Common fabrication of multiple FinFETs with different channel heights

A method, comprising:

• providing a starting semiconductor structure, the starting semiconductor structure comprising a substrate and at least two fins on the substrate and surrounded on front and back sides thereof by a first isolation material;
• recessing at least a portion of one or more and less than all of the at least two fins, resulting in at least one fin recess;
• wherein the recessing comprises:
• creating dummy gate stacks and spacers over channel regions of the at least two fins, each of the dummy gate stacks comprising a bottom dielectric layer, a middle layer of dummy gate material, and a top gate cap;
• creating sources and drains in source and drain regions, respectively, of the at least two fins;
• removing the dummy gate stacks and top portions of the spacers, the removing exposing a top planar surface of each of the channel regions while avoiding exposing surfaces of the channel regions other than the top planar surface of each of the channel regions;
• and
• recessing the top planar surface of each of the channel regions of the one or more and less than all of the at least two fins while avoiding recessing the sources and drains.