Fabrication of a microheater based on silver-polyimide metallization with enhanced thermal and mechanical stability

• A flexible silver-PVA microheater was fabricated, achieving a rapid heating response up to 160 °C at 1.50 V, with a stable temperature over extended periods. • Using an innovative combination of surface modification ion exchange (SMIE) and doctor blade deposition, the patterned heating electrode (293–2998 µm wide, 28 µm thick) demonstrated superior adhesion and enhanced stability. • The SMIE method significantly improved adhesion, thermal stability (TGA shows decomposition temperature up to 620 °C), and mechanical reliability (maintaining resistance with <1 % change after 5000 bending cycles). • SEM and EDS analyses revealed a highly uniform distribution of silver particles, reducing porosity at higher voltages, leading to enhanced electrical and thermal conductivity. • The developed microheater presents a cost-effective, scalable, and adaptable solution for disposable and flexible biomedical and electronic applications. The development of flexible, reliable, and cost-effective microheaters is critical for applications requiring precise thermal management. This study presents a novel approach for fabricating flexible silver microheaters using a solution-based polyimide metallization process. By integrating the surface modification ion exchange (SMIE) method with electronic craft cutting, we enhanced electrode adhesion and achieved consistent pattern quality, making the fabrication process more accessible and scalable. The heaters demonstrated excellent thermal properties with a high decomposition temperature of 620 °C and enhanced thermal stability. Thermal characterization using thermogravimetric analysis and differential scanning calorimetry confirmed improved stability, whereas heating performance evaluation showed consistent temperature regulation. The heating performance tests showed rapid temperature increases, achieving approximately 160 °C at 1.50 V and stable temperatures maintained for 60 min under continuous operation. Elemental composition and surface morphology analyses revealed a uniform distribution of silver particles and decreased porosity at higher voltages, enhancing electrical and thermal conductivity. X-ray Diffraction analysis confirmed increased crystallinity at higher voltages, which was correlated with improved material quality. The mechanical durability tests indicated that the heaters could withstand over 5000 bending cycles without significant performance degradation, confirming their robustness for flexible applications. This approach presents a scalable, low-cost alternative to traditional microheater fabrication, opening new opportunities in wearable electronics and point-of-care diagnostics.