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Hydrogen nuclear magnetic resonance(NMR) was used to probe defect reactions in fused silica during 193 nm ultraviolet irradiation and thermal treatment. Hydrogen concentration and Carr–Purcell measurements indicate that the majority of hydrogen atoms are isolated and do not segregate or evolve from the fused silica during annealing or irradiation. Previously, NMR spin‐lattice relaxation measurements have revealed that a small fraction of hydrogen in fused silica exists as centers that undergo molecular motion and are consumed during annealing. Here, a detailed analysis of the NMR spin‐lattice relaxation behavior is used to support the identification of this center as a pair of adjacent silanol groups. These silanol pairs react during annealing to form a strained bond, thus increasing the susceptibility of fused silica to E’formation. Excimer laser irradiation, like thermal treatment, is shown to directly reduce the number of relaxation centers in the material. The measured dependence of spin‐lattice relaxation as a function of irradiation for identically prepared samples is consistent with silanol pair center consumption by a two‐photon process.

1 H NMR spectra were obtained for silicon dioxide films that were thermally grown under clean room conditions. Bulk hydrogen in a concentration of approximately 1.2×10 198 H/cm 3 was detected in a 1.1-μm thick wet oxide grown at 1000 o C. The relatively long (∼15 s) spin-lattice relaxation time for this sample is consistent with bulk hydrogen, while a narrow 3 kHz half-width at half maximum (HWHM) Gaussian line shape suggests that the majority of hydrogen in this film is well isolated. Thinner thermal oxides, own under a variety of conditions, were exposed to the ambient to assess the effects of sample aging

The design for a nuclear magnetic resonance (NMR) probe capable of detecting hydrogen signals at levels of

Hydrogen distribution in various solid system was studied by multiple quantum (MQ) nuclear magnetic resonance (NMR). The rate of growth of MQ coherences for bulk infinite, three-dimensional hydrogen lattice found in materials such as calcium hydride, sodium bicarbonate, and adamantane followed a universal growth curve when the time axix was scaled by a the square root of the second moment (M 2 1/2 ), while three chemically vapor deposited diamond films and a natural diamond powder sample showed a noted departure from this universal growth curve

Nuclear magnetic resonance (NMR) was used to study hydrogen in fused silica for the first time. The 1H NMR spin‐lattice relaxation time constant (T1) in synthetic fused silica was found to be strongly affected by thermal treatments, correlating with the concentration of E’ centers produced during subsequent 193‐nm excimer‐laser irradiation. In addition, the relative proportion of the two components in the NMR spectrum were affected by thermal treatment, although no change in the total hydrogen content was observed. The broad NMR component, because of its linewidth and dependence upon thermal processing, is postulated to be a direct signature of the NMR relaxation centers. These results are interpreted within the framework of a model in which pairs of silanol groups are consumed during thermal treatment, forming a strained bond which is susceptible to E’ center formation.

Hydrogen incorporated into polycrystalline diamond was found to correlate with the optical absorption in the 8 to 10 μm wavelength IR region, where transparency is desired. In this first detailed study of diamond films by 1H NMR, average concentrations were found to be

Hydrogen is a common impurity in silicon dioxide (SiO2) which can influence its optical and electronic properites. Here, nuclear magnetic resonance (NMR) is applied to study of hydrogen in these materials, despite their relatively low hydrogen content. We present results for bulk fused silica as well as thermally grown films of SiO2 on silicon. These experiments demonstrate the potential of solid state NMR for studying low hydrogen content film systems. In bulk fused silica, we have observed that although the majority of hydrogen is isolated, a small number of centers exist involving adjacent silanol pairs. These pairs react during high temperature annealing as well as during deep ultraviolet irradiation. Furthermore, the presence of these centers is related to the susceptibility of fused silica to radiation damage. The results obtained on the fused silica material are compared to SiO2 films on silicon. The NMR spectra and relaxation associated with thick (>1μm) wet SiO2 films are similar to those for the fused silica while the NMR data for thinner oxide more closely resembles those of surface water on silica gel.

An IR and multiple quantum NMR (MQNMR) study of hydrogen microstructure in three boron doped a-Si:H is discussed. The total Si-bonded H content of all films was 6.5 ± 1.0 at.% as determined by the 640 cm-1 IR wagging mode, but their boron content, which was determined by secondary ion mass spectrometry, ranged from 0.02 to 0.3 at. %. The number of correlated hydrogen, as measured at a preparation time of 600 μSwas found to be more weakly dependent on the boron content than previously observed in phosphorous-doped glow-discharge films. Upon annealing at 220 °C the MQNMR spectrum show a moderate increase in the number of correlated hydrogen in all three samples.

We have used solid state nuclear magnetic resonance (NMR) spectroscopy to study both “wet” and “dry” thermally grown films of SiO2 on silicon substrates. For the 5000 § wet film, grown at 1050 °C we observed a single Lorentzian line of 6 kHz HWHM (half width at half maximum). For the 500 § dry film, we observed a convolution of two lines: a) a Lorentzian of 4 kHz HWHM and b) a Gaussian of 20 kHz HWHM. The hydrogen distributions in both oxides are interpreted as a function of these lines.