Raman spectroscopy and morphology investigation of porous GaAs
|Valeriy V. Kidalov 2, George A. Suckach 1, Lotfy Beji 3, Andrey S. Revenko 2, Agnieszka Bajda 2, Yuri Yatsenko 2|
1. Institute for Physics of Semiconductors of NAS of Ukraine, 45 Prospekt Nauki, Kyiv 03028, Ukraine
Porous GaAs attract attention in recent years as promising substrate for GaN epitaxy for the purpose of minimizing some negative effects due to large lattice mismatch and difference in thermal expansion coefficient of GaAs and GaN, that usually leads to high strain and high defects density in GaN/GaAs structures. First attempts of using porous GaAs as a substrate for GaN epitaxy was reported in [1,2].
Samples of porous GaAs was obtained by anodic electrolytic treatment of (111)B plane of n-GaAs with concentration of Si 2*1016 cm-3 . With the aim to surface cleaning GaAs samples was preliminary treated in acetone, propanol, ethanol and washed in distillery water and after that samples was dried in flow of N2. The back of samples was mapped by ohmic contact. Platinum plate was as a second electrode. Electrolytic etching process was carrying out in HF + ethanol solution (of differential concentration). After etcing GaAs samples was washed in deionized water and dry in N2 flow.
From Raman spectroscopy and scanning electron microscopy investigation the size of GaAs nanocrystallites was determined, its value was estimated about 10-100 nm. Estimation of the size of nanocryslallites in por-GaAs both by Raman shift and scanning electron microscopy gives approximately the same values.
1. V.V. Mamutin, V.P. Ulin, V.V. Tret’yakov. Tech. Phys. Lett. 25, 1 (1999)
2. V. V. Kidalov, G. A Sukach, A. S. Revenko, A.D. Bajda. Phys. Stat. Sol. 1-5, 1345 (2005).
3. L. Beji, L. Sfaxi, B. Ismail, A. Missaoui, F. Hassen, H. Maaref, H. Ben Ouada. Physica E 25, 636 (2005).
Presentation: poster at E-MRS Fall Meeting 2005, Symposium F, by Valeriy V. Kidalov
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-08-03 12:28 Revised: 2009-06-07 00:44