• Belouet C.

RAD ribbons exhibit a polycrystalline texture similar to that of most melt-grown ribbons with the exception of the WEB material. In this paper, our concern is devoted to a review of defect characterization in as-grown materials as well as after solar cell fabrication. The combination of the EBIC and transmission electron microscopy analyses enabled a detailed investigation of the electrical activity of carbon-silicon interfaces with respect to both their structure and their interaction with grown-in dislocations. The burn-off of the carbon shaper in an oxygen ambient at 1020°C allows the separation of the two polycrystalline sheets from a carbon substrate. Electrical measurements performed after this step showed that bulk properties were improved, whereas EBIC observations indicated an increased activity of dislocation networks. TEM investigations in the conventional and high resolution modes give some answers to questions raised by electrical measurements. Samples, ion-thinned from one side in order to study the defects induced by the diffusion process (POCl3 and 850°C) at the surface, were prepared. A detailed analysis of the dislocation networks completes former studies on similar experiments. In the same way, high resolution results on SiP precipitates are complementary to those obtained by Bourret et al. (1984) on silicon single crystals by sample sectioning.

Recent Publications

May 01, 2020

A Packaged 0.01-26-GHz Single-Chip SiGe Reflectometer for Two-Port Vector Network Analyzers

  • Chung H.
  • Ma Q.
  • Rebeiz G.
  • Sayginer M.

© 1963-2012 IEEE. This article presents a packaged SiGe BiCMOS reflectometer for 0.01-26-GHz two-port vector network analyzers (VNAs). The reflectometer chip is composed of a resistive bridge coupler and two wideband heterodyne receivers for coherent magnitude and phase detection. In addition, a high-linearity receiver channel is designed to accommodate 20 ...

August 01, 2019

Protecting photonic quantum states using topology

  • Blanco-Redondo A.

The use of topology to protect quantum information is well-known to the condensed-matter community and, indeed, topological quantum computing is a bursting field of research and one of the competing avenues to demonstrate that quantum computers can complete certain problems that classical computers cannot. In photonics, however, we are only ...

May 01, 2019

Digital networks at the nexus of productivity growth

  • Kamat S.
  • Prakash S.
  • Saniee I.
  • Weldon M.

This paper takes a fresh look at the debate over the relationship between digital technology and productivity. The argument of economic historian Robert J. Gordon is that digital technology will not lead to increases in productivity such as we saw in the last century, based on his analysis of the ...