Ion implantation yog ib txoj hauv kev ntxiv qee qhov nyiaj thiab hom impurities rau hauv cov khoom siv semiconductor los hloov lawv cov khoom hluav taws xob. Tus nqi thiab kev faib tawm ntawm impurities tuaj yeem tswj tau meej.
Ntu 1
Vim li cas thiaj siv cov txheej txheem ion implantation
Hauv kev tsim cov khoom siv hluav taws xob semiconductor, P / N cheeb tsam doping ntawm tsoossilicon waferstuaj yeem ua tiav los ntawm diffusion. Txawm li cas los xij, qhov diffusion tas li ntawm impurity atoms hauvsilicon carbidetsis tshua muaj neeg tsawg, yog li nws tsis muaj tseeb kom ua tiav kev xaiv doping los ntawm cov txheej txheem diffusion, raws li qhia hauv daim duab 1. Ntawm qhov tod tes, qhov kub thiab txias ntawm ion implantation yog qis dua li cov txheej txheem diffusion, thiab hloov tau yooj yim dua thiab raug doping faib tau. raug tsim.
Daim duab 1 Kev sib piv ntawm diffusion thiab ion implantation doping technologies hauv silicon carbide cov ntaub ntawv
Ntu 2
Yuav ua li cas kom tiavsilicon carbideion implantation
Cov khoom siv hluav taws xob ion implantation raug siv hauv cov txheej txheem silicon carbide cov txheej txheem tsim khoom feem ntau muaj cov khoom siv ion, ntshav, cov khoom siv aspiration, cov hlau nplaum analytical, ion beams, acceleration tubes, process chambers, thiab scanning disks, raws li qhia hauv daim duab 2.
Daim duab 2 Schematic daim duab ntawm silicon carbide high-zog ion implantation khoom
(Qhov chaw: "Semiconductor Manufacturing Technology")
SiC ion implantation feem ntau yog ua los ntawm qhov kub thiab txias, uas tuaj yeem txo qhov kev puas tsuaj rau cov iav siv lead ua los ntawm ion bombardment. Rau4H-SiC wafers, zus tau tej cov N-hom cheeb tsam feem ntau yog ua tiav los ntawm implanting nitrogen thiab phosphorus ions, thiab zus tau tej covP-typeCov cheeb tsam feem ntau yog ua tiav los ntawm kev cog cov txhuas ions thiab boron ions.
Table 1. Piv txwv ntawm kev xaiv doping hauv SiC cov cuab yeej tsim khoom
(Source: Kimoto, Cooper, Fundamentals of Silicon Carbide Technology: Loj hlob, Cwj Pwm, Devices, thiab Applications)
Daim duab 3 Kev sib piv ntawm ntau kauj ruam zog ion implantation thiab wafer nto doping concentration faib
(Source: G.Lulli, Introduction To Ion Implantation)
Txhawm rau kom ua tiav cov doping concentration nyob rau hauv cheeb tsam ion implantation, engineers feem ntau siv ntau kauj ruam ion implantation los kho tag nrho cov concentration faib ntawm cheeb tsam implantation (raws li qhia hauv daim duab 3); nyob rau hauv cov txheej txheem tsim khoom tiag tiag, los ntawm kev kho lub zog implantation thiab implantation koob tshuaj ntawm ion implantation, doping concentration thiab doping qhov tob ntawm ion implantation cheeb tsam tuaj yeem tswj tau, raws li qhia hauv daim duab 4. (a) thiab (b); lub ion implanter ua cov ion implantation nyob rau hauv wafer nto los ntawm scanning lub wafer nto ntau zaus thaum lub sij hawm ua hauj lwm, raws li qhia nyob rau hauv daim duab 4. (c).
(c) Kev txav mus los ntawm ion implanter thaum lub sij hawm ion implantation
Daim duab 4 Thaum lub sij hawm ion implantation txheej txheem, lub impurity concentration thiab qhov tob yog tswj los ntawm kev kho cov ion implantation zog thiab koob tshuaj.
III
Ua kom cov txheej txheem annealing rau silicon carbide ion implantation
Lub concentration, faib cheeb tsam, ua kom tus nqi, tsis xws luag nyob rau hauv lub cev thiab nyob rau saum npoo ntawm lub ion implantation yog lub ntsiab tsis ntawm cov txheej txheem ion implantation. Muaj ntau yam uas cuam tshuam rau cov txiaj ntsig ntawm cov kev txwv no, suav nrog kev cog qoob loo, lub zog, siv lead ua orientation ntawm cov khoom siv, qhov kub thiab txias, qhov kub thiab txias annealing, lub sijhawm annealing, ib puag ncig, thiab lwm yam. Cov impurities ntawm silicon carbide tom qab ion implantation doping. Noj cov txhuas txais ionization tus nqi nyob rau hauv nruab nrab cheeb tsam ntawm 4H-SiC ua piv txwv, ntawm ib tug doping concentration ntawm 1 × 1017cm-3, tus txais ionization tus nqi tsuas yog hais txog 15% nyob rau hauv chav tsev kub (feem ntau ionization tus nqi ntawm silicon yog kwv yees li ntawm 100%). Txhawm rau kom ua tiav lub hom phiaj ntawm kev ua kom siab thiab tsawg dua qhov tsis xws luag, cov txheej txheem kub-kub annealing yuav raug siv tom qab ion implantation kom recrystallize lub amorphous defects generated thaum implantation, thiaj li hais tias cov implanted atoms nkag mus rau hauv lub chaw hloov chaw thiab qhib, raws li qhia. nyob rau hauv daim duab 5. Tam sim no, tib neeg txoj kev nkag siab ntawm lub tshuab ntawm cov txheej txheem annealing tseem txwv. Kev tswj hwm thiab kev nkag siab tob tob ntawm cov txheej txheem annealing yog ib qho ntawm cov kev tshawb fawb tsom ntawm ion implantation yav tom ntej.
Daim duab 5 Schematic daim duab ntawm lub atomic kev hloov pauv ntawm qhov chaw ntawm silicon carbide ion implantation cheeb tsam ua ntej thiab tom qab ion implantation annealing, qhov twg Vsisawv cev rau silicon vacancy, VCsawv cev rau carbon vacancy, Cisawv cev rau carbon filling atoms, thiab Siisawv cev rau silicon filling atoms
Ion activation annealing feem ntau suav nrog rau qhov cub annealing, ceev annealing thiab laser annealing. Vim lub sublimation ntawm Si atoms nyob rau hauv cov ntaub ntawv SiC, lub annealing kub feem ntau tsis tshaj 1800 ℃; lub annealing cua feem ntau yog nqa tawm nyob rau hauv ib tug inert roj los yog lub tshuab nqus tsev vacuum. Cov ions sib txawv ua rau cov chaw sib txawv hauv SiC thiab xav tau qhov sib txawv annealing kub. Los ntawm cov txiaj ntsig kev sim feem ntau, nws tuaj yeem txiav txim siab tias qhov kub ntawm qhov annealing ntau dua, qhov ua kom siab dua (raws li pom hauv daim duab 6).
Daim duab 6 Qhov cuam tshuam ntawm qhov kub thiab txias ntawm qhov hluav taws xob ua kom muaj zog ntawm nitrogen lossis phosphorus implantation hauv SiC (ntawm chav tsev kub)
(tag nrho implantation koob tshuaj 1 × 1014cm-2)
(Source: Kimoto, Cooper, Fundamentals of Silicon Carbide Technology: Loj hlob, Cwj Pwm, Devices, thiab Applications)
Cov txheej txheem nquag siv los ua kom cov txheej txheem tom qab SiC ion implantation yog nqa tawm hauv qhov chaw Ar ntawm 1600 ℃ ~ 1700 ℃ kom recrystallize SiC nto thiab qhib lub dopant, yog li txhim kho cov conductivity ntawm doped cheeb tsam; ua ntej annealing, ib txheej ntawm carbon zaj duab xis tuaj yeem coated rau ntawm wafer nto rau saum npoo tiv thaiv kom tsis txhob degradation ntawm desorption los ntawm Si desorption thiab nto atomic migration, raws li qhia hauv daim duab 7; Tom qab annealing, cov yeeb yaj kiab carbon tuaj yeem raug tshem tawm los ntawm oxidation lossis corrosion.
Daim duab 7 Kev sib piv ntawm qhov roughness ntawm 4H-SiC wafers nrog los yog tsis muaj carbon zaj duab xis tiv thaiv nyob rau hauv 1800 ℃ annealing kub
(Source: Kimoto, Cooper, Fundamentals of Silicon Carbide Technology: Loj hlob, Cwj Pwm, Devices, thiab Applications)
IV
Qhov cuam tshuam ntawm SiC ion implantation thiab activation annealing txheej txheem
Ion implantation thiab tom qab ua kom cov annealing yuav inevitably tsim cov teeb meem uas txo cov kev ua tau zoo ntawm cov cuab yeej: complex point defects, stacking faults (raws li qhia nyob rau hauv daim duab 8), dislocations tshiab, ntiav los yog sib sib zog nqus theem defects, basal dav hlau dislocation loops thiab txav ntawm cov dislocations uas twb muaj lawm. Txij li cov txheej txheem siab-zog ion foob pob tawg yuav ua rau muaj kev ntxhov siab rau SiC wafer, cov txheej txheem kub thiab lub zog ion implantation siab yuav ua rau cov wafer warpage. Cov teeb meem no kuj tau dhau los ua cov kev taw qhia uas yuav tsum tau kho kom zoo thiab kawm hauv cov txheej txheem tsim khoom ntawm SiC ion implantation thiab annealing.
Daim duab 8 Schematic daim duab ntawm kev sib piv ntawm ib txwm 4H-SiC lattice kev npaj thiab sib txawv stacking txhaum
(Source: Nicolὸ Piluso 4H-SiC Defects)
V.
Kev txhim kho ntawm silicon carbide ion implantation txheej txheem
(1) Ib zaj duab xis oxide nyias yog khaws cia rau ntawm qhov chaw ntawm ion implantation kom txo tau qhov kev puas tsuaj ntawm cov implantation los ntawm high-zog ion implantation rau saum npoo ntawm silicon carbide epitaxial txheej, raws li qhia hauv daim duab 9. (a) .
(2) Txhim kho qhov zoo ntawm lub hom phiaj disk hauv cov khoom siv ion implantation, kom lub wafer thiab lub hom phiaj disk haum zoo dua, thermal conductivity ntawm lub hom phiaj disk rau wafer zoo dua, thiab cov cuab yeej ua kom sov sab nraum qab ntawm lub wafer. ntau uniformly, txhim kho qhov zoo ntawm high-temperature thiab high-zog ion implantation ntawm silicon carbide wafers, raws li qhia nyob rau hauv daim duab 9. (b).
(3) Ua kom zoo tshaj qhov kub thiab txias qhov sib xws thaum lub sijhawm ua haujlwm ntawm cov khoom siv kub-kub annealing.
Daim duab 9 Txoj kev txhim kho ion implantation txheej txheem
Post lub sij hawm: Oct-22-2024