Kuna iya fahimtar shi ko da ba ku taɓa karanta ilimin kimiyyar lissafi ko lissafi ba, amma yana da ɗan sauƙi kuma ya dace da masu farawa. Idan kana son ƙarin sani game da CMOS, dole ne ka karanta abubuwan da ke cikin wannan batu, saboda kawai bayan fahimtar tsarin tafiyarwa (wato, tsarin samar da diode) zaka iya ci gaba da fahimtar abubuwan da ke gaba. Sa'an nan kuma bari mu koyi game da yadda aka samar da wannan CMOS a cikin kamfanin kafa a cikin wannan batu (daukar tsarin da ba shi da ci gaba a matsayin misali, CMOS na ci gaba da tsari ya bambanta a tsari da ka'idar samarwa).
Da farko, dole ne ku san cewa wafers ɗin da aka samo asali daga mai siyarwa (siliki silikimasu kawo kaya) ɗaya bayan ɗaya, tare da radius na 200mm (8 incifactory) ko 300mm (12-incifactory). Kamar yadda aka nuna a cikin hoton da ke ƙasa, yana kama da babban cake, wanda muke kira substrate.
Duk da haka, bai dace a gare mu mu kalli ta haka ba. Muna duba daga ƙasa zuwa sama kuma mu dubi ra'ayi na giciye, wanda ya zama adadi mai zuwa.
Na gaba, bari mu ga yadda samfurin CMOS ya bayyana. Tun da ainihin tsari yana buƙatar dubban matakai, zan yi magana game da manyan matakai na wafer 8-inch mafi sauƙi a nan.
Samar da Lafiya da Juyawa Layer:
Wato, ana dasa rijiyar a cikin ƙasa ta hanyar ion implantation (Ion Implantation, a nan gaba ana kiransa imp). Idan kuna son yin NMOS, kuna buƙatar dasa rijiyoyin P-type. Idan kuna son yin PMOS, kuna buƙatar dasa rijiyoyin N-type. Don jin daɗin ku, bari mu ɗauki NMOS a matsayin misali. Na'urar dasa ion tana sanya nau'ikan nau'ikan P da za a dasa su a cikin ma'aunin zuwa wani takamaiman zurfin, sannan a sanya su cikin zafi mai zafi a cikin bututun tanderun don kunna waɗannan ions tare da watsa su a kusa da su. Wannan yana kammala samar da rijiyar. Wannan shi ne abin da yake kama bayan an gama samarwa.
Bayan yin rijiyar, akwai wasu matakan dasa ion, wanda manufarsa ita ce sarrafa girman tashar tashar da kuma ƙarfin wuta. Kowa na iya kiransa da inversion Layer. Idan kana son yin NMOS, an dasa Layer inversion tare da nau'in nau'in P, kuma idan kana son yin PMOS, an dasa Layer na jujjuya tare da ions nau'in N. Bayan dasa, shi ne samfurin mai zuwa.
Akwai abubuwa da yawa a nan, kamar makamashi, kusurwa, ion maida hankali yayin dasawa da ion, da dai sauransu, waɗanda ba a haɗa su a cikin wannan batu ba, kuma na yi imani cewa idan kun san waɗannan abubuwa, dole ne ku zama mai ciki, kuma ku. dole ne a sami hanyar koyo su.
Yin SiO2:
Silicon dioxide (SiO2, daga nan ake kira oxide) za a yi daga baya. A cikin tsarin samar da CMOS, akwai hanyoyi da yawa don yin oxide. Anan, ana amfani da SiO2 a ƙarƙashin ƙofar, kuma kaurinsa kai tsaye yana rinjayar girman ƙarfin ƙarfin kofa da girman tashar halin yanzu. Saboda haka, mafi foundries zabi tanderu tube hadawan abu da iskar shaka hanya tare da mafi ingancin, mafi daidai kauri iko, da kuma mafi kyau uniformity a wannan mataki. A gaskiya ma, abu ne mai sauqi qwarai, wato, a cikin bututun tanderu tare da iskar oxygen, ana amfani da zafin jiki mai girma don ba da damar oxygen da silicon su amsa sinadarai don samar da SiO2. Ta wannan hanyar, ana samar da siriri mai bakin ciki na SiO2 a saman Si, kamar yadda aka nuna a cikin hoton da ke ƙasa.
Tabbas, akwai kuma takamaiman bayanai da yawa a nan, kamar digiri nawa ake buƙata, yawan adadin iskar oxygen da ake buƙata, tsawon lokacin da ake buƙatar babban zafin jiki, da dai sauransu. Waɗannan ba abin da muke la'akari ba ne yanzu, waɗannan su ne. ma takamaiman.
Samar da Ƙofar ƙarshen Poly:
Amma har yanzu bai kare ba. SiO2 yayi daidai da zaren, kuma ainihin ƙofar (Poly) ba ta fara ba tukuna. Don haka mataki na gaba shi ne mu shimfiɗa Layer na polysilicon akan SiO2 (polysilicon kuma ya ƙunshi nau'i na siliki guda ɗaya, amma tsarin lattice ya bambanta. Kar ku tambaye ni dalilin da yasa substrate yana amfani da siliki guda ɗaya kuma ƙofar yana amfani da polysilicon. littafi ne mai suna Semiconductor Physics Kuna iya koya game da shi abin kunya ~). Poly kuma babbar hanyar haɗi ce a cikin CMOS, amma ɓangaren poly shine Si, kuma ba za a iya samar da shi ta hanyar amsa kai tsaye tare da Si substrate kamar girma SiO2. Wannan yana buƙatar almara CVD (Chemical Vapor Deposition), wanda shine mayar da martani ta hanyar sinadarai a cikin vacuum kuma ya haifar da abin da aka samar akan wafer. A cikin wannan misali, abin da aka samar da shi shine polysilicon, sa'an nan kuma ya haye a kan wafer (a nan dole ne in faɗi cewa an samar da poly a cikin bututun tanderu ta CVD, don haka ba a yin na'urar CVD mai tsabta).
Amma polysilicon da aka kafa ta wannan hanyar za a haɗe shi a kan dukan wafer, kuma yana kama da wannan bayan hazo.
Bayyanar Poly da SiO2:
A wannan mataki, an kafa tsarin da muke so a tsaye, tare da poly a saman, SiO2 a kasa, da kuma substrate a kasa. Amma yanzu duk wafer ɗin kamar haka ne, kuma muna buƙatar takamaiman matsayi don zama tsarin "faucet". Don haka akwai mataki mafi mahimmanci a cikin dukan tsari - fallasa.
Mun fara yada wani Layer na photoresist a saman wafer, kuma ya zama kamar haka.
Sa'an nan kuma sanya abin rufe fuska da aka ƙayyade (an kwatanta tsarin kewayawa akan abin rufe fuska) akan shi, kuma a ƙarshe ya haskaka shi da haske na takamaiman tsayin raƙuman ruwa. Za a kunna mai ɗaukar hoto a cikin yankin da ba a ba da haske ba. Tunda wurin da abin rufe fuska ba ya haskaka ta hanyar hasken, wannan yanki na photoresisist ba a kunna ba.
Tun da kunna photoresist ne musamman sauki a wanke tafi da wani takamaiman sinadaran ruwa, yayin da unactivated photoresist ba za a iya wanke bãya, bayan sakawa a iska mai guba, da wani ruwa da ake amfani da su wanke kashe da kunna photoresist, kuma a karshe ya zama kamar wannan, da barin. photoresist inda Poly da SiO2 ke buƙatar riƙewa, da kuma cire mai ɗaukar hoto inda baya buƙatar riƙe shi.
Lokacin aikawa: Agusta-23-2024