Improved MEMS piezoelectric vibratory stage with reduced off-axis error

Abstract. Background: The piezoelectric microvibratory stage as a microelectromechanical system (MEMS) actuator can tilt around the X  /  Y axis and translate along the Z axis. However, when the vibratory stage is tilted around the X axis, it also has an undesirable tilting angle around the Y axis. It means that the X axis tilting and the Y axis tilting are not independent; therefore, it is significant to eliminate the coupling of two motions. Aim: The coupling of X  /  Y tilting motion is studied theoretically and decoupled by optimization of structural parameters. Approach: A structural model was established to analyze the reasons of the X  /  Y tilting coupling. Reasonable structure parameters of L-shaped piezoelectric beam were designed to eliminate the off-axis errors caused by X  /  Y tilting coupling. Results: The reason of X  /  Y tilting coupling is that the stiffness of the L-shaped piezoelectric support beam mismatch in the X axis and Y axis directions. The appropriate width ratio of the two segments of the L-shaped piezoelectric beam can reduce the off-axis error effectively. Conclusions: The test results show that the piezoelectric MEMS vibratory stage can achieve X  /  Y tilting motion with the relative off-axis error only at 1%.