Katundu wa plasma
Mtundu wa plasma mu plasma-enhanced chemical nthunzi deposition ndi wakuti imadalira mphamvu ya kinetic ya ma elekitironi mu plasma kuti iyambe kuchitapo kanthu kwa mankhwala mu gasi. Popeza plasma ndi gulu la ma ayoni, ma elekitironi, ma atomu osalowerera ndi mamolekyu, imakhala yopanda mphamvu zamagetsi pamlingo wa macroscopic. Mu plasma, mphamvu zambiri zimasungidwa mu mphamvu yamkati ya plasma. Plasma poyamba imagawidwa mu plasma yotentha ndi plasma yozizira. Mu PECVD system ndi plasma yozizira yomwe imapangidwa ndi mpweya wochepa. Plasma iyi yopangidwa ndi mpweya wochepa wochepa pansi pa mazana angapo a Pa ndi plasma yopanda mphamvu yofanana.
Makhalidwe a plasma iyi ndi awa:
(1) Kuyenda kosasinthasintha kwa kutentha kwa ma elekitironi ndi ma ayoni kumaposa kuyenda kwawo kolunjika.
(2) Njira yake yopangira ionization imachitika makamaka chifukwa cha kugundana kwa ma elekitironi othamanga ndi mamolekyu a mpweya.
(3) Mphamvu yapakati yoyendera kutentha kwa ma elekitironi ndi yayikulu kwambiri kuyambira 1 mpaka 2 kuposa ya tinthu tolemera, monga mamolekyulu, maatomu, ma ayoni ndi ma free radicals.
(4) Kutayika kwa mphamvu pambuyo pa kugundana kwa ma elekitironi ndi tinthu tolemera kumatha kulipidwa kuchokera ku mphamvu yamagetsi pakati pa kugundana.
N'zovuta kufotokoza plasma yopanda kulinganiza kutentha kotsika yokhala ndi magawo ochepa, chifukwa ndi plasma yopanda kulinganiza kutentha kotsika mu dongosolo la PECVD, komwe kutentha kwa ma elekitironi Te sikufanana ndi kutentha kwa Tj kwa tinthu tolemera. Mu ukadaulo wa PECVD, ntchito yayikulu ya plasma ndikupanga ma ayoni ogwira ntchito mwa mankhwala ndi ma free-radicals. Ma ayoni ndi ma free-radicals amenewa amachitapo kanthu ndi ma ayoni ena, ma atomu ndi mamolekyu mu gawo la mpweya kapena kuyambitsa kuwonongeka kwa lattice ndi machitidwe a mankhwala pamwamba pa substrate, ndipo phindu la zinthu zogwira ntchito ndi ntchito ya kuchuluka kwa ma elekitironi, kuchuluka kwa reactant ndi coefficient ya yield. Mwanjira ina, phindu la zinthu zogwira ntchito limadalira mphamvu yamagetsi, kuthamanga kwa mpweya, ndi avareji yaulere ya tinthu panthawi ya kugundana. Pamene mpweya wochitapo kanthu mu plasma umalekanitsidwa chifukwa cha kugundana kwa ma elekitironi amphamvu kwambiri, chotchinga choyambitsa cha reaction ya mankhwala chikhoza kugonjetsedwa ndipo kutentha kwa mpweya wochitapo kanthu kumatha kuchepetsedwa. Kusiyana kwakukulu pakati pa PECVD ndi CVD yachizolowezi ndikuti mfundo za thermodynamic za reaction ya mankhwala ndizosiyana. Kugawanika kwa mamolekyu a mpweya mu plasma sikusankha, kotero gawo la filimu lomwe limayikidwa ndi PECVD ndi losiyana kwambiri ndi la CVD wamba. Kapangidwe ka gawo komwe kamapangidwa ndi PECVD kangakhale kosiyana ndi kamene kali kofanana, ndipo kapangidwe kake sikamachepetsedwanso ndi kinetics yofanana. Gawo lofala kwambiri la filimu ndi amorphous state.
Zinthu za PECVD
(1) Kutentha kochepa kwa malo osungiramo zinthu.
(2) Chepetsani kupsinjika kwamkati komwe kumachitika chifukwa cha kusagwirizana kwa coefficient yokulirapo ya nembanemba/maziko.
(3) Chiŵerengero cha kuyika zinthu m'mabokosi ndi chokwera kwambiri, makamaka kutentha kochepa, zomwe zimathandiza kuti mafilimu asakhale ndi mawonekedwe akunja komanso ang'onoang'ono.
Chifukwa cha kutentha kochepa kwa PECVD, kuwonongeka kwa kutentha kumatha kuchepetsedwa, kufalikira kwa mgwirizano ndi kuchitapo kanthu pakati pa gawo la filimu ndi zinthu za substrate kumatha kuchepetsedwa, ndi zina zotero, kotero kuti zida zamagetsi zitha kuphimbidwa zonse zisanapangidwe kapena chifukwa chofuna kukonzanso. Pakupanga ma ultra-large scale integrated circuits (VLSI, ULSI), ukadaulo wa PECVD umagwiritsidwa ntchito bwino popanga filimu ya silicon nitride (SiN) ngati filimu yoteteza yomaliza pambuyo pakupanga mawaya a electrode a Al, komanso kupendeketsa ndi kupanga filimu ya silicon oxide ngati insulation ya interlayer. Monga zida zopyapyala, ukadaulo wa PECVD wagwiritsidwanso ntchito bwino popanga ma transistors a thin-film (TFTs) a LCD displays, ndi zina zotero, pogwiritsa ntchito galasi ngati substrate mu njira yogwira ntchito ya matrix. Ndi chitukuko cha ma circuits ophatikizana kupita ku integration yayikulu komanso yapamwamba komanso kugwiritsa ntchito kwambiri zida za semiconductor, PECVD ikufunika kuchitidwa pa kutentha kochepa komanso njira zamagetsi apamwamba. Kuti akwaniritse izi, ukadaulo womwe ungapange mafilimu apamwamba kwambiri pa kutentha kochepa uyenera kupangidwa. Makanema a SiN ndi SiOx aphunziridwa kwambiri pogwiritsa ntchito plasma ya ECR ndi ukadaulo watsopano wa plasma chemical vapor deposition (PCVD) wokhala ndi helical plasma, ndipo afika pamlingo wothandiza pakugwiritsa ntchito mafilimu oteteza pakati pa zigawo zazikulu zolumikizidwa, ndi zina zotero.
Nthawi yotumizira: Novembala-08-2022