SBIR-STTR Award

This Phase I Small Business Innovation Research describes a means to develop a misalignment-tolerant fiber-optic laser transmitter. The insensitivity to misalignment within the transmitter optical subassembly (OSA) enables passive alignment to single-mode fibers for extremely low-cost, high-performance applications such as fiber-to-the-desk (FTTD) and network access modules. The OSA is based on vertical-cavity surface emitting lasers (VCSELs). Critical issues and a method for producing the passively-aligned OSA are presented in the proposal. The Phase I program will fabricate prototypes, evaluate the ease of assembly, test for tolerance to misalignment, test for opto-mechanical robustness, and examine further issues. The proposed OSA is equally applicable to VCSEL-based transmitters and high-performance photoreceivers. Results of all these activities will determine the feasibility of manufacturing passively-aligned transmitters by the proposed method. If the method appears feasible, Phase II program will be proposed to optimize the parameters for the various elements of the package and develop an efficient fabrication process. Ruggedness and reliability tests will also be performed in Phase II. The proposed transmitters/receivers would deliver laser performance at LED costs. VCSEL-appropriate, single mode, telecom transmitter and receiver modules combine for >$1B/year markets in the year 2003 with high growth rate. High-performance datacom could add several hundred million/year in addition. Short-wavelength VCSEL packages are useful for barcode scanners and pointers.

This Phase II Small Business Innovation Research proposal aims to develop a revolutionary multi-mode optical sub-assembly (MMOSA), I.e. a laser or detector having external electrical connections and which has efficient optical coupling with a 62.5um core fiber. The proposed MMOSA is distinguished from existing technology in that it: 1) does not require the laser or detector to be activated for alignment (I.e. it is passively aligned); 20 lends itself to plastic encapsulated lead-frame packaging; and 3) should have an overall cost which is drastically reduced. Other advantages of the MMOSA are detailed in the proposal, which also distinguish it from existing technology. The Phase II program builds upon innovative packaging concepts laid out and simulated in Phase I. It will comprise two iterations of detailed opto-mechanical component fabrication; experimental tolerance testing; MMOSA assembly; yield analysis; and reliability testing. The second iteration will be far more rigorous than the first and is expected to yield a packaging process suitable for meeting Gigabit Ethernet and Fibre-Channel standards.

Keywords:
Surface-Emitting Lasers; Multi-Mode Transciever Modules; Passive Alignment; Gigabit Ethernet; Data C