A Study on the Removal of Silicon Native Oxide on a Silicon Surface using UV-excited F₂/H₂and it's Application of Contact Process = UV-excited F₂/H₂를 이용한 실리콘 자연산화막 제거와 컨택 공정에의 적용

국문 초록 (Abstract)

UV-excited F₂+ H₂를 이용한 건식 세정에 있어서, 자연 산화박의 에칭 메카니즘과 선택 에칭이 실리콘 웨이퍼상에 형성한 PSG, BSG, TEOS, 열산화막 등을 사용하여 조사되었다. UV-excited F₂+ H₂가 UV/f₂처리보다 표면요철이 작고, HF습식 세정과 거의 같은 정도임을 알 수 있었다. 도한 포토네지스트 선패턴을 갖는 여러 가지 산화막의 에칭효과로부터 컨택 홀내에 자연산화막의 선택에칭을 위한 임계점을 찾아내었다. 결과적으로, UV-excited F₂+ H₂를 이용한 건식 세정으로 컨택 홀내의 자연 산화막을 제거할 수 있슴이 켈빌저항의 강소로부터 확인되었다. 기존의 HF습식 세정보다 캘빈저항이 더 작음을 알 수 있었다.

다국어 초록 (Multilingual Abstract)

In the UV-excited F₂+ H₂ dry cleaning, the etching mechanism and selective etching of silicon native oxide were investigated using PSG, BSG, TEOS and thermal oxide film on silicon wafers. It was discovered that UV-excited F₂+H₂ treatment leads to relatively lower surface roughness than UV/F₂ treatment.
Besides, the surface roughness after UV-excited F₂+H₂ treatment was similar with after HF wet cleaning. And we found the critical point of selective etching for silicon native oxide in contact holes from the etching effect of various oxide films above with PR lind/spacing pattern. As a result, the removal of silicon native oxide in contact holes after UV-excited F₂+H₂dry cleaning was confirmed by the reduction of Kelvin resistance. We confirmed that Kelvin resistance after UV-excited F₂+H₂ treatment was lower than after conventional HF wet cleaning.

목차 (Table of Contents)

• I.Introduction
• II.Experiment
• III.Results and Discussion
• 1.UV effect and temperature effect
• 2.Surface analysis
• 3.Selective removal of silicon native oxide
• 4.Electrical measurement
• IV.Conclusion