Sains Malaysiana 42(9)(2013): 1333–1337

Preparation of Porous Si (100) for Overgrown Cubic Layer: Morphological Investigation

(Penyediaan Si (100) Berliang untuk Pertumbuhan Lapisan Atas Kubik: Kajian Morfologi)

M.E.A. Samsudin¹, M. Ikram Md Taib¹, N. Zainal¹*, R. Radzali^{2 3}, S. Yaakob⁴ & Z. Hassan¹

¹Nano-optoelectronics Research and Technology, School of Physics, Universiti Sains Malaysia

11800, Penang, Malaysia

²Nano-optoelectronics Research and Technology, School of Physics, Universiti Sains Malaysia

11800, Penang, Malaysia

³Fakulti Kejuruteraan Elektrik Universiti Teknologi MARA 40450 Shah Alam, Selangor, D.E. Malaysia

  ⁴School of Chemical Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia

Diserahkan 19 Disember 2012 /Diterima: 19 Januari 2013

ABSTRACT

A number of n-type Si (100) samples were prepared into porous structures via electrochemical etching process, using an electrolyte solution; HF and ethanol. The morphological properties of the samples were observed under scanning electron microscope measurement. The results showed that the pore density, pore uniformity distribution and pore size of the porous Si samples increased with time of etching. In the next stage, H₂O₂ was introduced into the electrolyte solution in order to investigate its effect on the morphological properties of the porous Si. From the experiment, we found that H₂O₂ gave finer porous structure with highly symmetrical cubic shape on the surface. Besides, H₂O₂ promoted smoother surface of the pore walls. Hence, the results showed that such porous Si structure could be used as a better substrate for the subsequent layer, in particular for the growth of cubic material.

Keywords: Hydrogen peroxide; morphological properties; porous silicon

ABSTRAK

Beberapa jenis-n Si (100) sampel telah disediakan dalam bentuk struktur berliang melalui proses punaran elektrokimia, menggunakan larutan elektrolit; HF dan etanol. Sifat morfologi sampel tersebut telah diperhatikan di bawah mikroskop elektron imbasan. Keputusan pengukuran tersebut menunjukkan bahawa ketumpatan liang, keseragaman taburan liang dan saiz liang bagi sampel Si berliang meningkat dengan masa punaran. Pada peringkat seterusnya, H₂O₂ telah dicampurkan ke dalam larutan elektrolit tersebut untuk mengkaji kesannya terhadap sifat morfologi Si berliang. Daripada experimen tersebut, kami mendapati bahawa H₂O₂ memberikan struktur berliang yang lebih halus dengan bentuk kubik yang bersimetri tinggi pada permukaan. Selain itu, H₂O₂ turut menyebabkan permukaan dinding liang menjadi lebih licin. Justeru, hasil kajian tersebut mencadangkan bahawa struktur Si berliang seperti ini boleh digunakan sebagai substrat yang lebih baik untuk lapisan seterusnya, khususnya untuk pertumbuhan bahan kubik.

Kata kunci: Hidrogen peroksida; sifat morfologi; silicon berliang (100)

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*Pengarang untuk surat-menyurat; email: norzaini@usm.my