Sains Malaysiana 42(2)(2013): 219–222

Aluminium-Induced Crystallization of Silicon Thin Film by Excimer Laser Annealing

(Penghabluran Teraruh Aluminium Terhadap Saput Tipis Silikon Melalui Sepuhlindap Laser Eksimer)

Siti NoraizaAb Razak & Noriah Bidin*

Jabatan Fizik, Fakulti Sains, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia

Received: 7 January 2012 / Accepted: 21 May 2012

ABSTRACT

Polycrystalline silicon (poly-Si) film was fabricated by indirect process of re-crystallization of amorphous silicon (a-Si) thin film. This enhancement process is important to determine the performance of silicon thin film (STF). In this attempt, a fundamental study was carried out to enhance the crystallization of aluminium doped silicon thin film. An a-Si thin film was prepared by low pressure physical vapour deposition (PVD) and doped with 10% aluminium. The aluminium-induced crystallization (AIC) process was carried out in two sequences steps. Firstly, the amorphous film was annealed by using conventional heat treatment at operating temperature of 350°C. Secondly, the poly-Si underwent excimer laser anneling (ELA). The microstructure of thin film was analyzed using Atomic Force Microscope (AFM). The results showed that, the grain size of the a-Si film is increased with the energy density of the excimer laser. The optimum grain size obtained is 129 nm corresponding to energy density of 356 mJ cm^-2

.

Keywords: Aluminium; amorphous silicon; crystallization; excimer laser annealing; super lateral growth

ABSTRAK

Saput polihablur silikon (poly-Si) disediakan melalui proses penghabluran semula saput tipis silikon amarfos (a-Si) secara tidak terus. Proses peningkatan ini adalah penting untuk menentukan prestasi saput tipis silikon (STF). Kajian asas telah dilakukan untuk meningkatkan penghabluran saput tipis silikon terdop aluminium. Saput tipis silikon amorfus disediakan menggunakan pemendapan wap fizikal bertekanan rendah (PVD) dan didop dengan 10% aluminium. Prosesaruhan aluminium-teraruh (AIC) dijalankan dalam dua langkah berturutan. Pertama, saput amorfus disepuhlindap menggunakan pemanasan konvensional pada suhu operasi iaitu 350°C. Kedua, poli-Si disediakan melalui sepuhlindap laser eksimer (ELA). Struktur mikro saput tipis dianalisis menggunakan mikroskop daya atom (AFM). Keputusan menunjukkan bahawa, saiz butiran saput a-Si meningkat dengan meningkatnya ketumpatan tenaga laser eksimer. Saiz butiran optimum yang diperoleh ialah 129 nm bersamaan dengan 356 mJ cm^-2

ketumpatan tenaga.

Kata kunci: Aluminium; penghabluran; sepuhlindap laser eksimer; silikon amorfus; pertumbuhan sisi super

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*Corresponding author; email: noriah@utm.my