A method of making a microelectromechanical microwave vacuum tube device is disclosed. The device is formed by defining structural regions and sacrificial regions in a substrate. The structural regions have flexural members. The substrate is treated to remove the sacrificial regions and release the structural regions such that the structural regions are moveable by the flexural members. The structural regions include a device cathode, a device grid or both a device cathode and a device grid. The cathode comprises electron emitters. The device further includes an output structure where amplified microwave power is removed from the device. In the method, the cathode surface and the grid surface are moved to a position where they are substantially parallel to each other and substantially perpendicular to the substrate. The device further comprises an anode that is substantially parallel to the cathode surface and the grid surface.