Manufacturing method for flexible PMUT array

A method of forming a flexible array of piezoelectric micromechanical ultrasonic transducers, comprising:

• providing a carrier configured to support the flexible array of piezoelectric micromechanical ultrasonic transducers (PMUTs);
• providing a release layer configured to adhere the flexible array of PMUTs to the carrier;
• forming the flexible array of PMUTs over the release layer, comprising
• for each PMUT in the flexible array of PMUTs,
• laminating a first polymer layer configured to support the PMUT;
• depositing a sacrificial material configured to pattern a cavity of the PMUT;
• depositing a mechanical layer, wherein the mechanical layer includes a planarization layer configured to provide chemical mechanical planarization to the PMUT, or a mechanical membrane configured to provide stiffness to the PMUT and frequency response adjustment;
• depositing a first electrode configured to be coupled to a circuit ground plane;
• depositing a piezoelectric layer configured to separate the first electrode and a second electrode;
• depositing the second electrode configured to be coupled to a signal;
• and
• creating patterns on the first electrode, the piezoelectric material, and the second electrode configured to route control signals of the PMUT;
• and
• removing the release layer to separate the flexible array of PMUTs from the carrier.