Trapping of atomic hydrogen in silicon by disordered regions

Abstract

This paper addresses issues related to migration and acceptor neutralization of hydrogen (H) in crystalline Si. From spreading resistance measurements, it is shown that disordered regions, both surface and subsurface, directly inhibit the penetration of H. Further, these effects are shown to be independent of the kind of disorder and the method of hydrogenation. Secondary-ion mass spectrometry profiles of deuterated samples confirm the suppression of deuterium movement through the disordered regions. We observe that annealing of these hydrogenated damage regions results in generation of an acceptor deactivation profile which is persistent for temperatures up to 800 °C and durations up to 1 min. This sustained deactivation phenomenon results in up to four decade change in free-carrier concentration. Our results unequivocally suggests that H-soaked damage region acts as a source of atomic hydrogen under rapid thermal annealing.

Enhancement of He-induced cavities in silicon by hydrogen plasma treatment

“…[12][13][14] Depending on the treatment conditions, posthydrogenation annealing at temperatures higher than 400°C may lead to the transformation of vacancy-type defects into large platelets due to the presence of hydrogen. This results in the growth of bigger cavities at the expense of smaller ones.…”

Post-hydrogenation of low-pressure chemical vapour deposited amorphous silicon

“…By post-hydrogenation they could recover the initial properties. Srikanth and Ashok [13] have reported hydrogenation of polycrystalline and amorphous silicon and they found that post-hydrogenation through the disordered region has very low penetration depth. They tried two different hydrogenation processes, implantation and electron cyclotron resonance (ECR) plasma, and found the same results.…”

Modification of MeV He Implantation-Induced Cavities in Silicon by Hydrogen Plasma Treatment

“…Therefore, during subsequent annealing hydrogen could be captured in other defects (i.e. vacancy-type defects for He implantation), and retard the annealing-out of the defects if these defects are present in the same sample [20]. Moreover, in-diffusion of hydrogen into the developing cavities could also generate additional internal pressure within the cavities.…”