Next-generation integrated circuit wiring and in-situ measurement of liquid/metal interface: How much do we understand and how should we use it?

2024 Fiscal Year Final Research Report

• Project/Area Number: 22K04182
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21050:Electric and electronic materials-related
• Research Institution: University of Yamanashi
• Principal Investigator: Kondoh Eiichi 山梨大学, 大学院総合研究部, 教授 (70304871)
• Co-Investigator(Kenkyū-buntansha): 金 蓮花 山梨大学, 大学院総合研究部, 教授 (40384656)
• Project Period (FY): 2022-04-01 – 2025-03-31
• Keywords: 半導体配線材料 / エリプソメトリ / ナノインデンテーション

Outline of Final Research Achievements

This study was carried out with the aim of obtaining basic knowledge for direct bonding of Cu and new wiring materials at room temperature. Mechanical and metallurgical evaluation is essential for room temperature direct bonding. Using a nanoindentation device, we directly bonded metals to each other at room temperature using only pressure bonding, and at the same time developed a new experimental method to evaluate the bonding and interface characteristics of the metals. We also evaluated the formation and desorption process of SAM films and BTA-based protective films for Cu, Co, Mo, and Co-Ti as integrated circuit wiring metals by in-situ ellipsometry observation. Although we were unable to evaluate the layered structures of these metals, we were able to develop a nanoindentation method and make new proposals such as the use of SAM films as protective films before bonding.

Free Research Field

電気電子材料工学

Academic Significance and Societal Importance of the Research Achievements

集積回路の高集積化・微細化に伴い、ウェハを積層しその間を微小な金属配線で接合する三次元的構造デバイスの形成が必要となっている。常温接合ができれば熱負荷やストレス負荷を低減できるが、in-vacuoプロセスは現実的でない。本研究ではウェット処理環境で清浄金属表面を形成・評価する手法と、清浄／非清浄界面を有する金属接合構造の力学的評価を行う手法を構築した。半導体プロセス工学において新しい学術的視点を提供するとともに、金属表面・界面の新しい評価技術を開発できた。