| 摘要 |
<p>PURPOSE:To obtain a long life and low cost thermal head having large specific resistance, low in a temp. coefficient of resistance and having pulse resistance, by using a Ta-SnO2-SiO2 membrane as a heat generating resistor. CONSTITUTION:An insulating substrate 1 composed of alumina, a heat accumulating glazed glass layer 2, a heat generating resistor layer 3, electrodes 4, 5 composed of Cr, Cu or Au and a protective film composed of SiO2, Ta2O5 or SiC are successively formed from below. Then, Ta-SiO2 and Ta-SnO2-SiO2 are used in the heat generating resistor 3. A specific resistance value is changed according to a sputtering condition but control is performed by the wt. mol.% of Ta, SiO2 and SnO2 and, with respect to Ta-SiO2, sputtering is performed under such a condition that Ta is set to 60-50%, the remainder SiO2 to 40%, SnO2 to 1-5% and the remainder to Ta on the basis of the wt. mol.% of a target. In the case of Ta-SiO2, a temp. coefficient of resistance is largely changed along with a rise in specific resistance but, when SnO2 is added, the temp. coefficient of resistance is low and reduced in change.</p> |
