CF4 / O2 / Ar 플라즈마에 대한 다양한 유리 조성의 플라즈마 저항 특성

Abstract

Recently, controlling the contamination from particles in the plasma etching process has become an important issue in the semiconductor or display industry. Plasma etching is accomplished with high density plasma because the development of the technology focuses on the competitiveness of the process cost. In this process, however, chamber surface exposed by repeated plasma etching chips off particles from the etching chambers so the demand for studies on plasma resistant materials has increased. Polycrystalline sintered ceramics such as Al2O3, YAlO3 and Y2O3 materials were typically used on plasma resistant materials. Even though they have excellent plasma resistant properties and mechanical properties along with chemical durability, contamination has remained a problem with the plasma etching process. To solve the problems with the plasma etching process, in this study we evaluated the plasma resistance of various glass compositions and four aluminosilicate oxide glasses containing nearly 40 mol% of alkaline earth elements. To evaluate the plasma resistance, we measured and observed the etch rate, surface roughness and microstructure and investigated the sublimation temperature of the fluoride compound of each element contained in the glass compositions to analyze the etching mechanisms of glass materials. In various glass compositions, each rate of BS, ZAP- system were measured as 140 ㎚/min that was higher than polycrystalline Al2O3 57 ㎚/min and sapphire 50 ㎚/min as a comparing materials. On the other hands, CAS and YAS- system were showed as 65 ㎚/min and 23 ㎚/min. In all kinds of glass compositions, Four alkaline earth aluminosilicate glasses were lower than 25 ㎚/min. Among them, CAS was showed lowest value of 13.24 ㎚/min. And surface roughness (Ra) was measured on Al2O3 3.32 ㎛, which has a highest variation either relatively other materials. other aluminosilicate contained alkaline earth oxide glasses were showed as approximate 0.05 ㎛. They are similar with polished surface roughness. Plasma resistant materials have a high density and sublimation temperature with fluoride increased the resistance of the plasma etching. Results of the measured plasma resistance confirmed that aluminosilicate oxide glasses containing alkaline earth elements were appropriate materials for plasma resistant materials: They had better resistance than existing materials.