Novel Method for Site-Controlled Surface Nanodot Fabrication by Ion Beam Synthesis

• Published in: Nano letters Vol. 5; no. 4; pp. 771 - 776
• Main Authors: Buckmaster, Ryan, Hanada, Takashi, Kawazoe, Yoshiyuki, Cho, Meoung-whan, Yao, Takafumi, Urushihara, Nobuaki, Yamamoto, Akira
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01-04-2005
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Defects and impurities in crystals; microstructure; Doping and impurity implantation in other materials; Exact sciences and technology; Materials science; Nanoscale materials and structures: fabrication and characterization; Physics; Quantum dots; Structure of solids and liquids; crystallography; Atomic force microscopy; Scanning electron microscopy; Vacuum annealing; Gallium; Ion implantation; Inorganic compounds; Nucleation; Catalysts; Quantum dots; Physical radiation effects; Binary compounds; Experimental study; Focused ion beam technology; AES; Self-assembly; Silicon oxides; Morphology; Nanostructured materials
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl048044j

By using a Ga FIB system to spatially control the implantation of Ga into SiO2 followed by vacuum annealing, we have fabricated self-assembled surface Ga nanodots with a high degree of control of nucleation location. The morphology of the Ga nanodots is closely related to Ga dose, showing a critical dose needed for nucleation that results in Ga nanodot formation just below the surface, while at higher doses Ga nanodots form on the surface as metallic Ga droplets. Possible applications include defining nucleation sites for subsequent growth, use as Ga source for GaN or GaAs quantum dots, or as catalyst for nanowire growth.