MKS Instruments (Japan)

Tunnel oxide passivated contact (TOPCon) solar cells will likely become the most produced crystalline silicon photovoltaic architecture within the next five years. The technology relies on multiple thin films to improve cell efficiency by further reducing electron-hole recombination at metal-semiconductor interfaces. Lasers are used to remove the anti-reflection thin film layer to prepare regions of the cells for electrical contact formation (“metallization”). This process—laser contact opening or LCO—is challenging in that the underlying thin films must suffer minimal damage. TOPCon is an ideal architecture for implementing electrochemical plating metallization, which has certain advantages over conventional methods. In this work we report on the use of ultraviolet (UV) wavelength ultrashort pulse lasers for TOPCon LCO processing in concert with electrochemical plating metallization. Laser parameters selection is reviewed, and processing results are analyzed with optical and scanning electron microscopy. Complete solar cells are fabricated and performance metrics are discussed.

Bu mqald ingilis dilind ara cmllrin intonasiya xsusiyytlri v onlarn ifad etdiyi mnalar zrind dayanlr.Ara cmllr, yni sas cmldn knar olan v onun mnasn tamamlayan ifadlr, dilin nsiyyt qabiliyytind mhm rol oynayr.Aradrma rivsind intonasiyann, xsusil vuru, ton, v ritm elementlrinin ara cmllrin aydnln, duyusal tsirini v kommunikativ effektini nec dyidirdiyi mqayisli olaraq thlil edilir.Eyni zamanda,

Abstract A detailled study of the impact of stereoelectronic effects of olefins in the Matsuda‐Heck‐reaction was addressed by kinetic studies. In addition to the stereoelectronic effects of the olefins used, their influence on the formation of the catalytic Pd colloids was also investigated. Depending on the olefin used, different particle size distributions were obtained on the one hand and, on the other hand, inhibition effects due to adsorption of the olefins on the Pd colloids were observed. Based on these findings, it was possible to optimize reaction conditions for the respective olefins. The presented kinetic data were supplemented by STEM‐measurements.

The authors report on processing silicon with bursts of hundreds of subpicosecond pulses with an intraburst pulse repetition frequency of 0.86 GHz at 515 nm. They find that the burst-to-burst overlap is a key parameter in optimizing the ablation efficiency for the line scribing and milling processes, contrary to traditional nonburst ultrafast processes. A nanosecond laser reference experiment and the corresponding multiphase simulations demonstrate that this behavior is directly related to the hydrodynamic effects of the molten material generated during the laser processing. Exploring the hole and scribe morphology with scanning transmission electron microscopy and selective area electron diffraction yields a surprise: holes show no sign of a polycrystalline or amorphous heat affected zone, while scribed lines clearly do. The multiphase modeling provides a likely explanation—it is not “ablation cooling.”

The authors report on processing silicon with bursts of hundreds of subpicosecond pulses with an intraburst pulse repetition frequency of 0.86 GHz at 515 nm. They find that the burst-to-burst overlap is a key parameter in optimizing the ablation efficiency for the line scribing and milling processes, contrary to traditional nonburst ultrafast processes. A nanosecond laser reference experiment and the corresponding multiphase simulations demonstrate that this behavior is directly related to the hydrodynamic effects of the molten material generated during the laser processing. Exploring the hole and scribe morphology with scanning transmission electron microscopy and selective area electron diffraction yields a surprise: holes show no sign of a polycrystalline or amorphous heat affected zone, while scribed lines clearly do. The multiphase modeling provides a likely explanation—it is not “ablation cooling.”

The Yes-associated protein (YAP) is a major oncoprotein responsible for cell proliferation control. YAP's oncogenic activity is regulated by both the Hippo kinase cascade and uniquely by a mechanical-force-induced actin remodeling process. Inspired by reports that ovarian cancer cells specifically accumulate the phosphatase protein ALPP on lipid rafts that physically link to actin cytoskeleton, we developed a molecular self-assembly (MSA) technology that selectively halts cancer cell proliferation by inactivating YAP. We designed a ruthenium-complex-peptide precursor molecule that, upon cleavage of phosphate groups, undergoes self-assembly to form nanostructures specifically on lipid rafts of ovarian cancer cells. The MSAs exert potent, cancer-cell-specific antiproliferative effects in multiple cancer cell lines and in mouse xenograft tumor models. Our work illustrates how basic biochemical insights can be exploited as the basis for a nanobiointerface fabrication technology which links nanoscale protein activities at specific subcellular locations to molecular biological activities to suppress cancer cell proliferation.

Abstract Workpieces that are lightweight, easy building of complicated structures, fast production cycles – the advantages of additive manufacturing are many and appealing. But what started out as an approach for rapid prototyping will soon be used even to produce critical parts for airplanes or space shuttles. As the number of applications grows, so do the technological requirements. This is why it is so important for the parameters of the laser beam always to be reproducible – and not only on one machine over time, but also from one machine to the next.

Rebaudioside A is a natural noncaloric high-potency sweetener extracted from the leaves of Stevia rebaudiana. With rebaudioside A use increasing in foods, understanding the factors affecting its stability is necessary. This project evaluated the degradation rate constants of rebaudioside A in water, 0.1 M phosphate buffer, and 0.1 M citrate buffer at pH 3 and 7 as a function of ultraviolet (UV) light intensity (365 nm, 0 μW/cm2 for dark conditions, 27 μW/cm2 for low intensity, and 190 μW/cm2 for high intensity) at 32.5 °C. Rebaudioside A stability was adversely affected by light exposure. The pseudo-1st-order degradation rate constants increased significantly (P < 0.05) with increasing light intensity in all solutions. Under dark conditions, rebaudioside A in phosphate buffers was more susceptible to breakdown than in water and citrate buffers at both pH levels. However, exposure to UV light resulted in rebaudioside A degradation occurring approximately 10 times faster in citrate than in phosphate buffers at both pH levels. The sensitivity of rebaudioside A to UV light was greater in citrate buffers than in water or phosphate buffers. The use of light-protective packaging for beverages containing rebaudioside A will improve its stability.

Vibration damping of honeycomb optical tables had been subject of significant research and development efforts during several decades. These efforts resulted in tuned and broadband damping treatments, as well as active damping systems that found extensive practical applications. Smaller optical platforms (breadboards) are often used for vibration-sensitive applications due to dearth of laboratory space and increased sensitivity of small optical instruments. Relatively massive damping devices that work for large tables are not applicable to smaller (usually up to about 10 cm thick) breadboards. This paper describes a new method for damping resonance vibration of optical breadboards with honeycomb cores. The method makes use of modal geometry of orthotropic laminated plates by integrating a layer of highly damped material between two surfaces making it to work in shear. Physical principle, optimization procedure, practical designs, implementation and test results of damped breadboards are presented.