Integration of Garnet Films by Using Laser Etching Techniques

A new four-stage technique for integrating multiple iron garnet films on a single substrate is presented. A film is first grown on a GGG substrate by LPE. Ar ion laser etching is used in the second stage to remove a section of this film. Etching terminates automatically at the film-substrate interface. A second film is grown following the contours of the first by hetero-epitaxy in the third stage. The resulting film is flattened in the final stage by laser etching with the substrate and layered film immersed in phosphoric acid. This technique seems promising for realizing a wide variety of highly functional and compact integrated garnet film devices.