Abstract
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/cm3. 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.
Highlights
The degradation by water vapor of hydrogenated amorphous silicon oxynitride film deposited by PECVD at low temperature was investigated as a function of the oxygen concentration and deposition temperature
The TEM and TEM-EDS observations showed no pinholes or grains, so the water vapor penetrated by diffusion through interstitial paths and nano-defects
A porous structure formed with nano-voids of various sizes through which water vapor could penetrate
Summary
A SiON film deposited at low temperature oxidizes very when exposed to water vapor. The SiN:H sample without oxygen content, as presented in 0 sccm of Table 1, contained a high concentration of hydrogen atoms at 26.8 at%; this included at least 17.8 at% of N–H bonds[23] It should be composed of porous structures, and the density was really only 2.25 g/cm[3]. The fully oxidized thicknesses changed very dramatically when the deposition temperature was decreased from 150 °C to 100 °C, even though the difference in concentrations was small This trend means that the film degradation with the PCT approached a critical temperature. The PCT time was taken for a long time, the thickness of fully oxidized layers slightly increased and the water vapor was well blocked
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
