Deep x-ray lithography fabrication of mm Wave cavities at the Advanced Photon Source.

Millimeter-wave (mmWave) accelerating cavity structures have been manufactured using the deep x-ray lithography (DXRL) technique. These cavity structures have potential applications as parts of linear accelerators, microwave undulatory, and mm-wave amplifiers. The microfabrication process includes manufacturing of precision x-ray masks, exposure of positive resist by x-rays through the mask, resist development, and electroforming of the final microstructure. Prototypes of a 32-cell, 108-GHz constant-impedance cavity and a 66-cell, 94-GHz constant-gradient cavity were fabricated at APS. Using an HP8510C 26-GHz vector network analyzer, rf measurements are being prepared with a frequency up- and down-converter before and after a test cavity structure. Preliminary design parameters for a 91-GHz multi-module klystron along with an overview of the DXRL technology are also discussed