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. Karamdel^{1, 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