Degradation by water vapor of hydrogenated amorphous silicon oxynitride films grown at low temperature

• Published in: Scientific reports Vol. 7; no. 1; pp. 14146 - 8
• Main Authors: Lee, Hyung-Ik, Park, Jong-Bong, Xianyu, Wenxu, Kim, Kihong, Chung, Jae Gwan, Kyoung, Yong Koo, Byun, Sunjung, Yang, Woo Young, Park, Yong Young, Kim, Seong Min, Cho, Eunae, Shin, Jai Kwang
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 26.10.2017; Nature Publishing Group
• Subjects: 639/301/357/537; 639/301/930/12; 639/925/930/12; Electron microscopy; Humanities and Social Sciences; Hydrogenation; Low temperature; multidisciplinary; Oxygen; Porosity; Science; Science (multidisciplinary); Silicon; Spectroscopy; Temperature effects; Transmission electron microscopy; Water vapor
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-14291-2

We report on the degradation process by water vapor of hydrogenated amorphous silicon oxynitride (SiON:H) films deposited by plasma-enhanced chemical vapor deposition at low temperature. The stability of the films was investigated as a function of the oxygen content and deposition temperature. Degradation by defects such as pinholes was not observed with transmission electron microscopy. However, we observed that SiON:H film degrades by reacting with water vapor through only interstitial paths and nano-defects. To monitor the degradation process, the atomic composition, mass density, and fully oxidized thickness were measured by using high-resolution Rutherford backscattering spectroscopy and X-ray reflectometry. The film rapidly degraded above an oxygen composition of ~27 at%, below a deposition temperature of ~150 °C, and below an mass density of ~2.15 g/cm 3 . This trend can be explained by the extents of porosity and percolation channel based on the ring model of the network structure. In the case of a high oxygen composition or low temperature, the SiON:H film becomes more porous because the film consists of network channels of rings with a low energy barrier.