Film bulk acoustic resonator

摘要

FBAR device includes a membrane supporting layer between a substrate and a membrane layer, surrounding an air gap region. The membrane supporting layer support the membrane layer to obtain a robust structure. The substrate has a first area and a second area surrounding the first area. The membrane supporting layer is formed on the second area of the substrate so as to form the air gap on the first area of the substrate. The membrane layer is formed on the membrane supporting layer and the air gap. A first electrode is formed on a portion of the membrane layer. A piezoelectric layer is formed on a portion of the first electrode. A second electrode is formed on a portion of the piezoelectric layer.