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In this paper, recent developments of the InP membrane on silicon (IMOS) photonic integration platform are discussed. High optical confinement and design flexibility provided by this platform enable new applications for future 5G networks. The platform is being developed towards open access, using standardized building blocks (BBs) and a generic process flow.

Recently a uni-traveling carrier photodetector (UTC-PD) with a 3 dB bandwidth beyond 67 GHz was presented [1]. The device shows good performance up to 3 mA of photocurrent but experiences thermal failure (see Fig. 1a) at higher currents due to the poor heat extraction in membrane-type devices. Improvements to the thermal design are proposed that promise to double the possible photocurrent before thermal failure, which makes the performance comparable with state-of-the-art SOI UTC-PDs [2].

We present the design and measurement of a high-density WDM transmitter from a simple, low-cost generic photonic foundry. Monolithic integration of active and passive devices on InP yields a compact circuit with 20 nm tuneability and 30 Gb/s modulation per channel. This results in a chip supporting 180 Gb/s with a high capacity density of 10 Gb/s/mm^2.

We present an experimental study into the use of simple Fabry Perot lasers for integration in generic platforms. Such integrated FP lasers offer the advantage of freedom of placement anywhere on the chip and, easy integration with monitoring and control functions. They can play a role in short range data communications and they have a potential for 10 Gb/s direct modulation speed. We report first results on experimental realization of such lasers including eye diagrams and BER testing results.

In the development of integrated large-scale optical phase array, compact optical nanoantennas are needed. For high resolution arrays, the nanoantenna footprint and the separation between them should be as small as possible to reduce the number of interference orders in the far field [1]. In the development of this nanoantennas in our InP membrane on Silicon (IMOS) platform [2], we use deeply etch focusing grating to reduce the size [3]. In order to increase the optical power emitting up, we add a metal reflector of Silver underneath the semiconductor with a small buffer of 50 nm of 푆푖푂2. This metal layer will also works as a thermal heater, which will change the optical properties of the semiconductor changing the direction of the upcoming light. The last element to be add is a subwavelength ridge which reduces the unwanted Fresnel reflections by reducing the refractive index contrast [3].

For the InP Membranes On Silicon (IMOS) platform [1], we developed an electrooptic modulator based on a slot-waveguide with a high nonlinear polymer. A variety of fabrication techniques are used, including electron beam lithography (EBL), optical lithography (OL), dry etching and metallization. The fabrication of such modulator requires a complex fabrication process. In this work we present and discuss the most important fabrication steps.

We propose a novel membrane electro-absorption modulator (EAM) integrated on silicon. The device is based on the carrier-concentration dependent absorption of highly-doped n-InGaAs. The modulator is predicted to be wide-band and to provide an extinction ratio (ER) of 7.5 dB, an insertion loss (IL) of 1.1 dB, a modulation speed above 10 Gbit/s and a power consumption of 80 fJ/bit. The modulator has a small footprint of 10 x 120 μm² and operates with a 1.5 V voltage swing.

In this paper we present an electro-optical model for traveling-wave modulator devices utilizing measurement-based equivalent circuit model extraction in conjunction with microwave CAD simulation techniques. Model verification is performed with frequencydomain and time-domain characterization of an integrated Mach-Zehnder modulator from an InP Foundry process.

We experimentally demonstrate how the thermal crosstalk between active and passive components limits the performance of integrated Mach–Zehnder (MZ) modulators operating in the radiofrequency regime. To evaluate the role of the distance between active and passive components, the MZs are placed at different distances with respect to a semiconductor optical amplifier that represents the heat source. The thermal crosstalk is quantified by measuring the effects on the electro–optical response of MZ modulators considered as the test structure. Both extinction ratio and bit error rate degradation are measured. The proposed investigation allows the introduction of design rules, based on the minimum distance between components to ultimately avoid unwanted thermal effects. According to the result provided by our analysis, we also show how the ER degradation can be recovered.

A tunable laser operating from 2011 – 2042 nm realized as a monolithic InP photonic integrated circuit and fabricated within a multi project wafer run is presented. The laser is tuned using an intracavity filter based on nested asymmetric Mach-Zehnder interferometers with electrorefractive modulators. The device is intended for a single line gas spectroscopy and was designed and realized using a generic integration technology.

On-wafer probing of optical signals offers powerful means for assessing the fabrication process quality of photonic integrated circuits. We describe the fabrication and characterization of a vertical optical coupler that enables on-wafer probing.