Njira zazikulu zokulitsira silicon carbide single crystals ndi monga Physical Vapor Transport (PVT), Top-Seeded Solution Growth (TSSG), ndi High-Temperature Chemical Vapor Deposition (HT-CVD).

Mwa izi, njira ya PVT yakhala njira yoyamba yopangira mafakitale chifukwa cha kukhazikitsidwa kwake kosavuta kwa zida, kugwiritsa ntchito mosavuta ndikuwongolera, komanso kutsika kwa zida ndi ndalama zogwirira ntchito.

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Mfundo Zaumisiri Zofunikira za Kukula kwa SiC Crystal Pogwiritsa Ntchito Njira ya PVT

Kukulitsa makhiristo a silicon carbide pogwiritsa ntchito njira ya PVT, mbali zingapo zaukadaulo ziyenera kuyang'aniridwa mosamala:

1. Kuyera kwa Zida za Graphite mu Thermal Field
   Zida za graphite zomwe zimagwiritsidwa ntchito m'munda wotentha wa kristalo ziyenera kukwaniritsa zofunikira zachiyero. Zomwe zili zonyansa mu zigawo za graphite ziyenera kukhala pansi pa 5 × 10⁻⁶, ndi zotsekemera zotsekemera pansi pa 10 × 10⁻⁶. Makamaka, zomwe zili mu boron (B) ndi aluminiyamu (Al) ziyenera kukhala pansi pa 0.1×10⁻⁶.

2. Polarity Yolondola ya Seed Crystal
   Deta yamphamvu imasonyeza kuti C-face (0001) ndi yoyenera kukula kwa makristasi a 4H-SiC, pamene Si-face (0001) ndi yoyenera kukula kwa 6H-SiC.

3. Kugwiritsa Ntchito Mafuta a Off-Axis Seed
   Mbeu zakunja zimatha kusintha kukula, kuchepetsa zolakwika za kristalo, ndikulimbikitsa mtundu wabwino wa kristalo.

4. Njira Yodalirika ya Mbewu ya Crystal Bonding
   Kugwirizana koyenera pakati pa kristalo wa mbewu ndi mwiniwake ndikofunikira kuti pakhale bata pakukula.

5. Kusunga Kukhazikika kwa Chiyankhulo cha Kukula
   Panthawi yonse ya kukula kwa kristalo, mawonekedwe a kukula ayenera kukhala okhazikika kuti atsimikizire chitukuko chapamwamba cha kristalo.

 

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Core Technologies mu Kukula kwa SiC Crystal

1. Doping Technology ya SiC Powder

Doping SiC ufa ndi cerium (Ce) akhoza kukhazikika kukula kwa polytype imodzi monga 4H-SiC. Zochita zawonetsa kuti Ce doping imatha:

• Wonjezerani kukula kwa makristasi a SiC;

• Kupititsa patsogolo mawonekedwe a kristalo kuti akule mofanana komanso molunjika;

• Kuchepetsa zonyansa ndi zolakwika;

• Kuletsa dzimbiri kumbuyo kwa kristalo;

• Limbikitsani kuchuluka kwa zokolola za kristalo imodzi.

2. Kuwongolera kwa Axial ndi Radial Thermal Gradients

Kutentha kwa axial kumakhudza crystal polytype ndi kukula kwake. Ma gradient omwe ali ochepa kwambiri amatha kupangitsa kuti polytype inclusions iwonongeke komanso kuchepetsedwa kwa kayendedwe ka zinthu mu gawo la nthunzi. Kuwongolera ma axial ndi ma radial gradients ndikofunikira kuti kristalo ikule mwachangu komanso mosasunthika.

3. Basal Plane Dislocation (BPD) Control Technology

Ma BPD amapangidwa makamaka chifukwa cha kumeta ubweya kupitirira malire ofunikira mu makristasi a SiC, kuyambitsa makina oterera. Popeza ma BPD ali okhazikika kumayendedwe akukulira, nthawi zambiri amawuka pakukula kwa kristalo ndi kuzizira. Kuchepetsa kupsinjika kwamkati kumatha kuchepetsa kwambiri kuchuluka kwa BPD.

4. Vapor Phase Composition Ratio Control

Kuchulukitsa kuchuluka kwa carbon-to-silicon mu gawo la nthunzi ndi njira yotsimikiziridwa yolimbikitsira kukula kwa polytype imodzi. Chiŵerengero chachikulu cha C/Si chimachepetsa macrostep bunching ndikusunga cholowa chapamwamba kuchokera ku kristalo wa mbewu, motero kuletsa mapangidwe amitundu yosafunika.

5. Njira Zokulitsa Kupsinjika Kwambiri

Kupsinjika pakukula kwa kristalo kungayambitse ndege zokhotakhota, ming'alu, komanso kuchulukira kwa BPD. Zowonongeka izi zitha kupitilira mu zigawo za epitaxial ndikusokoneza magwiridwe antchito a chipangizocho.

Njira zingapo zochepetsera kupsinjika kwa kristalo mkati ndi monga:

• Kusintha magawo a magawo otentha ndikuwongolera magawo kuti alimbikitse kukula kwapafupi;

• Kupititsa patsogolo mapangidwe a crucible kuti alole kristalo kukula momasuka popanda zopinga zamakina;

• Kupititsa patsogolo kakhazikitsidwe ka chosungira mbeu kuti muchepetse kusagwirizana kwa kukula kwa matenthedwe pakati pa njere ndi graphite panthawi yotentha, nthawi zambiri posiya kusiyana kwa 2 mm pakati pa njere ndi chosungira;

• Kuyeretsa ma annealing, kulola kristalo kuzizirira ndi ng'anjo, ndikusintha kutentha ndi nthawi kuti muchepetse kupsinjika kwamkati.

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Zochitika mu SiC Crystal Growth Technology

1. Zazikulu Za Crystal
SiC single crystal diameters yawonjezeka kuchoka pa mamilimita ochepa kufika pa 6-inchi, 8-inchi, komanso 12-inch wafers. Zophika zazikuluzikulu zimathandizira kupanga bwino ndikuchepetsa mtengo, kwinaku zikukwaniritsa zofunikira za zida zamphamvu kwambiri.

2. Ubwino Wapamwamba wa Crystal
Makristalo apamwamba a SiC ndi ofunikira pazida zogwira ntchito kwambiri. Ngakhale kusintha kwakukulu, makhiristo amakono akuwonetsabe zolakwika monga ma micropipes, dislocation, ndi zonyansa, zonse zomwe zingawononge machitidwe ndi kudalirika kwa chipangizo.

3. Kuchepetsa Mtengo
Kupanga makristalo a SiC akadali okwera mtengo, kumachepetsa kutengera kokulirapo. Kuchepetsa mtengo pogwiritsa ntchito njira zokulirapo, kuchulukirachulukira kopanga, komanso kutsika kwamitengo yamafuta ndikofunikira pakukulitsa ntchito zamsika.

4. Kupanga Mwanzeru
Ndi kupita patsogolo kwaluntha lochita kupanga komanso matekinoloje akuluakulu a data, kukula kwa kristalo wa SiC kukupita kunjira zanzeru, zongopanga zokha. Masensa ndi machitidwe owongolera amatha kuyang'anira ndikusintha mikhalidwe ya kukula munthawi yeniyeni, kuwongolera kukhazikika kwadongosolo komanso kulosera. Ma analytics a data amatha kupititsa patsogolo magawo azinthu komanso mtundu wa kristalo.

Kukula kwaukadaulo wapamwamba kwambiri wa SiC single crystal kukula ndikofunikira kwambiri pakufufuza kwa zida za semiconductor. Pamene luso lamakono likupita patsogolo, njira za kukula kwa kristalo zidzapitirizabe kusinthika ndi kusintha, ndikupereka maziko olimba a ntchito za SiC pazida zotentha kwambiri, zothamanga kwambiri, komanso zamagetsi zamagetsi.