Vacuum Tubes are used in computing, switching, amplification and rectification right up to 60s. Then it died a quick death since most applications solid state device such as semiconductor devices have replaced them. We all know that Semiconductor devices are small in size and cheaper than vacuum tube devices. Silicon transistors are cheaper but they are slower and susceptible to radiation. The performance of Silicon Transistors, far away from Vacuum Tube devices due to their compact size, no heating time, reduced time for electrons to travel. But actually electrons are about 10 times slower in solid material as than in vacuum. Now NASA combined the advantages of Silicon Transistors and Vacuum Tubes, to form ‘Nano Vacuum Tubes‘. They have created it by etching tiny cavities in phosphorus doped silicon NASA combined the advantages of Silicon Transistors and Vacuum Tubes, to form ‘Nano Vacuum Tubes‘. and Source, Drain and Gate are placed around this cavity. The size of the cavity is very small about 150nm, so there is minimum interaction with electrons and air, avoiding the need for true vacuum thereby reducing the manufacturing difficulties and cost. The term ‘Vacuum Tube’ is slightly misleading as true Vacuum is not created in these devices.
As Nano Vacuum Tubes has switching speed up to 0.46 terahertz, it does have immediate potential for consumers to use and this could have great application for terahertz communication.
