Kuyerera kwemaitiro e semiconductor

Unogona kuinzwisisa kunyangwe usati wambodzidza fizikisi kana masvomhu, asi iri nyore uye yakakodzera kune vanotanga. Kana uchida kuziva zvakawanda nezveCMOS, unofanirwa kuverenga zviri muchinyorwa chino, nekuti mushure mekunzwisisa mafambiro emaitiro (ndiko kuti, maitiro ekugadzira diode) ndipo paunokwanisa kuramba uchinzwisisa zvirimo zvinotevera. Ngatidzidzei nezvekuti iyi CMOS inogadzirwa sei mukambani yekugadzira foundry muchinyorwa chino (tichitora maitiro asiri epamberi semuenzaniso, CMOS yemaitiro epamberi yakasiyana muchimiro uye musimboti wekugadzira).

Chekutanga, unofanira kuziva kuti mawafer anowanikwa nefekitori kubva kumutengesi (chifukidziro chesiliconmupi) mumwe nemumwe, ane radius ye200mm (8-inchfekitori) kana 300mm (12-inchSezvakaratidzwa mumufananidzo uri pazasi, chaizvoizvo yakafanana nekeke hombe, yatinodaidza kuti substrate.

Zvisinei, hazvina kunaka kuti tizvitarise nenzira iyi. Tinotarisa kubva pasi tichienda kumusoro totarisa maonero echikamu chakasiyana, icho chinova mufananidzo unotevera.

Tevere, ngationei kuti modhi yeCMOS inotaridzika sei. Sezvo maitiro chaiwo achida zviuru zvematanho, ndichataura nezvematanho makuru ewafer iri nyore ye 8-inch pano.

 

 

Kugadzira Mutsetse uye Chigadziko Chekuchinjika:

Kureva kuti, tsime rinoiswa mu substrate ne ion implantation (Ion Implantation, pano inonzi imp). Kana uchida kugadzira NMOS, unofanirwa kuisa P-type wells. Kana uchida kugadzira PMOS, unofanirwa kuisa N-type wells. Kuti zvikuitire nyore, ngatitorei NMOS semuenzaniso. Muchina we ion implantation unoisa P-type elements dzinofanira kuiswa mu substrate kusvika pakadzika, wobva wadzipisa pakupisa kwakanyanya mu furnace tube kuti iite kuti ma ions aya ashande uye adziparadzire. Izvi zvinopedzisa kugadzirwa kwetsime. Izvi ndizvo zvinoita mushure mekunge kugadzirwa kwapera.

Mushure mekugadzira tsime, kune mamwe matanho ekuisa maion, chinangwa chayo ndechekudzora saizi yemagetsi emugero uye voltage yemuganho. Munhu wese anogona kuidana kuti inversion layer. Kana uchida kugadzira NMOS, inversion layer inoiswa nemaion emhando yeP, uye kana uchida kugadzira PMOS, inversion layer inoiswa nemaion emhando yeN. Mushure mekuisirwa, ndiyo modhi inotevera.

Pane zvakawanda zvirimo pano, zvakaita sesimba, kona, kuwanda kwemaion panguva yekuisa maion, nezvimwewo, izvo zvisina kunyorwa muchinyorwa chino, uye ndinotenda kuti kana uchiziva zvinhu izvozvo, unofanira kunge uri munhu anozvinzwisisa, uye unofanira kunge uine nzira yekuzvidzidza.

 

Kugadzira SiO2:

Silicon dioxide (SiO2, inozivikanwawo se oxide) ichagadzirwa gare gare. Mukugadzirwa kweCMOS, kune nzira dzakawanda dzekugadzira oxide. Pano, SiO2 inoshandiswa pasi pegedhi, uye ukobvu hwayo hunokanganisa zvakananga saizi ye threshold voltage nehukuru hwe channel current. Nokudaro, vazhinji vanogadzira matombo vanosarudza nzira ye oxidation ye furnace tube ine mhando yepamusoro, kutonga kwakanyatsojeka kweukobvu, uye kufanana kwakanakisa padanho iri. Kutaura zvazviri, zviri nyore kwazvo, kureva kuti, mu furnace tube ine oxygen, tembiricha yakakwira inoshandiswa kubvumira oksijeni nesilicon kuti zviite makemikari kugadzira SiO2. Nenzira iyi, chidimbu chakatetepa cheSiO2 chinogadzirwa pamusoro peSi, sezvakaratidzwa mumufananidzo uri pazasi.

Ehezve, kunewo ruzivo rwakawanda rwakananga pano, rwakadai sekuti madhigirii mangani anodiwa, huwandu hwakawanda hweokisijeni hunodiwa, kuti tembiricha yakakwira inodiwa kwenguva yakareba sei, nezvimwewo. Izvi hazvisi izvo zvatiri kufunga nezvazvo pari zvino, izvo zvakanyatsojeka.

Kuumbwa kwegedhi rekupedzisira Poly:

Asi hazvisati zvapera. SiO2 inongofanana neshinda, uye gedhi chairo (Poly) harisati ratanga. Saka danho redu rinotevera nderekuisa polysilicon paSiO2 (polysilicon inoumbwawo nechinhu chimwe chete chesilicon, asi kurongeka kwelattice kwakasiyana. Musandibvunze kuti sei substrate ichishandisa single crystal silicon uye gedhi richishandisa polysilicon. Pane bhuku rinonzi Semiconductor Physics. Unogona kudzidza nezvazvo. Zvinonyadzisa ~). Poly ilink yakakosha zvikuru muCMOS, asi chikamu chepoly ndiSi, uye hachigone kugadzirwa nekuita zvakananga neSi substrate sekukura kweSiO2. Izvi zvinoda CVD (Chemical Vapor Deposition), iyo inoshanda nemakemikari mu vacuum uye inokonzeresa chinhu chinogadzirwa pawafer. Mumuenzaniso uyu, chinhu chinogadzirwa ipolysilicon, uye chinokonzeresa pawafer (pano ndinofanira kutaura kuti poly inogadzirwa muchubhu yefurnace neCVD, saka kugadzirwa kwepoly hakuitwe nemuchina weCVD wakachena).

Asi polysilicon inoumbwa nenzira iyi ichawira pamusoro pewafer yese, uye zvinoita seizvi mushure mekunaya kwemvura.

 

Kuonekwa kwePoly neSiO2:

Padanho iri, chimiro chakamira chatinoda chakagadzirwa, chine poly pamusoro, SiO2 pasi, uye substrate pasi. Asi ikozvino wafer yese yakaita seizvi, uye tinongoda nzvimbo chaiyo kuti ive chimiro che "pombi". Saka pane danho rakakosha kwazvo mukuita kwese - kuratidzwa.
Tinotanga taisa jira rekudzivirira kupisa pamusoro pewafer, uye zvinova seizvi.

Wobva waisa mask yakatsanangurwa (maitiro edunhu akatsanangurwa pa mask) pairi, wozopedzisira waivhenekesa nechiedza chewavelength chaiyo. Iyo photoresist ichashanda munzvimbo yakavhenekerwa. Sezvo nzvimbo yakavharirwa ne mask isina kuvhenekerwa nechiedza, chidimbu ichi che photoresist hachishande.

Sezvo activated photoresist iri nyore kugezwa nemvura chaiyo yemakemikari, nepo unactivated photoresist isingagezwe, mushure mekupiswa nemwaranzi, mvura chaiyo inoshandiswa kugezwa activated photoresist, uye pakupedzisira inova seizvi, ichisiya photoresist panofanira kuchengetwa Poly neSiO2, uye ichibvisa photoresist paisingade kuchengetwa.