Method of manufacturing film bulk acoustic resonator using internal stress of metallic film and resonator manufactured thereby
A method of manufacturing a film bulk acoustic resonator and the resonator manufactured thereby. The method includes the laminating a sacrificial layer on a semiconductor substrate, removing a predetermined area from the sacrificial layer to realize electric contact between a signal line of the semiconductor substrate and a lower electrode, forming the lower electrode by depositing metal film for lower electrode on the sacrificial layer, by patterning based on a shape of the sacrificial layer, forming a piezoelectric layer by depositing a piezoelectric material on the lower electrode and by patterning based on a shape of the lower electrode, and forming an upper electrode by depositing metal film on the piezoelectric layer and by patterning based on a shape of the piezoelectric layer, wherein at least one of a deposition pressure and a deposition power is controlled to generate upward stress when depositing the metal film for the lower electrode.
1. A method of manufacturing a film bulk acoustic resonator, comprising:
laminating a first layer on an upper surface of a semiconductor substrate;
removing a predetermined area from the first layer for electric contact between a signal line of the semiconductor substrate and a lower electrode layer;
forming the lower electrode layer by depositing a first metal film on an upper surface of the first layer, wherein the predetermined area has been removed, and by patterning the first metal film based on a shape of the first layer;
forming a piezoelectric layer by depositing a piezoelectric material on an upper surface of the lower electrode layer and by patterning the piezoelectric material based on a shape of the lower electrode layer; and
forming an upper electrode layer by depositing a second metal film on an upper surface of the piezoelectric layer and by patterning the second metal film based on a shape of the piezoelectric layer, wherein at least one of a deposition pressure and a deposition power is controlled to generate a predetermined amount of upward stress when depositing the first metal film for the lower electrode.
2. The method of claim 1 , further comprising forming wrinkles of a predetermined shape by patterning a first area between the predetermined area removed from the first layer and a second area, on which the piezoelectric layer is to be laminated.
3. The method of claim 2 , wherein a cross section of the wrinkles of the predetermined shape is either of a sawtooth shape or of a consecutive half-circular shape.
4. The method of claim 1 , further comprising forming first bend prevention grooves by patterning the lower electrode layer to form a predetermined second bend prevention grooves on a portion of the upper electrode layer corresponding to the piezoelectric layer.
5. The method of claim 1 , wherein the first layer is a sacrificial layer.