The vibrational lifetimes of the O-H and O-D stretch modes in the perovskite oxide KTaO3 are measured by pump-probe infrared spectroscopy. Both stretch modes are exceptionally long lived and exhibit a large “reverse” isotope effect, due to a phonon-assisted proton-tunneling process, which involves the O-Ta-O bending motion. The excited-state tunneling rate is found to be 7 orders of magnitude larger than from the ground state in the proton conducting oxide, BaCeO3 [Phys. Rev. B 60, R3713 (1999)]. (Read more)

First-principles plane-wave calculations were performed for hydroxyapatite (HAp) in order to investigate the electronic structure and vacancy formation mechanisms. The HAp unit cell contains PO₄ tetrahedra and OH groups formed by covalent P-O and H-O bonds. Ca ions play a role for... (Read more)

We present an overview of negative bias temperature instability (NBTI) commonly observed in p-channel metal–oxide–semiconductor field-effect transistors when stressed with negative gate voltages at elevated temperatures. We discuss the results of such stress on device and circuit... (Read more)

We used a density functional method to investigate the mechanism of negative-bias temperature instability (NBTI) and resultant structural changes of Si/SiO₂ and Si/SiO_xN_y interfaces. The reaction energies for the water- and hydrogen-originated... (Read more)

Infrared optical absorption has been used to study OH−impurities into congruent co-doped LiNbO3:Cr3+:ZnO crystals doped with different Zn2+ concentration. The OH− IR absorption spectra present three bands that can be associated with different OH− complex centres available in the... (Read more)

The diffusion and reactions of hydrogenous species generated by single-pulsed F₂ laser photolysis of SiO-H bond in SiO₂ glass were studied in situ between 10 and 330 K. Experimental evidence indicates that atomic hydrogen (H⁰) becomes mobile even at temperatures as... (Read more)