Abstract: A method for singulating a group of semiconductor packages containing a plastic molded body. The singulation of the semiconductor packages is effected along a predetermined separation area, wherein, in the predetermined separation area, a metallic layer extending over at least a partial section of the predetermined separation area has to be cut through in addition to a plastic layer formed of a material of the molded body. The method includes the steps of: making a groove into the predetermined separation area of the semiconductor packages by laser engraving, wherein at least a part of the metallic layer extending in the predetermined singulation area is removed, and subsequent separation of the semiconductor packages by mechanical sawing cut along the predetermined separation area.

Abstract: A laser-active optical fiber for a fiber laser or an optical fiber amplifier contains a laser-active fiber core (2) comprising an undoped inner region (22) which is surrounded by an outer region (24) that is doped with a laser-active material. In this manner a high-power laser beam may be generated which has a mode structure, present in the form of a ring mode, which in particular is suitable for laser machining.