ALEXANDRIA, Va., June 25 -- United States Patent no. 12,339,587, issued on June 24, was assigned to Carl Zeiss SMT GmbH (Oberkochen, Germany).
"Facet assembly for a facet mirror" was invented by Joachim Hartjes (Aalen, Germany), Alexander Wolf (Essingen, Germany) and Toralf Gruner (Aalen-Hofen, Germany).
According to the abstract* released by the U.S. Patent & Trademark Office: "A facet assembly is a constituent part of a facet mirror for an illumination optical unit for projection lithography. The facet assembly has a facet with a reflection surface for reflecting illumination light. A facet main body of the facet assembly has at least one hollow chamber. A reflection surface chamber wall of the hollow chamber forms at least one portion ...