We have developed a way to mount ultra-high vacuum windows onto standard ConFlat® vacuum systems with very low stress-induced birefringence. Each window is sealed to a stainless steel flange with a compressed indium wire, and that flange is connected to a vacuum chamber with another indium seal. We find that deformation of a standard ConFlat flange during indium sealing dominates the stress on the window, so an extra-rigid flange is needed for minimal birefringence. With this mounting scheme, the typical residual birefringence is δn = 2.3 10-7 and is unchanged by a 120 C bake.
All Science Journal Classification (ASJC) codes