Deposition of silicon dioxide films with a non-equilibrium atmospheric-pressure plasma jet

Abstract

Silicon dioxide films were grown using an atmospheric-pressure plasma jet that was produced by flowing oxygen and helium between two coaxial metal electrodes that were driven by 13.56 MHz radio frequency power. The plasma exiting from between the electrodes was mixed with tetraethoxysilane (TEOS), and directed onto a silicon substrate held at 115-350 • C. Silicon dioxide films were deposited at rates ranging from 20 ± 2 to 300 ± 25 nm min −1. The deposition rate increased with decreasing temperature and increasing TEOS pressure, oxygen pressure and RF power. For the latter two variables, the rate increased as follows: Rd ∝ P 0.3 O 2 (RF) 1.4. Films grown at 115 • C were porous and contained adsorbed hydroxyl groups, whereas films grown at 350 • C were smooth, dense and free of impurities. These results suggest that the mechanism in the atmospheric pressure plasma is the same as that in low-pressure plasmas.

Optical Diagnostics of Micro Discharge Jets

“…Many experiments demonstrating the surface modification abilities of the APPJ have been performed by Selwyn and co-workers [9][10][11].…”

Impact on the Gas Barrier Property of Silicon Oxide Films Prepared by Tetramethylsilane-Based PECVD Incorporating with Ammonia

“…2017, 7, 56 7 of 11 from the film synthesized using the TMS-O 2 -NH 3 gas mixture at a gas flow ratio of 0.5 (Figure 6b) which also resulted in the lowest surface roughness. As quoted from the previous reports [39][40][41], the coverage of the voids resulted from the terminated bonds in the Si-O-Si networks and/or the excess oxygen contents to cause the compressive stress residing in the deposited film which was most likely responsible for the appearance of these protrusions. In addition, the additive terminated bonds associated with the Si(CH 3 ) x species and/or the introduced nitrogen contents in the film deposited using the TMS-NH 3 gas mixture were ascribed to result in the dot-sized protrusions.…”

Nonequilibrium Atmospheric Plasma Deposition

“…Such processes are particularly promising to treat complex 3D objects by mounting the plasma source on a robot. Table 3 shows a list of works performed with millimetric jets and torches for PECVD at atmospheric pressure (Ref [76][77][78][79][80][81][82][83][84][85][86]. Historically, plasma micro-torches were proposed with thermal plasmas (Ref 87-89) rather than with nonequilibrium plasmas.…”