Electrical devices having radiofrequency field effect transistors and the manufacture thereof

A method of manufacturing an electrical device, comprising:

• providing a substrate having a surface;
• and
• forming a radiofrequency field effect transistor on the substrate surface, including:
• forming a carbon nanotube (CNT) layer on the substrate surface, wherein the CNT layer includes electrically conductive aligned carbon nanotubes;
• depositing a pin-down layer on the CNT layer, wherein the pin-down layer covers the CNT layer;
• and
• patterning the pin-down layer to form separate pin-down anchor layers, wherein 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 second portions of the CNT layer are covered by the pin-down anchor layers, and wherein
• for cross-sections in a direction perpendicular to a common alignment direction of the electrically conductive aligned carbon nanotubes in the first portion of the CNT layer:
• the electrically conductive aligned carbon nanotubes have an average linear density in a range from 20 to 120 nanotubes per micron along the cross-sections, and
• at least 40 percent of the electrically conductive aligned carbon nanotubes are discrete from any carbon nanotubes of the CNT layer.