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The extension of a photonic integrated circuit foundry process flow is proposed by integrating selective area growth (SAG) to enable bandgap tuning for each individual active building block. The process adaptations and the impact on performance are reviewed in terms of morphology requirements and topology reduction. This platform extension enables bandgap tuning for a set of active devices to cover the wavelength range from 1453 to 1651 nm. Integration is demonstrated in combination with active-passive butt-joint technology to create the most comprehensive range of generic building blocks. Performance and limitations of the range of achievable band-edges within the same monolithic wafer are studied for amplifiers and extended cavity lasers.

Monolithic photonic integrated circuits (PIC) transmitters using the prefixed optical phase switching concept for BPSK modulation format have been shown promising at 1.55 μm band. These devices could also be crucial for short reach connections and access networks. With this aim, we are studying basic quantum well designs for a laser and an electro-absorption modulator switch to be integrated by selective area growth into PICs at 1.3 μm. Photocurrent measurements and band offset modeling have been performed to determine the MQW stack well-fitted for this application. Broad area laser measurements have also been checked on these structures to verify the material lasing properties. A 6 nm thick well with low barrier seems to be the best trade-off between absorption and shift for 1.3 μm EAM and it also gives good lasing properties.

An array of monolithic wide-tunable lasers is integrated using selective area growth to shift the bandgap of their gain section. A gap-free tuning is demonstrated from the combination of the tuning ranges of the lasers, and single-mode operation is verified.

Selective area growth is used for the first time in the TU/e generic integration platform to modify independently the bandgap of active sections. A chip combining 4 tunable lasers with shifted wavelength ranges has been fabricated. A 96 nm wide tuning range is demonstrated.

We report on a fully integrated hybrid III-V on silicon distributed feedback laser integrated with a ring resonator, which enables direct modulation at 25 Gb/s with 20dB optical budget at 20km and 5dB extinction ratio.

We report, for the first time, a transmission experiment over standard fiber at 1.55 μ m using an electroabsorption modulated laser (EML) integrated with a semiconductor optical amplifier (SOA). We show clearly that negative pre-chirped signals can be obtained by adjusting both modulator and amplifier driving parameters. Negative chirp operation is evaluated through small-signal chirp measurement as well as through time-resolved dynamic chirp measurement. Signal chirp control at emission enhances transmission and increases optical reach. Thanks to the SOA gain and chirp compensation for modulator loss and chirp, dispersion-penalty-free with clear open eye diagrams over 100 km of optical fiber at 10.3 Gb/s is achieved. A transmission up to 125 km is also obtained. This novel fully integrated EML-SOA is very promising as a high-performance, compact and low-cost optical transmitter for the future access-metropolitan network convergence.

The use of industrial micro x-ray diffraction (μ-XRD) allows us to access composition and thickness of multiple quantum well (MQW) made by selective area growth (SAG). To make high performance photonic integrated circuit (PIC), a precise design of dielectric masks is mandatory for the SAG process. μ-XRD measurements point out some unpredicted behavior compared to our previous modeling like indium enrichment. Thus a new model is now developed, based on the Kardar-Parisi-Zhang (KPZ) equation which takes into account other phenomena occurring during SAG, like surface migration and relaxation patterns.

10Gb/s directly modulated tunable lasers, integrating chirp management ring resonators, have been designed and fabricated using wafer bonding. Using such a device, we demonstrated error-free transmission over 50km single mode fiber.

We report on the thermal design and the characterization of InP-based 1.55 μm wavelength large diameter (∼100 μm) optically pumped vertical external cavity surface emitting lasers (OP-VECSELs). The device is thermally optimized for high power ( > 70 mW) room-temperature (RT) continuous-wave (CW) single-mode operation. Efficient bottom heat dissipation in the 1/2-VCSEL chip is obtained thanks to the use of a hybrid metal– metamorphic GaAs/AlAs mirror integrated to the InP-based active region, and to subsequent soldering on a SiC substrate. A single-mode output power of 77mW is obtained under CW-RT laser operation, limited by the pump power. Moreover thermal simulations and characterizations of the 1/2-VCSEL chip show that even higher power could be obtained at higher pumping levels, using a CVD diamond substrate.

Thickness and composition profiles of AlGaInAs-based layers grown by low-pressure metal organic vapour phase epitaxy in the regime of selective area growth (SAG) have been modelled and measured experimentally. Experimental thickness profiles of InP, GaAs and GaAlAs bulk layers grown in the SAG regime have been precisely fitted with a three-dimensional vapour phase-diffusion model, and the characteristic diffusion length coefficient (D/k) for In, Ga and Al extracted. The D/k diffusion parameter for aluminium has been calculated and found intermediate between the indium and gallium ones. The diffusion model predict both thickness and compositional variations of AlGaInAs layers selectively grown for different mask patterns. The excellent agreement obtained between calculated and measured profiles makes this modelling tool essential for engineering of future SAG integrated optical devices.

The low-pressure metalorganic vapor-phase epitaxy (LP-MOVPE) of tensile AlGaInAs multi-quantum wells (MQWs) for transverse magnetic (TM) 1.3 μm emitting lasers is presented. Al-containing wells have been mostly studied with compressive strain for transverse electric (TE) lasers. In this study, we report on highly tensile-strained AlGaInAs well layers (−0.72 to −1.65%) grown with compressive-strained AlGaInAs barrier layers (0.64%). The good agreement of high-resolution X-ray curves and simulated curves indicates that good crystalline quality and abrupt hetero-interfaces are obtained. An enhanced separation between light hole and heavy hole transitions is clearly observed by room-temperature photoluminescence as the strain increases. From broad-area laser results, it was observed that the strain had a low impact on the laser internal loss, the quantum efficiency and the transparency current density, which was as low as 0.32 A/cm 2 for a 6 QW structure. On the opposite, a doubling of the gain parameter g 0 when the strain increases from −0.72 to −1.65% was clearly observed. This result is associated with a 40% threshold density reduction on 300 μm long lasers. These investigations show that highly tensile-strained layers are very promising for the realisation of high-speed lasers.

Compact parallel transmitters and receivers with an aggregate capacity of 107 Gb/s are built through hybrid integration of arrays of ten 100-GHz spaced directly modulated lasers, arrays of ten avalanche photodiodes, and high-index contrast silica arrayed waveguide grating multi- and demultiplexers. Unamplified transmission over 75 km of standard single-mode fiber and 155-km amplified links is demonstrated in the C-band, by using a modulation format based on spectral offset filtering and electronic dispersion compensation.

We demonstrate an AlInAs-InGaAs separate absorption, grading, and multiplication avalanche photodiode (APD) with a very thin avalanche layer operating at 1550 nm for 10-Gb/s optical transmission achieving simultaneously high responsivity (0.9 A/W at M = 1), very low excess noise factor (F(M=10) = 3), and very high gain-bandwidth product of 240 GHz. To our knowledge, this is the first time that a back-side illuminated planar junction AlInAs-InGaAs APD achieved such performances.

This letter presents a comparative study of GaInAs-AlInAs avalanche photodiodes with different absorption layer thicknesses. Simulations concerning dark current and frequency response have been carried out to study the influence of the vertical structure on functional characteristics. Fabricated devices achieved gain-bandwidth product GtimesB as high as 180 GHz combined with very low dark current and low excess noise factor.

We developed a 10-Gb/s AlGaInAs colorless remote amplified modulator with a gain peak detuned semiconductor optical amplifier using a selective epitaxy and semi-insulating buried heterostructure. The device provides up to 10-dB insertion gain and lossless operation together with static extinction ratio larger than 20 dB over a 50-nm range. Using this device, we achieved 10-Gb/s remote modulation over 80-nm spectral range in a back-to-back transmission. The device operates also in a single-mode fiber bidirectional link without penalty at 20 $^{\circ}$ C.

This letter demonstrates a planar junction GalnAs-AlInAs avalanche photodiode using back-side illumination through thinned InP substrate covered with chemical vapor deposition SiNx antireflection coating. The combined properties of very low dark current (I dark(M = 0) = 17 nA), low excess noise factor (f(M = 10) = 3.5), and high gain x bandwidth product over 140 GHz were simultaneously achieved with a high primary responsivity of 0.95 A/W at 1.55 mum.

International audience; In this work, selective area growth has been used for the realization of InP based photonic integrated circuits (PICs). To predict the strain, thickness and bandgap energy variations over large and high-density multifunctional arrays, it is necessary to precisely design the shapes and positions of the dielectric masks by computational modeling. To address the mask layout density and complexity in both longitudinal and transversal direction, the use of three dimensional vapor phase model was mandatory. In each SAG region used for individual component processing, the calculated data were compared to experimental ones acquired by synchrotron-based microbeam x-ray diffraction and by micro-photoluminescence wavelength mapping. The excellent result concordance shows that both advanced modeling and characterization techniques are of importance for PIC conception and fabrication.

Selective area growth enables to locally tune the epitaxial material thickness and composition on a single InP substrate. This paper presents this technology and its application to photonic integrated circuits, illustrated by two realisations.

SWIR image sensors based on p-i-n photodiodes arrays present a tremendous interest in applications often requiring a high intra-scene dynamics. This paper describes a single-chip InGaAs SWIR camera with more than 120 dB intrinsic operational dynamic range with an innovative CMOS ROIC technology initially developed by New Imaging Technologies for visible CMOS camera chip. A simplified camera with on chip fixed pattern noise correction is presented. We also present the next generation of focal plane arrays (FPA) based on a VGA format of 640 x 512 pixels with a pitch of 15 μm. These FPAs are associated to a logarithmic wide dynamic range ROIC. We give the electro-optics performances and particularly the visible extension capabilities. This InGaAs VGA logarithmic single-chip camera allows a high resolution SWIR camera with minimized system complexity and low power consumption.

Thermal optimization of 1.55 mum VECSELs is studied in term of bottom Bragg mirror structure. 125 mW room temperature rollover-free output power is produced from a hybrid metal-metamorphic mirror structure bonded onto a diamond substrate.

We demonstrate a planar junction AlInAs APD using Carbon as p-doping impurity of the charge layer allowing to achieve simultaneously a high primary sensitivity of 0.9 A/W, a low dark current (Idark(M=10)=17 nA at ambient temperature), a low excess noise factor (f(M=10)=3.5) and high gaintimesbandwidth product over 140 GHz.

A selective area growth model was used to engineer a remote amplified modulator with an AlGaInAs multi-quantum well active layer. The selective mask layout was designed to fulfill special component requirements including +35 nm SOA gap detuning and low polarization dependence. The fabricated reflective device exhibits 10 dB maximum insertion gain and operates at 10 Gbit/s over 80 nm spectral range.

We studied the Selective Area Growth of AlGaInAs Multiple Quantum Wells for wide wavelength range applications such as Coarse Wavelength Division Multiplexing. A 3-D vapor phase diffusion model is used to simulate the complete set of mask patterns. Due to high mask density, the long-range effect of Ga and Al compared to In species is a limiting parameter for the total achievable wavelength extension. Based on these simulations, we predicted and experimentally obtained a total PL wavelength shift of 240 nm.

We integrated an AlGalnAs modulator-amplifier using semi-insulating buried hetrostructure and selective area growth. The reflective component exhibits insertion gain, operates at 10Gbit/s over 80nm and links bi-directional 10km SMF up to 60°C.

We studied the selective metal-organic vapor-phase epitaxy of thick InP bulk layers. The work focused on the obtention of planar thick layers by an adjustment of the growth conditions. We showed that reduced pressure and temperature in the reactor allowed to decrease the sharpness of the thickness profiles in the vicinity of the mask. This approach is consistent with the vapor phase diffusion model and the kinetic theory. Thick InP layers generally show huge overgrowths at the edges of the dielectric stripes. These overgrowths were suppressed by reducing the growth rate. All samples’ thickness profiles were characterized by means of optical interferometer microscopy and surface profiler. Scanning electronic microscopy was used in the observation of the edge overgrowths and highlighted the complexity and anisotropy of the growth at these edges.

We studied selective area growth modeling and characterization of the AlGaInAs material system. We used a three-dimensional vapor phase diffusion model to extract the effective diffusion lengths of Al, Ga, and In species from measured thickness profiles of the three binaries AlAs, GaAs, and InP. Our growth conditions yield to 50, 85, and 10 μm for Al, Ga, and In, respectively. Based on these values, we achieved a precise prediction of AlGaInAs thickness, composition, band gap, and biaxial strain variations in different selective area growth conditions. Particular attention was paid to the influence of neighboring cells in the case of high mask density. This configuration occurs in practical component mask layout. High mask density leads to interferences between masked cells and enhances the effect of the long diffusion length of aluminum and gallium species. Then, the biaxial strain is tensile shifted and the band gap is blue shifted in the vicinity of a mask, compared to reference material features grown...

New self thermal compensated Single Active Layer AlGalnAs EML demonstrates 43 Gb/s open-eye operation for temperatures ranging between 10°C and 70°C. The dynamic extinction ratio over the whole temperature range was above 10 dB.

Large positive detuning is used for self thermal compensation of threshold and power variation in AlGalnAs DFB. 25 km uncompensated and non-amplified SMF transmissions are demonstrated at a constant bias current from 20°C to 90°C.

Thicknesses and compositions of AlGaInAs-based layers grown by low-pressure metal-organic vapor-phase epitaxy (LP-MOVPE) in the regime of selective area growth (SAG) have been measured and calculated. In this study, we have grown InAs, GaAs and AlAs binary bulk layers on patterned InAs and GaAs substrates, respectively, in order to assess separately the vapor-phase diffusion (VPD) length (D/k) of indium, gallium and aluminum species. Special care has been taken in the evaluation of the Aluminum D/k ratio, on which little information was available. A 3D VPD model has been used to predict the composition and thickness profiles of various alloys. The calculated profiles have been compared to the experimental ones for GaInAs, AlInAs, AlGaInAs layers and GaAlAs layers deposited on patterned InP and GaAs substrates, respectively. The good agreement between modeling and experiment, together with the perfect selectivity obtained for all the different alloys, holds for the validity of the calculated D/k ratio of Al, Ga and In species. In MOVPE-SAG, the efficiency of a computational model is a key issue for the engineering of future SAG integrated optical devices.

We demonstrate a back-illuminated planar AllnAs APD. We obtain a low excess noise factor of 4 at M=10 measured with an accurate noise characterization method and a high bandwidth over 10 GHz (M=1.5 to 7).

Single Active Layer is used for self thermal compensation of threshold and power variation in AlGalnAs EML. 90km SMF up to 60°C and 50km SMF up to 70°C trans missions are demonstrated.

By enhancing excitonic absorption in a new design of a polarization independent EA modulator, a 50 nm flat absorption spectrum, 42 GHz bandwidth devices together with 14-30 dB/V modulation sensitivity are obtained for 75 /spl mu/m long devices.

CLEO subject 8 "Ultrafast Optics, Optoelectronics and Applications", technical session CThD "Ultrafast Switches" [CThD3]; International audience; We report on a novel quantum well saturable absorber device whose measured response time of 1.5 psec and contrast of at least 4 dB make it suitable for all-optical extinction ratio enhancement at 160 Gbit/s.

Short-wavelength infrared image sensors based on p-i-n photodiode arrays present a tremendous interest in applications such as passive and active imagery for laser detection/warning, hot spot or detection for lasers sensors, enhanced vision systems or low light level sensors. The capability to work at room temperature with dark current equivalent to silicon-based devices is another motivation for the fast development of this technology. This paper presents several modules and camera based on InGaAs photodiode arrays from the III-VLab. First, we describe the electro-optics performance in terms of dark signal, sensitivity, and particularly the visible extension capability. We also present a nucless logarithmic sensor based on a 1/2 video graphics array (VGA) format at a pitch of 25 μm initially designed for visible CMOS camera chip. We will also present the next generation of focal plane arrays based on a VGA format of 640×512 pixels with a pitch of 15 μm. This array will be associated to a CTIA readout circuit and also to an innovative CMOS logarithmic wide dynamic range ROIC, developed by New Imaging Technologies. This VGA logarithmic device developed for automotive safety will involve visible extension capability in a European project named 2Wide_sense.