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Phng phpngng t vt l (PVD)Phng phpngng t ha hc (CVD)CC PHNG PHP CH TO MNGPhysical Vapor DepositionChemical Vapor Deposition Vi mt tc nhn cung cp nng lng,vt liu cn ph mng b ha hi. Cc ht vtliu di chuyn Cc phnng hnhthnh hpcht (nu c),xy ra trnng i Cc ht vt liu ngng t trn Mng Vi mt tc nhn cung cp nng lng,vt liu cn ph mng b ha hi. Cc ht vtliu di chuyn Mt chtkh c avo (precursor) Cc ht vt liu ngng t trn ,phn ng vi cht kh Hp cht MngT < 5000CT 900 12000C

Phng phpbc bay chn khngPhng phpphn x HAI PHNG PHP PVD PH BIN

1. Phng php bc bay chn khng (Evaporation)Phng phpbc bay trc tipThermalEvaporation:Bc bay nhitPhng phpbc bay gin tipBc baynhit intrBc baybng chmin tBay hiphn ng(RE)M ionElectron-beamEvaporation:Bc bay bngchm in tIon Plating:M ionKhngkch hotC kchhot (ARE)Reacting Evaporation:Bay hi phn ngActivated Reactive Evaporation:B.hi p.ng c kch hot

1.1 Phng php bc bay trc tipBC BAY NHIT IN TR Nguyn tc chung Vt liu (rn, lng, bt)c cung cp E ha hi Hi vt liu bcln pha trn Cui cng, hi vt liu ngngt trn , phn b v kt tinhNhitChm eLaserH quangTc nhn ha hi l ngun nhit,mu c gi bng in trBC BAY BNG CHM eTc nhn ha hi l chm e cng nng ln

BC BAY NHIT IN TRMt h bc bay chn khng gm4 b phn chnh: H bm chn khng Bung chn khng Ngun nhit H gi & iu chnh TMu c gi bng gi in tr,c t nng n ha hi bngdng in theo L Joule-Lenz:S mt h bc baychn khng n ginCc loi gi in tr: dy(a-d), thuyn (e-g) v chn (h)Nhit lngta rain tr ca thuynCng dng inqua thuynThi gian ta nhit

GI IN TRThuyn in tr 1 hay nhiu vng dy Lm bng Vt liu cn bc bay c quntrong cc vng dyVng dy in trChn in tr Tm kim loi dng thuyn chavt liu Lm bng Chn c t nng bng cc siin tr qun quanh ni Lm bngThch anhchu nhitphAl2O3d > 1m

Tc bay hi(1):S nguyn t bc baytrong 1 n v thi gianDin tch b mt cangun bc bay.H s bc bay(2)p sut hi cn bngca cht bay hip sut cacht bay hi trongbung chn khngKhi lngnguyn tHng s Boltzmann(1,38.10-23J/K )Nhit tuyt i (K)Trong , p sut hi cn bng l 1 hm theo nhit :Hng sNhit n bc bay ca 1nguyn t hay phn t(1) Tc bay hi: S nguyn t bc bay i qua 1 n v din tch trong 1 nv thi gian.(2) H s bc bay (Evaporation Coefficient): H s dnh cht ca nguyn t bayhi trn b mt.Phng trnh Hertz-Knudsen

S phn b hng ca cc nguyn t bc bay:nh lut phn b Cosine:N0: s ht nm trnphng php tuynvi mu trong 1 nv thi gianNi: s ht nm trnphng hp viphng php tuyn1 gc i u im & hn ch ca p.p bc bay nhit in trU IMn ginR tinHN CHVt liu Tnng chy caoKhngHP CHT, HP KIM

BC BAY BNG CHM e Mu c cung cp nng lng ha hi t s va chm vichm in t c ng nng ln.Htvt liuChm eMuSng eCu to ca sng in tTh gia tc(6-10kV)Th tVt liucn phChm electronCun ttrngChn ng Cathode c t nng Phtx nhit in t, tun theo phngtrnh Richardson:Mt dngpht xnhit in tHng skim loiH s truynqua trung bnhNhit kim loiHng s BoltzmannCng thotca e rakhi kim loi

Chm electron cgia tc trong in trng,nh hng trong ttrng, va chm vi bmt vt liu.Th gia tc(6-10kV)Th tVt liucn phChm electronCun ttrngChn ng u im & hn ch ca p.p bc bay bng chm eU IMHN CH Chn ng mu cgii nhit bng nc trnh hao mn.Vt liu Tnng chy caoHP CHT, HP KIMThit b t tin!

BC BAY BNG XUNG LASER(PLD Pulse Laser Deposition)++++++ElectronNguyn ttrung ha+Ion +Laser Chm laser xung cngsut ln c chiu vo bia. Bia hp thu nng lnglaser, nng ln v bay hi Pha trn bia hnh thnhmt vng khng gian chaplasma pht sng Cc ht vt liu biangng t mng trn Thng tin v ngun laser xung thng s dng Laser Excimer KrF: = 248nm di xung: t = 25ns Mt cng sut: j = 2,4.108W/cm2

Vng din tch chiu ri ln bia: A = 0,1cm2 Tn s lp li: f = 50Hz

Nng lngLASERbia hp thuCung cp ng nngln cho ht vt liuKch thch e thotra khi biaKch thch, ion hanguyn t vt liuHNH THNH PLASMATrong qu trnh n biaPh v lin ktmng thot khi biaNguyn t, cmnguyn t trung haKch thch ionnguyn t vt liuNguyn tkch thchIonkch thchTrng thic bnPhtsngu im ni bt nht ca p.p PLD: ph mng trn nhng tinh viMc chn khngGin dch chuyn nnglng ca e,nguyn t, ion +++++

1.2 Phng php bc bay gin tipKP:Phng php bcbay trc tipHIN TNGPHN LYHp chtMng khng tinhkhit / b bin chtPhng php bc bay gin tipBay hiphn ng(RE) Bia l vt liu n cht Mt kh n cht ca vo bung chn khngAB Phn ng A & B Vt liuhp cht (AxBy)(khng kch hot)Thng dng mng oxitkim loi nhTiO2, SiO2,...

Bay hi phn ng (RE)PHN NG A &B KH XY RATc lng ngmng NHHp chtHp cht Carbides: TiC, VC,NbC, Cr3C2...; Hp cht Nitrides:TiN, VN, ZrN,...; Oxides: Al2O3KP:P.P. bay hi phn ng c kch hot (ARE) C thm 1 dy l xo, c t nngbi ngun in V1 Pht x nhit in t in t pht x c gia tc bi intrng V2 Va chm kch thch kh A, B Phn ng gia A v B xy ra vi xc sut ln Hp cht AxByV1V2

V1V2M ion(Ion Plating) Xut pht t m hnh bay hi phn ngABAxBy Mt dy tc c t nng Pht x nhit in t in t pht x gia tc trongin trng Va chm ion haphn t AxBy thnh ion (AxBy)-AxBy(AxBy)-e- (AxBy)- gia tc trong in pgia bia-, hng v vinng lng ln Hp cht AxByU IM bm dnh mng- tt Mt mng cao

2. Phng php phn x(Sputtering)Phn xdiode phngPhn xMagnetronP.X.Mdng mtchiu (DC)P.X.Mdng xoaychiu (RF)P.X.Mkhngcn bngP.X.Mcn bngVbia-H magnetronP.X.M DC cn bngTrc tipPhn ngP.X.M DC khng cn bngP.X.M RF cn bngP.X.M RF khng cn bng

2.1 Phn x diode phng Trong vng khng gian bn trongbung chn khng, c sn mt sion dng v e-++++++++ p mt in th DC ln bia-,ion + tin v bia, e- tin v +++ Ion + nh btht vt liu trn bia: ht phn x Ht vt liungng t trn , lp mng. Ion + va chm b mt bia pht x e th cp va chm ion ha snsinh ion + duy tr plasma v phng in. Mt kh n cht (thng l Ar) c a vo lm gia tng ion +trong va chm ion ha.

u im & hn ch ca p.p phn x diode phngU IMHN CH Khng tnng trctip vt liuCht bay hiThuynTp cht

thuyn2.2 Phn x magnetron Phi dng Vbia- ln lmth mi phng in S mt mt e th cp ln Tc lng ng nhKP: T m hnh p.x. diode phng, c thm h magnetron,h cc nam chm nh hng N-S nht nh ghp vi nhau

Cc tm mCc ng sc t trngTm st ni t H magnetron c gn bn di bia, di cngl tm st ni t. e th cp sinh ra t va chm gia ion + v bia,chuyn ng c bit trong in t trng.

c trng ca qu trnh phn xKhong khng gian gia anodev cathode c th chia lm 3vng (Mi vng c phn b thnng khc nhau):Vng st th Cathode: e th cp va mi c sn sinh t va chm ion + v bia, in th m tng dn (st th), ve nh v c gia tc trong in trng.Vng ion ha: e chuyn ng c bit trong in t trng vi ve ln, ion ha nguyn t kh, lm tng mt e, in th m tng n gi tr ngng, ri gim do qu trnh ti hp.ve: vn tc e th cpVng plasma: mt ion + gim dn, do , in th m tng chm dn.CathodeAnodeV = |-Ve|123123

Qu o chuyn ng ca e e chuyn ng trong t trng schu tc dng ca lc Lorentz. Hnglc tun theo Quy tc Bn tay tri:T trngVn tc htLc Lorentz+-- Trong h phn x magnetron, e chuyn ng va trongt trng (khng u), va trong in trng (u).SNNSSNXem nh t trng uintrng-yzx-yx(hng v)

-yx(hng v)O Gi s, e th cp va thot ra khi biac v 0. Ti O, e ch chu tc dng cain trng E, di chuyn n O. Ti O, e c v1 0, nn chu tc dngca lc Lorentz theo phng x. V v1 cnnh nn fLoz < Fin. e di chuyn n M.OFinfLozM e gia tc trong in trng. Ti M, e cv2 > v1, fLoz ln hn O v tin ti bngFin. e di chuyn n N. Ti N, e c v3 > v2, fLoz ln hn Fin , e dichuyn n P ri n Q.fLozfLozNvP-yx(hng v)-e chuyn ng theo qu o cycloid (hay qu o trng ua)-SNH magnetron lm tng qung ng ichuyn ca e tng kh nng ion ha.in trng Ti Q, fLoz bt u gim nhng vn cnln hn Fin, e c v4 < v3. C th, sau 1lc, fLoz = Fin, e tr v nm trn trc Oxv mt chu k mi bt u.Q-

Phng trnh chuyn ng ca in t trong in trngv t trng vung gc c dng:Trong :Ey: ln ca vector cng intrng theo phng yH: ln vector cng t trngt: thi im kho st H magnetron cn bng v khng cn bngH magnetron cn bngH magnetron khng cn bngH mag-netroncn bng,cc namchm ccng nh nhau.Cc ngsc ttrngkhp kn.H mag-netronkhngcn bng,nam chm gia ccng yu hn.Cc ngsc ttrngkhngkhp kn.

H magnetron cn bngH magnetron khng cn bngT trngkhp knCc e chu tc dngca t trng ngange ch yu chuynng gn bia t b eva p t bt nngThch hp to mng chocc loi khng chuc T0 cao: nha, giy,(hng v)T trngkhng khp knCc e t chu tc dngca t trng ngange theo in trngn vi v ln b nhiu eva p mnh bt nngThch hp to ccmng yu cu T0 caoin trng

H phn x DC v RFH phn x mt chiu(DC Direct Current)H phn x xoay chiu(RF Radio Frequency)Vanode-cathode lmt chiuBia s dngphi dn inphnginVanode-cathode lxoay chiuduy trB tr khngv h t inTng cng sutphng inBia s dngcch inVbiaIon + bn phe- bn pht

u im & hn ch ca p.p phn x magnetronU IMHN CH

PHNG PHP SOL-GEL H cc ht phn tn,kch thc: 0,1 1m Lc tng tc giacc ht: Van der Waals Cc ht chuyn ngBrown, va chm nhauHt solDung dch ng tli thnh keo Sau mt thi gian,cc ht sol ht nhauH SOLH GELCht ban u to nn H SOLPRECURSORCng thc chung: M(OR)xM: nguyn t kim loiR: nhm alkyl (CnH2n+1)Mt s precursor ph bin: Tetramethoxysilan (TMOS) Tetraethoxysilan (TEOS) Alkoxy Aluminate Alkoxy Titanate Alkoxy Borate ...

Cc qu trnh xy ra khi t h sol h gelH SOLH GEL123Phn ng thy phn M(OR)n + xH-OH M(OR)n x(OH)x + xROH Nhm alkoxide (-OR) Kim loi Nhm hydroxyl (-OH) Kim loi Phn ng ngng t M(OH)(OR)n-1 + M(OR)n (OR)n-1M-O-M(OR)n-1 + ROH Ngng t ru Ngng t ncM(OH)(OR)n-1 + M(OH)(OR)n-1 (OR)n-1M-O-M(OR)n-1 + H2O Sau phn ng ngng t, dung dch c c li thnh khi rn Thiu kt T0cao: mu chuynpha v nh hnhsang tinh th

Hai phng php to mng t qu trnh sol-gelPh nhng(Dip Coating) Ph quay(Spin Coating) c nhng vodung dch sol, sau c ko rat t mng/ dmng ph thuc: vko,gc ko, nht, nng dd,... Khng uDung dch c nhln v cho quay.Lc ly tm mu gitlan ta u trn mng/dmng ph thuc: nht, vbay hi, vquay,... ng u u im & hn ch ca phng php sol-gelU IMHN CHn gind dngkim sotCpha tpKHkim sot dy mng

Cm n Thy v cc bn quan tm theo di

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