Microelectromechanical switch with fixed metal electrode/dielectric interface with a protective cap layer

A Micro Electro-Mechanical System (MEMS) switch, comprising:

• a substrate;
• an insulator layer disposed over said substrate;
• a bottom electrode formed over said insulator layer;
• a thin protective cap layer disposed over said bottom electrode,
• a dielectric material disposed over said thin protective cap layer;
• a spacer proximate said bottom electrode;
• and
• a pull-down electrode over said spacer and said dielectric material, wherein said thin protective cap layer inhibits the oxidation of said bottom electrode.

A method of manufacturing a Micro Electro-Mechanical System (MEMS) switch, comprising the steps of:

• providing a substrate;
• depositing an insulator layer on said substrate;
• forming a bottom electrode on said insulator layer;
• depositing a thin protective cap layer over said bottom electrode;
• depositing a dielectric material over said bottom electrode and thin protective cap layer;
• and
• forming a pull-down electrode over said dielectric material, wherein said thin protective cap layer prevents the oxidation of said bottom electrode.