DEVELOPMENT OF THE NANO-CMP PROCESS APPARATUS CONTROLLED BY OPTICAL RADISTION PRESSURE

本研究的目的是利用化学机械抛光的方法实现平面化，即利用激光束照射产生的光辐射压力在抛光液中产生微粒的聚集标记，并在VLS电路图形上的小投影区域内有目的地进行选择性材料去除。研究了通过激光束照射到硅晶片表面上来产生聚集标记的考虑。提出了一种新的平面化方法，即用激光聚集标记填充凹坑并将其作为一个表面进行抛光，并尝试在FIB加工的沟槽状不平坦表面上获得高的平面度（聚焦离子束）加工硅片表面。该方法具有以下两个独特之处：（1）在硅晶片的表面上通过激光照射形成聚集标记。这些聚集的痕迹是由泥浆中的细颗粒组成的。(2)在硅片表面凹陷区域形成聚集标记并填充后，可以实现硅片的高平坦化，最终采用LAFP（Laser Aggregation Filling-up & Polishing）方法获得了小于1 nm Rq的光滑表面，具有较高的平坦化潜力。

This research aims to realize the planarization with the chemical mechanical polishing where the aggregated marks of fine particles in slurry are created with the optical radiation pressure induced by irradiated laser beam, and to process selective material removal intentionally in small projected areas on the VLS's circuit pattern.In this paper, the considerations to create the aggregated marks by laser beam irradiation onto the surface of silicon wafer were investigated. Furthermore, new planarization method, which fills up the dimples with laser aggregated marks and polish the area as one surface, was proposed and attempted to obtain high planarity on trench-shaped uneven, surface which was processed by FIB (Focused Ion Beam) machining on the silicon wafer surface.This proposed method indicates two unique points as follows ; (1) The aggregated marks are formed with laser irradiation on the surface of silicon wafer. The aggregated marks are made of fine particles in slurry. (2) After aggregated marks are formed and filled up at the recessed areas of surface of silicon wafer, this process is possible to realize high planarity on silicon wafer.As a final result, the smooth surface of less than 1nmRq is obtained with the LAFP (Laser Aggregation Filling-up & Polishing) method, and the method has a high potential for planarization.