayan gilashin.

A cikin duka tsarin da aka gyara, haɗa fasahar megasonic yana haɓaka haɓakar ƙayyadaddun ƙayyadaddun nano masu girman gaske kuma yana da laushi a saman.

Kammalawa

Hanyoyin tsaftacewa don siliki da wafers ɗin gilashi shine sakamakon da babu makawa na aikin injiniya na baya dangane da buƙatun aikace-aikacen su na ƙarshe, kaddarorin kayan aiki, da halaye na zahiri da sinadarai. Tsaftace wafer siliki yana neman "tsaftar matakin atomic" don aikin lantarki, yayin da tsabtace gilashin wafer yana mai da hankali kan cimma "cikakkiyar, rashin lalacewa" saman jiki. Kamar yadda ake ƙara amfani da wafers na gilashi a cikin aikace-aikacen semiconductor, hanyoyin tsaftace su ba makawa za su rikiɗe fiye da tsaftacewar alkaline mai rauni na gargajiya, haɓaka ƙarin tsaftacewa, gyare-gyare na musamman kamar tsarin RCA da aka gyara don saduwa da ƙa'idodin tsabta.