Plasmonic plasma process for low temperature growth of high-quality ultra-thin dielectric films

The discharge plasma can be regarded as a vibration phenomenon of electrons in the gas phase, and high-energy electrons cause a non-equilibrium reaction. Similarly, the electrons in the gold nanoparticles also vibrate due to the electric field to form plasmons, and the high-energy electrons can cause a non-equilibrium reaction. In this study, gold nanoparticles are placed on a silicon substrate exposed to low-pressure reactive plasma, and plasmons generated by light irradiation and radical atoms supplied by the plasma realize oxidation and nitridation of the silicon substrate in an environment extremely close to room temperature. Gold nanoparticles are formed by vapor deposition, with an average particle size of 6 nm. 1 Pa pure oxygen or nitrogen plasma is formed by inductively coupled plasma. Infrared or green light is suitable for plasmon excitation. Space potential control with stainless steel mesh electrodes was used to protect the nanoparticles. Insulating films were formed by a 10-minute treatment at room temperature and were evaluated by mercury probe method. The film quality was found to be equivalent to that of an ideal thermal oxide film or SiON film, demonstrating the significance of plasmon-based plasma processes.