Thermally Stable Thin Polymeric Multi-Layer Fromation with ALD

2014 Fiscal Year Final Research Report

• Project/Area Number: 25630118
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Electronic materials/Electric materials
• Research Institution: Tohoku University
• Principal Investigator: FUKUSHIMA Takafumi 東北大学, 未来科学技術共同研究センター, 准教授 (10374969)
• Co-Investigator(Kenkyū-buntansha): MARIAPPAN Murugesan 東北大学, 未来科学技術共同研究センター, 産学官連携研究員 (10509699) ; BEA Jichel 東北大学, 未来科学技術共同研究センター, 助教 (40509874)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 気相堆積重合 / ポリイミド / TSV

Outline of Final Research Achievements

A novel approach to suppress the conventional Cu-TSV induced thermo-mechanical stress in 3D-LSI chip is proposed, fabricated and tested. In this approach, a thermal-chemical-vapor-deposition grown organic polyimide is conformably deposited along the side wall of the TSV. Compared to ALD, the thickness controllability is not so high, but relatively high thickness control with a resolution of 10 nm in thickness is realized. The deposition rate is approximately 100-200nm/min. The step-coverage is approximately 80% for high-aspect-ratio TSV with the depth of 50 um and the diameter of 5 um, and the resulting polyimide thin layer is very pure and shows high thermal stability. As-grown polymer was evaluated for their role in minimizing the thermo-mechanical stress in vicinal and via-space Si. It was found that replacing the conventional SiO2 dielectric liner with organic polymer greatly helps in suppressing the thermo-mechanical stress.

Free Research Field

高分子化学