The core fasaha ga girma naSiC epitaxialkayan aikin fasaha ne na sarrafa lahani na farko, musamman don fasahar sarrafa lahani waɗanda ke da saurin gazawar na'urar ko lalata amincin. Nazarin tsarin na'urorin da ke haɓakawa zuwa cikin epitaxial Layer a lokacin tsarin ci gaban epitaxial, canja wurin da dokokin canji na lahani a tsaka-tsakin tsaka-tsaki da epitaxial Layer, da kuma tsarin ƙaddamarwa na lahani shine tushen don bayyana alaƙa tsakanin lahani na substrate da lahani na tsarin epitaxial, wanda zai iya jagorance ta yadda ya kamata don tantancewa da inganta tsarin epitaxial.
LalacewarSilica carbide epitaxial yaduddukaAn fi raba su zuwa nau'i biyu: lahani na crystal da lahani na ilimin halittar jiki. Lalacewar kristal, gami da lahani mai ma'ana, ɓarkewar dunƙulewa, lahani na microtubule, ɓarke gefe, da sauransu, galibi sun samo asali ne daga lahani akan sifofin SiC kuma suna yadawa cikin Layer epitaxial. Ana iya lura da lahani na zahiri da ido kai tsaye tare da ido tsirara ta amfani da na'urar gani da ido kuma suna da halaye na musamman. Lalacewar ilimin halittar jiki musamman sun haɗa da: Scratch, Lalacewar Triangular, Lalacewar Karas, Faɗuwar ƙasa, da Barbashi, kamar yadda aka nuna a cikin Hoto na 4. A yayin aikin epitaxial, ɓarna na waje, lahani na substrate, lalacewar ƙasa, da karkatar da tsarin epitaxial na iya shafar duk matakan matakai na gida. yanayin girma, yana haifar da lahani na sararin samaniya.
Tebur 1. Abubuwan da ke haifar da samuwar lahani na matrix na gama gari da lahani na ilimin halittar jiki a cikin SiC epitaxial layers
Lalacewar maki
Ana samun lahani ta hanyar guraben aiki ko gibi a wuri guda ɗaya ko maki da yawa, kuma ba su da ƙarin sarari. Lalacewar maki na iya faruwa a kowane tsari na samarwa, musamman a cikin shigar da ion. Duk da haka, suna da wuyar ganowa, kuma dangantakar da ke tsakanin canji na lahani da sauran lahani yana da wuyar gaske.
Micropipe (MP)
Micropipes su ne ɓarkewar dunƙulewa waɗanda ke yaduwa tare da axis girma, tare da vector Burgers <0001>. Diamita na microtubes yana daga juzu'in micron zuwa dubun microns. Microtubes suna nuna manyan fasalulluka masu kama da rami akan saman wafers na SiC. Yawanci, yawancin microtubes shine game da 0.1 ~ 1cm-2 kuma yana ci gaba da raguwa a cikin saka idanu na samar da wafer na kasuwanci.
Screw dislocations (TSD) da dislocations gefen (TED)
Rarrabuwa a cikin SiC shine babban tushen lalacewar na'urar da gazawar. Dukansu raguwa (TSD) da ɓarkewar gefen (TED) suna gudana tare da axis girma, tare da burgers vectors na <0001> da 1/3 <11-20>, bi da bi.
Dukansu screw dislocations (TSD) da dislocations gefen (TED) na iya haɓakawa daga ƙasa zuwa farfajiyar wafer kuma suna kawo ƙananan siffofi kamar rami (Hoto 4b). Yawanci, yawan ɓarkewar gefuna yana kusan sau 10 na ɓarkewar dunƙulewa. Ƙwaƙwalwar dunƙulewar dunƙulewa, wato, wanda ya tashi daga ƙasa zuwa epilayer, na iya canzawa zuwa wasu lahani da yaduwa tare da axis girma. A lokacinSiC epitaxialgirma, dunƙule dislocations suna tuba zuwa stacking kurakurai (SF) ko karas lahani, yayin da gefen dislocations a epilayers aka nuna da za a tuba daga basal jirgin dislocations (BPDs) gada daga substrate a lokacin epitaxial girma.
Ragewar jirgin sama na asali (BPD)
An samo shi akan jirgin saman SiC basal, tare da vector Burgers na 1/3 <11-20>. BPDs ba safai suke fitowa a saman wafers na SiC. Yawancin lokaci suna mayar da hankali kan substrate tare da nauyin 1500 cm-2, yayin da yawancin su a cikin epilayer shine kawai 10 cm-2. Gano BPDs ta amfani da photoluminescence (PL) yana nuna fasalin layi, kamar yadda aka nuna a Hoto 4c. A lokacinSiC epitaxialgirma, ƙarin BPDs na iya canzawa zuwa kuskuren stacking (SF) ko dislocations gefen (TED).
Laifin tarawa (SFs)
Rashin lahani a cikin jeri-jere na jirgin basal na SiC. Matsaloli na iya bayyana a cikin epitaxial Layer ta hanyar gadon SFs a cikin ma'auni, ko kuma suna da alaƙa da tsawo da kuma canzawa na basal jirgin sama dislocations (BPDs) da threading dunƙule dislocations (TSDs). Gabaɗaya, yawancin SFs bai wuce 1 cm-2 ba, kuma suna nuna fasalin triangular lokacin da aka gano ta amfani da PL, kamar yadda aka nuna a cikin Hoto 4e. Koyaya, ana iya samun nau'ikan kurakuran tari iri-iri a cikin SiC, kamar nau'in Shockley da nau'in Frank, saboda ko da ƙaramin adadin kuzarin kuzari tsakanin jiragen sama na iya haifar da babban rashin daidaituwa a cikin jeri.
Faduwa
A downfall lahani yafi samo asali daga barbashi drop a kan babba da kuma gefen ganuwar da dauki jam'iyya a lokacin girma tsari, wanda za a iya inganta ta optimizing da lokaci-lokaci tabbatarwa aiwatar da dauki jam'iyya graphite consumables.
Lalacewar triangular
Haɗin nau'in nau'in nau'in nau'in nau'in nau'in nau'in 3C-SiC ne wanda ya shimfiɗa zuwa saman SiC epilayer tare da jagorar jirgin basal, kamar yadda aka nuna a Hoto 4g. Za a iya haifar da shi ta hanyar faɗuwar barbashi a saman SiC epilayer yayin girma na epitaxial. Abubuwan da aka saka a cikin epilayer kuma suna tsoma baki tare da tsarin girma, wanda ya haifar da 3C-SiC polytype inclusions, wanda ke nuna siffofi masu kaifi-angle mai siffar triangular tare da barbashi da ke a ƙarshen yanki na triangular. Yawancin karatu sun kuma danganta asalin polytypions zuwa ga karce na saman, micropipes, da sigogin da basu dace ba na aikin ci gaban.
Lalacewar karas
Lalacewar karas wani hadadden laifi ne mai tari mai tsayi biyu da ke cikin jiragen TSD da SF basal crystal, wanda aka ƙare ta hanyar ɓarna irin ta Frank, kuma girman lahanin karas yana da alaƙa da kuskuren stacking prismatic. Haɗuwar waɗannan fasalulluka suna haifar da yanayin yanayin yanayin lalacewar karas, wanda yayi kama da siffar karas tare da ƙarancin ƙasa da 1 cm-2, kamar yadda aka nuna a hoto na 4f. Lalacewar karas ana samun sauƙin samu ta goge goge, TSDs, ko lahani.
Scratches
Scratches lahani ne na inji akan saman wafers na SiC da aka kafa yayin aikin samarwa, kamar yadda aka nuna a Hoto 4h. Scratches a kan ma'auni na SiC na iya tsoma baki tare da girma na epilayer, samar da jeri na babban mawuyaci a cikin epilayer, ko karce na iya zama tushen samuwar lahani na karas. Sabili da haka, yana da mahimmanci don goge SiC wafers da kyau saboda waɗannan karce na iya yin tasiri mai mahimmanci akan aikin na'urar lokacin da suka bayyana a wurin aiki na na'urar.
Sauran lahani na yanayin halittar jiki
Bunching mataki wani lahani ne na saman da aka kafa a lokacin tsarin ci gaban SiC na epitaxial, wanda ke samar da triangles na obtuse ko siffofi na trapezoidal akan saman SiC epilayer. Akwai sauran lahani da yawa, kamar ramukan saman ƙasa, kumbura da tabo. Waɗannan lahani yawanci ana haifar da su ta rashin ingantaccen tsarin haɓakawa da rashin cikar cire lalacewar goge baki, wanda ke yin illa ga aikin na'urar.
Lokacin aikawa: Juni-05-2024