Patent ID: 8559273

Claim:
A method for fabricating a high frequency imagery transducer for an imagery device, said imagery transducer including one or more composite crystal elements, comprising the steps of: providing an oriented single crystal plate of a piezoelectric material having a thickness electromechanical coupling factor k t in the range of approximately 0.65-0.90; etching said oriented single crystal plate with photolithography based micromachining to form a plurality of hybrid piezoelectric structures separated by a plurality of kerfs; wherein said photolithography based micromachining further includes the steps of: (a) forming a hard metal mask over portions of said plate where said plurality of hybrid piezoelectric structures are to be formed separated by said plurality of kerfs; (b) said kerfs including at least one kerf direction having a range of approximately 30 to 35° degrees from a noted orientation direction for said single crystal plate operative to minimize a clamping effect according to the following formula: d′ 31 =d 31 *Cos(θ)*Cos(θ)+d 32 *Sin(θ)*Sin(θ); (c) conducting at least one of a step of reactive-ion etching (RIE) and deep reactive ion etching (DRIE); (i) said hybrid piezoelectric structures having a vertical etching profile of at least 85°; filling said kerfs with a polymeric material to form a unitary assembly; conducting a fine mechanical finishing step of said unitary assembly; coating electrodes on said unitary assembly; and assembling said unitary assembly with a backing operative to form said imagery transducer for said imagery device.