Patent ID: 8189021

Claim:
A thermal head manufacturing method, comprising: a concave portion forming step of forming a concave portion on one surface of a supporting substrate; a bonding step of bonding an upper substrate, which is made of glass shaped like a substantially flat board, to the one surface of the supporting substrate where the concave portion has been formed in the concave portion forming step, in a manner that hermetically seals the concave portion and forms a hollow portion; a heating step of heating the supporting substrate and the upper substrate which have been bonded together in the bonding step, to thereby soften the upper substrate and expand gas trapped inside the hollow portion to cause the upper substrate to be deformed by plastic deformation so as to rise up toward an opposite side from the hollow portion; a leveling step of leveling a surface of the upper substrate which has been deformed by plastic deformation in the heating step that is opposite from the hollow portion; and a heating resistor forming step of forming a heating resistor on the upper substrate so as to be opposed to the hollow portion, wherein the heating step concavely curves a surface of the upper substrate that is on the hollow portion side.