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In this paper we show that low energy ion implantation of lnP based heterostructures for quantum well intermixing is a promising technique for photonic integrated devices. In order to fabricate complex optoelectronic devices with a control of the bandgap profile of the heterostructure there is a list of requirements that have to be fulfilled. We have fhhricatcd high quality discrete blueshifted laser diodes to verify the capability of low energy ion implantation induced intermixing fbr integration. We also fabricated extended cavity lasers with this technique, which demonstrated a reduction of the propagation losses down to 5.3 cm' within the integrated passive waveguides.

A new quantum-well intermixing process in InGaAs-InGaAsP structures, based on controlled low energy phosphorus (P) ion implantation, has been employed in the fabrication of multiple wavelength selective channel electroabsorption (EA) intensity modulators. These modulators, fabricated on a single chip, have an intensity modulation depth as high as -1 1 dB for voltage swings as low as -6 V.

InGaAs/InGaAsP quantum well structures have wide applications, such as the integration of optoelectronic devices and low threshold current density lasers, as well as low loss waveguides and optical switching elements. In many cases, high temperature operations (such as during selective area epitaxy or regrowth) are necessary during the course of processing a wafer. Here, we report the influence of low and high etch pit densities (EPD) InP substrates on the thermal stability of InGaAs/InGaAsP quantum well laser structure. Both the n-type of S-doped (EPD

Neutral impurity induced quantum well intermixing (QWI) is an attractive and promising postgrowth bandgap engineeringprocess for the fabrication of photonic integrated circuits (PICs), as it introduces no additional electrical active dopants intothe material system after intermixing. Here, we report the development of neutral impurity induced QWI processes inInGaAs-InGaAsP laser structure using low energy, i.e. 36OkeV, arsenic and phosphorous ion implantation. The samples wereimplanted at room temperature and 200 °C, with a dose range between 1012 and 1014 ions/cm2. The QWI stage was carried outby annealing the implanted samples at 650 °C for 120 s. Samples implanted at 200 °C give higher degree ofQWI. Comparedto P implanted samples, larger bandgap shift was observed from As implanted samples after annealing. A differential PLbandgap shift as large as 93 nm (60 meV) was observed from samples implanted with iO' ions/cm2 of As. Bandgap tunedlasers fabricated from intermixed samples; the current threshold density of the intermixed lasers slowly increases with theamount of blueshift and is kept below 20% for the most blueshifted devices. The attractive device characteristics of thebandgap tuned lasers show that damage induced by the ion implantation can be almost fully treated after annealing. Thisimplies that the material remains in good quality after QWI.Keywords: Low energy ion implantation, quantum well Intermixing, InGaAs-InGaAsP, quantum well laser.