To provide a MEMS thermal actuator.
On a microelectronic board 14 a synthetic beam 12 in the form of cantilever is provided extending along the surface of the board, and the base end of the synthetic beam 12 is attached to the board 14 through an anchor part. The anchor part is composed of a first 18 and a second anchor portion 20 with a cavity 36 interposed, and on them 18 and 20, contacting parts 32 and 34 are formed in such a way as mating with them. The synthetic beam 12 has a dual layer structure directed vertically consisting of a first layer 28 and a second layer, wherein the first layer 28 is made of silicon and the second layer 30 made of metal. The demarcated region of the silicon material in the first layer 28 is subjected to doping so that a conducting path having an electric resistance is formed. From the first contacting part 32, current is fed via a route following the electric resistance passage in the first layer 28, the second layer 30, and the second contacting part 34. Thereby the electric resistance passage in the first layer 28 emits heat, and the beam 12 is put in bending displacement parallel with the surface of the board 14 owing to the difference in the coefficient of thermal expansion between the first layer 28 and second layer 30, and a thermal working force is generated.
HILL EDWARD
COWEN ALLEN
