ELECTRIC FIELD GAP DEVICE AND MANUFACTURING METHOD

摘要

Substrate material is oxidised around side walls of a set of channels. A shielding structure means there is more oxide growth at the top than the bottom with the result that the non-oxidised substrate material area between the channels forms a tapered shape with a pointed tip at the top. These pointed substrate areas are then used to form cathodes.

主权项

1. A method of forming an electric field gap structure, comprising:
providing a silicon substrate; etching cathode channels into the substrate; lining the resulting surface with a lining dielectric layer; forming shielding regions on the cathode channel side walls but leaving an unshielded portion at the top of the cathode channels; oxidising the substrate at the unshielded portion of the cathode channels, thereby to leave pointed non-oxidised substrate regions between the cathode channels; etching away the layers at and above the pointed substrate regions providing a cathode contact over each pointed substrate region; forming a sacrificial layer over the cathode contacts; providing an anode metal layer over the sacrificial layer; etching the sacrificial layer to form a cavity between the cathode contacts and the anode metal layer.