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Deuterium-doped indium tin oxide films, fabricated by dc plasma deposition in sputter gas consisting of deuterium and argon, were annealed at 300 °C for 40 min in flowing oxygen gas by using tubular gold image furnace. On oxygen annealing, the optical transparency of the film deposited at the gas pressure ratio of deuterium to argon of 3.6% increased from ≈30 to 60% at the wavelength of 600 nm, although that of the films deposited at the ratios of 1 and 1.5% slightly decreased from 88 to 80% and from 85 to 77%, respectively. The resistivity of the films at room temperature, ranged from 2 × 10−4 to 1.4 × 10−3 Ω cm corresponding to the gas pressure ratio from 1 to 3.6%, was almost the same before and after the annealing for each film. A change in morphology toward a smoother surface by the oxygen annealing was apparent especially for the film with the gas pressure ratio of 3.6%. Agglomeration of randomly oriented grains with diameters of

Thin films of indium tin oxide (ITO) sputter-deposited by dc-plasma containing deuterium on glass substrate without any heat treatments exhibited gradual lowering in electrical resistivity with increasing the deuterium content [D2] in plasma gas by 1% and then demonstrated a jump in resistivity by further increase of [D2] than 1%. X-ray photoelectron spectroscopy revealed that hydroxyl-bonded oxygen in ITO grew continuingly with [D2]. Deuterium positioned at the interstitial site increased almost quantitatively with increasing [D2]. Rutherford backscattering spectroscopy showed gradual reduction in the oxygen content of ITO with increasing [D2] by 1% and then demonstrated an abrupt increase of the oxygen content with the increase of [D2] than 1%. The films with [D2] < 1% were oxygen deficient, but those with [D2] > 1% were excess of oxygen. The most oxygen deficient film of [D2] = 1% was the most conductive. Behavior in the resistivity with [D2] looks parallel to that in the oxygen content. A lower resistivity of the films corresponded well to oxygen vacancy rather than hydrogen interstitial.

Indium tin oxide (ITO) thin films were sputter deposited by using working gas containing hydrogen on glass substrate without any heat treatments. The films demonstrated X-ray diffraction due to polycrystalline ITO, blue-green photoluminescence (PL) due to oxygen defects in nano-structured ITO crystals, and paramagnetic behaviour in temperature dependence of magnetization overlapped with diamagnetic signal from the substrate. The carrier density n of the films was of the order of 1020 cm−3, and varied as an inverse of V-character with the hydrogen concentration [H] in the gas. The n value peaked at [H] = 1%. Spectral features at ≈430 and ≈470 nm of the PL emission were invariant with [H]. The order of the density of electrons N with spins obeying the Curie law was 1023 cm−3, and the variation in N with [H] was almost parallel to that in n with [H].

Surface morphology and microstructure of indium tin oxide (ITO) thin films sputter deposited without heat treatment were obviously different from each other depending on the hydrogen concentration [H] in the working gas. The film surface became smoother with increasing [H] to 1%, but nucleation and growth of grains were apparent above [H] = 1.5%. The width of columnar grains in the ≤200 nm-thick films narrowed from ≈100 nm to ≈50 nm with increasing [H] from 0% to 1.5%. Randomly oriented and agglomerated grains were observed for the film deposited with [H] = 3.6%. Hydrogen added to the working gas induced reduction of the grain size, and then resulted in lowering of the carrier mobility.

Polycrystalline thin films of indium tin oxide sputter-deposited in the working gas containing hydrogen of 0.3–1.5% exhibited transmittance of ≥ 80% for visible lights and blue-shift of ≥ 0.1 eV in the optical absorption energy. The film deposited in the gas containing hydrogen of 1% demonstrated almost flat temperature-dependent resistivity and the lowest resistivity of ≈ 1.5 × 10− 4 Ω cm at room temperature. The carrier density showed an inverse V-shaped behavior with the maximum at the hydrogen concentration of 1%. The mobility stayed at almost constant below the hydrogen concentration of 1% and dropped rather rapidly above 1%.

Quantitative analysis of hydrogen and deuterium coadsorbed on clean Si(111) surfaces has been carried out by elastic recoil detection analysis using a 6 MeV F 3+ ion beam under an ultra high vacuum condition. H adsorption processes onto D-saturated Si(111) surfaces and vice versa have been studied in situ.

A newly designed high-resolution LEIS (low-energy ion scattering spectrometry) apparatus combined with LEED (low energy electron diffraction) is presented together with its performance characteristics. It has been developed for studies of the fundamental processes associated with low energy ion—surface interactions. The most original feature is that an assembled unit is devised to avoid the uncertainty of scattering geometries, which include the following mechanisms: the rotation of the analyzer mounted on a turntable, the manipulation of a sample holder and the collimation of an incident beam. Results of the high-resolution spectrometry of the scattered He+ ions are shown for He+-Si(111) and He+-In combinations. Moreover, the observed inelastic losses are discussed.