Membrane transfer method
AssigneeSoitec
InventorsFrançois-Xavier Darras, Bruno Ghyselen
Life of this patent
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Abstract
A method for producing a device comprising a membrane of piezoelectric nature above at least one cavity comprises: a) providing a carrier substrate having a cavity opening out onto its front face, the cavity having a lateral dimension larger than 30 μm; b) providing a donor substrate having a buried weakened plane delimiting a surface layer; c) depositing, on the front face of the donor substrate, a stiffening layer made of piezoelectric material having a thickness greater than 500 nanometers; d) joining the carrier substrate and donor substrate; and e) splitting the donor substrate at the buried weakened plane so as to transfer the membrane comprising the surface layer and the stiffening layer to the carrier substrate.
Claims14
A method for producing a device comprising a membrane of piezoelectric nature above at least one cavity, the method comprising:
- a) providing a carrier substrate having a first face extending over a plane and a cavity opening out onto the first face, the cavity having a lateral dimension in the plane that is larger than 30 μm;
- b) providing a donor substrate having a buried weakened plane formed by implanting light species through a front face of the donor substrate, the weakened plane delimiting a surface layer;
- c) depositing, on the front face of the donor substrate, a stiffening layer made of piezoelectric material having a thickness greater than 500 nm;
- d) joining the carrier substrate and the donor substrate at a bonding interface disposed between the first face of the carrier substrate and the stiffening layer;
- and
- e) splitting, after joining the carrier substrate and the donor substrate, the donor substrate at the buried weakened plane so as to transfer a membrane comprising the surface layer and the stiffening layer to the carrier substrate, the membrane being located above the cavity.
A donor substrate configured to transfer a membrane of piezoelectric nature to a carrier substrate having at least one cavity having a lateral dimension larger than 30 μm, the donor substrate comprising:
- a weakened plane disposed in the donor substrate and delimiting a surface layer;
- and
- a stiffening layer made of piezoelectric material having a thickness greater than 500 nm disposed on the surface layer.
Dependencies are inferred from the claim text.