The Growth of Silicon Nitride Crystalline Films Using Microwave Plasma Enhanced Chemical Vapor Deposition


Book Description

Crystalline thin films of silicon nitride have been grown on a variety of substrates by microwave plasma-enhanced chemical vapor deposition using N2, O2, and CH4 gases at a temperature of 800 deg C. X-ray diffraction and Rutherford backscattering measurements indicate the deposits are stoichiometric silicon nitride with varying amounts of the alpha and beta phases. Scanning electron microscope imaging indicates beta-Si3N4 possesses six-fold symmetry with particles size in the submicron range. In one experiment, the silicon necessary for growth comes from the single crystal silicon substrate due to etching/sputtering by the nitrogen plasma. The dependence of the grain size on the methane concentration is investigated. In an another experiment, an organo- silicon source, methoxytrimethylsilane, is used to grow silicon nitride with controlled introduction of the silicon necessary for growth. Thin crystalline films are deposited at rates of 0.1 micrometer/hr as determined by profilometry. A growth mechanism for both cases is proposed.













Characteristics of Silicon Nitride Deposited by VHF (162 MHz)-plasma Enhanced Chemical Vapor Deposition Using a Multi-tile Push–pull Plasma Source


Book Description

Abstract: To prevent moisture and oxygen permeation into flexible organic electronic devices formed on substrates, the deposition of an inorganic diffusion barrier material such as SiN x is important for thin film encapsulation. In this study, by a very high frequency (162 MHz) plasma-enhanced chemical vapor deposition (VHF-PECVD) using a multi-tile push–pull plasma source, SiN x layers were deposited with a gas mixture of NH3 /SiH4 with/without N2 and the characteristics of the plasma and the deposited SiN x film as the thin film barrier were investigated. Compared to a lower frequency (60 MHz) plasma, the VHF (162 MHz) multi-tile push–pull plasma showed a lower electron temperature, a higher vibrational temperature, and higher N2 dissociation for an N2 plasma. When a SiN x layer was deposited with a mixture of NH3 /SiH4 with N2 at a low temperature of 100 °C, a stoichiometric amorphous Si3 N4 layer with very low Si–H bonding could be deposited. The 300 nm thick SiN x film exhibited a low water vapor transmission rate of 1.18 × 10 −4 g (m 2 · d) −1, in addition to an optical transmittance of higher than 90%.