Optical scanning device and manufacturing method of optical scanning device

A manufacturing method of an optical scanning device that includes a mirror having an optical reflection surface, a movable frame supporting the mirror, a pair of drive beams supporting the movable frame from both sides, drive sources, disposed on the drive beams, causing the movable frame to be swung around a predetermined axis, and a fixed frame supporting the drive beams, the manufacturing method comprising:

• a step of forming a lower electrode on the drive beams;
• a step of forming a piezoelectric thin film on the lower electrode;
• a step of forming an upper electrode on the piezoelectric thin film;
• and
• a step of forming a stress counter film on the upper electrode which generates a compressive stress on the drive beams according to a DC sputtering method, wherein
• the drive beams are, in a state in which the mirror is stationary, supported in a state in which the drive beams are bent with respect to the fixed frame, wherein
• ribs are formed on lower surfaces of the drive beams, and wherein the stress counter film generates the compressive stress and causes the drive beams to be bent in a direction of the lower surface on which the ribs are disposed.