Abstract-We demonstrate single-mode photonic wires in Silicon-on-insulator with propagation loss as low as 2.4 dB/cm, fabricated with deep ultraviolet lithography and dry etching. We have also made compact racetrack and ring resonators functioning as add-drop filters, attaining values larger than 3000 and low add-drop crosstalk.Index Terms-High index contrast, photonic wire, ring resonators, Silicon-on-insulator (SOI) technology.

Abstract-We present a number of compact wavelength-selective elements implemented in silicon-on-insulator (SOI) photonic wires. These include arrayed waveguide gratings (AWGs), MachZehnder lattice filters (MZLFs), and ring resonators. The circuits were fabricated with deep UV lithography. We also address the sensitivity of photonic wires to phase noise by selectively broadening the waveguides, and demonstrate this in a compact AWG with −20 dB crosstalk and an insertion loss of 2.2 dB for the center channels.

For the compact integration of photonic circuits, wavelength-scale structures with a high index contrast are a key requirement. We developed a fabrication process for these nanophotonic structures in Silicon-on-insulator using CMOS processing techniques based on deep UV lithography. We have fabricated both photonic wires and photonic crystal waveguides and show that, with the same fabrication technique, photonic wires have much less propagation loss than photonic crystal waveguides. Measurements show losses of 0.24dB/mm for photonic wires, and 7.5dB/mm for photonic crystal waveguides. To tackle the coupling to fiber, we studied and fabricated vertical fiber couplers with coupling efficiencies of over 21%. In addition, we demonstrate integrated compact spot-size converters with a mode-to-mode coupling efficiency of over 70%.

We demonstrate wavelength-scale photonic nanostructures, including photonic crystals, fabricated in silicon-on-insulator using deep ultraviolet (UV) lithography. We discuss the mass-manufacturing capabilities of deep UV lithography compared to e-beam lithography. This is illustrated with experimental results. Finally, we present some of the issues that arise when trying to use established complementary metal-oxide-semiconductor processes for the fabrication of photonic integrated circuits.

Abstract-High-index-contrast, wavelength-scale structures are key to ultracompact integration of photonic integrated circuits. The fabrication of these nanophotonic structures in silicon-on-insulator using complementary metal-oxide-seminconductor processing techniques, including deep ultraviolet lithography, was studied. It is concluded that this technology is capable of commercially manufacturing nanophotonic integrated circuits. The possibilities of photonic wires and photonic-crystal waveguides for photonic integration are compared. It is shown that, with similar fabrication techniques, photonic wires perform at least an order of magnitude better than photonic-crystal waveguides with respect to propagation losses. Measurements indicate propagation losses as low as 0.24 dB/mm for photonic wires but 7.5 dB/mm for photonic-crystal waveguides.