Sains Malaysiana 40(3)(2011): 209–213
Effects of
Annealing Conditions on the Surface Morphology and Crystallinity of Sputtered ZnO Nano Films
(Kesan Keadaan Penyepuhlindupan Terhadap Morfologi Permukaan dan Kehabluran Filem Nano ZnO yang Dipercik)
J. Karamdel1,
2, C.F. Dee*,
1 & B. Yeop Majlis1
1Institute of Microengineering and Nanoelectronics (IMEN)
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor D.E., Malaysia
2Electrical Department, Faculty of
Engineering
Islamic
Azad University – South Tehran Branch
No.
209, North Iranshahr Ave, Tehran, Iran
Diserahkan: 23 Ogos 2010 / Diterima: 3 September 2010
ABSTRACT
The effects of annealing
parameters on crystallinity and surface morphology of RF sputtered zinc oxide nano films were
investigated. The structure and morphology of the nano films were dependent on temperature, gas flow rate and time of annealing. The
results from atomic force microscopy (AFM), field emission scanning
electron microscopy (FESEM) and X-ray diffraction (XRD)
showed smooth and uniform growth of c-axis orientation films with an average
grain sizes from 10 to 30 nm. Increments of the annealing temperature from 400
to 800°C led to bigger grain size, better crystallinity and also increase of the surface roughness. Moreover, the results showed that
the crystallinity was independent of the annealing
time up to 40 min after starting the annealing process. Increase in the
percentage of oxygen in the O/Ar (mixture of
annealing gases) from 50% to 100% results in no changes in AFM results,
but XRD revealed that the (100) peak intensity was decreased,
the position of (002) peak was slightly shifted towards higher angle and FWHM of (002) peak was improved.
Keywords: Annealing;
sputtering; ZnO nano film
ABSTRAK
Kesan pelbagai parameter penyepuhlindapan terhadap morfologi permukaan dan kehabluran bagi filem nano ZnO yang dipercik secara RF telah dikaji. Struktur dan morfologi nanofilem ini bergantung pada suhu, kadar aliran gas dan masa bagi proses sepuhlindapan. Keputusan daripada mikroskop daya atom (AFM), mikroskop elektron imbasan jenis pancaran medan (FESEM) dan pembelauan sinaran-X (XRD) menunjukkan filem-filem berorientasi pada paksi-c adalah licin dan seragam dengan butiran bersaiz purata daripada 10 ke 30 nm. Peningkatan suhu sepuh lindapan daripada 400 ke 800°C memberi saiz butiran yang lebih besar, kehabluran yang lebih baik namun menambahkan kekasaran permukaan. Hasil kajian juga menunjukkan kehabluran tidak bergantung kepada masa sepuh lindapan sehingga 40 min selepas permulaan proses penyepuhlindapan. Apabila ditambahkan peratusan oksigen dalam O/Ar (campuran gas penyepuhlindupan) daripada 50% menjadi 100%, didapati tiada perubahan pada keputusan AFM tetapi keputusan XRD menunjukkan bahawa keamatan puncak (100) telah berkurangan, kedudukan puncak (002) sedikit menganjak ke arah sudut lebih besar dan FWHM bagi puncak (002) bertambah baik.
Kata kunci: Nanofilem ZnO; percikan; sepuh lindap
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*Pengarang untuk surat-menyurat;
email: cfdee@vlsi.eng.ukm.my
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