Study on One2d im en sion W ell2a ligned ZnO W h iskers and D op ing by MOCVD

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1 34 6 Vol. 34 No JOURNAL OF SYNTHETIC CRYSTALS December, 2005 MOCVD ZnO,,, (, ) : MOCVD, Zn (C 5 H 7 O 2 ) 2, c,, ZnO, XRD ZnO, c ; ZnO, c SEM, ZnO, 20; ZnO, : ZnO; ; ;MOCVD : TN : A : X (2005) Study on One2d im en sion W ell2a ligned ZnO W h iskers and D op ing by MOCVD ZHAN G X ue2chuan, ZHAN G Yue, YUAN Hong2tao, WAN G Shu2bin (College ofmaterial Science and Engineering, Beihang University, Beijing , China) ( Received 14 July 2005) Abstract: Zinc oxide whisker arrays well2aligned along [ 0001 ] direction were grown on the substrates of glass and single crystal silicon by atmospheric m etal organic chem ical vapor deposition method (MOCVD). M ulti2gas p ipelines were used to transport different m etal organic compounds to p repare A l doped ZnO whiskers. XRD results indicate that undoped ZnO whiskers have a wurtzite2type crystalline structure, and grow strongly along the ZnO [ 0001 ] direction. A l2doped ZnO whiskers also have a crystalline structure of wurtzite2type, but grow slightly weak along the ZnO [ 0001 ]. The SEM observation show s that undoped ZnO whiskers have a regular arrangement and an aspect ratio of about 20. The morphology of doped ZnO whiskers became more and more anom alous w ith the increase of A l content. Key words: ZnO; one2dimension well2aligined m aterial; whisker; MOCVD 1 ZnO, 3. 36eV,, LED s LD s ZnO, cm ZnO, ZnO, ZnO n ZnO, ZnO, ZnO n p, : : (No ) : (19812),,, :, E2mail : zhangy@ buaa. edu. cn

2 6 :MOCVD ZnO 973, ZnO ZnO 1999 Saitoh [ 1 ] MOCVD 2A l 2 O 3 ZnO, ZnO,,,, ZnO, Won II Park [ 2 ] MOVPE ZnO, Peidong Yang [ 3 ] (CVTC) ZnO ZnO ZnO,,,, Saitoh, A l, ( mol % ),, 380nm, [ 4 ] D. P. Yu, Zn ZnCl 2 Mn ZnMnO [ 5 ] (AP2MOCVD ), A l ZnO, A l ZnO 2 [ Zn (C 5 H 7 O 2 ) 2 H 2 O, 99%, A lpha ], [A l(c 5 H 7 O 2 ) 3 H 2 O 99%, A lpha ], Si(111) ZnO A l ZnO 1 (99. 95% ),,,,,, 1 ZnO AP2MOCVD Fig. 1 Flow chart of AP2MOCVD system for growing ZnO whiskers 15m in ( KQ218, ) : Zn , 1. 0L /m in; A l 115, L /m in; 550 ; m in X ( D /max2200pc), CuK, 40kV, 40mA (JEOL, JSM5800) ZnO (L INK ISIS) ZnO A l ZnO EDS, 2

3 A l 0. 4L /m in 0. 6L /m in 0. 8L /m in 1. 0L /m in ZnO A l : 1. 88% 2. 59% 3. 56% 4. 24%, A l ZnO A l, A l, ( 3) 2 A l ZnO EDS 3 ZnO A l A l Fig. 2 EDS spectrum of the A l doped ZnO whiskers Fig. 3 Relation between A l concentration in the ZnO whiskers and the flow rate of A l organic vapor A l ZnO X 4 ( a) ZnO XRD ( 110, 550, 1. 0L /m in), ZnO ZnO (002), ZnO (004), XRD ZnO c ZnO (002) ( FWHM ) 0. 30, 4 ( b) A l (A l/zn ) 1. 88% 2. 59% 3. 56% 4. 24% XRD, ZnO c,, ZnO ZnO (001), (101) (102) (103), ZnO A l c, XRD ZnO,,, A l, ZnO ZnO A l 4 ZnO XRD Fig. 4 XRD patterns of the ZnO whiskers: ( a) undoped ZnO whiskers; ( b) A l doped ZnO whiskers with various A l contents

4 6 :MOCVD ZnO 975 ZnO, ZnO 4 ( b), ZnO ( 1. 88% 4. 24% ), (002), = 2dSin, 5, 1. 88% 2. 59% 3. 56% 4. 24% ZnO c nm nm nm nm, ZnO c nm, F. Paraguay D A l 5 ZnO c A l Fig. 5 Relation between cell parameter c of ZnO and A l content in A l doped ZnO c [ 6 ] A l nm Zn nm, A l Zn, A l2o Zn2O,, ZnO ; A l, A l ZnO, 3. 3 A l ZnO 6 6 a b 110, 550, 1. 0L /m in, 200m in ZnO SEM a,,, 0. 5 m, 10 m, 20,,,, ZnO ( b), /mm 2,, XRD,, [ 7 ] 6c2f A l ZnO SEM, 1. 88% 2. 59% 3. 56% 4. 24% A l, 6 ZnO SEM Fig. 6 SEM images of the ZnO whiskers. ( a) ( b) side2view and top2view of the updoped ZnO whiskers; top2view of the doped ZnO whiskers with various A l contents (c) 1. 88, ( d) 2. 59, ( e) and ( f) at%

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