Sains Malaysiana 41(3)(2012): 339–344

 

Effect of Annealing Temperature of Sol-Gel TiO2 Buffer Layer on Microstructure

and Electrical Properties of Ba0.6Sr0.4TiO3 Films

(Kesan Suhu Sepuhlindap Lapisan Penimbal TiO2 Sol-Gel Terhadap Mikrostruktur

dan Sifat Elektrik Filem Ba0.6Sr0.4TiO3)

 

N.B. Ibrahim*, E. Yusrianto, Z. Zalita & Z. Ibarahim

School of Applied Physics, Faculty of Science and Technology

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor D.E. Malaysia

 

Received: 9 March 2011 / Accepted: 19 September 2011

 

 

ABSTRACT

 

Ba0.6Sr0.4TiO3 (BST) thin films were prepared on TiO2 buffer layers. The buffer layers were prepared using sol-gel method, followed by annealing process at different temperature from 300 to 55oC with 50oC interval for 30 min in air. The microstructure and electrical properties of BST were then investigated. Increasing the annealing temperature increased. The buffer layer thickness BST films prepared on thicker buffer layer showed improved crystallinity. Without the buffer layer, BST crystallization cannot occur at 700oC. However with buffer layer, 700oC is sufficient for the process to occur. The BST grain size increased with the buffer grains increment. The existence of TiO2 buffer layer increased the current density. The dielectric constant, εr´ and dielectric loss were not affected much by the buffer layer except at frequency around 1 kHz that showed an increment in the εr’ value with the increment of the annealing temperature.

 

Keywords: Annealing; buffer layer; electrical properties; sol-gel

 

ABSTRAK

 

Filem nipis Ba0.6Sr0.4TiO3 (BST) telah disediakan di atas lapisan penimbal TiO2. Lapisan penimbal disediakan dengan kaedah sol-gel, diikuti dengan proses sepuh lindap pada suhu yang berbeza daripada 300 hingga 550oC dengan sela 50oC selama 30 min dalam udara biasa. Mikrostruktur dan sifat elektrik BST telah dikaji. Kenaikan suhu sepuh lindap meningkatkan ketebalan lapisan penimbal. Filem BST yang disediakan di atas lapisan penimbal yang lebih tebal mempunyai penghabluran yang lebih sempurna. Tanpa lapisan penimbal, penghabluran BST tidak boleh berlaku pada suhu 700oC, namun begitu dengan adanya lapisan penimbal, 700oC sudah mencukupi untuk membenarkan proses penghabluran berlaku. Saiz butiran BST meningkat dengan peningkatan butiran penimbal. Kewujudan lapisan penimbal TiO2 jugameningkatkan ketumpatan arus. Namun pemalar dielektrik, εr´ dan kehilangan dielektrik tidak begitu dipengaruhi oleh lapisan penimbal kecuali pada frekuensi lebih kurang 1 kHz yang menunjukkan penambahan εr’ dengan peningkatan suhu sepuh lindap.

 

Kata kunci: Lapisan penimbal; sepuh lindap; sifat elektrik; sol-gel

 

 

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*Corresponding author; email: baayah@ukm.my

       

 

 

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