Hydrogen passivation

There are several reports of the use of directed ion sources to hydrogen passivate both shallow impurities (Horn et al., 1987 Martinuzzi et al., 1985) and deep defect levels in silicon (Dube and Hanoka, 1984 Hanoka... 

Fig. 2. IR absorption spectrum of hydrogen passivated, B-doped Si measured at room temperature. [Reprinted with permission from the American Institute of Physics, Pankove, J.I., et al., (1985). Appl. Phys. Lett. 46, 421.]...

The new vibrational features that were found in the hydrogen passivated n-type layers are shown in Figs. 9 and 10. The frequencies, widths, and relative strengths are given in Table II. There are two near-lying bands above 1500 cm 1 and a third band at 809 cm 1 for each of the three... 

The description of channeling measurements on hydrogen-passivated boron-doped layers has shown that there is broad agreement on the main features of the experimental data from the different groups, if we leave aside data that is strongly influenced by radiation damage caused by the... 

Hydrogen Passivation of Deep Level Impurities and Defects 372... 

Besides the electrically active complexes discussed above, there is indirect evidence for the existence of neutral complexes. In close analogy to the observations in silicon and several III-V materials it appears that hydrogen passivates deep and shallow acceptors. Because of the small concentrations of these neutral centers, all attempts to detect them directly with local vibrational mode (LVM) spectroscopy or electron paramagnetic resonance (EPR) have been unsuccessful. 

In addition, a number of other deep level impurities have been hydrogen passivated. They include nickel, cadmium, tellurium, zirconium, titanium, chromium, and cobalt (Pearton et al., 1987). Most of these studies have been qualitative, and important work remains to be done if the hydrogenation of these and most probably additional impurities, such as gold, palladium, platinum and iron, is to be fully understood. 

J. iV. Corbett, P. Dedk, U. V. Desnica, and S. J. Pearton, Hydrogen Passivation of Damage Centers in Semiconductors... 

As an example, XPS has been used to analyze modifications induced by 2 to 20 eV electrons incident on a hydrogen-passivated and sputtered Si(lll) surface, onto which had been physisorbed thin films of H2O [293,294] and CF4 [295]. In both cases, following the electron-induced dissociation of the molecular adsorbate, a new XPS signal associated with the chemisorption of either O or F onto the Si surface was observed and an effective cross section for chemisorption was then calculated. This cross section for electron-induced chemisorption of oxygen from an H2O bilayer onto a hydrogen-passivated Si(l 11) surface is shown in Fig. 24 as a function of Ei [293,294]. The low energetic threshold for the chemisorption process (i.e., 5.2 eV) has been interpreted as due to the formation of OH via the DEA process... 

A similar XPS study has been performed for 1 ML of CF4 deposited onto the same hydrogen-passivated Si substrate [295] and clearly demonstrates that chemisorption of the F-containing species is dependent on the DEA reactions... 

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