Micro-electro-mechanical variable capacitor for radio frequency applications with reduced influence of a surface roughness

A mobile phone, comprising:

• a receiving circuit that receives an RF signal;
• and
• a micro-electro-mechanical variable capacitor that includes:
• a first electrode and a second electrode, configured to be spaced apart at a distance varying according to an external actuation, and a dielectric region arranged on said first electrode;
• further including an intermediate electrode arranged on said dielectric region.

A process for manufacturing a micro-electro-mechanical variable capacitor, comprising:

• forming a first electrode on a supporting layer;
• forming a second electrode, suspended over said first electrode and free to move with respect to said first electrode;
• and
• forming a dielectric region on said first electrode,
• further including forming an intermediate electrode on said dielectric region.

A process for manufacturing a micro-electro-mechanical capacitive switch on a RF transmission line having a signal line and a ground line, comprising:

• forming a dielectric region on said signal line;
• and
• forming a movable electrode electrically connected to said ground line and suspended over said signal line and free to move with respect to said signal line,
• further including forming an intermediate electrode on said dielectric region.