Platinum and gold diffusion monitor vacancy profiles induced into silicon wafers by aluminum alloying

Abstract

In this paper, we use the gold and platinum marker method, to confirm our preliminary finding that aluminum indiffusion into Si crystal during so‐called “aluminum gettering” (AlG) can result in the injection of vacancies into Si crystal. Depth profiles of Au in p‐type Si have been studied by the DLTS after diffusion at 850 °C for 2 h prior to and subsequent to AlG. The donor concentration attributed to Aus is about two orders of magnitude higher compared with that measured in samples without AlG. Similar results were also observed for Pt. The increase in Pts or Aus concentration in the silicon bulk provides the most direct evidence so far that AlG with 400 nm Al layer, for 50 min at 1100 °C injects vacancies with non‐equilibrium concentrations of about 1015 cm−3. The possible mechanism of vacancies generation is discussed.

Rapid thermal processing induced vacancy-oxygen complexes in Czochralski-grown Si1−xGex

“…For T2 level, the above values are consistent with the previously reported ones for the donor level of Au s [24][25][26]. As for T1 level, it has been previously reported for p-type Au-doped silicon and its DLTS signal is attributed to the non-negligible hole emission from the acceptor level of Au s [18,[27][28][29].…”

“…In this context, while Fourier transformation infrared spectroscopy and deep level transient spectroscopy (DLTS) are often used to characterize the V-O complexes in the electron-irradiated Cz-Si and Cz-Si 1-x Ge x , they cannot be used to directly detect the RTP-induced V-O complexes in both Cz-Si and Cz-Si 1-x Ge x . As an indirect characterization means, the so-called 'platinum (Pt) or gold (Au) marker method' has been used to detect the RTPinduced vacancy species in Cz-Si [17,18]. The main point of this method is that under appropriate conditions the interstitial metal M I (M = Pt or Au) is converted to the substitutional metal M s by filling the vacancy species, as expressed by: M i ?…”