To reduce the dispersion of output characteristics by heating a wafer and a pedestal at a fixed temperature before a trimming process after a pedestal joining process and conducting the annealing process of slow cooling.
A metallized film is formed beforehand onto one surface of a pedestal plate 110 consisting of a plate with a large number of through-holes, and these pedetal plate 110, metallized film and wafer 101 are held by pressure by a pair of electrodes under the state, in which the wafer 101 is placed on the pedestal plate 110. The wafer 101 is held for 192min at 450°C, and heated slowly and second annealing is conducted. A trim resistor formed to the wafer 101 is trimmed by a laser and output characteristics are conformed to reference characteristics, and the wafer 101 is diced completely along half-cut grooves, and separated into each chip. Accordingly, since annealing is performed immediately before a trimming process, the dispersion of the output characteristics of a strain sensor can be reduced.
KARESUE SHIYOUWA (JP)
YOKOYAMA KENICHI (JP)
SUZUKI YASUTOSHI (JP)
