Nano-materials for adhesive-free adsorbers for bakable extreme high vacuum cryopump surfaces

摘要

A cryosorber panel having nanomaterials used for the cryosorption material, with nanomaterial either grown directly on the cryopanel or freestanding nanomaterials attached to the cryopanel mechanically without the use of adhesives. Such nanomaterial cryosorber materials can be used in place of conventional charcoals that are attached to cryosorber panels with special low outgassing, low temperature capable adhesives. Carbon nanotubes and other nanomaterials could serve the same purpose as conventional charcoal cryosorbers, providing a large surface area for cryosorption without the need for adhesive since the nanomaterials can be grown directly on a metallic substrate or mechanically attached. The nanomaterials would be capable of being fully baked by heating above 100° C., thereby eliminating water vapor from the system, eliminating adhesives from the system, and allowing a full bake of the system to reduce hydrogen outgassing, with the goal of obtaining extreme high vacuum where the pump can produce pressures below 1×10−12 Torr.

主权项

1. A method of pumping a vacuum system to an extreme high vacuum (XHV), comprising:
a) providing a closed cycle helium refrigeration cryopump with a removable coldhead and a cryosorption panel therein; b) securing an adhesive-free nano-material to said cryosorption panel to form a cryosorption surface within said cryopump; c) fully baking the cryosorption panel at a temperature greater than 100° C. to reduce the hydrogen outgassing load and eliminate water vapor from the cryopump; and d) operating the cryopump until a pressure below 10−12 Torr is achieved in the vacuum system.