Preparation of ultra-hard and low-friction carbon nitride film from high-density plasma with coexist of ions and radicals

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14440
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 26050:Material processing and microstructure control-related
• Research Institution: University of Hyogo
• Principal Investigator: Tanaka Ippei 兵庫県立大学, 工学研究科, 助教 (40781034)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: プラズマ / CVD / 窒化炭素 / 高硬度 / アモルファス

Outline of Final Research Achievements

This study aimed to synthesize an ultra-hard and ultra-low friction nitrogen-carbon film that achieves a long lifespan and low loss on sliding surfaces. A high-density reaction field that simultaneously generates CN radicals and ions was formed, preparing carbon nitride films with high nitrogen content and high C-N bonding. Using the Microwave sheath-Voltage combination Plasma (MVP) method for carbon nitride synthesis, the feed gas, microwave frequency, and duty ratio were controlled to regulate the emission intensity ratio of N2+ and CN radicals in the plasma. By increasing the emission intensity ratio of CN radicals and using C7H8 as a carbon source, it was possible to increase the nitrogen content and the ratio of C-N single bonds in the film.

Free Research Field

薄膜工学

Academic Significance and Societal Importance of the Research Achievements

窒化炭素はダイヤモンドよりも硬い可能性がある材料であるが、これまでに超硬質な窒化炭素は得られていない。本研究では高密度プラズマを用いることでN2+やCNラジカルの共存する反応場を形成できることを明らかにした。そのプラズマから得られた窒化炭素の窒素量や結合状態は原料ガスに大きく影響することを学術的に示した。この知見は超硬質窒化炭素の生成に貢献し、窒化炭素合成技術の発展に寄与するものである。