Patent ID: 8769806

Claim:
A method of manufacturing a thermal head, comprising: forming a groove portion in one surface of at least one of a first substrate and a second substrate to be disposed on the first substrate in a stacked state, each of the first substrate and the second substrate having a plate shape; measuring a width dimension of the groove portion formed in the at least one of the first substrate and the second substrate; bonding the first substrate and the second substrate to each other in the stacked state so as to close an opening of the groove portion formed in the at least one of the first substrate and the second substrate; forming a heating resistor on a surface of the second substrate in a region opposed to the groove portion after the first and second substrates are bonded to each other; and forming a protective film for covering and protecting the heating resistor formed on the surface of the second substrate, a thickness dimension of the protective film being set so as to increase with an increase in the measured width dimension of the groove portion and so as to decrease with an increase in a thickness dimension of the second substrate.