For nearly twenty years most models of VCSEL wearout reliability have incorporated Arrhenius activation energy near
0.7 eV, usually with a modest current exponent in addition. As VCSEL production extends into more wavelength, power, and speed regimes new active regions, mirror designs, and growth conditions have become necessary. Even at
more traditional VCSEL 850-nm wavelengths instances of very different reliability acceleration factors have arisen. In
some cases these have profound effects on the expected reliability under normal use conditions, resulting in wearout
lifetimes that can vary more than an order of magnitude. These differences enable the extension of VCSELs in
communications applications to even greater speeds with reliability equal to or even greater than the previous lowerspeed devices. This paper discusses some of the new applications, different wearout behaviors, and their implications in real-life operation. The effect of different acceleration behaviors on reliability testing is also addressed.
Commercial demand for optical transceivers operating at 14Gbps is now a reality. It is further expected that
communications standards utilizing 850nm VCSELs at speeds up to 28Gbps will be ratified in the near future. We report
on the development and productization of 850nm VCSELs for several applications, including high speed (both 14Gbps
and 28Gbps) operation to support the continued fulfillment of data communication demand.
VCSELs continue to be widely deployed in data communication networks. The total bandwidth requirements continue to
grow, resulting in higher data rates and utilization of both spatial and wavelength multiplexing. This paper will discuss
recent results on VCSELs operating at aggregate speeds up to 1000Gbps as well as the prospects and results on
extending to higher serial data rates.
In this paper we will discuss recent results on high speed VCSELs targeted for the emerging 16GFC (Fibre Channel)
standard as well as the now forming 25Gbps PCI express standard. Significant challenges in designing for reliability and
speed have been overcome to demonstrate VCSELs with bandwidth in excess of 20Gbps.
In this paper we describe progress in moving VCSELs toward production-ready status in several applications, among
others including substantially higher modulation speeds (14-25 Gbps, or even higher) than in current production. In
addition we describe potential VCSEL failure mechanisms not previously published, as well as the limitations of some
reliability testing techniques.
During a year of substantial consolidation in the VCSEL industry, Honeywell sold their VCSEL Optical Products Division, which has now officially changed its name to Advanced Optical Components (AOC). Both manufacture and applied research continue, however. Some of the developments of the past year are discussed in this paper. They include advances in the understanding of VCSEL degradation physics, substantial improvements in long-wavelength VCSEL performance, and continuing progress in manufacturing technology. In addition, higher speed serial communications products, at 10 gigabits and particularly at 4 gigabits per second, have shown faster than predicted growth. We place these technologies and AOC's approach to them in a market perspective, along with other emerging applications.
In this paper we describe both the 1310 and 1550 nm VCSEL development work at Honeywell using both InP and GaAs substrates, and using both MOCVD and MBE. We describe the material systems, the designs, the growth techniques, and the promising results obtained and compare them to the needs of the communications industry. InGaAsN quantum well based VCSELs have been demonstrated to 1338 nm lasing at temperatures up to 90 C. Continuous wave InP based 1550 nm VCSELs have also been demonstrated.
Born of necessity of application, the Vertical Cavity Surface Emitting Laser (VCSEL) is now found in nearly all optical networking systems based on standards such as the IEEE 802.3z and ANSI X3.t11. Reliability continues to be the hallmark of the technology, and the volume manufacturing aspects are now realized. While VCSEls satisfying optical networking standards continue to provide the highest volume applications, the advantages of the technology are beginning to enable novel optical equipment. This paper explores development of VCSELs at wavelengths from 650 to 850nm, and the commercial applications of these devices in both the data communications and optical sensing arenas. VCSELs operating at longer wavelengths are also being developed, but are not at a stage of commercialization to be discussed in this forum.
Each year, more VCSEL technologies make the transition from research curiosities to commercially available products. In this paper we describe several such technologies at Honeywell, each at a different stage of that transition. Oxide-confined devices are already past the transition stage. We describe the generally excellent reliability of oxide-confined devices already in high-volume production, and compare it to results of the most recent-and possibly last-long-term reliability study of proton-implanted VCSELs. We report on detailed package-VCSEL interaction modeling, which is being used to improve performance and extend the life of common form-factor packages. We also note Honeywell's progress toward commercialization of VCSELs and allied products at wavelengths other than 850 nm.
In 1996, Honeywell was the first company to commercialize VCSEL technology, and today it is the world's largest VCSEL component supplier. This paper will focus on the aspects of VCSEL manufacture that are important to maintain highly reliable and producible components. For current VCSEL products, we will address the evolution of VCSEL reliability and its effect on performance in data communications systems. New applications in both the data communications and sensor markets are being enabled by the VCSEL technology. This paper will also discuss new VCSEL structures, packages and wavelengths that are being commercialized by Honeywell to address these emerging markets.
Proc. SPIE. 3004, Fabrication, Testing, and Reliability of Semiconductor Lasers II
KEYWORDS: Signal to noise ratio, Modulation, Polarization, Signal attenuation, Resistance, Polarizers, Vertical cavity surface emitting lasers, Circuit switching, Charged particle optics, Near field optics
The high speed characteristics of Vertical Cavity Surface Emitting Lasers (VCSELs) for use in modern high bandwidth fiber optical networks is presented. An equivalent circuit model based on microwave network analyzer S11 measurements is developed. The dynamic operation of multi- transverse mode VCSELs is also investigated. Experimentally, a laser with two orthogonally polarized modes is examined. We show that each of the transverse laser modes may have significantly different rise and fall times. A multimode rate equation model is used to predict the exact pulseshape for each mode. The laser gain is saturated by the total optical intensity, and the sum of the modal powers is shown to have a constant rise and fall time. The system performance in terms of the bit error rate is also investigated. We demonstrate that selective attenuation of the optical modes can lead to an increase in the bit error rate due to polarization partitioning noise.