Low-Loss ($<$ 1 dB) and Polarization-Insensitive Edge Fiber Couplers Fabricated on 200-mm Silicon-on-Insulator Wafers

We present a silicon-on-insulator (SOI) polarization-insensitive fiber-to-fiber coupler fabricated on a 200-mm wafer with the standard complementary metal-oxide-semiconductor technology. The coupling losses from a lensed fiber into a 500-nm-wide SOI waveguide were measured to be less than 1 dB in the 1520- to 1600-nm spectral range and below 3 dB between 1300 and 1600 nm.