Use of ceramic materials for light weight x-ray optics

Nowadays the most used technology to obtain thin and light mirror shells for x-ray optics is the replica technique by nickel electroforming. This technology has been successfully employed for projects like SAX, JET-X and XMM. Nevertheless, the high density of the nickel poses some limitations to the possibility of extending the use of this technology for the future x-ray missions demanding high collecting area, good angular resolution acid low weight of the optics. In the paper we analyse which are the present limits of the nickel electroforming technology and we underline the potentiality of using SIC and other ceramic materials for the manufacture of large and light x-ray optics. Possible manufacturing process are proposed and preliminary results of prototypes of ceramic mirror shells are presented.