For about ten years, we have been developing InP on Si devices under different projects focusing first on µlasers then on semicompact lasers. For aiming the integration on a CMOS circuit and for thermal issue, we relied on SiO2 direct bonding of InP unpatterned materials. After the chemical removal of the InP substrate, the heterostructures lie on top of silicon waveguides of an SOI wafer with a separation of about 100nm. Different lasers or photodetectors have been achieved for off-chip optical communication and for intra-chip optical communication within an optical network. For high performance computing with high speed communication between cores, we developed InP microdisk lasers that are coupled to silicon waveguide and produced 100µW of optical power and that can be directly modulated up to 5G at different wavelengths. The optical network is based on wavelength selective circuits with ring resonators. InGaAs photodetectors are evanescently coupled to the silicon waveguide with an efficiency of 0.8A/W. The fabrication has been demonstrated at 200mm wafer scale in a microelectronics clean room for CMOS compatibility. For off-chip communication, silicon on InP evanescent laser have been realized with an innovative design where the cavity is defined in silicon and the gain localized in the QW of bonded InP hererostructure. The investigated devices operate at continuous wave regime with room temperature threshold current below 100 mA, the side mode suppression ratio is as high as 20dB, and the fibercoupled output power is ~7mW. Direct modulation can be achieved with already 6G operation.

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This paper deals with the realization of a 1 .3/1 .55 xm duplexer integrated on a silica on silicon substrate. The design consists of two cascaded directional couplers in order to enhance the rejection bandwidth. Fabrication is based on plasma enhanced chemical vapor deposition (PECVD) and reactive ionic etching (RIE) of silica films. The channel guide structure has been optimized to comply with the small distance between guides along the coupler, that would still ensure low loss fiber coupling. The results show an excellent spectral response : insertion loss lower than 3 dB on a 150 nm bandwidth at both wavelengths, crosstalk as low as 20 dB on a 100 nm bandwidth. Moreover, quite a total independance on polarization and temperature has been checked, for the required 1,3/1 ,55 urn separation.