Preparation of Fiber-Reinforced Vitrimers and their Laminated Composites for Semiconductor Substrates

Conventional multilayer printed circuit boards (PCBs) frequently suffer from warpage and interfacial delamination due to thermomechanical stress concentrations at the boundaries between core and prepreg layers. To address this, we study a unified substrate approach using a catalyst-free disulfide vitrimer matrix synthesized from diglycidyl ether of bisphenol A (DGEBA) and 4-aminophenyl disulfide (4-AFD), combining thermoset stability with thermoplastic-like bond exchangeability. In this work, the fabrication of glass fiber-reinforced vitrimers (GFRVs) was optimized by tailoring the rheological and viscoelastic properties of the matrix. Precise viscosity control and optimized consolidation pressure minimized the resin thickness, producing void-free composites with a maximized fiber volume fraction. Furthermore, the application of thermal activation triggers dynamic network rearrangements, enabling rapid stress relaxation that effectively suppresses structural warpage. Based on these rheological insights, the multilayer GFRV lamination process was optimized to successfully substitute for conventional multilayer PCB architectures as an integrated system. Compared to conventional manufacturing, this approach eliminates the reliance on chemically unstable B-stage prepregs by utilizing inherently stable, fully cured sheets. It also ensures structural homogeneity via interfacial chemical welding. Ultimately, this approach simplifies the manufacturing workflow while significantly enhancing the long-term reliability and thermal fatigue resistance of high-density electronic packages under harsh operating conditions.