Abstract: A thin film solar cell includes a protection layer, a substrate and a photovoltaic conversion structure having a stack of one or several of non-planar light absorption layers, a first conductive layer being light transmissive and a second conductive layer being at least partially transparent or totally reflective. When the second conductive layer is totally reflective, it reflects the sunlight to the adjacent part of the thin film solar cell, proceeding another photovoltaic conversion and generating electric power again. If the non-planar light absorption layer is sloped enough, there will be several photovoltaic conversions produced by the same incident sunlight. More power will be generated and the efficiency of conversion is increased. If the second conductive layer is at least partially transparent, the incident light will be reflected less. However, the structure will provide several opportunities of photovoltaic conversions for the light with larger incident angle.

Abstract: This is a fabrication process for Y-branch nickel/zinc-indiffused polarization splitters on lithium niobate. The fabrication technology needs only two nickel/zinc indiffusions; one at a high temperature and the other at a lower temperature. Nickel/zinc-indiffused waveguides can support single-ordinary, single-extraordinary, and random polarization waves depending on the fabrication process parameters. High extinction ratios can be achieved due to the inherent single-polarization of the waveguides. The splitting ratios of the TE and TM modes are sufficiently high for practical applications.