Ученые визуализировали химические изменения на границе меди и изоляции в полупроводниках

Toray Research Center visualizes Cu/low-k interface changes with AFM-IR KEY POINTS - Toray Research Center and Shibaura Institute directly visualize Cu/low-k interface changes with AFM-IR - Researchers find lower Si-CH3 and Si-H bonds and higher hydroxyl-related components near copper wiring - Journal of Applied Physics paper points to a nanoscale tool for analyzing process-induced semiconductor interface damage Toray Research Center and Shibaura Institute of Technology's College of Design Engineering, working with Professor Masao Tanabe, said on Aug. 28 they had directly visualized nanoscale chemical structure changes near the interface between copper wiring and low-k insulating films used in semiconductor interconnects, using atomic force microscope infrared spectroscopy, or AFM-IR. The result addresses a long-standing measurement problem in semiconductor wiring structures, where conventional infrared spectroscopy averages signals over areas of several micrometers or more and makes it difficult to isolate chemical changes occurring only in the immediate vicinity of copper lines. AFM-IR combines infrared spectroscopy with atomic force microscopy and can analyze localized regions on the scale of several tens of nanometers. Using a Cu/low-k insulating film sample designed to simulate a semiconductor wiring structure, the researchers found that Si-CH3 and Si-H bonds decreased near the copper wiring compared with the central part of the low-k film, while components derived from hydroxyl groups increased. The chemical changes were concentrated in an extremely narrow region extending several tens of nanometers from the interface. Those changes matter because Si-CH3 groups help maintain the low dielectric constant of the insulating film. The observed reduction in Si-CH3 and Si-H bonds, together with the increase in hydroxyl-related components, could lead to deterioration in dielectric properties and help explain one cause of semiconductor device performance degradation. The findings were published in the Journal of Applied Physics, with online publication on Aug. 5, 2026. The release described the journal as a peer-reviewed international publication of the American Institute of Physics covering semiconductors, devices, electronic materials and nanostructured materials. As chip performance for artificial intelligence and data center applications increases, circuit miniaturization has advanced, making signal delay and leakage current more significant as wiring widths and spacing shrink. Low-k insulating materials are used with copper interconnects to reduce unwanted electrical interference between lines and support faster operation and lower power consumption. Small chemical structure changes are known to arise near the Cu/low-k interface during manufacturing steps such as etching, cleaning and chemical mechanical polishing, or CMP. Toray Research Center said the AFM-IR technique can help analyze the location and nature of such interface damage and material degradation at the nanoscale, supporting semiconductor materials development, process improvement, and higher-performance, higher-reliability chip design. © Copyright 2026 IBTimes JP. All rights reserved.