When D decreased, the accumulation of heat became faster and the curing depth became deeper, the carbon inside the films may be removed because of the increasing temperature.
It was curing depth and curing degree at different depth of the films that made the electrical resistivity of the silver films different.
It meant that the curing depth increased as the decrease of D. When curing depth was too small to eliminate all organic solvents in inkjet-printed silver film, only the organic substances nearing to the surface were removed that had little effect on the surface morphology.
We believed that the curing depth was affected by D while the curing degree was affected by both UV curing time and D according to the results from Fig. 5 and Fig. 6a.
Moreover, the curing depth will be deeper and the removal of the organic substances will be promoted when D decreases, which means radiation becomes stronger.
While D decreased, the silver films were exposed to higher levels of UV radiation, which meant the curing depth became deeper, the UV curing and the generation of heat became faster.
