Determination of aluminum diffusion parameters in silicon

Abstract

Aluminum as the fastest diffusing acceptor dopant in silicon is commonly used for the fabrication of power semiconductors with p-n junction depths ranging from some microns to more than hundred microns. Although used since long, its diffusion behavior was not sufficiently characterized to support computer-aided design of new devices. In this work, the intrinsic diffusion of aluminum was investigated in the temperature range from 850 to 1290°C. Combining nitridation and oxidation experiments, the fractional diffusivity via self-interstitials was determined. By diffusion in high-concentration boron- and phosphorus-doped silicon the behavior of aluminum under extrisic conditions was investigated

Rapid Thermal Annealing and Hydrogen Passivation of Polycrystalline Silicon Thin-Film Solar Cells on Low-Temperature Glass

“…A schematic representation of this effect is shown in Figure 13 where there is enhanced diffusion along the grain boundary in region "B" in contrast to normal diffusion in region "A." Al is the fastest diffuser of the typical dopants in Si [15,20] and especially in the open structure of grain boundaries in pc-Si [16]. The depth of enhanced diffusion down grain boundaries compared to intragrain diffusion has been shown to be inversely dependent upon temperature, that is, a hotter RTA process results in a shallower diffusion depth in the grain boundary [21,22].…”

Structure and chemistry of aluminum predose layers in AlN epitaxy on (111) silicon

“…Both have been measured [22,23]. Using these values, the calculated diffusion lengths for a 10 s deposition are 25 nm and 540 mm for aluminum in silicon and silicon in aluminum, respec-…”

Electron beam induced current microscopy investigation of GaN nanowire arrays grown on Si substrates

“…The small size of the Al atom leads to a rather high diffusion coefficient. Several micron penetration of Al into Si can be achieved for long annealing durations [36]. This Al diffusion induces a p-doping of the Si layer close to the surface and creates a p-n junction in the Si wafer [38], similar to the process used in Si solar cell manufacturing.…”

“…It is likely that this procedure induces the diffusion of Al deep into the Si wafer. Al diffusion in Si has been investigated in the literature [36,37]. The small size of the Al atom leads to a rather high diffusion coefficient.…”