Electrical devices having radiofrequency field effect transistors and the manufacture thereof

Electrical device including a substrate having a surface and a radiofrequency field effect transistor (RF-FET) on the substrate surface. RF-FET includes a CNT layer on the substrate surface, the CNT layer including electrically conductive aligned carbon nanotubes, and pin-down anchor layers on the CNT layer. A first portion of the CNT layer, located in-between the pin-down anchor layers, is not covered by the pin-down anchor layers and is a channel region of the radiofrequency field effect transistor and second portions of the CNT layer are covered by the pin-down anchor layers. For cross-sections in a direction perpendicular to a common alignment direction of the aligned CNTs in the first portion of the CNT layer: the aligned CNTs have an average linear density in a range from 20 to 120 nanotubes per micron along the cross-section, and at least 40 percent of the aligned CNTs are discrete from any CNTs of the CNT layer.