A dimensionless solution is presented for the surface recombination component τs of the effective lifetime τeff of the fundamental mode of excess carrier decay in semiconductors. The case of different surface recombination velocities S1 and S2 is analyzed. As the problem is solved in terms of dimensionless variables, the solution obtained is a general one. A normalized surface lifetime τ *s is plotted as a function of normalized surface recombination velocities S*1 and S*2. This allows rapid calculation and visualization of the influence of surface recombination on τs, for all possible cases of recombination parameters. That is, for any value of S1, S2, W (the width of a sample), and D (the diffusion constant) a solution for the surface lifetime τs can be found from the one graphical solution. It is a useful tool for rapidly interpreting the effect of surface recombination in transient lifetime measurement experiments. For the cases where S=S1=S2, or where S1 or S2 is zero, this approach is an elegant tool for investigating useful approximations for τs.

The achievement of high-quality continuous polycrystalline silicon (poly-Si) layers onto glass substrates by using aluminum-induced crystallization is reported. The crystallization behavior of dc sputtered amorphous silicon on glass induced by an Al interface layer has been investigated above and below the eutectic temperature of 577 °C. Secondary electron micrographs in combination with energy-dispersive x-ray microanalysis show that annealing below this temperature leads to the juxtaposed Al and Si layers exchanging places. The newly formed poly-Si layer is fully crystallized and of good crystalline quality, according to Raman spectroscopy and transmission electron microscopy investigations. At 500 °C, the time needed to crystallize a 500-nm-thick Si layer is as short as 30 min. By annealing above the eutectic temperatures, layer exchange is not as pronounced and the newly formed Al layer is found to contain a network of crystallized Si.

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A recent review has suggested that the commonly cited value of 1.45×1010 cm−3 for the silicon intrinsic carrier concentration at 300 K is inconsistent with the best experimental data. An alternate value of 1.08×1010 cm−3 was proposed. From measurements of the current-voltage characteristics of p-n junction diodes, this paper reports a new and more accurate determination of this parameter over the 275–375 K temperature range which supports such lower values. The one-standard-deviation uncertainty in the measurement of the intrinsic carrier concentration is estimated to lie in the 3%–4% range, about three times smaller than previous measurements at these temperatures. Additionally, this technique provides information on the minority carrier electron diffusivity in silicon.

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