Ion beam synthesis of germanium nanostructures

✍ Scribed by Kapil U. Joshi; A.M. Narsale; D. Kanjilal; T.N. Warang; T.K. Gundurao; D.C. Kothari

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 312 KB
• Volume: 203
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2009.02.040

✦ Synopsis

Si and Ge nanocrystals embedded in SiO 2 have attracted much attention due to their possible application in integrated optoelectronic devices. Ion beam mixing of Ge film into fused silica to form Ge nanoparticles is one of the possible methods to controllably produce embedded nanoclusters. In this work, Ge nanocrystals in fused silica were formed by defect induced nucleation and ion beam mixing. In our experiment, we have created defects in fused silica using 200 keV Ar ions with different fluences ranging from 1 × 10 15 to 2 × 10 16 ions/cm 2 (pre-mixing irradiation). Ge film (20 nm) was then deposited on it and ion beam mixed using 230 keV Ar ions at a fluence of 2 × 10 16 ions /cm 2 . The Ge-SiO 2 composite films were characterized using UVvisible and Micro-Raman spectroscopy. UV-visible spectra showed variation in absorption band gap with ion beam fluence used for pre-mixing irradiation. Micro-Raman spectra showed formation of Ge nanoparticles in SiO 2 .