Hot filament CVD ndiye njira yakale komanso yotchuka kwambiri yokulitsira diamondi pamagetsi otsika. 1982 Matsumoto et al. Anatenthetsa chingwe chachitsulo chosakanizika kupitirira 2000 ° C, pomwe kutentha kwa mpweya wa H2 wodutsa mu ulusiwu umapanga maatomu a haidrojeni mosavuta. Kupanga kwa atomiki wa haidrojeni pa hydrocarbon pyrolysis kumawonjezera kuchuluka kwa mafilimu a diamondi. Daimondi imayikidwa mwachisawawa ndipo mapangidwe a graphite amaletsedwa, zomwe zimapangitsa kuti filimu ya diamondi iwonetsedwe motsatira ndondomeko ya mm / h, yomwe ndi chiwerengero chapamwamba kwambiri cha njira zomwe zimagwiritsidwa ntchito m'makampani. HFCVD imatha kuchitidwa pogwiritsa ntchito mitundu yosiyanasiyana ya mpweya, monga methane, propane, acetylene, ndi ma hydrocarbons ena, komanso ma hydrocarbons okhala ndi okosijeni, monga acetone, ethanol, ndi methanol. Kuphatikizika kwa magulu okhala ndi okosijeni kumakulitsa kutentha kwa diamondi.
Kuphatikiza pa machitidwe wamba a HFCVD, pali zosintha zingapo pamakina a HFCVD. Chofala kwambiri ndi kuphatikiza DC plasma ndi HFCVD system. Mu dongosolo lino, voteji kukondera angagwiritsidwe ntchito pa gawo lapansi ndi filament. Kukondera kosalekeza kwa gawo lapansi ndi kukondera kwina koyipa kwa ulusi kumapangitsa ma elekitironi kuphulitsa gawo lapansi, kulola kuti haidrojeni padziko lapansi iwonongeke. Zotsatira za desorption ndikuwonjezeka kwa kuchuluka kwa filimu ya diamondi (pafupifupi 10 mm / h), njira yotchedwa electron-assisted HFCVD. pamene voteji kukondera ndi mkulu mokwanira kulenga khola plasma kukhetsa, kuwonongeka kwa H2 ndi ma hydrocarbons kumawonjezeka kwambiri, zomwe pamapeto pake zimabweretsa kuwonjezeka kwa kukula. Pamene polarity ya kukondera isinthidwa (gawo lapansi liri ndi tsankho molakwika), bombardment ya ayoni imachitika pagawo laling'ono, zomwe zimapangitsa kuti ma nucleation a diamondi achuluke pamagawo osakhala a diamondi. kusinthidwa kwina ndi m'malo limodzi filament otentha ndi filaments angapo osiyanasiyana kuti tikwaniritse mafunsidwe yunifolomu ndipo pamapeto pake dera lalikulu la diamondi film.The kuipa kwa HFCVD ndi kuti matenthedwe evaporation wa filament akhoza kupanga zoipitsa mu filimu diamondi.
(2) Microwave Plasma CVD (MWCVD)
M'zaka za m'ma 1970, asayansi adapeza kuti kuchuluka kwa atomiki wa hydrogen kumatha kuonjezedwa pogwiritsa ntchito madzi a m'magazi a DC. Zotsatira zake, madzi a m'magazi anakhala njira ina yolimbikitsira kupanga mafilimu a diamondi mwa kuwola H2 kukhala atomiki haidrojeni ndi kuyambitsa magulu a atomiki a carbon. Kuphatikiza pa plasma ya DC, mitundu ina iwiri ya plasma yalandiranso chidwi. The mayikirowevu plasma CVD ali ndi mafunde pafupipafupi 2.45 GHZ, ndi RF plasma CVD ali ndi mafunde pafupipafupi 13.56 MHz. Ma plasma a microwave ndi apadera chifukwa ma frequency a microwave amapangitsa kugwedezeka kwa ma elekitironi. Ma electron akawombana ndi maatomu a gasi kapena mamolekyu, mlingo waukulu wa dissociation umapangidwa. Madzi a m'madzi a Microwave nthawi zambiri amatchedwa nkhani yokhala ndi ma elekitironi "otentha", ma ion "ozizira" ndi tinthu tating'onoting'ono. Pakuyika filimu yopyapyala, ma microwave amalowa m'chipinda cha CVD chowonjezera cha plasma kudzera pawindo. Plasma yowala nthawi zambiri imakhala yozungulira, ndipo kukula kwa gawolo kumawonjezeka ndi mphamvu ya microwave. Mafilimu opyapyala a diamondi amakula pagawo laling'ono pakona ya dera lowala, ndipo gawo lapansi siliyenera kukhudzana mwachindunji ndi dera lowala.
-Nkhaniyi yatulutsidwa ndiwopanga makina opangira vacuumGuangdong Zhenhua
Nthawi yotumiza: Jun-19-2024