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This paper introduces a novel method for the three-dimensional characterization of flyers based on microscopic photonic Doppler velocimetry (PDV) velocity field measurements. By strategically positioning 56 PDV velocity measurement spots within a circle of 0.50 mm diameter at an interval of approximately 58 μm, we achieve spatially resolved measurements of the velocity history of the flyer during its flight within the barrel and subsequent impact on a transparent window. Crucial data, such as displacement history, impact time, and impact pulse duration, can be extracted at each measurement spot. Furthermore, a correlation analysis of these datasets enables the reconstruction of the flyer's three-dimensional morphology, both during its flight inside the barrel and at the critical moment of impact with the window. This method offers a remarkable temporal resolution in the order of nanoseconds and a spatial resolution in the order of micrometers. With the characteristics of high spatial resolution and high experimental efficiency, the microscope PDV technology is poised to become an essential research tool in the study of action mechanisms, design optimization, and determination of initiation criteria for exploding foil initiators. [ABSTRACT FROM AUTHOR]

We have conducted a systematic simulation study on light absorption in a silicon nanohole structure that has randomness introduced into its structural parameters, which include the hole radius, depth, and position. It is found that light absorption is enhanced for the random structures compared to their periodic counterparts. This is attributed to additional resonances induced by the structural disorders, broadening of the existing resonance, and lower optical reflection. The highest light absorption is obtained for the structure with randomness in hole position, which achieves a 12.7% enhancement compared with the periodic structure. VC [ABSTRACT FROM AUTHOR]

We propose a hybrid nanostructure that comprises nanopyramids and nanoholes for thin film silicon (Si) solar cells. The hybrid structure demonstrates a stronger light trapping ability that is beyond the Lambertian limit. This is achieved with the smaller dimension nanohole structure which effectively reduces shorter wavelength light reflection, and the larger dimension nanopyramid structure which significantly enhances longer wavelength light trapping. An ultimate efficiency of 38.3% is yielded for a 2 lm thick Si cell incorporated with the hybrid structure, which is higher than that achievable corresponding to the Lambertian limit. Moreover, the high ultimate efficiency is retained as the incident angle increases from normal incidence to 50° for TM polarized sunlight. Therefore, the proposed hybrid structure is very promising to enhance the performance of thin film Si solar cells. [ABSTRACT FROM AUTHOR]

The effects of chemical compositions, hot deformation parameters, thermal treatment and microstructures on the formation of [006] texture in PrFeBCu system are studied in order to understand the mechanism for obtaining [006] texture. The results indicate that for hot-deformed PrFeBCu system, 1173 K is the critical temperature of the equal strength among Pr2G2(sub 14)B and the residual grain-boundary phase and also the domains observed on different sections are given.

The reflectance and absorption characteristics of slanting silicon nanowires (SiNWs) structure have been simulated using finite element method to provide a design guideline for its application in solar cell. The slanting angle for the nanowire structure is set at 40° on Si (111) wafer. The impact of the structural periodicity (P) and wire diameter/periodicity (D/P) ratio on the optical characteristics of the slanting SiNW has been systematically analyzed. It has been found that due to the much suppressed light reflection and stronger light trapping ability, the light absorption is significantly enhanced for the slanting SiNW structure compared with vertical SiNW structure. The optimal absorption condition is achieved when P = 800 nm and D/P = 0.7, yielding the highest ultimate efficiency of 33.45%. The result is better than the 28.36% that can be achieved for optimum vertical SiNWs. A comparison of the absorption characteristics of optimum slanting and vertical SiNWs structures is presented and analyzed in terms of the physical light interaction with the structures. [ABSTRACT FROM AUTHOR]

In this paper, a systematic design and analysis of gallium arsenide thin film solar cells incorporated with a periodic silver nanoparticles (NPs) structure to enhance light absorption is presented using the finite element method. The influence of the silver nanoparticles diameter and structure periodicity on light absorption has been examined. It is found that the absorption is significantly enhanced due to the surface plasmon induced by the silver nanoparticles. The optimal structural parameters are achieved when the diameter of the nanoparticles is 200 nm and the periodicity is 444 nm. This gives rise to a maximum ultimate photocurrent of 26.32 mA/cm2 under AM1.5G solar irradiation. In addition, the underlying physics that accounts for the enhancement is discussed. [ABSTRACT FROM AUTHOR]

The DPSS Nd:YVO4 UV laser is used to anneal amorphous silicon (a-Si) film to achieve crystallization and nano-dome surface texturing simultaneously in a one-step annealing process. With pulse energy of 380 mJ/cm2 and repetition rate of 20 kHz, the a-Si can be crystallized by the sequential lateral solidification process, which is evidenced by both SEM characterization and Raman spectra. In addition, the nano-dome like structure is confirmed by AFM characterization, which can lead to ∼200% boost in terms of light absorption as measured by UV-Visible - Near-infrared scanning spectrophotometer. This study highlights the great potential of Nd:YVO4 UV laser for its application in thin film Si solar cell industry to improve the film quality and light trapping capability. [ABSTRACT FROM AUTHOR]

We investigate the tuning of Schottky barrier height (SBH) of nickel silicide formed by pulsed excimer laser anneal of nickel on silicon implanted with aluminum (Al). A wide range of laser fluence was investigated, and it has been found that laser fluence influences the distribution of Al within the silicide and at the silicide/silicon interface. This in turn affects the effective whole SBH ([uppercase_phi_synonym]Bp) at the silicide/silicon junction. High Al concentration at the silicide/silicon interface and high temperature for nano-second duration to achieve Al activation while keeping the Al concentration within the silicide low is vital for achieving low [uppercase_phi_synonym]Bp. We demonstrate the achievement of one of the lowest reported [uppercase_phi_synonym]Bp of ∼0.11 eV. This introduces a new option for forming nickel silicide contacts with reduced contact resistance at low thermal budget for possible adoption in future metal-oxide-semiconductor transistor technologies. [ABSTRACT FROM AUTHOR]

Silicon thin film with a nanohole (NH) array textured surface is systematically studied via simulation for solar energy harvesting and compared with a nanopillar (NP) array textured one. It is found that for the same thickness and optimized structure parameters, the NH array shows superior light trapping capability and thus, higher power conversion efficiency than its NP counterpart. The requirement for efficient cells at the optically optimized NH and NP geometries are studied in terms of minority carrier diffusion length, emitter doping level, and the emitter junction depth after considering the impact of surface recombination velocity. The results provide a practical guideline to design and fabricate high efficiency and cost effective NH textured Si thin film solar cells. [ABSTRACT FROM AUTHOR]

The supersaturated and metastable boron produced by laser anneal could deactivate during post-laser-thermal-cycles and lead to undesirable performance degradation. The effect of tin incorporation on the thermal stability of boron was studied for the first time and suppressed boron deactivation during post-laser-rapid-thermal-anneal was observed with tin coimplantation. High resolution x-ray diffraction measurement indicates that the tensile strain caused by a high boron concentration was reduced by the introduction of tin, which effectively reduces the strain energy and therefore, enhances the thermal stability of boron in post-laser-anneal rapid thermal processing. [ABSTRACT FROM AUTHOR]

The application of laser annealing for the production of different metal nanoparticles as catalysts in the production of large scale Si nanohole array is analyzed. Nanohole texturing is shown to be extremely beneficial for the suppression of the optical characteristics of the systems.

In this paper, laser annealing is used to produce metal (Ag) nanoparticles as etching catalyst on a silicon surface, which enables controllable fabrication of large-scale nanohole array surface texturing without using a mask. Semispherical Ag nanoparticles with variable size and distribution are achievable by manipulating the laser annealing parameters and metal film thickness, and the underlying physics is clarified. The nanoholes array in silicon can then be realized by selective etching of silicon under Ag pattern. The optical characteristics suggest that the surface reflection can be significantly suppressed owing to the nanohole texturing, which is promising for thin film photovoltaic applications. [ABSTRACT FROM AUTHOR]

In order to research the formation mechanism of [006] texture of cast/hot-pressed magnets, effects of compositions, hot deformation parameters, and thermal annealing on [006] texture and microstructures of hot-pressed magnets of Pr[SUBx]Fe[SUB93.5-x]B[SUB5]Cu[SUB1.5] (x = 15 - 19) have been studied under the conditions of hot-pressing temperature T = 973- 1273 K, strain rate V = 10[SUP-6]- 10[SUP0]/S, and strain E = 0% - 80%. Higher praseodymium content is detrimental to the formation of the ideal texture [006]. Only at a hot-pressing temperature of 973-1123 K and without fractures during the hot deformation, can [006] texture of Pr[SUBx]Fe[SUB93.5-x]B[SUB5]Cu[SUB1.5] be obtained. Below the critical temperature of the equal strength among Pr[SUB2]Fe[SUB14]B and the residual grain-boundary phases, 1173 K, the boundary phases have a higher strength than that of Pr[SUB2]Fe[SUB14]B, and most of deformation can be focused within Pr[SUB2]Fe[SUB14]B grains and after thermal annealing at 1123 K for 8 h, I[SUB006] become more distinguished. The B[SUBr] of these magnets reach 1320 mT and their magnetic domains, on the longitudinal section, are platelike, with domain walls parallel to the hot deformation direction. The domains on the transverse section are mazelike. [ABSTRACT FROM AUTHOR]