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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
Diserahkan: 7 Januari 2012 / Diterima: 21 Mei 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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*Pengarang untuk surat-menyurat; email: noriah@utm.my
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