Low Temperature and Non-Vacuum Bonding of Wide Bandgap Semiconductor Materials by VUV/Vapor-Assisted Method

2017 Fiscal Year Final Research Report

• Project/Area Number: 26289112
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Electron device/Electronic equipment
• Research Institution: National Institute for Materials Science
• Principal Investigator: Shigetou Akitsu 国立研究開発法人物質・材料研究機構, 構造材料研究拠点, 主幹研究員 (70469758)
• Co-Investigator(Kenkyū-buntansha): 水野 潤 早稲田大学, ナノ理工学研究機構, 上級研究員(研究院教授) (60386737)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 低温大気圧接合 / ワイドバンドギャップ半導体 / VUV

Outline of Final Research Achievements

A novel low temperature hybrid bonding process was developed for GaN, SiC, and Si, including other substrate materials such as PDMS, polyimide, and wiring metals. This process utilized the vacuum ultraviolet (VUV) in nitrogen atmosphere, where the compatible chemical bridging component like water vapor was introduced, therefore the vacuum atmosphere was able to be eliminated. The VUV irradiation in humidified nitrogen generated the radical species of H and OH, then enabled the cleaning of outmost surface, deoxidization of native oxide, and the creation of ultrathin hydrate bridges in single process. Upon heating at 150 C after the touchdown, dehydration condensation in the bridge layers resulted in strong adhesion regardless of the combination of materials. The interfacial structure and property was found robust after the aging test due to sufficient interdiffusion via ultrathin bridge layers. Moreover, a simple LED structure could be fabricated by this VUV/vapor-assisted method.

Free Research Field

表面・界面科学