Patent ID: 11942919
Assignee: RAYTHEON COMPANY
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 13:
14. A process for making a neutrally stressed released multilayer membrane structure for a bulk acoustic wave resonator comprising:
providing a releasable substrate having a top surface;
forming a first epitaxial layer comprising single-crystal aluminum nitride material on said top surface of said substrate;
forming a second epitaxial layer on said first epitaxial layer opposite said top surface of said substrate, said second epitaxial layer comprising single-crystal scandium aluminum nitride material;
forming a third epitaxial layer formed on said second epitaxial layer opposite said first epitaxial layer, said third layer comprising one of a single-crystal aluminum nitride material or a single-crystal scandium aluminum nitride material; and
removing said substrate from said first epitaxial layer.