Intel Corporation
STACKED TRANSISTOR STRUCTURES WITH ASYMMETRICAL TERMINAL INTERCONNECTS

Abstract:

Integrated circuitry comprising stacked first and second transistor structures. One of a source, drain or gate terminal of an upper-level transistor structure is coupled to one of a source, drain or gate terminal of a lower-level transistor structure through an asymmetrical interconnect having a lateral width that increases within a dimension parallel to a semiconductor sidewall of the upper-level transistor by a greater amount than in an orthogonal dimension. A dielectric material between the upper and lower transistor structures may be anisotropically etched asymmetrically by orienting a workpiece to be non-orthogonal to a reactive ion flux. Varying an angle between the reactive ion flux and a plane of the second transistor during an etch of the dielectric material may ensure an etched opening is of sufficient bottom dimension to expose a terminal of the lower-level transistor even if not perfectly aligned with the second transistor structure.