To eliminate separation and distortion and facilitate high-resolution printing by using as a plate-like body ceramics, glass or glass ceramics of a specific coefficient of thermal expansion at a specific temperature.

An ink-jet head shown in Fig. 1(a) comprises a silicon member 9 having a plurality of recessed parts constituting ink chambers 1 and a nozzle plate 8 as a plate-like body layered to cover the ink chambers 1. A nozzle 2 is formed in the nozzle plate 8, and a part of the silicon member 9 is made a diaphragm part 9a. A piezoelectric element 5 having electrodes 7, 6 is united on the diaphragm part 9a. The nozzle plate 8 layered to the silicon member 9 is formed of ceramics, glass or glass ceramics having a coefficient of thermal expansion of 1.0-5.0×106/°C at 40-200°C. When the nozzle plate is united to the silicon member 9 by thermocompression bonding or the like, separation or the like danger can be prevented because of a small difference of coefficients of thermal expansion to the silicon member 9 (2-4×106/°C).