An electromechanical actuator 10 is disclosed, having drive elements (14a-d) movable in two dimensions and connected to an actuator backing (12). The actuator backing (12) is made of a material being ferromechanically inactive. Furthermore, the joint between the drive element (14a-d) and the actuator backing (12) is stiff and highly stable. This is achieved by use of an irreversible joint made e.g. by thermoset plastic glues, diffusion bonding or co-sintering. Co-sintering is to prefer. The actuator backing (12) material is selected to be stiff, preferably having a stiffness above 70 GPa and more preferably above 100 GPa, and having a high heat conductivity, preferably above 5 W/mK and more preferably above 10 W/mK, Electrodes (22) are preferably integrated in the actuator backing to increase stiffness as well as improving the heat conductivity. The drive elements (14a-d) are preferably covered (28, 26), at least at the driving surface, by heat-conducting material.