ʻenehana kiʻiʻoniʻoni lahilahi daimana-mokuna 1

ʻO CVD filament wela ke ala mua a kaulana loa o ka ulu daimana ma ke kaomi haʻahaʻa. 1982 Matsumoto et al. Hoʻomāhana i kahi filament metala refractory a ʻoi aku ma luna o 2000°C, a ma laila ke kinoea H2 e hele ana ma ka filament e hoʻopuka koke i nā mana hydrogen. ʻO ka hana ʻana o ka hydrogen atomic i ka hydrocarbon pyrolysis i hoʻonui i ka helu deposition o nā kiʻi daimana. Hoʻopaʻa koho ʻia ke daimana a hoʻopaʻa ʻia ka hoʻokumu ʻana i ka graphite, ka hopena o ka hoʻopaʻa ʻia ʻana o nā kiʻi daimana ma ke kauoha o mm/h, ʻo ia ka helu deposition kiʻekiʻe loa no nā ʻano hana maʻamau i ka ʻoihana. Hiki ke hana ʻia ka HFCVD me ka hoʻohana ʻana i nā kumu kalapona like ʻole, e like me ka methane, propane, acetylene, a me nā hydrocarbons ʻē aʻe, a me kekahi mau hydrocarbons i loko o ka oxygen, e like me ka acetone, ethanol, a me methanol. ʻO ka hoʻohui ʻana o nā hui i loaʻa ka oxygen e hoʻonui i ka pae wela no ka waiho ʻana o ke daimana.

Ma waho aʻe o ka ʻōnaehana HFCVD maʻamau, aia kekahi mau hoʻololi i ka ʻōnaehana HFCVD. ʻO ka mea maʻamau ka hui pū ʻana o ka plasma DC a me ka ʻōnaehana HFCVD. Ma kēia ʻōnaehana, hiki ke hoʻopili ʻia kahi volta bias i ka substrate a me ka filament. ʻO ka hoʻopaʻapaʻa maikaʻi mau ma ka substrate a me kekahi ʻano maikaʻi ʻole ma ka filament ke kumu e hoʻokuʻu ai nā electrons i ka substrate, e ʻae ana i ka hydrogen o ka ʻili e desorb. ʻO ka hopena o ka desorption ka piʻi ʻana o ka helu deposition o ke kiʻi daimana (e pili ana i 10 mm/h), kahi ʻenehana i ʻike ʻia he HFCVD kōkua electron. ke kiʻekiʻe ka volta bias e hana ai i ka hoʻokuʻu plasma paʻa, piʻi nui ka decomposition o H2 a me nā hydrocarbons, e alakaʻi i ka piʻi ʻana o ka ulu ulu. Ke hoʻohuli ʻia ka polarity o ka bias (ua hoʻohālikelike ʻia ka substrate), hiki ke hoʻomake ʻia ka ion ma ka substrate, e alakaʻi ana i ka piʻi ʻana o ka nucleation daimana ma nā substrate non-diamond. ʻO kekahi hoʻololi ʻē aʻe ʻo ka hoʻololi ʻana o kahi filament wela hoʻokahi me nā filament like ʻole i mea e hoʻokō ai i ka deposition like ʻole a i ka hopena i kahi wahi nui o ke kiʻi daimana.

(2) Microwave Plasma CVD (MWCVD)

I ka makahiki 1970, ua ʻike nā kānaka ʻepekema e hiki ke hoʻonui ʻia ka manaʻo o ka hydrogen atomic me ka hoʻohana ʻana i ka plasma DC. ʻO ka hopena, ua lilo ka plasma i ʻano hana ʻē aʻe e hāpai i ke kūkulu ʻia ʻana o nā kiʻi daimana ma o ka hoʻoheheʻe ʻana i ka H2 i loko o ka hydrogen atomic a me ka hoʻoulu ʻana i nā hui atomika. Ma waho aʻe o ka DC plasma, ʻelua mau ʻano plasma i loaʻa i ka nānā. He 2.45 GHZ ka wikiwiki o ka microwave plasma CVD, a he 13.56 MHz ka RF plasma CVD. ʻokoʻa nā plasmas microwave i ka hoʻoulu ʻana o ka microwave frequency i nā haʻalulu electron. I ka wā e hui ai nā electrons me nā ʻātoma kinoea a i ʻole nā ​​molekole, hoʻopuka ʻia kahi kiʻekiʻe dissociation rate. Hoʻomaopopo pinepine ʻia ka plasma microwave ma ke ʻano he mea me nā electrons "wela", nā ion "anu" a me nā ʻāpana kū ʻole. I ka wā o ka waiho ʻia ʻana o nā kiʻiʻoniʻoni lahilahi, komo nā microwaves i ke keʻena synthesis CVD i hoʻonui ʻia i ka plasma ma o ka puka makani. He spherical maʻamau ka luminescent plasma, a piʻi ka nui o ka pōʻai me ka mana microwave. Hoʻoulu ʻia nā kiʻi ʻoniʻoni ʻoniʻoni daimana ma luna o kahi substrate ma kahi kihi o ka ʻāina luminescent, a ʻaʻole pono ka substrate e pili pono me ka ʻāina luminescent.

-Ua hoʻokuʻu ʻia kēia ʻatikala emea hana mīkini hoʻopaʻa haʻahaʻaGuangdong Zhenhua