A. Pinquier

MSI InP/InGaAs DHBT technology: beyond 40 Gbit/s circuits

We present current results obtained on IC-oriented OPTO+ InP DHBT lab technology. Transistors with 180/210 GHz F/sub t//F/sub max/, current gain of 50 and BV/sub ce0/=7V are currently fabricated with >99% fabrication yield. Uniformity measurements show a standard deviation on F/sub t/ and F/sub max/ lower than 2% and lower than 5% on all investigated parameters. In a second part DHBT-specific modelling issues are discussed. A 68 Gbit/s selector has been obtained and a 40 Gbit/s master-slave D-type flip-flop (MS-DFF) has been reproducibly fabricated with >50% functional yield using this technology.

How to launch 1 W into single-mode fiber from a single 1.48-/spl mu/m flared resonator

The operation of 1.48-/spl mu/m flared resonators is thoroughly studied, both experimentally and theoretically: the accurate determination of threshold condition as a function of geometrical and material parameters, the study of emission spectra and astigmatism variations as a function of optical power level allow us to better understand the may these devices operate. The origin of modal distortion is then analyzed, and an original solution is proposed to increase the single-transverse-mode power at high injection level: it is shown that implanting the multiple-quantum-well active layer with protons efficiently enhances the filtering capability of the overall structure, and particularly that of the ridge waveguide, by bringing additional lateral absorption losses. The explanation of the filtering mechanism is successfully confirmed by simulations using the beam-propagation method. This technique finally allowed more than 1.3 W of continuous wave (CW) diffraction-limited power at 6 A. Low-modal-gain structures were then realized to reduce modal optical absorption in the implanted structures with a view to maintaining a high external efficiency and a reduced vertical divergence. Finally, a three-lens coupling system was designed and the effects of optical feedback minimized so as to obtain a very high coupling efficiency: with an improved laser design, 1.12 W of CW power were then coupled into single-mode fiber at 6.6 A, which represents 65% of the power emitted by the laser chip.

InP DHBT technology and design for 40 Gbit/s full-rate-clock communication circuits

In this paper, we present our InP DHBT technology with improved performances, yield and uniformity; and some new design tools, both of which have allowed us to achieve 40+ Gbit/s full-rate-clock circuits, such as the D-flip-flop. These circuits have been characterized and packaged.

76-km transmission over standard dispersion fiber at 10 Gbit/s using a high-power integrated laser modulator and a PIN receiver without any optical amplifier

We report a high output power (20 mW) integrated laser-modulator device, which allows 10-Gbit/s transmission with a negative alpha parameter over 76 km of standard fiber without any optical amplifier as a result of an average launched power of +3.6 dBm under modulation conditions.

WDM operation of a hybrid emitter integrating a wide-bandwidth on-chip mirror

A wide-bandwidth on-chip mirror based on a deeply etched Bragg grating localized over 10 /spl mu/m is presented; it exhibits reflectivity over more than 25 nm. Integration within a laser-Mach-Zehnder modulator is shown and the wavelength-division multiplexing capability of the device demonstrated in a hybrid Bragg reflector configuration, by showing operation of the same InP chip with fiber gratings from 1534 to 1558 nm.

CH/sub 4//H/sub 2//N/sub 2/ reactive ion beam etching for InP based photonic devices

Improved dry etching techniques are crucial for the fabrication of state-of-the-art photonic devices on indium phosphide. One important area is monolithic integration of advanced functions combining ridge and butt-coupling technologies. Reactive ion etching (RIE) of InP-based materials at room temperature with hydrocarbon chemistry is well recognized as an efficient tool, especially for controlling fine pattern etching and anisotropy. Reactive ion beam etching has been studied as an alternative to RTE for which ion energy and current density cannot be controlled independently. This new tool is mainly expected to lead to better etch uniformity on 2-inch InP wafers, to a better control of sidewall angles and a reduction in etched-induced damage. It is currently used with high reproducibility for laser fabrication with methane, hydrogen and argon. In this paper we present process improvements based on nitrogen introduction to reduce polymer deposition. We then show some applications to advanced photonic devices.

1.1-W continuous-wave 1480-nm unstable-cavity lasers with distributed electrodes for mode shaping

The distributed electrode enables to reduce spatial hole-burning effects, therefore improving the modal behavior of diffraction-limited MQW lasers. We report the first realization of such devices emitting 1.1 W nearly single mode at 1480 nm.

Novel 1.55 /spl mu/m VCSELs with top metamorphic GaAs/GaAlAs and bottom InP/InGaAsP Bragg reflectors

A novel 1.55-/spl mu/m surface-emitting laser structure based on a tunnel junction for current injection and GaAs-AlAs top mirror directly grown on InP cavity in a 2 in. compatible process allows cw operation at room temperature.

Wide bandwidth on-chip mirror for WDM emitters: integration with a laser Mach-Zehnder modulator

A wide bandwidth on-chip mirror using deeply etched Bragg gratings localised over 10 /spl mu/m is presented; it enables reflectivity over more than 25 nm. Integration within a laser-modulator structure is shown and the WDM capability demonstrated over 20 nm.

Fabrication of 1.55 /spl mu/m oxidized VCSELs with top metamorphic GaAs/GaAlAs and bottom InP/InGaAsP Bragg reflectors

We present the fabrication of 1.55 /spl mu/m multi-quantum well vertical cavity surface emitting lasers (VCSEL) grown by gas source MBE on InP substrate. We use a combination of lattice-matched InP/InGaAsP and GaAs/GaAlAs metamorphic reflectors with high reflectivities. Room temperature operation in pulsed mode is achieved. We also demonstrate that selective wet oxidation of GaAlAs can be applied to metamorphic material.