PURPOSE: To prevent overetching from occurring and obtain highly reliable printing quality at low cost, by a method wherein an end part of a gap between conductors proximate to a heating resistor provided on the surface of a substrate is shaped in a circular or other similar pattern.
CONSTITUTION: Each of the end parts 5, 5' of gaps between the conductors 4, 4' is formed in a circular or other similar shape. By this, an etching liquid is permitted to flow in the circular parts throughout etching, without stagnating in the parts 5, 5' as in a conventional process, so that the desired pattern can be clearly produced without leaving any residual liquid containing materials of an upper layer or a lower layer. For example, a central part of an Al2O3 substrate is partially glazed, and then an undercoating material Ta2O5, a resistor Cr-Si and conductors Cr and Al are vapor-deposited on the surface of the glazed part by a sputtering method and resistance heating. Further, a photoresist OMR is applied thereto, and exposure to light is conducted by using a photomask, followed by developing.
MIYAKE HIROSHI
FUYAMA MORIAKI
TAMURA KATSU
OGURA SATOSHI
NUNOKAWA ISAO
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