The all-aluminum alloy vacuum system was applied for TRISTAN vacuum system, molecular beam epitaxy and chemical vapor deposition processes, and other general purpose ultrahigh vacuum systems. The extremely high vacuum (XHV) of the order of 10-13 Torr has been obtained. One of the basic technologies of the aluminum alloy ultrahigh vacuum system is the surface control of the aluminum alloys with regard oxide layers. Extrusion, machining, and heating in oxygen and argon atmosphere provide a thin, stable and high density oxide layers on the aluminum alloys, and extremely low outgassing rate after 150°C baking procedure was achieved. The oxide layer was characterized by SEM, AES, IMA, and TENT. A high purity aluminum with low internal gas content has superior performance for the thermal desorption, adsorption, and dynamic desorption. A clad material of the high purity aluminum and high strength aluminum alloys are described.
