Nickel-coated free-standing silicon carbide structure for sensing fluoro or halogen species in semiconductor processing systems, and processes of making and using same

A method of manufacturing a gas sensor assembly comprising a free-standing gas sensing element, comprising the steps of:

• depositing on a base structure a first molding material layer;
• depositing a second molding material layer on said first molding material layer;
• patterning said second molding material layer to form recesses therein that defines a predetermined supporting structure;
• depositing a support material in said recesses;
• selectively removing the second molding material layer, to form a support structure;
• depositing on the support structure a gas sensing material;
• and
• selectively removing the first molding material layer to release the support structure, thereby forming a free-standing gas sensing element comprising the released support structure with a layer of gas sensing material coated thereover.

A method of manufacturing a gas sensor assembly, comprising the steps of:

• depositing on a substrate a first molding material layer;
• patterning said first molding material layer to form at least one barrier recess that defines a predetermined barrier structure overlaying the substrate member;
• depositing in said barrier recess a barrier material;
• depositing a second molding material layer over the first molding material layer and the barrier material;
• patterning said second molding material layer to provide contact recesses that define one or more predetermined spaced-apart contacts overlaying the barrier material;
• depositing in said contact recesses a contact-forming material;
• depositing a third molding material layer over the second molding material layer and the contact-forming material;
• patterning said third molding material layer to provide support recesses that define a predetermined support structure overlaying both the contact-forming material and the second molding material layer;
• depositing in said support recesses a support material;
• selectively removing the third molding material to form a protruding support structure;
• depositing a gas sensing material on the protruding support structure;
• and
• selectively removing the first and the second molding materials, thereby forming a free-standing gas sensing element comprising a released support structure coated with the gas sensing material, and a contact/barrier element comprising spaced-apart contacts formed over the barrier layer,
• wherein such free-standing gas sensing element is supported by such spaced-apart upstanding contacts of the contact/barrier element, and wherein the barrier layer of the contact/barrier element overlays and protects the substrate.