Microscopic structural randomness in SiO2, a typical electrical insulating material, was evaluated by observing the decay profile of the photoluminescence due to the oxygen vacancy (≡Si-Si≡). As the samples with different degrees of randomness, an ionimplanted thermal SiO2 film, SiO2 films formed by plasma-enhanced chemical vapor deposition of tetraethoxysilane with and without doped fluorine, a buried oxide film prepared with the method of separation by ion-implanted oxygen (SIMOX), and a bulk silica glass prepared by the soot-remelting method were tested. By analyzing the decay profile with a stretched-exponential function, it was found that the deviation of the decay profile from a single exponential function is larger in the sample whose structural randomness is presumed to be larger from the measurements of infrared absorption and the chemical etch rate in HF solution.
J-STAGEがリニューアルされました！ https://www.jstage.jst.go.jp/browse/-char/ja/
