Analytical boron diffusivity model in silicon for thermal diffusion from boron silicate glass film

Abstract

An analytical boron diffusivity model in silicon for thermal diffusion from a boron silicate glass (BSG) film has been proposed in terms of enhanced diffusion due to boron-silicon interstitial pair formation. The silicon interstitial generation is considered to be a result of the silicon kick-out mechanism by the diffused boron at the surface. The additional silicon interstitial generation in the bulk silicon is considered to be the dissociation of the diffused pairs. The former one causes the surface boron concentration dependent diffusion. The latter one causes the local boron concentration dependent diffusion. The calculated boron profiles based on the diffusivity model are confirmed to agree with the actual diffusion profiles measured by secondary ion mass spectroscopy (SIMS) for a wide range of the BSG boron concentration. This analytical diffusivity model is a helpful tool for p+ boron diffusion process optimization of n-type solar cell manufacturing.

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and functional materials

“…The age of individual uranium-plutonium particles with varying U/Pu ratios (1-70) were determined using ICP-MS. 167 The micron-sized particles were prepared from U and Pu certi-ed materials where the Pu material was known to have last been puried on July 14 th 2008. The authors determined the purication age experimentally using 241 Am/ 241 Pu using high resolution ICP-MS equipped with a desolvation system to ensure that hydride-based interferences were minimised. Aer dissolution of the particles, picogram to femtogram levels of Am, Pu and U were separated using a small anion exchange column.…”

“…Aer dissolution of the particles, picogram to femtogram levels of Am, Pu and U were separated using a small anion exchange column. The 241 Am/ 241 Pu were determined accurately by spiking pure 243 Am into the sample solution. The experimentally derived ages were in good agreement with the expected age, with the difference being only 0.27 years.…”

“…185 The effect of the heating rate of the evaporation lament on the analysis of Pu ranging from 0.1-1000 fg was tested, with results indicating that effects were minimal over the range 100-250 mA min À1 . Assorted isotope ratios ( 238 Pu/ 239 Pu, 240 Pu/ 239 Pu, 241 Pu/ 239 Pu and 242 Pu/ 239 Pu) were measured in as little as 70 fg of SRM 947. The 240 Pu/ 239 Pu could be determined in 0.1 fg, which corresponds to a plutonium oxide particle size of 0.2 mm.…”

“…The 239 Pu could be detected with a sample amount of 0.03 fg, corresponding to a LOD of 0.006 fg. The differences in evaporation temperatures between 238 Pu and 238 U as well as 241 Am and 241 Pu enabled a clear distinction between them, meaning that a chemical separation was not necessary.…”

Investigation of Boron Thermal Diffusion from Atmospheric Pressure Chemical Vapor Deposited Boron Silicate Glass for N-Type Solar Cell Process Application

“…Because BRL consists of silicon borides, the crystal structure changes. Thus, BRL existence on the surface affects boron diffusion as described in [17]. To manipulate and predict the boron diffusion profile, a simulator to calculate the boron profile after the diffusion is indispensable because the diffusion mechanism is quite complicated [18,19].…”