Development of heating resistor for versatile thermal print heads

Improvement in shock and heat resistance of meander-shaped tantalum nitride heating resistors used in facsimiles and other apparatuses is studied, and life prolongation is achieved under the condition of a large drive power. To solve the problem of resistor failure under high-power and high-speed conditions, the causes of heating resistor deterioration are studied. After predicting the temperature distribution at curves of the meander and confirming the effect of some measures, a simulation for thickness-wise temperature distributions is conducted that shows that the temperature rises and falls violently only in the vicinity of the heating resistor. As a means for improvement, the meander-shaped heating resistor is placed between SiO₂ layers. With this structure, the resistance to heat and to thermal shock is improved remarkably. Using the results of the analysis and experiments, a heating resistor is obtained with a remarkably improved resistance to thermal shock