As devices shrink, new materials and new stacked structures are being introduced to improve performance and overcome structural limitations. For memory devices, the higher stacked structure, which was mainly used in Flash devices, is being extended to Dram devices. The structure for logic devices is transitioning from planar, Finfet and GAA to Forksheet and CFET.In order to develop processes for a future device, the cleaning process has also become increasingly sophisticated and difficult. In particular, the requirements for fundamental cleaning techniques such as highly selective and narrow gap etching, small particle removal and extreme uniformity control are being pushed to the limit.In this presentation, we will review trends in device roadmaps and suggest new cleaning technologies needed for future devices. New chemicals with inhibitors and dry cleaning processes using radical or etching gas are being evaluated for highly selective etching of materials with different Ge content, such as SiGe 5~50%. New concepts will be suggested for small particle removal without pattern damage using polymers and for selective deposition by Wet SAM (Self -Assembly Monolayer) which could have various applications. In terms of small particle removal, we use polymers that can be attached to small particles, like sticky materials, which remove them without any other residues. In this process, it is important to remove small particles without causing any other damages to the pattern. For SAM, it can chemically adsorb in the area where material does not want to be deposited and stays during subsequent deposition, resulting in a selective deposition. Any SAM after deposition should be removed by plasma treatment.In addition, reclaimable chemicals have been expanding to promote environmental sustainability and cost efficiency. To achieve this, a real-time chemical analyzer that accurately and quickly monitors the chemical composition of elements is essential. The development of recyclable chemicals, as well as hardware equipment, is also needed.
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