Monolithic integration of erbium-doped amplifiers with silicon-on-insulator waveguides

Monolithic integration of Al2O3:Er3+ amplifier technology with passive silicon-on-insulator waveguides is demonstrated. A signal enhancement of >7 dB at 1533 nm wavelength is obtained. The straightforward wafer-scale fabrication process, which includes reactive co-sputtering and subsequent reactive ion etching, allows for parallel integration of multiple amplifier and laser sections with silicon or other photonic circuits on a chip

Heterogeneous integration of KY(WO4)2-on-glass : a bonding study

Rare-earth ion doped potassium yttrium double tungstate, RE: KY(WO4)(2), is a promising candidate for small, power-efficient, on-chip lasers and amplifiers. There are two major bottlenecks that complicate the realization of such devices. Firstly, the anisotropic thermal expansion coefficient of KY(WO4)(2) makes it challenging to integrate the crystal on glass substrates. Secondly, the crystal layer has to be, for example, < 1 mu m to obtain single mode, high refractive index contrast waveguides operating at 1550 nm. In this work, different adhesives and bonding techniques in combination with several types of glass substrates are investigated. An optimal bonding process will enable further processing towards the manufacturing of integrated active optical KY(WO4)(2) devices. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Single-layer active-passive Al₂O₃ photonic integration platform

Amorphous Al2O3 is an attractive platform for integrated photonics, providing active and passive functionalities. We have developed an integration procedure to create active and passive regions at the same level on one wafer. This fabrication process reduces the number of fabrication steps compared to vertical integration of two materials. The main advantage is that all structures are defined within a single photolithography and etching step and are therefore automatically aligned. As a proof of principle, we demonstrated the luminescence of an active ring resonator with passive bus waveguide

Waveguide-coupled micro-ball lens array suitable for mass fabrication

We demonstrate a fabrication procedure for the direct integration of micro-ball lenses on planar integrated optical channel waveguide chips with the aim to reduce the divergence of light that arises from the waveguide in both horizontal and vertical directions. Fabrication of the lenses is based on photoresist reflow which is a procedure that allows for the use of photolithography for careful alignment of the lenses with respect to the waveguides and enables mass production. We present in detail the design and fabrication procedures. Optical characterization of the fabricated micro-ball lenses demonstrates a good performance in terms of beam-size reduction and beam shape. The beam half divergence angle of 1544 nm light is reduced from 12.4° to 1.85°