Passive Alignment Technique Research Articles

High power and high sensitivity planar lightwave circuit module incorporating a novel passive alignment method

A high-power, high-sensitivity planar lightwave circuit (PLC) module, comprising a laser diode (LD) and a photodiode (PD) surface mounted on a PLC platform, has been realized by a novel passive alignment technique. We used a spot-size transformed LD and a corner-illuminated PD to form a highly efficient optical coupling between the devices and a PLC waveguide. We used the unique marker alignment method to ensure accurate positioning of them. The positioning precision achieved in the lateral direction was within 1 /spl mu/m for the LD's and within 10 /spl mu/m for the PD's. The rotational precision was within 0.4/spl deg/ for both chips. We realized high power operation (>8 mW) with a high receiver sensitivity (0.3 A/W). In this paper, we describe a high power, high sensitivity PLC incorporating a novel passive optical alignment technique for LD's and PD's.

Low cost, integrated 4-element laser arrays withpassive fibre alignment for optical data communications links

The design, fabrication and characterisation of 4-element laser arrays operating at 1300 nm for use in low cost data communication links is described. The design of the chip and package incorporated flip-chip solder bonding to achieve passive alignment of the laser elements to optical fibre. Individual elements exhibited lasing threshold currents of <20 mA with output powers > 30 mW at a drive current of 100 mA. Coupling efficiencies of up to 10% into singlemode optical fibre were achieved by laser modules fabricated using passive alignment techniques. At a drive current of 70 mA, the small signal 3 dB bandwidth of the devices was 5 GHz.

Passive alignment of second generation optoelectronic devices

This paper details how expanded-mode semiconductor devices and passive alignment techniques can be used to realize low-cost high-performance fiber grating laser and laser amplifier packages for future generations of optical telecommunication systems.

Reliable wide-temperature-range operation of 1.3-μm beam-expander integrated laser diode for passively aligned optical modules

A novel structure for a 1.3-/spl mu/m beam-expander integrated (BEX) laser diode is demonstrated. It combines a thickness-tapered InGaAsP-InP multiple quantum-well (QW) crystal grown by a novel silicon shadow masked metalorganic vapor phase epitaxy and a simple reverse-trapezoid-ridge waveguide laser structure that offers smooth mode field expansion and improved high-temperature lasing performance. We found this new BEX laser quite suitable for operation over a wide range of temperatures above 85/spl deg/C and highly efficient lens-free coupling to a single-mode fiber (SMF) of less than 3 dB. These excellent lasing properties along with reliability under severe environmental conditions make this BEX-LD a promising candidate for practical use for low-cost long-wavelength light-source modules using optical passive alignment techniques.

Hybrid integration of spot-size converted laser diode on planar lightwave circuit platform by passive alignment technique

An index alignment technique was developed for a planar lightwave circuit platform. The technique was successfully applied to the hybrid integration of a spot-size converted laser diode on the platform. The fabricated modules exhibited an average coupling loss of 4.2 dB and a maximum optical output power of 10 mW at an injection current of 70 mA.

A surface mount single-mode laser module using passive alignment

A novel single-mode laser module has been developed using a surface mounting technique. A simple receptacle structure for the module output port is also designed. This module offers high coupling efficiency and optical coupling using the passive alignment technique. A module size of 7.6 mm/spl times/12 mm/spl times/3 mm is achieved, which is very friendly for the automatic assembly line as well as the module mounting process on circuit boards. A laser diode (LD) is passively positioned by utilizing a pair of alignment marks, each of which located on the LD and Si substrate, a single-mode fiber with a microhemispherical lens on the fiber facet is self-aligned on a Si-V groove. The LD to single-mode fiber coupling loss and standard deviation are found to be 5 dB and 1.5 db, respectively. The simple receptacle structure enables one to use this module in the same way as conventional surface mount electrical components. The module assembly process is simplified by successively mounting subassembly parts.

Silicon waferboard-based single-mode optical fiber interconnects

In an extension of previous work, hybrid integration utilizing silicon waferboard platforms has been shown to be useful in building complete single-mode, optical fiber interconnect links. The fabrication and testing of high-performance optical interconnect array transmitter modules and receiver modules is described in this paper. The silicon waferboards include alignment features for passively aligning laser arrays and turning mirrors for backside illumination of metal-semiconductor-metal (MSM) detectors. Transmission rates of 1.4 Gb/s per fiber over single-mode optical fiber have been demonstrated. The four-channel link developed in this work was tested over a distance of 1 km and exhibited a link margin of greater than 11 dB. The bit error ratio was less than 10/sup -12/ and the crosstalk for adjacent channel traffic was about -20 dB at 1 GHz. This effort has confirmed the feasibility of employing silicon waferboard passive optical alignment techniques to potentially lower the cost of high speed optical interconnects.

Packaging of high-density fiber/laser modules using passive alignment techniques : Mitchell S. Cohenet al. IEEE Transactions on Components, Hybrids, and Manufacturing Technology, 15(6), 944 (1992)

Packaging of high-density fiber/laser modules using passive alignment techniques : Mitchell S. Cohenet al. IEEE Transactions on Components, Hybrids, and Manufacturing Technology, 15(6), 944 (1992)

Hybrid integration of semiconductor lasers with Si-based single-mode ridge waveguides

Hybridization is a convenient way for providing silicon-based integrated optical circuits with a laser source. An entirely passive alignment technique exclusively based on the high precision obtainable by lithography and by semiconductor processes was examined. A novel way of cleaving the laser chips by self-aligned cleaving grooves was employed. It resulted in 15.5-dB coupling losses between the laser diode and the single-mode buried ridge waveguide. >