| 摘要 |
PURPOSE:To enhance a printing quality without increasing the power demand, by a method wherein the cross section in a sub-scanning direction of a heating resistor layer forming a thick film thermal head is shaped into a trapezoid with obtuse taper angles theta. CONSTITUTION:On a glazed ceramic substrate 1, a plurality of electrodes 2 are formed using a predetermined mask by photolitho etching etc. After that, a negative-type photosensitive resist 3 is uniformly applied thereon by spin coating etc. In this case, at a predetermined position to be applied with a heating resistor layer, an open part 4 is exposed to light and developed. With an exposure of more than 100-150mJ/cm<2>, as the shape of the side wall of a pattern, the photosensitive resist is provided with the open part 4 having a side wall of reversely tapered cross section with acute angles to the surface of the substrate. Thereafter, a resistor paste is embedded into the formed open part 4 by a doctor blade method and other means, whereby a heating resistor layer 5 is formed and baked at a high temperature. The cross section of the heating resistor layer 5 formed in this manner is shaped into a trapezoid with taper angles of more than 90 deg.C. |
