MEMS RF switch integrated process

The limited temperature photoresist process of making a sealed, transmission line coupled, capacitance coupling change-operated radio frequency MEMS switch comprising the steps of:

• fabricating operationally static metallic elements of said transmission line and said switch on an insulating substrate member;
• disposing a permanent electrical insulating coating over selected of said operationally static metallic elements of said transmission line and switch;
• coating said insulating substrate member and permanent electrical insulating coated operationally static metallic elements with a multiple sub layer comprised photoresist first removable sacrificial layer;
• depositing a shaped thin metal film movable switch element on a top surface of said first removable sacrificial layer;
• covering said shaped thin metal film movable switch element and said photoresist first removable multiple sub layer comprised sacrificial layer with a photoresist second removable sacrificial layer;
• enclosing said photoresist second removable sacrificial layer, said shaped thin metal film movable switch element and said first removable sacrificial layer with a dielectric shell member;
• said enclosing dielectric shell member including a plurality of apertures communicating from within to external of said dielectric shell member;
• extracting said removable sacrificial layers materials from within said dielectric shell member using a dissolving liquid process communicating via said dielectric shell member plurality of apertures;
• and
• overlaying said dielectric shell member with a layer of protecting and said aperture-sealing material of differing material composition from said dielectric shell member.

The limited temperature organic photoresist coating materials based MEMS switch realization method comprising the steps of:

• fabricating metallic elements of said switch in a sequence of photoresist coating, masking, exposing and etching steps ending with MEMS switch elements being held captive on an insulating substrate in a multiple sacrificial layered coating of said photoresist materials;
• enclosing said captive switch elements in a dielectric shell using additional of said photoresist coating, masking, exposing and etching steps compatible with both said fabricating step photoresist coating, masking, exposing and etching steps and with structure formed during said fabricating step photoresist coating, masking, exposing and etching steps;
• said enclosing step including forming in said dielectric shell a plurality of apertures communicating from outside to inside thereof;
• wet releasing said switch elements from captivity within said dielectric shell by said sacrificial layer of said photoresist coating materials by way of reagent received through said plurality of apertures communicating from outside to inside of said dielectric shell;
• and
• covering said plurality of apertures communicating from outside to inside of said dielectric shell with a coating material temperature compatible with said switch elements and with said dielectric shell.