Chuan Xie

Emcore's 1 Gb/s to 25 Gb/s VCSELs

Emcores 850 nm UltralaseTM VCSELs, operating at a data rate from 1 Gb/s to 25 Gb/s, is presented. They were based on our low-cost and hermetic-by-design chip platform which contains the same element for either singlets or arrays with a 250 μm pitch. First, we discuss high-speed VCSEL evolutions, device designs, manufacturing processes, and device characteristics. Secondly, we present performance of Emcores TOSAs, 40 Gb/s parallel optic modules (S12), 120 Gb/s CXP modules, active connect cables (40 Gb/s QDR and 56 Gb/s FDR), as well as comprehensive reliability qualifications of UltralaseTM VCSELs. Lastly, we briefly go over the recent progress of 20 Gb/s and 25 Gb/s VCSEL developments. We have successfully achieved a 3dB bandwidth of 15 GHz at 85°C and 8 mA for a 7.5 μm aperture UltralaseTM VCSEL.

Exploring the limits of high-speed receivers for multimode VCSEL-based optical links

We present complete characterizations of multimode GaAs photodetectors for high-speed VCSEL-based optical links and compare SiGe receiver IC performances in a 62Gbps back-to-back link for different photodiode designs.

New high speed VCSEL product development at Emcore

In this paper, we summarize the recent VCSEL development effort at Emcore. The focus of this effort is on performance, reliability and manufacturability. We will report the performance of Emcores 14Gbps VCSEL for the new fibre channel application. We will also present the work on manufacturing both singlet and various VCSEL arrays, with performance up to 10Gbps, using a universal mask set to deliver both high performance and high manufacturability. The reliability data and the work on wafer level burn-in will be updated as well.

Development of High-Speed VCSELs Beyond 10 Gb/s at Emcore

We report developments at Emcore on serial 850 nm vertical-cavity surface-emitting lasers (VCSELs) operated up to 25 Gb/s. They have been designed to provide a solution not only to meet stringent 10 Gb/s IEEE and Fiber Channel specifications but also for emerging demands of 17 Gb/s Fiber Channel serial and 100 Gb/s (4x25 Gb/s or 5x20 Gb/s) parallel applications in local and storage area networks. This paper covers 10 Gb/s GenX production distributions and improved GenX VCSEL device design to meet low-power requirements at 20 Gb/s. We have successfully demonstrated low threshold current of 0.65 mA at 25°C using nominal 7.3 μm oxide-aperture GenX VCSELs. They can be directly modulated up to 25 Gb/s with open eyes at 6 mA bias. With the same design, open eyes of 20 Gb/s is achieved at bias current as low as 4 mA (9 KA/cm2) at 25°C and 8 mA (18 KA/cm2) at 70°C. These operation conditions are comparable to current 10 Gb/s GenX VCSELs in production which have been shown a great field history.

Optimizing 10Gbps VCSEL for real-world laser driver in parallel optical transceiver

Recent VCSEL drivers for high data rate parallel transceivers are designed to DC couple to the VCSELs. These drivers normally include no back termination to save power. Due to mechanical restrictions, the wire bond between the drivers output and the laser is usually quite long. Such laser drivers in a transceiver can cause excessive optical eye distortions (overshoot, pattern dependent jitter, etc.) to a VCSEL which performs well when driven by a 50Ohm source. Therefore more careful design optimizations (of the VCSELs intrinsic laser behavior and its parasitic elements) are needed for such applications. In most cases, this is the only way to achieve good transceiver performance for a given VCSEL driver IC. In this talk, we present Emcores recent effort to optimize the 850nm 10G VCSEL array for the real world laser drivers used in parallel transceivers and active cables.

Emcore VCSEL Failure Mechanism and Resolution

Extensive VCSEL reliability enhancements have been carried out at Emcore in the past year with significant results. In this talk, we will present the failure mechanisms, the method and effectiveness of wafer and die screening, and the approaches to eliminate these failure mechanisms. Results of improved reliability will also be discussed.

The next generation high data rate VCSEL development at SEDU

In May of 2012, Emcore’s VCSEL FAB and VCSEL based transceiver business joined Sumitomo Electric Device Innovations USA (SEDU). After this change of ownership, our high speed VCSEL development effort continues. In this paper, we will report the progress we made in the past year in our 25Gbps to 28Gbps VCSEL. This next generation device is targeted for EDR, 32GFC as well as other optical interconnect applications.

Progress towards commercialization of 25-Gb/s VCSELs

In this paper, we will present the development progress of 850-nm VCSELs operating at 25 Gbit/s and beyond at Sumitomo Electric Device Innovations USA. With improved growth of indium-containing quantum wells, we have demonstrated low-power-consumption VCSELs that can operate at 25 – 28 Gbit/s with reduced current density and enhanced reliability. We will also present recent progress on the improved performance of the new device in EDR cables.