The optical properties of type-II GaAsSb/GaAs multiple quantum wells were investigated by photoluminescence. It was found that the peak position of photoluminescence (PL) spectra shows a giant blueshift under a moderate optical excitation level. As the pumping intensity increases further, the saturation of the peak position was observed. The giant blueshift can be interpreted in terms of the band-bending effect due to the spatially photoexcited carriers in a type-II alignment. The saturation effect was attributed to the creation of an energy barrier induced by photocarriers, which prevents the charge transfer. The change of integrated photoluminescence intensity with increasing excitation intensity is also consistent with the band-bending model. In addition, the temperature dependence of the PL spectra reveals that the thermal escape of electrons from the GaAs well into the GaAsSb barrier is responsible for the PL quenching.

During the fabrication of freestanding micromechanical structures, the structures must often be attached to the substrate to prevent movement, particularly during the release process. The attachments are then removed, freeing the structures from the substrate when they are to be used. Tethers are long thin beams that mechanically anchor freestanding structures to the substrate during fabrication, but are easily broken afterwards. This paper focused on fuse-tether designs and the associated technique used to break the tethers, Joule heating. The breaking characteristics of two fuse-tether designs were investigated using different current pulses. For each design, the current pulse that produced the most desirable electrical and mechanical break was chosen for reliability testing. The reliability tests resulted in a 100% success rate. However, molten silicon splattered undesirably in 20% of the cases. In addition to empirical testing, ANSYS R was used to simulate the Joule heating process. The ANSYS R model produced results that closely matched the break characteristics observed in the empirical tests. This research demonstrated that a fuse-tether can be severed reliably with the Joule heating technique, and the fuse-breaking characteristics can be predicted by modeling.

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Finding ways to distribute workloads to each processor core and efficiently reduce power consumption is of vital importance, especially for real-time systems. In this paper, a novel scheduling algorithm is proposed for real-time multicore systems to balance the computation loads and save power. The developed algorithm simultaneously considers multiple criteria, a novel factor, and task deadline, and is called power and deadline-aware multicore scheduling (PDAMS). Experiment results show that the proposed algorithm can greatly reduce energy consumption by up to 54.2% and the deadline times missed, as compared to the other scheduling algorithms outlined in this paper.

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