Chii chinonzi CVD SiC Coating?
Chemical vapor deposition (CVD) ivacuum deposition process inoshandiswa kugadzira yakakwirira-kuchena yakasimba zvinhu. Iyi nzira inowanzo shandiswa mumunda wekugadzira semiconductor kugadzira mafirimu akatetepa pamusoro pemawafers. Mukugadzira silicon carbide neCVD, iyo substrate inoratidzwa kune imwe kana kupfuura inovhuvhuta precursors, iyo inobata makemikari pamusoro peiyo substrate kuisa inodiwa silicon carbide deposits. Pakati penzira dzakawanda dzekugadzira silicon carbide zvinhu, zvigadzirwa zvakagadzirirwa nemakemikari vapor deposition zvine yakakwirira kufanana uye kuchena, uye iyi nzira ine yakasimba process controllability. CVD silicon carbide zvinhu zvine musanganiswa wakasarudzika weakanakisa ekupisa, magetsi uye makemikari zvivakwa, zvichiita kuti zvinyatsokodzera kushandiswa muindasitiri yesemiconductor uko kunodiwa zvemhando yepamusoro. CVD silicon carbide components anoshandiswa zvakanyanya mu etching midziyo, MOCVD midziyo, Si epitaxial midziyo uye SiC epitaxial midziyo, nokukurumidza thermal processing equipment uye mamwe minda.
Ichi chinyorwa chinotarisa pakuongorora kunaka kwemafirimu matete akakura pamhando dzakasiyana dzekushisa panguva yekugadziriraCVD SiC coating, kuitira kuti usarudze tembiricha yakakodzera yemaitiro. Chiyedzo chinoshandisa graphite seyo substrate uye trichloromethylsilane (MTS) semhinduro sosi gasi. Iyo SiC coating inoiswa neyakaderera-kudzvanywa CVD maitiro, uye iyo micromorphology yeCVD SiC coatinginocherechedzwa nekuongorora electron microscopy kuti iongorore kusimba kwayo kwemaitiro.
Nekuda kwekuti tembiricha yepasi yegraphite substrate yakakwira zvakanyanya, gasi repakati richabviswa uye kuburitswa kubva kune substrate pamusoro, uye pakupedzisira iyo C uye Si inosara pane substrate pamusoro inoumba yakasimba chikamu SiC kuita SiC coating. Zvinoenderana neiyo iri pamusoro CVD-SiC yekukura maitiro, zvinogona kuoneka kuti tembiricha ichakanganisa kupararira kwegasi, kuparara kweMTS, kuumbwa kwemadonhwe uye desorption uye kubuda kwegasi repakati, saka tembiricha yekuisa ichaita basa rakakosha mumorphology yeSiC coating. Iyo microscopic morphology yejasi ndiyo yakanyanya intuitive kuratidzwa kwe density yejasi. Naizvozvo, zvinodikanwa kuti udzidze mhedzisiro yeakasiyana deposition tembiricha pane microscopic morphology yeCVD SiC coating. Sezvo MTS ichigona kuora uye kuisa SiC coating pakati pe900 ~ 1600 ℃, kuedza uku kunosarudza shanu deposition tembiricha ye900 ℃, 1000 ℃, 1100 ℃, 1200 ℃ uye 1300 ℃ kugadzirira SiC coating kuti idzidze mhedzisiro yetembiricha yeCVD pacoating. Iwo chaiwo maparamendi anoratidzwa muTafura 3. Mufananidzo 2 unoratidza microscopic morphology yeCVD-SiC coating inokura pane dzakasiyana deposition tembiricha.
Kana tembiricha yekuisa iri 900 ℃, ese SiC inokura kuita fiber maumbirwo. Zvinogona kuonekwa kuti dhayamita yefiber imwe chete inenge 3.5μm, uye chikamu chayo chinenge 3 (<10). Uyezve, inoumbwa neasingaverengeki nano-SiC particles, saka ndeye polycrystalline SiC chimiro, iyo yakasiyana neyechinyakare SiC nanowires uye imwe-crystal SiC ndebvu. Iyi fibrous SiC chirema chechimiro chinokonzerwa neasina musoro maitiro paramita. Zvinogona kuonekwa kuti chimiro cheiyi SiC coating chakasununguka, uye kune nhamba huru ye pores pakati pe fibrous SiC, uye density yakaderera zvikuru. Naizvozvo, tembiricha iyi haina kukodzera kugadzirira dense SiC coatings. Kazhinji, fibrous SiC structural defects inokonzereswa nekudzikira deposition tembiricha. Pakudziya kwakadzikira, mamorekuru madiki anoshambadzirwa pamusoro peiyo substrate ane simba rakaderera uye kusagona kutama. Naizvozvo, mamorekuru madiki anowanzo kutama uye kukura kusvika kune yakaderera pamusoro pemahara simba reSiC tsanga (senge pamuromo wezviyo). Kuenderera mberi kwekukura kunopedzisira kwaita fibrous SiC maitiro akaremara.
Kugadzirira kweCVD SiC Coating:
Chekutanga, iyo graphite substrate inoiswa muchoto chepamusoro-soro uye inochengetwa pa1500 ℃ kwe1h muAr atmosphere yekubvisa madota. Ipapo iyo graphite block inochekwa kuita block ye 15x15x5mm, uye pamusoro peiyo graphite block inokwenenzverwa ne 1200-mesh sandpaper kubvisa mapores epamusoro anokanganisa kuiswa kweSiC. Iyo yakabatwa graphite block inoshambidzwa neanhydrous ethanol uye distilled mvura, yozoiswa muovheni pa100 ℃ yekuomeswa. Chekupedzisira, iyo graphite substrate inoiswa munzvimbo huru yekushisa ye tubular choto cheSiC deposition. Iyo schematic dhizaini yemakemikari vapor deposition system inoratidzwa muMufananidzo 1.
TheCVD SiC coatingyakacherechedzwa nekuongorora electron microscopy kuti iongorore saizi yaro uye density. Uye zvakare, iyo deposition rate yeSiC coating yakaverengerwa zvinoenderana nepazasi formula: VSiC=(m2-m1)/(Sxt)x100% VSiC=Deposition rate; m2-hukuru hwekuputira sampuli (mg); m1 - kuwanda kweiyo substrate (mg); S-pamusoro penzvimbo ye substrate (mm2); t-nguva yekuisa (h). CVD-SiC yakaoma, uye maitiro anogona kupfupikiswa sezvinotevera: pakupisa kwepamusoro, MTS inozoora kupisa kuumba kabhoni sosi uye silicon sosi mamorekuru madiki. Iyo kabhoni sosi mamorekuru madiki anonyanya kusanganisira CH3, C2H2 uye C2H4, uye iyo silicon sosi mamorekuru madiki anonyanya kusanganisira SiCI2, SiCI3, nezvimwewo; aya kabhoni sosi uye silicon sosi mamorekuru madiki anozoendeswa pamusoro peiyo graphite substrate neanotakura gasi uye diluent gasi, uye ipapo aya mamorekuru madiki anozoshambadzirwa pamusoro peiyo substrate nenzira yeadsorption, uye ipapo kemikari inoitika pakati pemamorekuru madiki kuita madonhwe madiki anozokura zvishoma nezvishoma, uye madonhwe anozokura zvishoma nezvishoma. zvepakati by-zvigadzirwa (HCl gasi); Kana tembiricha yakwira kusvika 1000 ℃, density yeSiC coating inovandudzwa zvakanyanya. Zvinogona kuonekwa kuti yakawanda yekuputira inoumbwa neSiC zviyo (inenge 4μm muhukuru), asi mamwe mafivha eSiC akaremara anowanikwawo, izvo zvinoratidza kuti kuchine nzira yekukura kweSiC pane ino tembiricha, uye kupfekedza kuchiri kusati kwanyanya kukwana. Kana tembiricha yakwira kusvika 1100 ℃, zvinogona kuoneka kuti iyo SiC coating yakanyanya kusimba, uye fibrous SiC hurema hwakanyangarika zvachose. Iyo yekupfekedza inoumbwa nemadonhwe-akaita SiC particles ane dhayamita inosvika 5 ~ 10μm, ayo akanyatsobatanidzwa. Kumusoro kwezvimedu kwakanyanyisa. Inoumbwa neasingaverengeki nano-scale SiC zviyo. Muchokwadi, iyo CVD-SiC yekukura maitiro pa1100 ℃ yave kuwanda kutamiswa kunodzorwa. Mamorekuru madiki adsorbed pamusoro pe substrate ane simba rakakwana uye nguva yekuisa nucleate uye kukura kuita SiC tsanga. Mbeu dzeSiC dzakafanana dzinoumba madonhwe makuru. Pasi pekuita kwesimba repamusoro, mazhinji emadonhwe anoratidzika sedenderedzwa, uye madonhwe akanyatsobatanidzwa kuti aumbe dense SiC coating. Kana tembiricha yakwira kusvika 1200 ℃, iyo SiC coating zvakare yakakora, asi iyo SiC morphology inova yakawanda-yakaomeswa uye pamusoro peiyo coating inoratidzika rougher. Kana tembiricha ikawedzera kusvika 1300 ℃, nhamba huru yenguva dzose spherical particles ine dhayamita ingangoita 3μm inowanikwa pamusoro peiyo graphite substrate. Izvi zvinodaro nekuti panguva iyi tembiricha, SiC yakashandurwa kuita gasi chikamu nucleation, uye iyo MTS decomposition rate inokurumidza. Mamorekuru madiki akaita uye nucleated kuumba SiC zviyo zvisati zvave adsorbed pane substrate pamusoro. Mushure mekunge zviyo zvaita spherical particles, zvinowira pazasi, zvichizoguma zvaita yakasununguka SiC particle coating ine hurombo density. Zviripachena, 1300 ℃ haigone kushandiswa seyekugadzira tembiricha yedense SiC coating. Kuenzanisa kwakazara kunoratidza kuti kana dense SiC coating ichizogadzirirwa, iyo yakakwana CVD deposition tembiricha i1100 ℃.
Mufananidzo 3 unoratidza mwero wekuisa weCVD SiC coatings pane akasiyana deposition tembiricha. Sezvo tembiricha yekuisa ichiwedzera, iyo deposition rate yeSiC coating inoderera zvishoma nezvishoma. Chiyero chekuisa pa 900 ° C i 0.352 mg · h-1 / mm2, uye kukura kwakananga kwemafiber kunotungamirira kune kukurumidza kukurumidza kuisa. Chiyero chekuisa chekuvhara nehupamhi hwepamusoro ndeye 0.179 mg · h-1 / mm2. Nekuda kwekuiswa kwemamwe maSiC particles, deposition rate pa1300 ° C ndiyo yakaderera, chete 0.027 mg · h-1/mm2. Mhedziso: Iyo yakanakisa CVD deposition tembiricha ndeye 1100 ℃. Tembiricha yakaderera inosimudzira kukura kweSiC, nepo tembiricha yakakwira ichikonzera SiC kuburitsa vapor deposition uye inokonzeresa kuputira. Nekuwedzera kwekushisa kwekuisa, chiyero chekuisa cheCVD SiC coatingzvishoma nezvishoma inoderera.
Nguva yekutumira: May-26-2025