AN OVERVIEW OF ION-IMPLANTED OPTICAL WAVE-GUIDE PROFILES

Ion implantation produces a variety of optical changes in insulators including major alterations of the refractive indices. Consequently ion beam implantation has been used to form optical waveguides in a very diverse range of materials. These include key optoelectronic crystals, such as LiNbO3, Quartz, YAG. PLZT or BGO, amorphous glasses such as silica, and organics such as PMMA. Despite the generality of the technique there are major differences in the form of the index profiles. In particular the extraordinary and ordinary indices often behave differently. Electronic excitation and nuclear collision regions of the ion range can differ not only in the form. but also in the sign. of the index change. Further differences are noted in the subsequent thermal stability of these regions. Alternative mechanisms of defect formation, diffusion, stress and preferential surface decomposition are discussed and related to various examples of ion-implanted optical waveguides. The effects of these features are of major importance in the formation of low loss waveguide devices. © 1990.