According to the design rule shrinkage, more precise control of mask CD, including mean to target and uniformity, is
required in lithography process. Since dry etching is one of the most critical processes to determine CD qualities in
photomask, optical emission spectroscopy (OES) to monitor plasma status during dry etching process could be useful.
However, it is not possible to obtain distributional information of plasma with a conventional OES tool because the OES
acquires totally integrated signals of light from the chamber. To overcome the limit of OES, we set up a spatially
resolved (SR)-OES tool and measure the distribution of radicals in plasma during dry etch process. The SR-OES consists
of a series of lenses, apertures, and a pinhole as a spatial filter which enable us to focus on certain area in the chamber, to
extract the emitted light from plasma, and to perform the spectroscopic analysis. The Argon based actinometry combined
with SR-OES shows spatially distinguished peaks related to the etch rate of Chromium on photomask. In this paper, we
present experimental results of SR-OES installed on a commercial photomask dry etcher and discuss its practical
effectiveness by correlation of the results with chamber etch rate.
The electronics fabrication without using conventional deposition and photolithography has attracted an intense interest in the modern technology. The direct metal pattering based on the laser local sintering of nano ink is one of the alternative manufacturing methods. In this sintering process, some researchers have shown the mechanism of the heating particle.
In this paper, we discuss the theoretical analysis of sintering process about silver and copper nanoparticles. For analyzing the sintering process, we use Shi’s model to calculating the melting temperature and surface melting temperature with variation of the particle size. The absorption cross section with respect to wavelength of laser and particle size is calculated by Mie theory. From the results, we suggest the minimum energy per unit area of laser with respect to particle size and wavelength of the laser for the sintering process. These results suggest that the longer the wavelength of the laser, the higher minimum energy for sintering process in copper case. In the silver case, the wavelength of the laser has to be close to 350 nm which is near to the surface plasmon resonance frequency of the silver for minimum energy per unit area.