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We exploit one of the largest data leaks, to date, to study whether and how firms use secret offshore vehicles. From the leaked data, we identify 338 listed firms as users of secret offshore vehicles and document that these vehicles are used to finance corruption, avoid taxes, and expropriate shareholders. Overall, the leak erased $\$$ 174 billion in market capitalization among implicated firms. Following the increased transparency brought about by the leak, implicated firms experience lower sales from perceptively corrupt countries and avoid less tax. We conservatively estimate that 1 in 7 firms have offshore secrets. Received May 29, 2017; editorial decision December 2, 2018 by Editor Itay Goldstein. Authors have furnished an Internet Appendix, which is available on the Oxford University Press Web site next to the link to the final published paper online. [ABSTRACT FROM AUTHOR]

We conjecture that board renewal mechanisms—those substantive enough to renew the thinking of the board—are required before investors can address the mismatch between their preferences regarding environmental sustainability and what insiders at firms are actually doing. We identify the adoption of majority voting for directors and the introduction of a female director as two corporate governance mechanisms potentially strong enough to renew a board's thinking on sustainability. Using a sample of 3,293 firms from 41 countries, along with quasi‐exogenous shocks to board renewal mechanisms in Canada and France, we find that both board renewal mechanisms are associated with significantly higher future environmental performance. Further tests provide suggestive evidence that board renewal is more strongly associated with environmental performance in settings with better institutions and more motivated institutional investors. These results suggest the importance of board renewal for alignment of firm policies with investor preferences around the world. [ABSTRACT FROM AUTHOR]

The phosphosilicate glass (PSG), fabricated by tube furnace diffusion using a POCl3 source, is widely used as a dopant source in the manufacturing of crystalline silicon solar cells. Although it has been a widely addressed research topic for a long time, there is still lack of a comprehensive understanding of aspects such as the growth, the chemical composition, possible phosphorus depletion, the resulting in-diffused phosphorus profiles, the gettering behavior in silicon, and finally the metal-contact formation. This paper addresses these different aspects simultaneously to further optimize process conditions for photovoltaic applications. To do so, a wide range of experimental data is used and combined with device and process simulations, leading to a more comprehensive interpretation. The results show that slight changes in the PSG process conditions can produce high-quality emitters. It is predicted that PSG processes at 860 °C for 60 min in combination with an etch-back and laser doping from PSG layer results in high-quality emitters with a peak dopant density Npeak=8.0×1018cm-3 and a junction depth dj=0.4 μm, resulting in a sheet resistivity ρsh=380 Ω/sq and a saturation current-density J0 below 10 fA/cm2. With these properties, the POCl3 process can compete with ion implantation or doped oxide approaches. [ABSTRACT FROM AUTHOR]

The performance of passivated emitter and rear (PERC) solar cells made of p-type Si wafers is often limited by recombination in the phosphorus-doped emitter. To overcome this limitation, a realistic PERC solar cell is simulated, whereby the conventional phosphorus-doped emitter is replaced by a thin, crystalline gallium phosphide (GaP) layer. The resulting GaP/Si PERC cell is compared to Si PERC cells, which have (i) a standard POCl3 diffused emitter, (ii) a solid-state diffused emitter, or (iii) a high efficiency ion-implanted emitter. The maximum efficiencies for these realistic PERC cells are between 20.5% and 21.2% for the phosphorus-doped emitters (i)-(iii), and up to 21.6% for the GaP emitter. The major advantage of this GaP hetero-emitter is a significantly reduced recombination loss, resulting in a higher Voc. This is so because the high valence band offset between GaP and Si acts as a nearly ideal minority carrier blocker. This effect is comparable to amorphous Si. However, the GaP layer can be contacted with metal fingers like crystalline Si, so no conductive oxide is necessary. Compared to the conventional PERC structure, the GaP/Si PERC cell requires a lower Si base doping density, which reduces the impact of the boron-oxygen complexes. Despite the lower base doping, fewer rear local contacts are necessary. This is so because the GaP emitter shows reduced recombination, leading to a higher minority electron density in the base and, in turn, to a higher base conductivity. [ABSTRACT FROM AUTHOR]

Effective control of the dose of diffused phosphorus emitter profiles is crucial for optimization of crystalline silicon solar cells, but it requires detailed understanding of the POCl3 doping process. We measure concentration profiles within the deposited phosphosilicate glass (PSG) layer for a range of POCl3 doping conditions and find that (i) its composition is nearly independent of process conditions and (ii) it is separated from Si by a thin SiO2 layer. We also find strong accumulation of P at the SiO2-Si interface. As common linear-parabolic models cannot fully explain the observed kinetics of PSG thickness and phosphorus dose in Si, we present an improved model including oxygen depletion and dose saturation, giving a better explanation of the experimental data. In contrast to previous models that adjust the peak phosphorus concentration at the Si surface to match the measured profiles, our models accurately predict the time-dependent dose behavior under different experimental conditions. We further couple this growth model with previously reported phosphorus diffusion and deactivation models in silicon, providing full modeling of the POCl3 doping process. [ABSTRACT FROM AUTHOR]