Dasa ion hanya ce ta ƙara ƙayyadaddun adadi da nau'in ƙazanta cikin kayan semiconductor don canza kayan lantarki. Ana iya sarrafa adadin da rarraba ƙazanta daidai.
Kashi na 1
Me yasa ake amfani da tsarin dasa ion
A cikin kera na'urorin semiconductor na wutar lantarki, yankin P/N doping na gargajiyasiliki wafersza a iya samu ta hanyar yadawa. Duk da haka, yawan yaɗuwar atom ɗin ƙazanta a cikisiliki carbideyana da ƙasa sosai, don haka ba daidai ba ne don cimma zaɓin doping ta hanyar watsawa, kamar yadda aka nuna a cikin Hoto 1. A gefe guda, yanayin zafin jiki na ion implantation ya yi ƙasa da na tsarin watsawa, kuma mafi sassauƙa kuma daidaitaccen rarraba doping zai iya. a kafa.
Hoto 1 Kwatankwacin watsawa da fasahar ion implantation doping a cikin kayan silicon carbide
Kashi na 2
Yadda ake cimmawasiliki carbideion implantation
Abubuwan da aka saba amfani da su a cikin tsarin masana'antar siliki carbide na yau da kullun sun ƙunshi tushen ion, plasma, abubuwan sha'awa, maganadisu na nazari, igiyoyin ion, bututun hanzari, ɗakunan sarrafawa, da fayafai na dubawa, kamar yadda aka nuna a cikin Hoto 2.
Hoto 2 Tsarin tsari na silicon carbide babban ƙarfin ion kayan aikin dasa
(Madogararsa: "Fasahar Manufacturing Semiconductor")
SiC ion implantation yawanci ana aiwatar da shi a babban zafin jiki, wanda zai iya rage lalacewar lattice ɗin crystal wanda ion bombardment ya haifar. Domin4H-SiC wafers, samar da nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'in)) ta hanyar sanya nitrogen da ions phosphorus, da kuma samar da suNau'in PYawancin wurare ana samun su ta hanyar dasa ions aluminum da boron ions.
Tebur 1. Misalin zaɓin doping a cikin kera na'urar SiC
(Madogararsa: Kimoto, Cooper, Tushen Fasahar Silicon Carbide: Girma, Halaye, Na'urori, da Aikace-aikace)
Hoto 3 Kwatankwacin dasa ion makamashi mai matakai da yawa da rarraba abubuwan kara kuzari da wafer
(Madogararsa: G.Lulli, Gabatarwa Zuwa Dashen ion)
Domin cimma daidaiton adadin doping a cikin yankin da aka saka ion, injiniyoyi yawanci suna amfani da ion mai matakai masu yawa don daidaita yawan rarraba taro na yanki (kamar yadda aka nuna a cikin Hoto 3); a cikin ainihin tsari na masana'antu, ta hanyar daidaita ƙarfin haɓakawa da haɓakawa na ion implanter, za'a iya sarrafa ƙwayar doping da zurfin doping na yanki na ion, kamar yadda aka nuna a cikin Hoto 4. (a) da (b); ion implanter yayi daidai ion implantation a kan wafer surface ta duban wafer sau da yawa a lokacin aiki, kamar yadda aka nuna a Figure 4. (c).
(c) Yanayin motsi na ion implanter a lokacin ion implantation
Hoto 4 A lokacin tsarin dasa ion, ana sarrafa ƙaddamar da ƙazanta da zurfin ta hanyar daidaita ƙarfin dasa ion da kashi.
III
Tsarin kunnawa don shigar da siliki carbide ion
Ƙaddamarwa, yanki na rarrabawa, ƙimar kunnawa, lahani a cikin jiki da kuma saman ion implantation shine ainihin ma'auni na tsarin ion ion. Akwai abubuwa da yawa da ke shafar sakamakon waɗannan sigogi, ciki har da kashi na implantation, makamashi, crystal orientation of the material, implantation zafin jiki, annealing zafin jiki, annealing lokaci, yanayi, da dai sauransu Ba kamar silicon ion implantation doping, yana da wuya a gaba daya ionize. da datti na silicon carbide bayan ion implantation doping. Ɗaukar ƙimar ionization mai karɓar aluminum a cikin tsaka-tsakin yanki na 4H-SiC a matsayin misali, a matakin doping na 1 × 1017cm-3, ƙimar ionization mai karɓa shine kawai kusan 15% a cikin zafin jiki (yawanci ƙimar ionization na silicon kusan kusan). 100%). Don cimma burin yawan kunnawa da ƙananan lahani, za a yi amfani da tsarin cire zafin jiki mai zafi bayan dasa ion don sake haifar da lahani na amorphous da aka haifar yayin dasawa, ta yadda atom ɗin da aka dasa su shiga wurin maye gurbin kuma ana kunna su, kamar yadda aka nuna. a cikin Hoto na 5. A halin yanzu, fahimtar mutane game da tsarin aikin cirewa yana da iyaka. Sarrafa da zurfin fahimtar tsarin cirewa yana ɗaya daga cikin abubuwan da aka mayar da hankali kan bincike na dasa ion a nan gaba.
Hoto 5 Tsarin tsari na tsarin atomic yana canzawa a saman wurin dasa shuki na silicon carbide ion kafin da kuma bayan shigar da ion, inda V.siwakiltar guraben silicon, VCyana wakiltar guraben carbon, Ciyana wakiltar zarra masu cika carbon, da Siiyana wakiltar zarra masu cika siliki
Ion kunnawa annealing gabaɗaya ya haɗa da murɗa tanderu, saurin ɓarnawa da cirewar laser. Saboda girman girman Si atom a cikin kayan SiC, yanayin zafi gabaɗaya baya wuce 1800 ℃; yanayin daɗaɗɗen yanayi gabaɗaya ana aiwatar da shi ne a cikin iskar da ba ta da ƙarfi ko kuma mara amfani. Ions daban-daban suna haifar da cibiyoyin lahani daban-daban a cikin SiC kuma suna buƙatar yanayin zafi daban-daban. Daga mafi yawan sakamakon gwaji, ana iya ƙarasa da cewa mafi girman zafin jiki na annealing, mafi girman ƙimar kunnawa (kamar yadda aka nuna a cikin Hoto 6).
Hoto 6 Tasirin zafin zafin jiki akan ƙimar kunna wutar lantarki na nitrogen ko phosphorus dasa a cikin SiC (a dakin zafin jiki)
(Jimlar kashi 1 × 1014cm-2)
(Madogararsa: Kimoto, Cooper, Tushen Fasahar Silicon Carbide: Girma, Halaye, Na'urori, da Aikace-aikace)
Annealing na kunnawa da aka saba amfani da shi bayan shigar da SiC ion ana aiwatar da shi a cikin yanayin Ar a 1600 ℃ ~ 1700 ℃ don sake sake fasalin SiC da kunna dopant, ta haka inganta haɓakar yankin doped; kafin anealing, wani Layer na carbon film za a iya mai rufi a kan wafer surface for surface kariya don rage surface lalacewa lalacewa ta hanyar Si desorption da surface atomic hijirarsa, kamar yadda aka nuna a cikin Figure 7; bayan annealing, ana iya cire fim ɗin carbon ta hanyar iskar shaka ko lalata.
Hoto 7 Kwatankwacin rashin ƙarfi na 4H-SiC wafers tare da ko ba tare da kariyar fim ɗin carbon ƙarƙashin 1800 ℃ annealing zafin jiki
(Madogararsa: Kimoto, Cooper, Tushen Fasahar Silicon Carbide: Girma, Halaye, Na'urori, da Aikace-aikace)
IV
Tasirin shigar da SiC ion da aiwatar da aikin annealing
Shigarwa na ion da kunnawa na gaba zai haifar da lahani wanda zai rage aikin na'urar: hadaddun lahani, kurakuran da aka nuna (kamar yadda aka nuna a cikin hoto 8), sababbin rarrabuwa, ƙarancin matakin makamashi mai zurfi ko zurfi, madaukai na rushewar jirgin sama da motsi na tarwatsawa. Tun da babban tsarin bam na ion mai ƙarfi zai haifar da damuwa ga wafer SiC, babban zafin jiki da haɓakar ion mai ƙarfi zai ƙara yawan wafer warpage. Waɗannan matsalolin kuma sun zama alƙawarin da ke buƙatar ingantawa da kuma yin nazari cikin gaggawa a cikin tsarin masana'antu na saka SiC ion da cirewa.
Hoto 8 Tsarin tsari na kwatancen tsakanin tsarin lattice na 4H-SiC na yau da kullun da kurakuran tari daban-daban
(Madogararsa: Nicolὸ Piluso 4H-SiC Defections)
V.
Inganta tsarin dasa shuki na siliki carbide
(1) Ana ajiye fim din oxide na bakin ciki a saman filin da aka sanya ion don rage girman lalacewar da aka samu ta hanyar haɓakar makamashi mai girma zuwa saman silin carbide epitaxial Layer, kamar yadda aka nuna a cikin Hoto 9. (a) .
(2) Inganta ingancin faifan manufa a cikin na'urorin dasa ion, ta yadda wafer da faifan manufa sun dace sosai, yanayin zafi na faifan manufa zuwa wafer ya fi kyau, kuma kayan aikin suna dumama bayan wafer. mafi daidaituwa, inganta ingancin yanayin zafi mai zafi da haɓakar ion mai ƙarfi a kan wafers na silicon carbide, kamar yadda aka nuna a cikin Hoto 9. (b).
(3) Haɓaka ƙimar haɓakar zafin jiki da daidaiton zafin jiki yayin aiki na kayan zafi mai zafi.
Hoto na 9 Hanyoyi don inganta tsarin dasa ion
Lokacin aikawa: Oktoba-22-2024