Layered materials, such as bismuth, offer exceptional properties for future integrated circuits (IC). Research is underway to adapt these materials to conventional IC manufacturing processes, like chemical mechanical polishing (CMP). However, CMP of layered materials remains underexplored. This study chose bismuth as a representative to investigate its CMP properties. The results reveal that the material removal rate (MRR) increases rapidly and stabilizes as the H₂O₂ concentration increases. An ultra-high MRR exceeding 10 μm/min is achieved, which is significantly higher than the typical <1 μm/min. A distinctive material removal mode is proposed: shear slipping. This mode differs from the previously reported chemical bonding and mechanical plowing. Specifically, bismuth is oxidized by H₂O₂ to form a Bi₂O₃ surface film, which has a weak interaction with the bismuth substrate, creating a low-shear interface. Under the shearing action of the polishing pad asperities, the surface film slips relative to the substrate, distinct from forming and tearing chemical bonds via chemical bonding and breaking the weakened surface in-plane via mechanical plowing. Consequently, material removal is achieved as micron-sized debris. Furthermore, the shear slipping mode may apply to other layered materials. Adding lubricants and optimizing the polishing pad may help control layered materials removal in CMP.

铋等多层材料为未来的集成电路 （IC） 提供了卓越的性能。目前正在进行研究，以使这些材料适应传统的 IC 制造工艺，如化学机械抛光 （CMP）。然而，层状材料的 CMP 仍未得到充分开发。本研究选择铋作为代表，研究其 CMP 特性。结果表明，材料去除率 （MRR） 迅速增加，并随着 H₂O₂ 浓度的增加而稳定。实现了超过 10 μm/min 的超高 MRR，明显高于典型的 <1 μm/min。提出了一种独特的材料去除模式：剪切滑移。这种模式与之前报道的化学键合和机械犁地不同。具体来说，铋被 H₂O₂ 氧化形成 Bi₂O₃ 表面膜，该膜与铋基材的相互作用较弱，形成低剪切界面。在抛光垫凹凸不平的剪切作用下，表面膜相对于基材滑动，这与通过化学键形成和撕裂化学键以及通过机械犁在平面内破坏弱化表面不同。因此，材料以微米级碎屑的形式实现。此外，剪切滑移模式可能适用于其他多层材料。添加润滑剂和优化抛光垫可能有助于控制 CMP 中分层材料的去除。