Growth of A lgan f ilm s w ith d ifferen t A l fraction on A ln tem pla te

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1 15 6 Vol115, No JOURNAL OF FUNCTIONAL MATER IALS AND DEV ICES Dec., 2009 : (2009) AlN Al AlGaN,, (, ;,, ) : 200nm A ln, XRD 130arcsec, nm A ln A l A lgan, XRD, A l, A ln A lgan,, A lgan A l 0. 67,, A lgan : MOCVD, A lgan, : TN304, O484 : A Growth of A lgan f ilm s w ith d ifferen t A l fraction on A ln tem pla te ZHOU Xiao2wei, L I Pei2xian, HAO Yue, CHEN Hai2feng, DU Yang ( School of M icroelectronics, Key Laboratory for W ide B and - gap Sem iconductor M aterials and Devices of M inistry of Education, Xidian University, Xi an , China) Abstract: 200nm A ln film is grown by pulse MOCVD. It s Fullwidth at halfmaximum ( FWHM ) of XRD rocking curve is only 130arcsec and root mean square (RMS) roughness is nm. U sed A ln as tem2 p late, A lgan film s with different A l fraction are grown. H igh resolution XRD measurement indicate that comp ressive strain which A ln temp late app ly to A lgan film s and tensile strain which come from coales2 cence of islands in A lgan film s increase with increasing A l fraction. W hen the A l fraction is about 0. 67, the tensile strain and the comp ressive strain is in the balance, the A lgan film has best quality. Key words: Pulse MOCVD; A lgan M aterial; Film Strain 0 GaN,,, [ 1-2 ], A l A lgan, : ; : : ( ) 863 (2996AA03A108). : ( ),, ( E - mail: zhouxiaowei0924@163. com).

2 576 15, Kam iyama [ 3 ] A ln GaN A lgan Han [ 4 ] A lgan A lgan, Bykhovsky [ 5 ] Zhang J. P [ 6-7 ] GaN /A ln GaN /A lgan, Khan A ln, A ln LED, [ 8-11 ] A ln A lgan, 0 1 A lgan, A ln A l,, A ln, A ln, A l A lgan, AFM SEM XRD 1 MOCVD, (0001), NH 3 TMA TEG N A l Ga, H 2 Fig. 1 The relation between input and interrup t in p luse MOCVD nm A ln, 1050 A ln, 1, TMA, NH 3, 6 s A ln, TEG TMA, A l A lgan Philip s X pert X, A ln 2 A ln, 300nm XRD,, A ln 546arcsec, 130arcsec;, AFM, 3, MOCVD ( 3 ( a) ), nm, nm, XRD AFM,, A l N A ln, NH 3 N,, ; A l N N A l A l - N, A l,, Fig. 2 XRD scan rocking curve of A ln film s grown by ( a) normal and ( b) p luse MOCVD 2 ( a) ( b)mocvd A ln XRD

3 6, : A ln A l A lgan 577 Fig. 3 The morphology of A ln film grown by ( a) normal and ( b) p luse MOCVD 3 ( a) ( b)mocvd A ln, A ln, A l A lgan 2. 2 A lgan A lgan 4, XD nm A ln, TMA TEG, 400nm A l A lgan XRD GaN A ln, A lgan, A l, XRD A l, A ln A l A lgan 5 XRD - 2, A ln ( XD1023) A B C D, A lgan, A ln,, A l, A lgan,, A ln A B C D XD1023 A ln, A < B < C < D. B ragg, A ln c c A > c B > c C > c D,, a a A < a B < a C < a D, A l, A ln Fig4 The structure of the samp le 4 A lxga1 - XN A l,, E g, A lgan ( x) = (1 - x) E g, GaN + xe g, A ln - bx (1 - x) E g, GaN = 3. 4ev, E g, A ln = 6. 2ev, b = 0. 9 [ 12 ] 1 A l 1 A lgan A l Table 1 The A l fraction of the A lgan samp les A B C D ( nm) A l Fig. 5 The XRD - 2 scan curves of samp les 5 XRD - 2 GaN a nm,

4 A ln nm [ 13 ], a A ln < a A lgan < a GaN A l2 GaN, A l, a A ln A lgan,, A l, A lgan A ln, A lgan A ln a F1, XRD, A ln A lgan F2, F2 > F1 F2, A l A lgan, A l,,, 3 ( b) A ln, A l A lgan, F2, A l,,, A ln A l2 GaN, A lgan A ln,, F A < F B < F C < F D Fig. 6 The XRD rocking curves of A lgan (0002) p lane 6 A lgan (0002) XRD ( FWHM ) A l A lgan XRD ( 6 ), A B C D 347arcsec 316arcsec 207arcsec 330arcsec, C Fig. 7 The relation between Al fraction and FWHM of rocking curve 7 A l FWHM A l 7 A l, A lgan, A l 0. 67,, ;, SEM A l, 8 A,, A lgan ; B, ; C, ; D, A l2 GaN SEM, A lgan A l 0. 67,, 200nm A ln A l A lgan,

5 6, : A ln A l A lgan 579 A ln,,, A lgan A l, A lgan, A ln, ; A l, A lgan, A ln, A lgan, A l 0. 67, A lgan ; A l, A lgan, 200nm A ln, Fig. 8 The SEM morphology of different A l fraction samp les 8 A l SEM 3 A l, A ln 200nm A ln A l A lgan, A ln A lgan A lgan A l, A ln A l, A ln A lgan, ; A l,, A l 0. 67,, ; A l, A lgan, A ln A lgan,, 200nm A ln A lgan A l, : [ 1 ]J ianp ing Zhang, Xuhuong Hu, et al. A lgan Deep - U ltravi2 olet L ight - Em itting D iodes Jpn, J. App l. Phys. Vol. 44, No. 10: [ 2 ] Ting Gang Zhu, U ttiya Chowdhury, et al. A lgan /A lgan UV light - em itting diodes grown on sapphire by metalorgan2 ic chem ical vapor deposition. Journal of Crystal Growth. 2003, 248: [ 3 ] S. Kam iyama, M, Sawaki, et. al. Low - temperature - depos2 ited A lgan interlayer for imp rovement of A lgan / GaN het2 erostructure. Journal of Crystal Growth. 2001, 223: [ 4 ]J. Han, K. E. W aldrip, S. R. Lee, J. J. Figiel, S. J. Hearne, G. A. Petersen and S. M. Myers. Control and elim ination of cracking of A lgan using low - temperature A lgan interlayers. 2001, App l. Phys. Lett. 78 : [ 5 ]A. D. Bykhovski, B. L. Gelmont and M. S. Shur. Elastic

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