Laser sintering of inkjet-printed silver nanoparticles on glass and PET substrates

Laser sintering of inkjet-printed silver nanoparicles was studied. Conducting lines were printed on glass and PET substrates of various thicknesses by a drop-n-demand (DOD) inkjet printer and silver nanoparticle ink. Selective sintering of the printed silver nanopartilces was then performed using laser beam to enhance electrical conductivity. Focused laser beam was irradiated normally to the silver layer printed on the transparent substrates with various beam intensity and various irradiation time. Conductivity and morphology of the laser sintered silver patterns were measured and compared with the results of oven-heated sintering. Temperature elevation by laser irradiation was also calculated based on laser beam intensity, irradiation time, surface reflectivity, and thermophysical property of a substrate to estimate enhancement of the electrical conductivity by laser sintering.