Abstract-In recent years, high-performance multicrystalline silicon (HPMC-Si) has emerged as an attractive alternative to traditional ingot-based multicrystalline silicon (mc-Si), with a similar cost structure but improved cell performance. Herein, we evaluate the gettering response of traditional mc-Si and HPMC-Si. Microanalytical techniques demonstrate that HPMC-Si and mc-Si share similar lifetime-limiting defect types but have different relative concentrations and distributions. HPMC-Si shows a substantial lifetime improvement after P-gettering compared with mc-Si, chiefly because of lower area fraction of dislocation-rich clusters. In both materials, the dislocation clusters and grain boundaries were associated with relatively higher interstitial iron point-defect concentrations after diffusion, which is suggestive of dissolving metal-impurity precipitates. The relatively fewer dislocation clusters in HPMC-Si are shown to exhibit similar characteristics to those found in mc-Si. Given similar governing principles, a proxy to determine relative recombination activity of dislocation clusters developed for mc-Si is successfully transferred to HPMC-Si. The lifetime in the remainder of HPMC-Si material is found to be limited by grain-boundary recombination. To reduce the recombination activity of grain boundaries in HPMC-Si, coordinated impurity control during growth, gettering, and passivation must be developed.
Optimizing materials properties for a given structural application can be obtained either by selecting the proper bulk material with appropriate properties, or playing with the degrees of freedom provided by the geometry. [1] The geometry may be the one of the component (an I beam being more efficient that a square one for instance) or it can be an "internal geometry of the material itself. [2] Interlocked structure is a strategy to design "prefragmented materials", taking advantage of topological constraints between elementary blocks of prescribed geometry, in order to provide new materials with properties which are, for bulk materials, antagonistic, such as high strength and good damage tolerance. As an example, the recent work from Dyskin et al. 2003 [3,4] shows that an assembly of blocks of osteomorph shapes is an interesting solution to limit crack propagation in brittle materials.Topological interlocking is a promising route to develop "hybrid materials" with new properties. The variety of possible shapes for the elementary block makes a systematic investigation impossible. It is therefore necessary to develop the material from modelling, and to test rapidly and in a cheap manner the proposed geometries. Ice block is a good model material to test possible geometries. In addition, it has the property of providing an easy way of changing the friction coefficients between blocks, simply by changing the testing temperature. The present paper explores, for a given osteomorphic geometry, the influence of the friction coefficient on the indentation behaviour of an interlocked material
Ice Friction Coefficient
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.