Sains Malaysiana 37(3): 285-288 (2008)

Nanoporous GaN Film Generated by Electro Chemical Etching

(Filem GaN Berliang Nano yang Disediakan Melalui Punaran Elektro Kimia) 

F.K. Yam,  Z. Hassan & K.M. Omar

School of Physics

Universiti Sains Malaysia

11800 Penang, Malaysia

ABSTRACT

This article reports on the studies of structural and optical properties of nanoporous GaN prepared by Pt assisted electro chemical etching. The porous GaN samples were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), and optical transmission (OT). SEM images liang indicated that the density of the pores increased with etching duration, however, the etching duration has no significant effect on the size and shape of the pores. AFM measurements exhibited that the surface roughness was increased with etching durations, however, for long etching duration, the increase of the surface roughness became insignificant. OT measurements revealed that the increase of pore density would lead to the reduction of light transmission. The studies showed that the porosity could influence the structural and optical properties of the GaN.

Keywords: Porous GaN; structural properties; optical properties

ABSTRAK

Artikel ini melaporkan kajian sifat-sifat struktur dan optik bagi GaN  nano liang yang disediakan dengan punaran elektro-kimia bantuan Pt. Sampel-sampel GaN berliang dikaji dengan mikroskopi elektron imbasan (SEM), mikroskopi (AFM) and pemancar optic (OT). Imej-imej SEM menunjukkan bahawa ketumpatan liang bertambah dengan masa punaran, tetapi, masa punaran tiada kesan ketara ke atas saiz dan bentuk liang. Ukuran AFM mendedahkan bahawa kekasaran permukaan  bertambah dengan masa punaran, bagaimanapun, bagi masa punaran yang lama, penambahan kekasaran permukaan tidak lagi bermakna. Ukuran OT menunjukkan bahawa penambahan ketumpatan liang boleh mengurangkan pemancaran cahaya. Kajian ini menunjukkan bahawa liang boleh mempengaruhi ciri-ciri struktur dan optik bagi GaN.

Kata kunci: GaN berliang; sifat-sifat struktur; sifat optik

RUJUKAN/REFERENCES

Canham, L. T. 1990. Silicon quantum wire array fabrication by electrochemical and chemical dissolution of wafers, Appl. Phys. Lett. 57: 1046-1048

Fauchet, P.M., Tsybeskov, L., Peng, C.,  Duttagupta, S. P., Von Behren, J.,  Kostoulas, Y., Vandyshev, J. M. V. & Hirschman, K.D.1995. Light-emitting porous silicon: materials science, properties, and device applications, IEEE J. Sel. Top. Quantum Electron. 1: 1126-1139.

Inoki, C. K., Kuan, T.S., Lee, C. D., Sagar, A. & Feenstra, R. M. 2002. Growth of GaN on Porous SiC Substrates by Plasma-Assisted Molecular Beam Epitaxy, Mater. Res. Soc. Symp. Proc. 722: K1.3.1.

Inoki, C. K., Kuan, T.S., Lee, C. D., Sagar, A.,  Feenstra, R. M., Koleske, D. D., Diaz, D. J., Bohn, P. W. & Adesida, I.  2003. Growth of GaN on porous SiC and GaN substrates, J. Electron. Mater. 32: 855-860.

Li, X., Kim, Y-W., Bohn P. W. & Adesida, I. 2002. In-plane bandgap control in porous GaN through electroless wet chemical etching, Appl. Phys. Lett. 80: 980-982.

Lin, V. S. Y., Motesharei, K., Dancil, K. P. S., Sailor, M. J. & Ghadiri, M. R.1997. A Porous Silicon-Based Optical Interferometric Biosensor, Science 278: 840-843.

Sohn, H., Letant, S., Sailor, M. J. & Trogler, W. C. 2000. Detection of fluorophosphonate chemical warfare agents by catalytic hydrolysis with a porous silicon interferometer, J. Am. Chem. Soc. 122: 5399-5400.