Pellicle is defined as a thin transparent film stretched over an aluminum (Al) frame that is glued on one side of a photomask. As semiconductor devices are pursuing higher levels of integration and higher resolution patterns, the cleaning of the Al flame surface is becoming a critical step because the contaminants on the Al flame can cause lithography exposure defects on the wafers. In order to remove these contaminants from the Al frame, a highly concentrated nitric acid (HNO3) solution is used. However, it is difficult to fully remove them, which results in an increase in the Al surface roughness. In this paper, the pellicle frame cleaning is investigated using various cleaning solutions. When the mixture of sulfuric acid (H2SO4), hydrofluoric acid (HF), hydrogen peroxide (H2O2), and deionized water with ultrasonic is used, a high cleaning efficiency is achieved without HNO3. Thus, this cleaning process is suitable for Al frame cleaning and it can also reduce the use of chemicals.

As the fabrication technology used in FPDs(flat-panel displays) advances, the size of these panels is increasing and the pattern size is decreasing to the um range. Accordingly, a cleaning process during the FPD fabrication process is becoming more important to prevent yield reductions. The purpose of this study is to develop a FPD cleaning system and a cleaning process using a two-phase flow. The FPD cleaning system consists of two parts, one being a cleaning part which includes a two-phase flow nozzle, and the other being a drying part which includes an air-knife and a halogen lamp. To evaluate the particle removal efficiency by means of two-phase flow cleaning, silica particles 1.5μm in size were contaminated onto a six-inch silicon wafer and a four-inch glass wafer. We conducted cleaning processes under various conditions, i.e., DI water and nitrogen gas at different pressures, using a two-phase-flow nozzle with a gap distance between the nozzle and the substrate. The drying efficiency was also tested using the air-knife with a change in the gap distance between the air-knife and the substrate to remove the DI water which remained on the substrate after the two-phase-flow cleaning process. We obtained high efficiency in terms of particle removal as well as good drying efficiency through the optimized conditions of the two-phase-flow cleaning and air-knife processes.

본 연구는 직전 교사교육의 질적 향상에 대한 필요성을 인식하고, 한국과 중국 교원양성대학의 교육과정을 비교· 분석하여 양국 교사교육의 특징을 이해하고 개선을 위한 시사점을 제시하는 데 목적이 있다. 이를 위하여 교원양성대학의 교육목표, 현행 교육과정의 편성·운영체제와 각 영역별 교과목에 대해 비교·분석하였다. 한국과 중국은 모두 목적형의 교원양성방식을 취하고 있으며 목표의 진술, 교육과정의 편성과 운영에서 많은 공통점을 보이고 있다. 차이점으로는 총 이수학점에서 중국은 한국보다 더 많은 학점을 요구하고 있는 반면에 전체이수학점 중 자유선택영역의 이수학점은 한국의 대학에 비해 훨씬 적었다. 또한 각 영역 학점의 배분에서 중국은 교양영역과 교과내용학 영역에 상대적으로 많은 학점을 두고 있다. 따라서 교사의 전문성 향상을 위한 교육과정의 편성에서 교육학 및 교과교육학 영역에 더 많은 관심을 가지고 효과적인 교사 양성을 위한 교육과정에 대한 이론적 탐구가 지속적으로 이루어지는 것이 바람직하다.