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I HC QUC GIA TP.HCMTRNG H KHOA HC T NHIN

KHOA VT LBM VT L NG DNG

MN : CC PHNG PHP THC NGHIMCHUYN NGNH

BO CO TIU LUN :

NGHIN CU TNH CHT QUANGIN CA MNG MNG TiN

GVHD : L Trn

HVTH : Phm Vn Thnh

TP.H Ch Minh, ngy 12 thng 04 nm 2010

HV :Phm Vn Thnh Lp Cao hc VTDT Kha 19

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I. GII THIU MNG TiN

Ngy nay, mng mng c nhiu ng dng trong nhiu lnh vc nh:c, nhit, in , tc bit trong lnh vc quang hc, mng mng cng dng rt a dng nh: mng kh phn x n lp v a lp, mng dnin trong sut, mng quang tch hp, gng lnh, gng nng ...

Mt s tnh cht ca mng TiN :Mng TiN l vt liu c mu ca kim lai vng, cng cao (21 - 24

GPa), chu nhit (nhit nng chy l 29500C), chng n mn, v c in trsut kh nh (20 - 30.cm). Hn na, mng mng TiN c phn x caotrong vng hng ngoi, chit sut thp v h s tt cao nh mng Au, rtthch hp lm lp gia trong h thng mng a lp. Tuy nhin, ty vo mcch s dng khc nhau m nhiu tc gi s dng cc phng php chto mng khc nhau trn cc lai khc nhau. Vi mc ch dng mngTiN lm hng ro khuych tn trong cng ngh IC, mt s tc gi chto mng TiN trn Si, cho in tr sut c 25.cm . Mt s tc gikhc ng dng tch cht c hc ca mng v ng dng cho mc ch trangtr, h s dng thp (304) hoc MgO(001), kt qu cho mng TiNc in tr sut c 13.cm - 192.cm, mt s cng trnh khc, tc gich to mng TiN trn thy tinh th li cho kt qu in tr sut t 50-200.cm.

Hnh1 : Gin nng lng cc hp cht ca Ti

II. CC PHNG PHP XC NH TNH CHT CA MNGCc tnh cht ca mng c nghin cu bng cch s dng phng

php o nhiu x tia X, phng php bn mi d, ph truyn qua quanghc.1. Xc nh thng s quang hc1.1. Phng php ph truyn qua

xc nh c cc thng s quang hc ca mng mng ( dy, chitsut, h s hp th, h s tt) ta tin hnh xc nh ph truyn qua camng. T cc thng s ca ph truyn qua thu c v bng phngphp tnh ton ta s xc nh c cc thng s quang hc ca mng.


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1.2. Phng php Ellipsometry

2. Phng php xc nh cu trc mng2.1. Phng php nhiu x tia X2.2. Phng php Stylus2.3. Php o hiu ng Hall2.4. Phng php s dng phn mm khp ph Scout- Mc ch: dy, chit sut, rng vng cm, in tr sut, nng htti v linh ng.- Nguyn tc:

Khai bo cc d liu: vt liu to mng, cc thng s quang ban uca vt liu

Xc nh loi ph cn lm khp, v ph l thuyt ca n da trn ccthng s khai bo

Chn cc thng s mun lm khp sao cho ph l thuyt trng khpvi ph thc nghim nht.

Thay i dn cc thng s kt qu lm khp l tt nht. T taxc nh c cc thng s ca mng.

3. Xc nh in tr sut3.1. Phng php o in tr vung3.2. Phng php o bn mi d

Vi :

G : S hiu chnh (ty thuc vo hnh dng v kch thc ca mu)

Hnh 3 : Mch bn mi d

III. NG DNG T MT S TNH CHT CA MNG TiN1. Mng phn x trong h mng a lp1.1. Gii thiu

Trong nhng nm gn y nhiu tc gi trong v ngoi nc vang tp trung nghin cu v mng gng nng truyn qua mng c

.sR d . .ln 2sU

R GI


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truyn qua cao vng kh kin (bc sng: 380nm 760nm) v phnx cao vng hng ngoi ( 760nm). Mng gng nng truyn qua cth c to ra bng nhiu hng nh:

- Mng dn in nh: Bc, vng v ng c phn x cao vnghng ngai, hp th t vng kh kin (mng kim loi thng khngbn v nhit, c v ha hc)

- Mng bn dn c phn x cao vng hng ngai nh: MgO, ZnO,NiO, SiO, SnO2 , Bi2O3, PbO v In2O3; Bn dn pha tp SnO2:F,SnO2:Sb, ZnO:Al, ZnO:Ga, ITO (Mng bn dn phn x cao vngbc sng > 2000nm, rt xa so vi cc i ph bc x nng lngmt tri)

- Mng a lp in mi-kim loi hoc in mi-kim loi-in mi.Mng a lp c kh nng khc phc c nhc im ca mng bndn pha tp l c vng bc sng phn x rng > 760 nm nhng bnhn mng kim loi v c, nhit v ha hc.

Trong , mt s loi mng a lp in mi-kim loi-in mi, cnhiu tc gi nghin cu nh : SiO2/Al/SiO2, Al2O3/Mo/Al2O3,TiO2/Ag/TiO2, Al2O3/Cu/Al2O3, ni tri nht l h mng a lpTiO2/Ag/TiO2, v TiO2 c chit sut cao nn kh phn x tt v n l mngc bn c hc cao. Tuy nhin, lp kim lai Ag gia khng bn v chc, ha hc ln nhit hc theo thi gian. Do , ta cn nghin cu vt liuthay th mng Ag nh mng TiN - mng ny c bn c hc, ha hc lnnhit hc rt cao v c tnh cht quang in ging mng kim loi Au.

Trong cng trnh ny, ta lng ng mng TiN trn thy tinh kimvi mc ch nghin tu tch cht quang v in ca mng ng dng lmmng phn x trong h mng a lp. V vy, trong cng trnh ny ta nghincu, tm nhng iu kin ti u ch to mng TiN c chit sut thp, hs tt k ln, ngha l mng c in tr sut thp hay phn x cao vnghng ngai. Do , mng TiN phi c cu trc c, tc l mt khi ln.in tr sut ca mng TiN ph thuc vo nng ht ti v linh ngca in t dn. Mng TiN c lin kt ho hc tng t kim loi, nn nng ht ti cao (c 1022 ht/cm3). Vy yu t lm gim in tr sut camng TiN ch yu l do linh ng ca in t dn quyt nh. V th, to c mng c in tr sut thp, cn trnh to mng c cu trc xpvng I (m hnh Thornton). Ngh a l trnh to mng c nhiu bin httrng. Mun vy, ta cn phi to mng theo c ch nhit ng hc v nghc.

Theo c ch nhit ng hc, ta cn cp nhit ln lm tng linh ng ca cc nguyn t ti v lm chng d dng khuych tnvo nhng v tr bn trong mng tinh th, lm cho Titan v Nit d hp thchn. Vi nhit ln sao cho Ts>0,3Tm (ln hn 5000C), mng s c cutrc ct c trong m hnh Thornton. Tuy nhin, nhit trong tiny ch thay i t 1500C n 4000C, khng p ng c m hnhThornton. Hn na, nhit qu cao d gy ra cho thnh bung chn khnggii hp nhng tp cht v gy tp trong mng. Vy gim in tr sutca mng, ta cn p dng c ch th hai l c ch ng hc. Ngha l tng


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cng mt ion nng lng cao n mng nh cc ion Ar+, N 2+, N+. Vvy, chng ti s dng h magnetron gn cn bng. Mc ch l tngcng s truyn xung lng gia ion nng lng cao cho nguyn t hp thnh Ti v N2 trn b mt mng, lm tng linh ng ca nhng nguyn thp th v dn n tng s khuch tn ca chng vo mng tinh th nhng v tr bn. ng thi tng kh nng hp thc gia Titan v Nit lmcho mng c cu trc c.

1.2. Thc nghim v kt quMng TiN c ch to bng phng php phn x phn ng

Magnetron dc trn thy tinh, h chn khng lm vic c p sut ti hn10-4 torr vi bia lm bng vt liu Titanium, tinh khit 99.6%, kchthc bia 100x100x6(mm). Kh lm vic l kh Argon (99.99%) v kh ho ttnh l kh Nit (99.99%), chng c trn ln theo t l cho trc v ca vo bung chn khng bng h van kim. H magnatron c dng ckch thc 119x119x51(mm), t trng trn b mt bia c to bng loinam chm vnh cu Ferit, cng t trng khong 350 Gauss. Qu trnhto mng c tin hnh vi p sut 3.10-3 torr n 6.10-3 torr, khong cchgia bia v thay i c, th phn x thay i t 350 V n 650 V, t lkh N2 so vi Ar thay i t 5% t 15%. B dy mng c xc nh bngphng php Stylus, in tr mt ca mng c xc nh bng phngphp bn mi d. Cu trc tinh th v kch thc ht ca mng c xcnh da vo ph nhiu x tia X. Chit sut n v h s tt k ca mng cxc nh bng phng php Ellipsometry

1.2.1.Tnh cht inKho st nh hng ca th phn x theo t l kh Nit v Argon.

Vi mi t l % ca Nit v Argon, chng ti kh o st in tr sutca mng theo th phn x nh th (Hnh 11) v tm c in tr sutthp ng vi th phn x ngng. Kt qu nhn c cho thy in tr sutgim theo th phn x, l do s truyn xung lng gia ion v nguyn tTitan tng, lm tng linh ng ca nguyn t hp th Titan trn b mt,dn n phn ng gia Titan v Nit tng cho mng h p thc tt. iu nyc th hin r ph nhiu x tia X.

T ph nhiu x tia X (Hnh 12) cho thy nh ph tng ng mt(111) gim khi tng th phn x l do c s gii phng nng lng, lmgim nng lng b mt, tc l lm tng nng lng bin dng, bc tinh thtng. Khi th phn x t gi tr ngng th mt (200) v (311) xut hinng thi mng c in tr sut thp nht. S xut hin ca nh ph (200)v (311) gii thch cho mu Q54 c in tr sut nh 3,5.10-5 ( cm). intr sut ca cc mu tng hay gim th hin qua s thay i t l cng ca mt (200) v (311) T kt qu kho st trn, ta thy ng vi mi p sutring phn ca Nit, ta tm c th phn x ngng c th thng cs Nitride ha trn bia v to hp thc tt trn mng v nh th c th choin tr sut thp. V vy ta cn thay i t l kh gia Nit v Argon. ngthi thay i th phn x ti tng p sut ring phn ca Nit. Kt qu cho


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thy vi t l % ca Nit v Ar l 10 th th phn x ngng l 550 V, khi mng c in tr sut thp nht (mu Q54)

Ngoi c ch truyn xung lng gia ion v nguyn t Titan, khi tngth phn x t n gi tr ngng, c ch trung ha Auger xy ra c nghal in t dn in th nht t Ti chuyn qua trng thi c bn ca ion N2bng hiu ng ng hm, trung ha n v ng thi trao nng lng thacho in t th hai trong vng dn in, kch thch n ln min nng lnglin tc. Vy, khi tng th phn x, Nguyn t trung ha N2 gii phng tb mt bia Ti v c cp nng lng c th p vo bia. Do vy, N2 n ,lm tng nng lng truyn cho , v n lin kt vo trong mng nhiuhn, dn n in tr sut ca mng thp.

Hnh 11. Biu din s nh hng ca in tr sut theo th phn x, ngvi tng t l phn trm ca Nit v Argon

Hnh 12.Ph nhiu x ca cc mng TiN c to theo th phn x khcnhau v cc thng s: t l N2/Ar l 10%; p sut lm vic p=3mtorr


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Kho st s nh hng ca in tr sut theo khong cch bia Khong cch gia bia v cng l vn quan trng cn phi kho

st. Nu khong cch qu xa th nng lng ti truyn cho mng khng ln v v th mng c cu trc tinh th cha tt , nu khong cch gn thdng ion bn ph s lm tng sai hng. mt khong cch ti u, s truynxung lng gia ion v mng s cho hp thc tt v nng lng bn phca ion cha vt qua ngng gy ra sai hng trong mng. Cng trnhny tm c khong cch ti u l 4,5cm (mu Q54) th mng c in trsut thp nht

Hnh 13: Biu din s nh hng ca in tr theo khong cch bia


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Hnh 14. Ph nhiu x ca cc mng TiN c to vi cc thng s:Up=550 V; t l N2/Ar l 10%; p sut lm vic p=3mtorr, nhit l2000C. khong cch bia v thay c : h=3,5cm; h=4,5cm; h=5,5cm

Kho st s nh hng ca in tr sut theo nhit Ngoi cc thng s nh cng dng phn x ngng, khong cch

gia bia v , nhit cng l thng s quan trng, nh hng n qutrnh hnh thnh tinh th ca mng. (Hnh 15) cho thy 3000C, bc tinh th

ca mng ln nht, th hin thng s 311T

I

Iln, lm tng linh ng ca

in t, khi mng c in tr sut thp c 3,5.10-5 cm (mu T71) nh(Hnh 16). Tuy nhin, khi nhit tng n 4000C, vt liu trong bungchn khng nh kh, lm cho mng c nhiu tp, dn n bc tinh th gim

th hin qua 311T

I

Igim. V th linh ng ca in t gim ng ngha

vi in tr sut tng.

Hnh 15:Biu din s nh hng ca in tr sut theo nhit


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Hnh 16.Ph nhiu x ca cc mng TiN c to vi cc thng s: Up =550 V; t l N2/Ar l 10%; p sut lm vic p = 3mtorr; khong cch bia

l h=4,5 cm ; nhit thay i t 2000C n 4000C

Kho st s nh hng in tr sut theo p sut phn x

Hnh 17. Biu din s nh hng ca in tr theo p sut

p sut cng l mt thng s quan trng lm nh hng n tnh chtca mng. Thc vy, p sut cao, cc ion N2+, N+ v cc nguyn t Ti b


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tn x bi cc phn t kh, v v th xung lng ca chng truyn cho gim. iu ny lm cho linh ng ca nguyn t hp th trn b mtgim. Nu gim p sut th s truyn xung lng gia ion N2+, N+ vnguyn t Ti tng, lm tng linh ng ca nguyn t hp th Ti trn bmt, dn n phn ng Titan v Nit tng, gii phng nng lng, lm gimnng lng b mt, tc l lm tng nng lng bin dng, nn cng mt (111) gim. in tr sut ca mng gim. iu ny do c ch tn x caht ti bi mt phn cc (111). Tuy nhin nu tip tc gim p sut lm victh lng Nit s qu t c th to c mng TiN. Nu p sut thp hn3mtorr th thnh phn Titan trong mng s tng, mng s c mu trng cakim loi Titan.

1.2.Tnh cht quangChit sut n v h s tt k ca mng mng TiN

Hnh 18. Ph nhiu x ca cc mng TiN c to theo p sut phn x vcc thng s: Up= 550 V; t l N2/Ar l 10%,khang cch bia h =4,5cm;

nhit 2000C


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Hnh 19. Chit sut n v h s tt k ca mu L1 theo bc sng

Hnh 20. Chit sut n v h s tt k ca mu L4 theo bc sng

Hnh 21.Ph phn x ca mu L1 theo bc sng.


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Hnh 22. Ph phn x ca mu L4 theo bc sng

Trong phn 1.2.1 ta tm c mng c in tr sut thp c35.cm nhit 200oC v 300oC. T cng thc thc nghim:

20 0(1 2 )sR c R

vi Rs l in tr mt ca mng ,0 0

1376

c . ta nhn thy gia tnh cht

in v tnh cht quang ca mng c mi lin h sau: khi mng c R s nhth h s phn x R ln, do ta ch kho st tnh cht quang ca mng cin tr sut thp nh cp. nhit 300oC, mng L4 vi b dy33nm c chit sut v h s tt bc sng 550nm l 1,35 v 3,49 (Hnh20). Hai lai mng ny c cng b dy v in tr sut. Mc d chng ccng in tr sut, phn x trong vng hng ngai ca mng L1 (Hnh21) l cao hn so vi mng L4 (Hnh 22). V vy chng ti chn nhit ti u to mng l 200oC.

1.3. Kt lunMng TiN to c c cu trc tinh th cao, tn ti cc mt mng

(111), (200) v (311). Mng c i n tr sut thp =35.cm ng vi ccthng s to mng ti u: Th phn x ngng Up=550V, t l N2/Ar =10%, khong cch gia bia h = 4,5cm, p sut phn x tan phn P =3.10-3 torr, nhit 2000C. Chit sut v h s tt ca mng bc sng550nm l 1,14 v 2,13.

TI LIU THAM KHO


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[1]. L Trn, Trn Vn Phng, Trn Tun, Nguyn Hu Ch, Nghin cuch to mng tin bng phng php phn x phn ng magnetron DC,(2008)

[2]. L Trn, Nguyn Duy Nhun, Ng Hng Cng, Nguyn Hu Ch,Trn Tun, Mng gng nng truyn qua quang xc tc TiO2/TiN/TiO2(2009)

[3]. Ion Dima, Benedict Popescu, Floriana Iova, Gabriela Popescu,Influence Of The Silver Layer On The Optical Properties Of TheTiO2/Ag/TiO2 Multilayer, Thin Solid Films, (1991).

[4]. J.-E. Sundgren, Structure And Properties Of Tin Coatings, Thin SolidFilms, (1985).[5]. H.K. Pulker, Coating on Glass, Elsevier, (1984).[6]. M. A. Angadi, k. Nallaamshetty, Heat mirrors using CeO2/Cu/CeO2multilayer films, Journal Of Materials Science Letters S, (1989).[7]. J. E. Sundgren, Structure And Properties Of Tin Coatings, Thin solidFilms, (1985).[8]. Patrick R. LeClair, Titanium Nitride Thin Films by the Electron ShowerProcess, Massachusetts Intitute Of EchnologY, May (1998).[9]. Donald .L Smith, Thin Film deposition- principle and practice , McGraw-Hill, Inc, New York San Francisco Washington DC, (1995).[10]. M. Kawamura, y. Abe, H. Ya nagisawa, K. Sasaki, Characterization ofTiN films prepared by a conventional magnetron sputtering system:influence of nitrogen flow percentage and electrical properties, Thin SolidFilms (1996).[11]. C. S. Shin,S. Rudenja, D. Gall, N. Hellgren, T. -Y. Lee, I. Petrov,aandJ. E. Greene, Growth, surface morphology, and electrical resistivity of fullystrained substoichiometric epitaxial TiNx 0,67 x


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[17]. G.Frank, E.Kauer And H.Ko stlin, Transparent Heat- ReflectingCoatings Based On Highly Doped Semiconductors , Thin Solid Films,(1981).[18]. Wen-Jun Chou, Ge-Ping Yu, Jia-Hong Huang, Mechanical propertiesof TiN thin film coatings on 304 stainless steel substrates , Surface andCoatings Technology (2002)

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