POS2-1164
Epoxy vitrimers with high strength and rapid stress relaxation by controlling effectively permanent network crosslink density toward semiconductor packaging
Topic
S2. High-End Characterization/Polymer Physics/Properties
When and Where
Sep 29, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Hae Jung SON
Boseok KANG
Presenter(s)
Hyun Woo Park (Department of Polymer Science & Engineering Dankook University , Jukjeon-ro 152, Suji-gu, Yongin-si, Gyeonggi-do, 16890, Republic of Korea)
Co-Author(s)
Abstract
Advanced memory devices, due to their increasing integration density, demand semiconductor packaging materials that can simultaneously provide excellent thermomechanical stability and efficient stress dissipation to prevent wafer warpage. This study presents an epoxy vitrimer as a potential packaging material, designed to alleviate stress via dynamic bond exchange. A vinylogous urethane-based vitrimer was synthesized from ethyl acetoacetate, tris(2-aminoethyl)amine (TREN), 1,3-bis(aminomethyl)cyclohexane (BAC), and diglycidyl ether of bisphenol A (DGEBA). Ethyl acetoacetate was used as monofunctional dynamic capping agent (MCA) to control permanent crosslink density. The amounts of ethyl acetoacetate and DGEBA were adjusted, following gelation theory, to regulate the permanent network since MCA suppress the reaction of permanent curing agents (TREN, BAC) with the epoxy groups. Therefore, the effect of the extent of permanent cross-linking on the mechanical properties of thermosets, such as stress relaxation and creep, was investigated. Rapid stress relaxation in epoxy vitrimers was achieved by lowering permanent network crosslink density through an increased concentration of dynamic bonds. However, a substantial decrease in permanent crosslink density caused pronounced creep deformation, indicating a trade-off between stress dissipation and dimensional stability. By replacing the bifunctional DGEBA with tetrafunctional TGDDM (4,4’-methylenebis(N,N-diglycidylaniline)), the crosslink density of the vitrimer network was boosted, effectively overcoming this disadvantage. Consequently, the TGDDM-based system, in contrast to the DGEBA-based vitrimer, displayed a higher glass transition temperature, an increased storage modulus, and markedly less creep deformation, while still achieving proficient stress relaxation. The proposed epoxy vitrimer showed a considerable decrease in wafer-level warpage, suggesting its possibility for future semiconductor packaging.
