Carbon nanotube vacuum transistors

A method for forming a vacuum transistor, the method comprising the steps of:

• covering a substrate with an insulating layer;
• forming at least one back gate in the insulating layer;
• depositing a gate dielectric on the insulating layer over the back gate;
• forming a carbon nanotube layer on the gate dielectric over the back gate;
• patterning the carbon nanotube layer to provide a first portion of the carbon nanotube layer over a first side of the back gate and a second portion of the carbon nanotube layer over a second side of the back gate, wherein the first portion the carbon nanotube layer and the second portion of the carbon nanotube layer are separated from one another by a gap G, and wherein the first portion of the carbon nanotube layer serves as an emitter electrode of the vacuum transistor and the second portion of the carbon nanotube layer serves as a collector electrode of the vacuum transistor;
• forming a vacuum channel in the gate dielectric over the back gate, wherein the vacuum channel is formed in the gate dielectric using an isotropic etching process;
• and
• forming metal contacts to the emitter electrode and to the collector electrode.