Cavity resonator for reducing phase noise of voltage controlled oscillator

A cavity resonator comprising:

• a semiconductor having a cavity which is defined by four sides, an upper surface and a lower surface;
• a lower metal film located on said four sides and on said lower surface of said cavity in said semiconductor;
• an upper ground plane metal film which covers said upper surface of said cavity in said semiconductor;
• a microstrip line, of predetermined width, which extends from one end of the cavity across to the other end of the cavity to serve as a waveguide, wherein the microstrip line is disposed a uniform predetermined distance from the upper ground plane metal film of the cavity opposite to said lower surface of said cavity;
• and
• two slots, of predetermined dimension, in said upper ground plane metal film, wherein the two slots are parallel to each other and positioned on each side of the microstrip line;
• and
• a matching resistor which is positioned within a gap, of predetermined width, of the microstrip line, wherein the resistor is positioned at the location corresponding to one end of the cavity.