The Production of Thin Be Foils

A procedure for making Be foils between 10{sup -5} cm. and 10{sup -3} cm. thick, and with diameters up to an inch and a half is described, and methods of mounting these foils are indicated.The problem of making thin Be foils was presented in connection with focusing the proton beam in the Berkeley Linear Accelerator, and although the foils are not now used in the accelerator, they have proved to be quite useful as thin targets, target supports, thin windows, etc. The Be was evaporated in vacuum and deposited on a metal collector plate. The problems encountered were: (1) obtaining reproducible quantities of evaporated Be; (2) stripping of Be from the collector plates; (3) preventing curl of the foils when they were stripped; and (4) mounting the foils