In semiconductor industry, cluster tools are widely used in wafer manufacturing, especially in wafer fabrication. Many previous researches have dealt with conventional architecture of cluster tools, which are single-arm and dual-arm. Recently, a new cluster tool architecture has been introduced to improve productivity and quality of wafers. The new architecture is called independent dual-arm.
Previously, three independent dual-arm robot sequences, which are Modified Swap, Dual Backward, and Disjunct Backward, have been proposed. However, independent dual-arm cluster tools have never been studied with chamber cleaning operation. By extending the three independent dual-arm robot sequences, we propose Modified Swap(z), Dual Backward(z), and Disjunct Backward(z) sequences that allow partial loading for parallel chambers, where vector z specifies how many chambers z$_i$ of each process step i are kept empty for cleaning. We then examine three sequences based upon cycle time and wafer delay.
We propose a new robot sequence, called Hybrid Backward(s,z). The sequence optimizes both cycle time and wafer delay. We verify by graph analysis and optimal results given by MIP model.
반도체 산업에서는 클러스터 장비가 널리 쓰인다. 주로 한팔, 고정된 양팔 장비가 많이 쓰였으나 최근 들어 독립된 양팔 클러스터 장비가 많이 쓰이고 있다. 또한, 클리닝 작업에서는 병렬 챔버에서 부분 로딩이 전체 로딩보다 효과적임이 알려져 있다. 본 연구에서는 기존 독립된 양팔 클러스터 장비에 부분 로딩을 적용시켜 사이클 타임과 웨이퍼 지연을 분석하였다. 그리고 새로운 로봇 시퀀스를 제안한다. 새로운 로봇 시퀀스는 사이클 타임과 웨이퍼 지연 모두를 최적화 시킨다.
