Detection of potential defects on small-scale interfacial structures

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K03864
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18010:Mechanics of materials and materials-related
• Research Institution: Kindai University (2020-2021); 北九州市環境エレクトロニクス研究所 (2018-2019)
• Principal Investigator: shishido nobuyuki 近畿大学, 理工学部, 講師 (00570235)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 界面強度 / エレクトロニクス / 欠陥 / 材料組織

Outline of Final Research Achievements

Copper interconnect systems of semiconductor devices has a risk of mechanical fracture along with the trend of further integration and miniaturization, because of many weak interfaces stacked to compose multilayered copper/dielectric systems. In order to estimate the fracture risk of the semiconductor products, not only the values of those adhesion strengths but also the information of the existing defect that can possibly initiate the interfacial fracture are essential. In this research, both the adhesion strength and the stochastic distribution of defect size at copper/dielectric interface that can be regarded as an equivalent crack were estimated. The crack extension behavior during the thermal load test as the same as a semiconductor process, shows good agreement with the developed model based on the fracture strength dependent on the microstructure of metal interconnect.

Free Research Field

破壊力学

Academic Significance and Societal Importance of the Research Achievements

現時点で配線強度の脆弱箇所にサブミクロンスケールで直接アクセスできる可能性をもった唯一の方法論を用いて、実際に材料微視構造スケールの脆弱部の定量的強度情報を、試験的ではあるが抽出することができた。本方法論を発展させることで、半導体デバイスなどの破壊リスクを定量化する設計手法に結びつけることが期待できる。また、材料科学的観点からマイクロ・ナノ構造体の変形挙動は徐々に明らかにされているが、機械工学の観点からの重要性が高い異材界面の付着強度といった、より複雑な系について理論体系を整備するための一助となることが期待できる。