Patent Number: 6,297,515

Title: Integrated acoustic thin film resonator

Abstract: An resonator circuit and an integrated circuit including the resonator circuit and method of making. A silicon substrate of a first conductivity type (1) is provided and an integrated circuit TFR circuit (23) is formed on a region of the substrate which includes a stack containing a plurality of alternately non-porous (3,7,11) silicon and porous (5,9,13) silicon layers. A method is provided to deposit layers with alternately opposite conductivity type and convert only one conductivity type but not the other into porous silicon materials. Each of these layers generally has the thickness which is one quarter of an acoutic wavelength of the resonator frequency. A noise isolator (17,19) is disposed along the sidewalls of the stack and extends into the substrate. A region of silicon (29) is disposed on the substrate and separated from the reflector by the noise isolator. At least one of an active and/or passive device (27) is disposed on or in said region of silicon. There can additionally or alternatively be at least one passive device disposed over the noise isolator (25) with an interconnect (21) interconnecting the resonator and the at least one of an active and/or passive device and the at least one passive device. The noise isolator can completely surrounds the stack. The noise isolator is preferably porous silicon.

Inventors: Yuan; Han-Tzong (Dallas, TX)

Assignee: Texas Instruments Incorporated

International Classification: H03H 9/17 (20060101); H03H 9/00 (20060101); H01L 029/78 (); H01L 033/00 ()

Expiration Date: 10/02/2018