Zirconium Nitride Thin-Film Resistors With High Thermal Durability

A ZrN thin-film resistor is proposed as a promising heating resistor for a future thermal printing head used in high-resolution highspeed printing. The ZrN film is prepared by nonreactive sputtering with a hot-pressed ZrN target. The present method is able to control the film characteristics mainly through the nitrogen content in the sputtering atmosphere as well as achieve good reproducible results. Practical films, which have a small resistance change with temperature as well as during aging tests, are provided with resistivities of 0.5 to 5 m .cm. Thermal printing element test pieces with 16-dot/mm resolution are fabricated to examine the thermal durability of the ZrN thin-film resistor when applied to high-speed printing. The results of heat pulse life tests make clear that the elements are applicable to high-speed (a 0.3-ms duration and a 1.0-ms repetition interval) printing of excellent quality and sufficient thermal durability.