YDiffusion vs Ion Implantation
Qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv thiab ion implantation tuaj yeem nkag siab thaum koj nkag siab tias qhov diffusion thiab ion implantation yog dab tsi. Ua ntej ntawm tag nrho cov, nws yuav tsum tau hais tias diffusion thiab ion implantation yog ob nqe lus hais txog semiconductors. Lawv yog cov txheej txheem siv los qhia dopant atoms rau hauv semiconductors. Kab lus no yog hais txog ob txheej txheem, lawv qhov sib txawv loj, qhov zoo, thiab qhov tsis zoo.
Diffusion yog dab tsi?
Diffusion yog ib qho ntawm cov txheej txheem tseem ceeb siv los qhia cov impurities rau hauv semiconductors. Txoj kev no txiav txim siab qhov kev txav ntawm dopant ntawm atomic scale thiab, qhov tseem ceeb, cov txheej txheem tshwm sim los ntawm qhov concentration gradient. Diffusion txheej txheem yog ua nyob rau hauv lub tshuab hu ua "diffusion furnaces". Nws yog kim kim thiab yog heev.
Muaj peb qhov chaw tseem ceeb ntawm dopants: gaseous, kua, thiab khib nyiab thiab gaseous qhov chaw yog ib qho kev siv dav tshaj plaws hauv cov txheej txheem no (Kev ntseeg tau thiab yooj yim qhov chaw: BF 3, PH3, AsH3). Nyob rau hauv cov txheej txheem no, cov pa roj reacts nrog oxygen ntawm lub wafer nto ua rau ib tug dopant oxide. Tom ntej no, nws diffuses mus rau hauv Silicon, tsim ib tug uniform dopant concentration nyob rau saum npoo. Cov kua dej muaj nyob rau hauv ob hom: bubblers thiab spin on dopant. Bubblers hloov ua kua rau hauv vapor kom hnov mob nrog oxygen thiab tom qab ntawd tsim cov dopant oxide ntawm qhov chaw wafer. Spin on dopants yog cov kev daws teeb meem ntawm ziab daim ntawv doped SiO2 txheej. Cov khoom muaj xws li ob daim ntawv: ntsiav tshuaj los yog granular daim ntawv thiab disc los yog wafer daim ntawv. Boron nitride (BN) discs feem ntau yog siv cov khoom siv uas tuaj yeem oxidized ntawm 750 - 1100 0 C.
Yooj yim diffusion ntawm ib yam khoom (xiav) vim yog qhov concentration gradient hla ib daim nyias nyias (liab liab).
Ion Implantation yog dab tsi?
Ion implantation yog lwm cov txheej txheem ntawm kev qhia impurities (dopants) rau semiconductors. Nws yog cov txheej txheem kub-kub. Qhov no yog suav tias yog lwm txoj hauv kev kub-kub diffusion rau kev qhia dopants. Nyob rau hauv cov txheej txheem no, ib tug nqaj ntawm lub zog ions yog tsom rau lub hom phiaj semiconductor. Kev sib tsoo ntawm cov ions nrog cov lattice atoms ua rau muaj kev cuam tshuam ntawm cov qauv siv lead ua. Cov kauj ruam tom ntej yog annealing, uas yog ua raws li los kho qhov teeb meem distortion.
Qee qhov zoo ntawm cov txheej txheem ion implantation suav nrog kev tswj xyuas qhov tob ntawm qhov profile thiab ntau npaum li cas, tsis tshua nkag siab rau cov txheej txheem ntxuav saum npoo, thiab nws muaj ntau yam khoom siv npog ntsej muag xws li photoresist, poly-Si, oxides, thiab hlau.
Qhov txawv ntawm Diffusion thiab Ion Implantation yog dab tsi?
• Hauv kev nthuav dav, cov khoom sib kis tau los ntawm kev txav mus los ntawm cov cheeb tsam siab dua mus rau thaj tsam qis dua. Ion implantation cuam tshuam nrog kev foob pob ntawm lub substrate nrog ions, ua kom nrawm dua kom nrawm dua.
• Cov txiaj ntsig zoo: Kev sib faib ua kom tsis muaj kev puas tsuaj thiab kev tsim cov khoom lag luam kuj tuaj yeem ua tau. Ion implantation yog cov txheej txheem uas tsis tshua muaj kub. Nws tso cai rau koj los tswj cov koob meej meej thiab qhov tob. Ion implantation kuj ua tau los ntawm cov txheej nyias ntawm oxides thiab nitrides. Nws kuj suav nrog lub sijhawm luv luv.
• Qhov tsis zoo: Kev sib kis yog txwv rau cov khoom solubility thiab nws yog txheej txheem kub. Cov junctions ntiav thiab tsawg npaum li cas yog nyuaj rau cov txheej txheem ntawm diffusion. Ion implantation suav nrog tus nqi tshaj tawm rau cov txheej txheem annealing.
• Diffusion muaj ib qho isotropic dopant profile whereas ion implantation muaj anisotropic dopant profile.
Summary:
Ion Implantation vs Diffusion
Diffusion thiab ion implantation yog ob txoj hauv kev qhia cov impurities rau semiconductors (Silicon - Si) los tswj cov feem ntau ntawm cov cab kuj thiab cov txheej txheem resistivity. Hauv diffusion, dopant atoms txav los ntawm qhov chaw mus rau hauv Silicon los ntawm kev siv cov concentration gradient. Nws yog los ntawm kev hloov pauv lossis interstitial diffusion mechanisms. Nyob rau hauv ion implantation, dopant atoms yog ntxiv dag zog rau hauv Silicon los ntawm txhaj ib lub zog ion beam. Diffusion yog txheej txheem kub thaum ion implantation yog txheej txheem qis. Dopant concentration thiab qhov sib txuas qhov tob tuaj yeem tswj tau hauv ion implantation, tab sis nws tsis tuaj yeem tswj tau hauv cov txheej txheem diffusion. Diffusion muaj ib qho isotropic dopant profile whereas ion implantation muaj ib qho anisotropic dopant profile.
