Coaxial Waveguide Microstructures Having an Active Device and Methods of Formation Thereof

Abstract

Provided are coaxial waveguide microstructures. The microstructures include a substrate and a coaxial waveguide disposed above the substrate. The coaxial waveguide includes: a center conductor; an outer conductor including one or more walls, spaced apart from and disposed around the center conductor; one or more dielectric support members for supporting the center conductor in contact with the center conductor and enclosed within the outer conductor; and a core volume between the center conductor and the outer conductor, wherein the core volume is under vacuum or in a gas state. Also provided are methods of forming coaxial waveguide microstructures by a sequential build process and hermetic packages which include a coaxial waveguide microstructure.

1 - 20 . (canceled) 
     
     
         21 . A hermetic package including a coaxial waveguide microstructure, comprising:
 a multi-layer coaxial waveguide including a center conductor having one or more layers of a conductive material, an outer conductor comprising one or more walls spaced apart from and disposed around the center conductor, the one or more walls having a plurality of layers of the conductive material, and a non-conductive core volume disposed between the center conductor and the outer conductor; and   a dielectric cap disposed over an endface of the multi-layer coaxial waveguide to hermetically seal the coaxial waveguide at the endface.   
     
     
         22 . The hermetic package according to  claim 21 , wherein the dielectric cap comprises a membrane extending from the center conductor to the outer conductor 
     
     
         23 . The hermetic package according to  claim 22 , wherein the dielectric membrane covers at least an outer periphery of the center conductor and at least an inner periphery of the outer conductor. 
     
     
         24 . The hermetic package according to  claim 21 , comprising a device mounted on the dielectric cap. 
     
     
         25 . The hermetic package according to  claim 21 , wherein the dielectric cap comprises a photopatternable polymer. 
     
     
         26 . The hermetic package according to  claim 21 , wherein the multi-layer coaxial waveguide comprises a dielectric support member disposed between the center conductor and outer conductor at a location to support the center conductor within the outer conductor. 
     
     
         27 . The hermetic package according to  claim 21 , wherein the core volume is a vacuum. 
     
     
         28 . The hermetic package according to  claim 21 , wherein the core volume is a gas. 
     
     
         29 . A method of forming a hermetic coaxial waveguide microstructure by a sequential build process, comprising:
 building up a plurality of layers sequentially on top of one another, the layers comprising one or more of a conductive material, a sacrificial material, and a dielectric material, thereby forming a multi-layer structure, the structure comprising:
 a multi-layer coaxial waveguide including a center conductor having one or more layers of the conductive material, an outer conductor comprising one or more walls spaced apart from and disposed around the center conductor, the one or more walls having a plurality of layers of the conductive material, and a non-conductive core volume disposed between the center conductor and the outer conductor; and 
   providing a dielectric cap disposed over an endface of the multi-layer coaxial waveguide to hermetically seal the coaxial waveguide at the endface.   
     
     
         30 . The method according to  claim 29 , wherein the cap comprises a membrane extending from the center conductor to the outer conductor. 
     
     
         31 . The method according to  claim 30 , wherein the dielectric membrane covers at least an outer periphery of the center conductor and at least an inner periphery of the outer conductor. 
     
     
         32 . The method according to  claim 29 , wherein the step of providing a dielectric cap comprises spin-coating and patterning a photoimageable dielectric over the endface. 
     
     
         33 . The method according to  claim 29 , wherein the sacrificial material is disposed between the center conductor and the outer conductor. 
     
     
         34 . The method according to  claim 33 , comprising the step of removing the sacrificial material so that the core volume comprises a void between the center conductor and outer conductor. 
     
     
         35 . The method according to  claim 34 , wherein the dielectric cap comprises a material that is insoluble in a medium used to remove the sacrificial material. 
     
     
         36 . The method according to  claim 29 , wherein the conductive material is a metal.