Microprocessor having air as a dielectric and encapsulated lines

Abstract

A multi-layer semiconductor circuit comprising a plurality of conductive lines having air as a dielectric between the sides of the conductive lines in a first layer and having a structurally supportive non-metal cap layer at least partially covering the top of the conductive lines in the first layer and separating the air dielectric and conductive lines in the first layer from any subsequent layers. In a multi-layer semiconductor circuit with a plurality of conductive lines, at least the top, the bottom, and the opposite sides of each line are encapsulated by an adhesion-promotion barrier layer, and the barrier layer on the top of each conductive line has an upper surface that is flush with (a) a planar lower surface of a cap layer over the barrier layer, (b) a planar upper surface of a dielectric layer between the conductive lines, or (c) a combination thereof. The dielectric layer between the conductive lines may be air.