14,635 research outputs found
High-Q-factor Al [subscript 2]O[subscript 3] micro-trench cavities integrated with silicon nitride waveguides on silicon
We report on the design and performance of high-Q integrated optical micro-trench cavities on silicon. The microcavities are co-integrated with silicon nitride bus waveguides and fabricated using wafer-scale silicon-photonics-compatible processing steps. The amorphous aluminum oxide resonator material is deposited via sputtering in a single straightforward post-processing step. We examine the theoretical and experimental optical properties of the aluminum oxide micro-trench cavities for different bend radii, film thicknesses and near-infrared wavelengths and demonstrate experimental Q factors of > 10[superscript 6]. We propose that this high-Q micro-trench cavity design can be applied to incorporate a wide variety of novel microcavity materials, including rare-earth-doped films for microlasers, into wafer-scale silicon photonics platforms
Second-harmonic generation in silicon waveguides strained by silicon nitride
Silicon photonics meets the electronics requirement of increased speed and bandwidth with on-chip optical networks.
All-optical data management requires nonlinear silicon photonics. In silicon only third-order optical nonlinearities are present
owing to its crystalline inversion symmetry. Introducing a second-order nonlinearity into silicon photonics by proper material
engineering would be highly desirable. It would enable devices for wideband wavelength conversion operating at relatively low
optical powers. Here we show that a sizeable second-order nonlinearity at optical wavelengths is induced in a silicon waveguide
by using a stressing silicon nitride overlayer. We carried out second-harmonic-generation experiments and first-principle
calculations, which both yield large values of strain-induced bulk second-order nonlinear susceptibility, up to 40pm/V at
2.300 nm. We envisage that nonlinear strained silicon could provide a competing platform for a new class of integrated light
sources spanning the near- to mid-infrared spectrum from 1.2 to 10 micron
Second-Harmonic Generation in Silicon Nitride Ring Resonators
The emerging field of silicon photonics seeks to unify the high bandwidth of
optical communications with CMOS microelectronic circuits. Many components have
been demonstrated for on-chip optical communications, including those that
utilize the nonlinear optical properties of silicon[1, 2], silicon dioxide[3,
4] and silicon nitride[5, 6]. Processes such as second harmonic generation,
which are enabled by the second-order susceptibility, have not been developed
since the bulk vanishes in these centrosymmetric CMOS materials.
Generating the lowest-order nonlinearity would open the window to a new array
of CMOS-compatible optical devices capable of nonlinear functionalities not
achievable with the? response such as electro-optic modulation, sum
frequency up-conversion, and difference frequency generation. Here we
demonstrate second harmonic (SH) generation in CMOS compatible integrated
silicon nitride (Si3N4) waveguides. The response is induced in the
centrosymmetric material by using the nanoscale structure to break the bulk
symmetry. We use a high quality factor Q ring resonator cavity to enhance the
efficiency of the nonlinear optical process and detect SH output with milliwatt
input powers.Comment: 4 pages, 3 figure
Cmos Backend Deposited Silicon Photonics - Material, Design, And Integration
Silicon photonics has the potential to enable continued scaling of computing performance by providing efficient high speed interconnects within and between logic processors, memory, and other peripherals, which are currently limited by fundamental limits of RF attenuation and spatial bandwidth density of electrical interconnects. However, the path to high performance, cost effective, and scalable integration of silicon photonics with CMOS microelectronic components has not been clear. In this dissertation, we present the vision of the Backend Deposited Silicon Photonics (BDSP) platform that can seamlessly integrate silicon photonics with CMOS microelectronics without disrupting the CMOS fabrication process. Every aspect of BDSP platform, including excimer laser annealed polycrystalline silicon, low loss silicon nitride waveguide, modulator, detector, electrical interface, backend CMOS compatibility, and 3D waveguide integration, is discussed in detail. We experimentally demonstrate key components of the backend deposited silicon photonics platform. We experimentally establish the post processing thermal budget limit for a 90 nm bulk CMOS process as 400? C for 90min. We then demonstrate fabrication of high quality passive polysilicon optical resonators with quality factors above 12,000 using excimer laser anneal. Building on this work, we demonstrate gigahertz electro-optic polysilicon modulator compatible with CMOS backend integration and also show photodetector operation. Optical resonators and waveguides monolithically integrated on CMOS and 3D integration of silicon nitride waveguide and polysilicon waveguide are also demonstrated. In addition, we demonstrate quasi-linear electro-optic phase modulation in silicon using optical mode and PN junction engineering. Finally, results are summarized and possible future works based on BDSP are discussed. This demonstration of the proposed backend deposited silicon photonics opens up a whole new horizon to silicon photonics integration on CMOS. By decoupling CMOS fabrication from photonics fabrication, we lower the barrier to introducing silicon photonics into CMOS foundries and potentially accelerate the adoption of silicon photonics
A SiGe Slot Approach for Enhancing Strain Induced Pockels Effect in the Mid-IR Range
[EN] Strained silicon was proposed more than a decade ago promising to revolutionize the silicon photonics field by allowing efficient modulation in this platform. Despite all the efforts, still rather low chi(2) values have been measured in strained silicon devices. In addition, the way of applying strain has not barely changed since the concept was proposed, usually consisting on a silicon waveguide covered by a stressor material such as silicon nitride. In this letter, a SiGe slot approach is explored as a different route to enhance the strain induced Pockels effect in the mid-IR range. Such approach would allow effective index change values which are near to 10(-4) and improve the values expected for the most common silicon - silicon nitride structure by more than three orders of magnitude.This work was supported in part by the Ministerio de Ciencia e Innovacion under Grant TEC2016-76849 and Grant PID2019-111460GB-I00 and in part by the Generalitat Valenciana under Grant PROMETEO/2019/123.Olivares-Sánchez-Mellado, I.; Sanchis Kilders, P. (2021). A SiGe Slot Approach for Enhancing Strain Induced Pockels Effect in the Mid-IR Range. IEEE Photonics Technology Letters. 33(16):848-851. https://doi.org/10.1109/LPT.2021.3075753848851331
Colloidal quantum dots enabling coherent light sources for integrated silicon-nitride photonics
Integrated photoniccircuits, increasingly based on silicon (-nitride), are at the core of the next generation of low-cost, energy efficient optical devices ranging from on-chip interconnects to biosensors. One of the main bottlenecks in developing such components is that of implementing sufficient functionalities on the often passive backbone, such as light emission and amplification. A possible route is that of hybridization where a new material is combined with the existing framework to provide a desired functionality. Here, we present a detailed design flow for the hybridization of silicon nitride-based integrated photonic circuits with so-called colloidal quantum dots (QDs). QDs are nanometer sized pieces of semiconductor crystals obtained in a colloidal dispersion which are able to absorb, emit, and amplify light in a wide spectral region. Moreover, theycombine cost-effective solution based deposition methods, ambient stability, and low fabrication cost. Starting from the linear and nonlinear material properties obtained on the starting colloidal dispersions, we can predict and evaluate thin film and device performance, which we demonstrate through characterization of the first on-chip QD-based laser
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