Few IC (Integrated Circuit) engineers were cognizant of that defect scanning with low power laser by COMPASS (Name of one typical tool for defect scanning) will impact the chips, and defect scanning was widely used in IC manufacturing. This paper describes a real low yield case, which found the capacitors of DRAM was damaged by laser scanning when output power is 378 mW, and the rootcause was that the silicon of capacitor's surface was melted by the laser, however the silicon's melting point is 1420 ℃ ,. This paper points out the safe output power for COMPASS laser scanning is ≤ 100mW, and the study will help engineers and machine makers to realize the possible damage of laser to submicron process like IC manufacturing, and the paper also provides some damage database for the future development for laser rapid thermal processing.%在集成电路芯片制造中,激光被广泛应用于缺陷扫描或者相关的光学量测工具中.未见报道低功率的缺陷扫描时,输出功率仅数百毫瓦且扫描速度很快时,会对熔点达1 420℃上的硅芯片造成影响,在制造中以Compass为代表的缺陷扫描工具被广泛而无顾虑地应用在芯片制造中.然而通过在动态储存器制造中的一个低良率事件,介绍了缺陷扫描及动态储存器的基本原理,并指出在378 mW输出功率时,缺陷扫描能将电容表面硅重熔,导致电容结构被破坏.通过试验、计算指出输出功率≤100 mW是安全使用功率,为芯片制造业界提供了关于表面材料为硅、氧化硅、氮化硅使用指南,避免了因Compass为代表的缺陷扫描工具广泛应用带来的额外损伤,并为以后的芯片激光快速热处理研究提供了损伤研究依据.
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