Microstructure and photoluminescence of CdS-doped silica films grown by RF magnetron sputtering

作者：Rolo AG^*; Stepikhova MV; Filonovich SA; Ricolleau C; Vasilevskiy MI; Gomes MJM

来源：Physica Status Solidi B-Basic Solid State Physics, 2002, 232(1): 44-49.

DOI：10.1002/1521-3951(200207)232:1<44::AID-PSSB44>3.0.CO;2-4

Silica films containing CdS nanometer-sized particles with semiconductor contents of 1-10% were produced by radio-frequency magnetron sputtering at room temperature with subsequent annealing. The mean diameter of the CdS nanocrystals (NCs) varied between 4 and 6 nm, with narrow size distribution. High-resolution transmission electron microscopy images obtained for low-semi conductor-fraction samples showed quite a homogeneous NC distribution inside the silica matrix while the high-concentration samples showed an agglomeration of NCs in a columnar structure The observed photoluminescence (PL) bands were correlated with the semiconductor concentration. Two intense PL bands, one near the band-gap energy and the other in the red, were ob served at low temperature for samples with low CdS fraction. The high-energy band was found to be Stokes shifted by some 200 meV with respect to the absorption edge at room temperature. Th samples with high CdS fraction only displayed a broad red emission band, which was attributed to interface states.

• 出版日期2002-7