Investigation of a nanocrystalline silicon phase embedded in SiO x thin films grown by pulsed laser deposition

• Published in: Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures 2005-03, Vol.23 (2), p.519-524
• Main Authors: Fazio, Enza, Barletta, Enrico, Barreca, Francesco, Neri, Fortunato, Trusso, Sebastiano
• Format: Article
• Language: English
• ISSN: 0734-211X; 1520-8567; 2327-9877
• DOI: 10.1116/1.1880252

The formation of nanocrystalline silicon clusters in SiO x thin films has been investigated by means of micro-Raman and Fourier transform infrared spectroscopic techniques. The samples were deposited, by means of pulsed laser ablation of a silicon target in a controlled oxygen gas environment, on substrates heated up to 883 K. Experimental results show that, by appropriately varying the deposition parameters, it is possible to achieve a fully coordinated silicon dioxide phase with the contemporary development of a nanometer-sized crystalline silicon phase and/or an amorphous one. Comparison between the effect of a relatively high substrate temperature and of a post-deposition annealing treatment have been exploited. From the line-shape analysis of the silicon TO vibrational mode Raman band, crystalline silicon volume fractions up to 90% have been estimated, while the nanocrystalline cluster sizes remained almost constant around 3.5 nm. A good agreement between our results and the predictions of silicon nanoclusters formation by a silicon atom diffusion-controlled mechanism has been found.