Gushyira umwuka w’ubumara mu maraso (plasma) mu buryo bworoshye

Imiterere ya plasma
Imiterere ya plasma mu ishyirwa ry’umwuka w’ibinyabutabire bya plasma ni uko ishingira ku ngufu za kinetiki za electrons muri plasma kugira ngo ikore ibikorwa bya chemical mu cyiciro cya gaze. Kubera ko plasma ari uruhurirane rwa iyoni, electrons, atome zidafite aho zibogamiye na molecules, ntabwo ikoresha amashanyarazi menshi ku rwego rwa macroscopic. Muri plasma, ingufu nyinshi zibikwa mu ngufu z’imbere muri plasma. Plasma ibanza kugabanywamo plasma ishyushye na plasma ikonje. Muri sisitemu ya PECVD ni plasma ikonje ikorwa n’imyuka y’umuvuduko muke. Iyi plasma ikorwa n’imyuka y’umuvuduko muke iri munsi ya Pa magana make ni plasma y’umwuka idahuje.
Imiterere y'iyi plasma ni iyi ikurikira:
(1) Ingendo idahwitse y'ubushyuhe bwa electron na ions irenze icyerekezo cyazo.
(2) Uburyo bwo kuyishyiramo iyoni buterwa ahanini no kugongana kwa electron zihuta na molekile za gaze.
(3) Ingufu mpuzandengo y'ubushyuhe bwa electron iri hejuru y'ingano ya 1 kugeza kuri 2 ugereranyije n'iy'uduce duto duto, nka molekile, atome, iyoni na radicals yigenga.
(4) Ingufu zigabanuka nyuma yo kugongana kwa electron n'uduce duto dushobora kwishyurwa n'amashanyarazi hagati y'igongana.
Biragoye kugereranya plasma idahuje ubushyuhe buri hasi ifite ibipimo bike, kuko ari plasma idahuje ubushyuhe buri hasi muri sisitemu ya PECVD, aho ubushyuhe bwa electron Te butari bumwe n'ubushyuhe bwa Tj bw'uduce duto. Mu ikoranabuhanga rya PECVD, akazi k'ibanze ka plasma ni ugukora iyoni zikora mu buryo bwa shimi na radicals zigenga. Izi iyoni na radicals zigenga zigira ingaruka ku zindi iyoni, atome na molekile mu gice cya gaze cyangwa bigatera kwangirika kwa lattice na chemical reactions ku buso bwa substrate, kandi umusaruro w'ibikoresho bikora ni imikorere ya electron density, reactant concentration na yield coefficient. Mu yandi magambo, umusaruro w'ibikoresho bikora uterwa n'imbaraga z'amashanyarazi, umuvuduko wa gaze, n'ikigereranyo cy'ibyiciro bidafite aho bihuriye mu gihe cyo kugongana. Kubera ko gaze ihindura ibintu muri plasma yitandukanya bitewe no kugongana kwa electron zifite ingufu nyinshi, imbogamizi yo gukora ya chemical reaction irashobora kuneshwa kandi ubushyuhe bwa gaze ihindura ibintu bushobora kugabanuka. Itandukaniro rikomeye hagati ya PECVD na CVD isanzwe ni uko amahame ya thermodynamic y'imikorere ya chemical reaction aratandukanye. Kwitandukanya kwa molekile za gaze muri plasma ntabwo ari ugutoranya, bityo urwego rwa filime rubitswe na PECVD rutandukanye rwose n'urwego rwa CVD rusanzwe. Imiterere y'icyiciro ikorwa na PECVD ishobora kuba idahuje, kandi imiterere yayo ntikigengwa na kinetiki y'uburinganire. Urwego rwa filime rusanzwe ni urw'amofofo.

Ibiranga PECVD
(1) Ubushyuhe buke bwo gushyiramo ibintu.
(2) Gabanya umuvuduko w'imbere uterwa no kudahuza kw'umurongo w'ingufu z'inyuma z'urukiramende/ibikoresho by'ibanze.
(3) Igipimo cyo gushyiramo ibintu kiri hejuru cyane, cyane cyane ubushyuhe buke, ibyo bikaba byorohereza kubona filime zidafite isura n'izidafite ishusho.

Bitewe n'ubushyuhe buke bwa PECVD, kwangirika k'ubushyuhe gushobora kugabanuka, gukwirakwira hamwe n'ingaruka hagati y'urwego rwa filime n'ibikoresho bya substrate bishobora kugabanuka, n'ibindi, kugira ngo ibice by'ikoranabuhanga bishobore gupfukwa mbere yuko bikorwa cyangwa bitewe n'uko bikenewe kongera gukoreshwa. Mu gukora ibyuma binini cyane (VLSI, ULSI), ikoranabuhanga rya PECVD rikoreshwa neza mu gukora filime ya silicon nitride (SiN) nk'ifilime ya nyuma yo kurinda nyuma yo gukora insinga za electrode za Al, ndetse no gufunga no gukora filime ya silicon oxide nk'ubwirinzi bw'interlayer. Nk'ibikoresho bya filime nto, ikoranabuhanga rya PECVD ryakoreshejwe neza mu gukora transistors za thin-film (TFTs) zo kwerekana LCD, n'ibindi, hakoreshejwe ikirahure nk'ishingiro mu buryo bwa matrix. Hamwe n'iterambere rya circuits zivanze ku rugero runini no kwihuza cyane no gukoreshwa cyane kw'ibikoresho bya semiconductor, PECVD irasabwa gukorwa ku bushyuhe buke no ku ngufu za electron nyinshi. Kugira ngo iki gisabwa kigerweho, ikoranabuhanga rishobora gukora filime zirambuye ku bushyuhe buke rigomba gutezwa imbere. Filimi za SiN na SiOx zizewe cyane hakoreshejwe plasma ya ECR n'ikoranabuhanga rishya rya plasma chemical vapor deposition (PCVD) hamwe na plasma ya helical, kandi zageze ku rwego rufatika mu gukoresha filime zo gukingira hagati y'inyubako nini zivanze, nibindi.