Me yasa ake buƙatar bakin ciki?

A mataki na baya-karshen tsari, dawafer (siliki silikitare da da'irori a gaba) yana buƙatar yin bakin ciki a baya kafin dicing na gaba, waldawa da marufi don rage tsayin tsayin fakitin, rage girman kunshin guntu, haɓaka ingancin yaduwa na guntu, aikin lantarki, kaddarorin inji da rage adadin dicing. Back nika yana da abũbuwan amfãni daga high dace da kuma low cost. Ya maye gurbin al'adar rigar etching da ion etching matakai don zama mafi mahimmancin fasaha na bakin ciki na baya.

Wafer na bakin ciki

Yadda ake bakin ciki?

Babban tsari na wafer thinning a cikin gargajiya marufi tsari

Takamaiman matakai nawaferthinning ne to bond da wafer da za a sarrafa zuwa thinning fim, sa'an nan kuma amfani da injin don adsorb da thinning fim da guntu a kan shi zuwa porous yumbu wafer tebur, daidaita ciki da kuma waje madauwari jirgin cibiyar Lines na aiki surface na aiki surface na aiki surface na aikin. dabaran niƙa lu'u-lu'u mai siffar kofi zuwa tsakiyar waƙar siliki, da wafer siliki da dabaran niƙa suna juyawa a kusa da gaturansu don yanke-ciki. Nika ya ƙunshi matakai uku: m nika, lafiya nika da goge.

Wafern da ke fitowa daga masana'antar wafer ana niƙa ne da baya-baya don siriri da kaurin da ake buƙata don tattarawa. Lokacin niƙa wafer, ana buƙatar tef ɗin a shafa a gaba (Active Area) don kare yankin kewaye, kuma gefen baya yana ƙasa a lokaci guda. Bayan nika, cire tef ɗin kuma auna kauri.
Hanyoyin niƙa waɗanda aka yi nasarar amfani da su zuwa shirye-shiryen wafer na silicon sun haɗa da jujjuyawar tebur,siliki silikijuyawa nika, nika mai gefe biyu, da dai sauransu Tare da ƙarin haɓaka ingancin buƙatun buƙatun buƙatun buƙatun siliki guda ɗaya, ana ba da shawarar sabbin fasahohin niƙa koyaushe, irin su TAIKO niƙa, injin injin injin, polishing niƙa da niƙa na duniya.

Rotary tebur nika:

Rotary tebur nika (Rotary tebur nika) shi ne farkon nika tsari da ake amfani da su a shirye-shiryen silicon wafer da baya thinning. An nuna ka'idarsa a hoto na 1. Ana gyara wafern siliki akan kofuna na tsotsa na tebur mai jujjuya, kuma suna juya synchronously tare da tebur mai juyawa. Wafers na silicon da kansu ba sa juyawa a kusa da axis; Ana ciyar da dabaran niƙa axially yayin da take juyawa cikin sauri, kuma diamita na dabaran niƙa ya fi diamita na wafer silicon. Akwai nau'i biyu na niƙa tebur na jujjuya: niƙawar fuska da niƙawar fuska. A cikin niƙa ta fuskar fuska, ƙafar niƙa ya fi diamita na siliki girma, kuma ƙwanƙwasa ƙafar ƙafar yana ci gaba da ciyarwa tare da axial shugabanci har sai an sarrafa abin da ya wuce, sa'an nan kuma ana jujjuya wafer silicon a ƙarƙashin tuƙin tebur na jujjuya; a fuskar niƙawar tangential, dabaran niƙa tana ciyarwa tare da jagorar axial, kuma wafer siliki yana ci gaba da jujjuya shi a ƙarƙashin tuƙin diski mai jujjuya, kuma ana kammala niƙa ta hanyar ciyarwa (maimaitawa) ko ciyarwa mai rarrafe (creepfeed).

Hoto na 1, tsari na tsarin niƙa tebur mai jujjuya (fuskar tangential).

Idan aka kwatanta da hanyar niƙa, rotary tebur nika yana da abũbuwan amfãni daga high cire kudi, kananan surface lalacewa, da kuma sauki sarrafa kansa. Duk da haka, ainihin wurin niƙa (niƙa mai aiki) B da kuma yanke-in θ (kusurwar da ke tsakanin da'irar waje na motar nika da kuma da'irar waje na silicon wafer) a cikin tsarin nika yana canzawa tare da canjin matsayi na yanke. daga cikin dabaran niƙa, yana haifar da ƙarfin niƙa mara ƙarfi, yana sa ya zama da wahala a sami daidaiton yanayi mai kyau (ƙimar TTV mai girma), da sauƙin haifar da lahani kamar rugujewar gefe da rugujewar gefe. The Rotary tebur nika fasahar da aka yafi amfani don sarrafa guda-crystal silicon wafers kasa 200mm. Ƙara girman girman wafers silicon-crystal guda ɗaya ya sanya buƙatu mafi girma don daidaiton farfajiya da daidaiton motsi na kayan aiki na kayan aiki, don haka niƙa tebur ɗin rotary bai dace da niƙa na siliki guda-crystal wafers sama da 300mm ba.
Domin inganta aikin niƙa, kasuwanci jirgin sama tangential nika kayan aiki yawanci rungumi a Multi-nika dabaran tsarin. Misali, saitin ingantattun ƙafafun niƙa da ɗumbin ƙafafun niƙa masu kyau suna sanye da kayan aiki, kuma tebur ɗin rotary yana jujjuya da'irar guda ɗaya don kammala ƙaƙƙarfan niƙa da niƙa mai kyau bi da bi. Irin wannan kayan aiki ya haɗa da G-500DS na Kamfanin GTI na Amurka (Hoto 2).

Hoto 2, G-500DS Rotary Tebur kayan niƙa na Kamfanin GTI a Amurka

Silicon wafer jujjuya niƙa:

Domin saduwa da buƙatun babban-size siliki wafer shiri da baya thinning aiki, da kuma samun daidaitattun surface tare da mai kyau TTV darajar. A cikin 1988, masanin Jafananci Matsui ya ba da shawarar hanyar jujjuya wafer na silicon (in-feedgrinding). An nuna ka'idarsa a cikin Hoto 3. The single crystal silicon wafer da kofin-dimbin lu'u-lu'u nika dabaran adsorbed a kan workbench juya a kusa da nasu gatari, da kuma nika dabaran ci gaba da ciyar tare da axial shugabanci a lokaci guda. Daga cikin su, diamita na dabaran niƙa ya fi diamita na wafer siliki da aka sarrafa, kuma kewayenta yana wucewa ta tsakiyar wafer siliki. Domin rage karfin nika da rage zafin nika, yawanci ana datsa kofin tsotsa a cikin wani nau'i mai ma'ana ko maɗaukaki ko kuma kusurwar tsakanin maɗauran ƙafar ƙafar ƙafar ƙafar ƙafar ƙafa da ƙwayar tsotsa don tabbatar da niƙa tsakanin ma'amala da juna. dabaran nika da wafer siliki.

Hoto 3, Tsarin tsari na ka'idar jujjuyawar ka'idar siliki

Idan aka kwatanta da rotary tebur nika, silicon wafer rotary nika yana da wadannan abũbuwan amfãni: ① Single-lokaci guda-wafer nika iya sarrafa manyan-size silicon wafers a kan 300mm; ② Ainihin yanki na niƙa B da yankan kusurwa θ sun kasance akai-akai, kuma ƙarfin niƙa yana da kwanciyar hankali; ③ By daidaita karkata kwana tsakanin nika dabaran axis da silicon wafer axis, da surface siffar guda crystal silicon wafer za a iya rayayye sarrafa don samun mafi ingancin surface daidaito. Bugu da kari, da nika yankin da yankan kwana θ na silicon wafer Rotary nika kuma suna da abũbuwan amfãni daga babban gefe nika, sauki online kauri da kuma surface ingancin ganewa da kuma iko, m kayan aiki tsarin, sauki Multi-tasha hadedde nika, da kuma high nika yadda ya dace.
Domin inganta samarwa yadda ya dace da kuma saduwa da bukatun semiconductor samar Lines, kasuwanci nika kayan aiki bisa ka'idar silicon wafer Rotary nika rungumi dabi'ar Multi-spindle Multi-tasha tsarin, wanda zai iya kammala m nika da lafiya nika a daya loading da saukewa. . Haɗe tare da sauran kayan taimako, zai iya gane cikakken atomatik nika na silikon wafers "bushe-a-bushe" da "kaset zuwa kaset".

Nika mai gefe biyu:

Lokacin da silicon wafer rotary nika tafiyar da babba da ƙananan saman na silicon wafer, da workpiece bukatar a juye da za'ayi a matakai, wanda ya iyakance yadda ya dace. A lokaci guda, siliki wafer rotary nika yana da kurakurai na saman kwafi (kwafi) da alamomin niƙa (alamar niƙa), kuma ba shi yiwuwa a kawar da lahani yadda ya kamata kamar waviness da taper akan saman wafer silicon ɗin kristal guda ɗaya bayan yankan waya. (multi-saw), kamar yadda aka nuna a cikin Hoto na 4. Don shawo kan lahani na sama, fasahar niƙa mai gefe biyu (biyu) ta bayyana a cikin 1990s, kuma an nuna ka'idarta a cikin Hoto. 5. Maƙuman da aka rarraba a hankali a ɓangarorin biyu suna matsa wafer siliki guda ɗaya a cikin zoben riƙewa kuma suna juyawa a hankali ta abin nadi. Ƙafafun niƙa na lu'u-lu'u nau'i-nau'i nau'i-nau'i suna da ɗanɗano a ɓangarorin biyu na wafer siliki guda ɗaya. Ƙunƙarar igiyar wutar lantarki mai ɗauke da iska, suna jujjuyawa zuwa wasu wurare kuma suna ciyar da axially don cimma niƙa mai gefe biyu na wafer siliki ɗaya. Kamar yadda ake iya gani daga adadi, niƙa mai gefe biyu na iya cire waviness yadda ya kamata da taper a saman kariyar silikon kristal guda ɗaya bayan yankan waya. Dangane da tsarin tsari na axis dabaran niƙa, niƙa mai gefe biyu na iya zama a kwance da tsaye. Daga cikin su, a kwance nika mai gefe biyu na iya yadda ya kamata rage tasirin nakasar silicon wafer lalacewa ta hanyar matattun nauyin siliki na wafer akan ingancin niƙa, kuma yana da sauƙi don tabbatar da yanayin aiwatar da niƙa a ɓangarorin biyu na silicon siliki guda ɗaya. wafer iri ɗaya ne, kuma ɓangarorin abrasive da guntuwar niƙa ba su da sauƙi a tsaya a saman waƙar siliki guda ɗaya. Yana da in mun gwada da manufa nika hanya.

Hoto na 4, "Kuskure kwafin" da kuma sa alamar lahani a cikin jujjuyawar wafer silicon

Hoto na 5, zane mai tsari na ƙa'idar niƙa mai gefe biyu

Tebu 1 yana nuna kwatancen tsakanin niƙa da niƙa mai gefe biyu na sama nau'ikan wafers silicon crystal guda uku na sama. Ana amfani da niƙa mai gefe biyu don sarrafa wafer silicon ƙasa da 200mm, kuma yana da yawan amfanin ƙasa. Saboda yin amfani da ƙayyadaddun ƙayyadaddun ƙafafun niƙa, niƙa na siliki guda-crystal wafers na iya samun inganci mafi girma fiye da na niƙa mai gefe biyu. Saboda haka, duka silicon wafer Rotary nika da biyu-gefe nika iya saduwa da aiki ingancin bukatun na al'ada 300mm silicon wafers, kuma a halin yanzu su ne mafi muhimmanci flattening sarrafa hanyoyin. Lokacin zabar hanyar sarrafa walƙiya ta siliki, ya zama dole a yi la'akari sosai da buƙatun girman diamita, ingancin saman, da fasahar sarrafa wafer na wafer silicon wafer guda-crystal. Ƙunƙarar baya na wafer ɗin zai iya zaɓar hanyar sarrafawa mai gefe ɗaya kawai, kamar hanyar siliki wafer rotary nika.

Baya ga zaɓin hanyar niƙa a cikin niƙa na silicon wafer, Hakanan wajibi ne don ƙayyade zaɓin sigogin tsari masu ma'ana kamar matsi mai kyau, girman hatsi mai niƙa, ɗaure dabaran dabaran, saurin niƙa, saurin silicon wafer, niƙa ruwa danko da yawan kwarara, da sauransu, da kuma ƙayyade hanyar tsari mai ma'ana. Yawanci, wani segmented nika tsari ciki har da m nika, Semi-kammala nika, karewa nika, walƙiya-free nika da jinkirin goyon baya da ake amfani da su samu guda crystal silicon wafers tare da high aiki yadda ya dace, high surface flatness da low surface lalacewa.