US Patent 10164104 Method to form air-gap spacers and air-gap spacer-containing structures

A device includes an air-gap (i.e., air-gap spacer) formed in situ during the selective, non-conformal deposition of a conductive material. The air-gap is disposed between source/drain contacts and a gate conductor of the device and beneath a portion of the conductive material, and is configured to decrease capacitive coupling between adjacent conductive elements. Prior to deposition of the conductive material, source/drain contact structures are recessed and a selective etch is used to remove sidewall spacers that are disposed between the source/drain contacts and the gate structures.