A vacuum transistor includes a substrate and a first terminal formed on the substrate. A piezoelectric element has a second terminal formed on the piezoelectric element, wherein the piezoelectric element is provided over the first terminal to provide a gap between the first terminal and the second terminal. The gap is adjusted in accordance with an electrical field on the piezoelectric element.

A vacuum transistor includes a substrate and a first terminal formed on the substrate. A piezoelectric element has a second terminal formed on the piezoelectric element, wherein the piezoelectric element is provided over the first terminal to provide a gap between the first terminal and the second terminal. The gap is adjusted in accordance with an electrical field on the piezoelectric element.

An ion generator including a vacuum chamber; an anode in the chamber, and two movable cathodes in the chamber whereby the distance of the cathodes relative to the anode can be varied. A servo actuated motor can be operably connected to each movable cathode to move the cathodes in the chamber and modify the plasma generated.

A vacuum transistor includes a substrate and a first terminal formed on the substrate. A piezoelectric element has a second terminal formed on the piezoelectric element, wherein the piezoelectric element is provided over the first terminal to provide a gap between the first terminal and the second terminal. The gap is adjusted in accordance with an electrical field on the piezoelectric element.

A vacuum transistor includes a substrate and a first terminal formed on the substrate. A piezoelectric element has a second terminal formed on the piezoelectric element, wherein the piezoelectric element is provided over the first terminal to provide a gap between the first terminal and the second terminal. The gap is adjusted in accordance with an electrical field on the piezoelectric element.

A vacuum transistor includes a substrate and a first terminal formed on the substrate. A piezoelectric element has a second terminal formed on the piezoelectric element, wherein the piezoelectric element is provided over the first terminal to provide a gap between the first terminal and the second terminal. The gap is adjusted in accordance with an electrical field on the piezoelectric element.

A vacuum transistor includes a substrate and a first terminal formed on the substrate. A piezoelectric element has a second terminal formed on the piezoelectric element, wherein the piezoelectric element is provided over the first terminal to provide a gap between the first terminal and the second terminal. The gap is adjusted in accordance with an electrical field on the piezoelectric element.