Characteristics of piezoelectric actuator on Si membrane were investigated. Si membranes were fabricated as a function of size using bulk micromachining method. Bottom electrode Ag-Pd and piezoelectric thick films were fabricated using screen printing method, respectively. Piezoelectric thick films were sintered by rapid thermal annealing (RTA). Top electrodes Pt were deposited by DC sputtering system. We analyzed micro structure by scanning electron microscope (SEM) and investigated dynamic properties by MTI2000. Therefore, piezoelectric thick film on Si membrane had P-r of 15.7 muC cm(-2). The maximum displacement of micro actuator had 0.05 mum. We find the combination of thick film printing and MEMS process to form a Si membrane micro actuator. (C) 2004 Elsevier B.V All rights reserved.