Formation of High-Density Pt Nanodots on SiO 2 Induced by Millisecond Rapid Thermal Annealing Using Thermal Plasma Jet for Floating Gate Memory

We formed nanometer-scale Pt dots on SiO 2 by thermal plasma jet (TPJ) irradiation and demonstrated the feasibility of TPJ millisecond annealing for controlling the areal density of the dots. 2–10-nm-thick Pt/quartz was exposed to an Ar plasma jet at peak temperatures of 455–695 °C for a duration of 1–2 ms. When the Pt/quartz was annealed by TPJ irradiation without any extra heating, the Pt nanodot density was controlled in the range of 7.8 ×10 10 to 2.0 ×10 11 cm -2 by changing the annealing temperature and the number of irradiations. These results imply that ultra-rapid annealing using a TPJ plays an important role in enhancing the surface migration of Pt atoms in order to reduce the interface energy of Pt/quartz.