A heater including a plate-shaped substrate having a heating surface for heating an object and a heater element provided in the substrate or on its surface. The inverter includes switching elements. The safety mechanism is configured to actuate upon receipt of a signal from the sensing mechanism. the two platform halves include the openings with side walls that are curved to follow the contour of the airfoil root so that the airfoil is secured within the platform halves against all directions of movement. A vertical opening is formed in the second dielectric layer that extends down to the contact hole, and a pillar-shaped second polysilicon layer is formed in the opening, that the bottom end of the second polysilicon layer is electrically connected to the first polysilicon layer in the contact hole.