Method for manufacturing a film bulk acoustic resonator
A film bulk acoustic resonator, and a method for manufacturing the same. The film bulk acoustic resonator includes a substrate, a protection layer vapor-deposited on the substrate, a membrane vapor-deposited on the protection layer and at a predetermined distance from an upper side of the substrate, and a laminated resonance part vapor-deposited on the membrane. Further, the manufacturing method includes vapor-depositing a membrane on a substrate, forming protection layers on both sides of the membrane, vapor-depositing a laminated resonance part on the membrane, and forming an air gap by removing a part of the substrate disposed between the protection layers. Accordingly, the membrane can be formed in a simple structure and without stress, and the whole manufacturing process is simplified.
1. A method for manufacturing a film bulk acoustic resonator comprising:
vapor-depositing a membrane on a substrate;
forming protection layers on the substrate which abut two sides of the membrane;
vapor-depositing a laminated resonance part on the membrane; and
forming an air gap by removing a part of the substrate disposed between the protection layers.
2. The manufacturing method of claim 1 , wherein the protection layers are formed by a LOCOS process.
3. The manufacturing method of claim 1 , wherein the step of vapor-depositing a laminated resonance part comprises:
vapor-depositing a lower electrode on the membrane;
vapor-depositing a piezoelectric layer on the lower electrode; and
vapor-depositing an upper electrode on the piezoelectric layer.
4. The manufacturing method of claim 1 , wherein the air gap is formed by dry etching.
5. The manufacturing method of claim 1 , wherein the air gap is formed by wet etching.