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Vertical cavity surface emitting lasers (VCSELs) offer advantages of being very cost effective and mass manufacturable. By integrating a VCSEL with a micro-electro-mechanical system (MEMS) cantilever, a tunable VCSEL with wide and continuous wavelength tuning can be obtained. Previous demonstrations of this concept were achieved in the short-wavelength(More)
In this work, the endurance behavior of a ball grid array package is determined at two different temperature cycle conditions: a thermal cycle test and a thermal shock test. The observed failure distributions and failure modes allow deriving a translation factor between the two test conditions. Finite element analyses are carried out to design a predictive(More)
A new method was developed for modeling electronic packages. The method is applied to a BGA 256 on board. The simulation results were compared to measured results of a thermal cycle test and a thermal shock test. The methodology has shown to be accurate and efficient. This work also shows that thermal transient behavior must be considered in situations(More)
This paper presents our effort to predict IC, packaging, and board level reliability problems. Micro-electronic based reliability problems are driven by the mismatch between the different material properties, such as thermal expansion, hygro-swelling, and/or the degradation of interfacial strength. In the past, such reliability problems were treated(More)
We present operating and lifetest data on 795 and 808 nm bars with aluminum-free active regions. Conductively cooled bars operate reliably at CW power outputs of 40 W, and have high efficiency, low beam divergence, and narrow spectra. Record CW powers of 115 W CW are demonstrated at 795 nm for 30% fill-factor bars mounted on microchannel coolers. We also(More)
In this work the results of thermal cycling tests on HVQFN-packages mounted on printed circuit boards are evaluated. The emphasis is on the fatigue life of the soldered interconnections as it is influenced by the printed circuit board, rather than that by the package or the solder. Data from different experimental set-ups are compared: panel thickness and(More)
Usually the mechanical reliability of electronic packages is qualified by temperature cycle tests (TCT). However this is a more or less isothermal test, while in operating condition temperatures can have a non-uniform distribution, because thermal transient effects are present. This effect can play an important role in packages that generate heat, like the(More)
Pulsed as well as cw laser action has been observed in a new host material for Nd(3+) ions, Na(+) beta'' alumina. The unusual characteristics of the material and its known physical properties are briefly described. Absorption spectra, fluorescence lifetime, laser-pulse shape, and peak emission wavelength are presented as experimental evidence, and(More)
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