Jung-Hyun Hwang

High resolution digital zoom using temporal IIR filter

We propose a set of algorithms for improving the resolution of image sequences, which are assumed to have a greater amount of information than a 2-dimensional still image. The proposed algorithms can be the theoretical basis for 3-dimensional interpolation of dynamic image sequences. More specifically, motion detection in sub-pixel level and IIR filtering along the time axis are proposed for high resolution B image magnification as well as digital image stabilization. Experimental results using real image sequence are presented which demonstrate the validity of the proposed method.

New approach for quartz dry etching using hardmask for sub-90-nm photomask technology

Quartz dry etching is critical to realize the resolution enhancement technology (RET) mask, such as chromeless phase lithography (CPL) mask, alternating phase shift mask, and RIM type phase shift mask. Quartz etching is one of challenging processes in photomask manufacturing due to the absence of etch stopper. The requirements of quartz etching are sidewall angle, phase uniformity, depth linearity, and micro/macro loading effect in wide range of feature sizes. In this paper, we will discuss the improvement of quartz dry etching using Cr hardmask without any hardware modifications. We can control the tendency of phase uniformity across mask surface in convex or concave curvature with nearly vertical sidewall angle. Two-step quartz etching recipe, which consists of two kinds of sub-etching recipe, is introduced to meet the phase uniformity and quartz profile at the same time. We have optimized quartz dry etching with vertical sidewall angle, low depth uniformity, and low micro/macro loading effect.