Nano Archive

Surface effects on the photoluminescence of Si quantum dots

Wang, Chiang-Jing and Tsai, Meng-Yen and Chi, Cheng Chung and Perng, Tsong-Pyng (2009) Surface effects on the photoluminescence of Si quantum dots. Journal of Nanoparticle Research, 11 (3). pp. 569-574.

Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.

Official URL: http://www.springerlink.com/content/y24140r1315820...

Abstract

Si quantum dots (SiQDs) with sizes ranging from 5 to 20 nm were fabricated by vapor condensation. They showed red photoluminescence (PL) in vacuum with the peak located at around 750 nm. After the specimen was exposed to air, the PL intensity became higher, and continued to increase during the PL test with a cycling of vacuum-air-vacuum. In pure oxygen, the PL intensity exhibited an irreversible decrease, while in nitrogen a smaller amount of reversible increase of PL intensity was observed. Furthermore, the PL intensity exhibited a remarkable enhancement if the SiQDs were treated with water. With HF treatment, the PL peak position showed a blue-shift to 680 nm, and was recovered after subsequent exposure to air. Si–O–H complexes were suggested to be responsible for this red luminescence. The irreversible decrease of PL intensity due to oxygen adsorption was speculated to be caused by the modification of chemical bonds on the surface. In the case of nitrogen adsorption, the PL change was attributed to the surface charging during adsorption.

Item Type:Article
ID Code:4249
Deposited By:Prof. Alexey Ivanov
Deposited On:16 Mar 2009 09:42
Last Modified:08 May 2009 23:30

Repository Staff Only: item control page