Abstract: An integrated circuit includes a base, a first transistor structure on or above the base, and a second transistor structure on or above the base, where the second transistor structure is spaced from the first transistor structure. An insulator material at least partially encapsulates an airgap or other gas pocket laterally between the first transistor structure and the second transistor structure. The gas pocket is at least 5 nm in height and at least 5 nm wide according to an embodiment, and in some cases is as tall or taller than active device layers of the transistor structures it separates.