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
Received:
23 August 2010 / Accepted: 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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*Corresponding
author; email: cfdee@vlsi.eng.ukm.my
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