화학공학소재연구정보센터
Current Applied Physics, Vol.10, No.3, S435-S438, 2010
Effects of oxygen addition on electrical properties of silicon quantum dots/amorphous silicon carbide superlattice
It was found that the dark conductivity of a stoichiometric a-SiC thin film, which is used as barrier layers in a Si quantum dots superlattice (Si-QDSL), increased drastically after thermal annealing above 800 degrees C. This is due to the crystallization of an a-SiC phase in the films. To resolve this problem, CO(2) gas was introduced during the deposition of stoichiometric a-SiC thin films. As a result, the dark conductivity of the films annealed at either 900 or 1000 degrees C was reduced below 10 (9) S/cm, since the introduction of oxygen atoms into the films prevented the a-SiC phase from crystallizing during the annealing. O-containing Si-QDSLs were prepared and the dark conductivity of the O-containing Si-QDSLs was reduced in the range of 10 (6)-10 (7) S/cm and increased with increasing the diameter of Si-QDs, suggesting that the leakage in barrier layers was suppressed and the carrier transport through Si-QDs became predominant. (C) 2010 Elsevier B. V. All rights reserved.