On the permeation of hydrogen and helium in single crystal silicon and germanium at elevated temperatures

doi:10.1016/S0031-8914(56)90039-8

Physica

Volume 22, Issues 6–12, 1956, Pages 849-865

https://doi.org/10.1016/S0031-8914(56)90039-8 Get rights and content

Synopsis

A mass spectrometer examination of the permeability of the elements silicon and germanium to the gases hydrogen and helium has been carried out in the temperature range 967–1207°C for silicon and 766–930°C for germanium.

Using certain crystal growing and cutting techniques two kinds of diffusion cells were made by each of which it was possible to determine both diffusion coefficient and solubility as well as the activation energies of diffusion and solution from non-steady-state permeation measurements. No permeation of the gases neon, argon and nitrogen could be detected. It seems that hydrogen in silicon can occur both in elemental form and as a compound. The elemental form diffuses easily and consists mainly of atoms or protons.

References (13)

GüntherschulzeA. et al.
Z. Physik
(1939)
Le ClaireA.D. et al.
Rev. Métallurgie
(1955)
MullerJ.H. et al.
HagenH. et al.
Z. Anorg. Al1g. Chemie
(1930)
IwaseK. et al.
Nippon Kinzoku Gakukai-Si
(1937)
IwaseK. et al.
C.A.
(1938)
TealG.K. et al.
Phys. Rev.
(1950)

There are more references available in the full text version of this article.

Cited by (479)

Generation and loss of hydrogen-boron pairs in fired silicon wafers
2023, Materials Science in Semiconductor Processing
A dark anneal of fired B-doped samples is known to generate HB pairs which is followed by a loss of HB upon a prolonged anneal. In this paper, the reported data on the evolution of the total concentration of free and trapped ions, C = [H⁺] + [HB] (with a dominant contribution of HB) are used to extract the model parameters α (the dissociation coefficient of quenched-in hydrogen dimers, H_2A), χ (the constant relating [H_2A] and [HB] under equilibrium), β (the kinetic coefficient for the production of stable dimers, H_2C). A loss of HB can be caused also by hydrogen out-diffusion; the computed diffusion-limited loss, surprisingly, is well faster than the observed loss. The reasons for this discrepancy are discussed. One possibility is that the hydrogen is trapped by boron initially into a metastable state with subsequent transformation into a stable state, of a lower effective diffusivity. This concept is supported by a peculiar evolution of [HB] observed under room-temperature illumination.
Improvement of passivation performance of silicon nanocrystal/silicon oxide compound layer by two-step hydrogen plasma treatment
2023, Solar Energy Materials and Solar Cells
A two-step hydrogen plasma treatment (HPT) is carried out for Si nanocrystals/silicon oxide compound passivating contacts to improve their passivation performance. The 2-step HPT consists of a first HPT at a high temperature of 500 °C and a second HPT at a lower temperature of 300 °C. Etching of n-type polycrystalline Si (n⁺-poly-Si) is suppressed by using low RF power and short duration as the condition for the second HPT. For the passivating contact with thin n⁺-poly-Si, the implied open-circuit voltage (i-V_OC) was improved to 723 mV after the 2-step HPT, which is higher than the i-V_OC after the one-step HPT (718 mV) owing to enhanced hydrogenation of the Si nanocrystals/silicon oxide compound layer. On the other hand, 1.4-fold larger contact resistivity (ρ_c) was obtained after the 2-step HPT. This increase in ρ_c is probably attributed to the suppression of trap-assisted tunneling. The largest i-V_OC value of 744 mV and the lowest ρ_c value of 12 mΩ cm² was observed for the contact with 300-nm-thick n⁺-poly-Si, possibly due to enhanced field-effect passivation after the 2-step HPT.
Correlation study between LeTID defect density, hydrogen and firing profile in Ga-doped crystalline silicon
2023, Solar Energy Materials and Solar Cells
Light- and elevated Temperature-induced Degradation (LeTID) remains a challenge for the long-term stability of silicon-based solar cells. Despite numerous publications and studies on the subject, only a link with the hydrogen concentration in the silicon bulk has been established. However, the question remains as to how exactly hydrogen interacts with the defect or even forms part of it.
In this study, highly sensitive resistivity measurements and photoluminescence/ photoconductance decay measurements are used to establish a precise correlation between the dominant hydrogen species (H $_{2}$ and GaH) and the evolving defect concentration in fired Ga-doped silicon coated with an hydrogen-rich amorphous silicon nitride (SiN $_{x}$ :H).
The correlation appears to be linear in both species over the range investigated but the data imply that the defect concentration is proportional to H $_{2}$ . An investigation of the behavior of GaH during typical degradation conditions confirms that GaH pairs are hydrogen sinks and therefore do not contribute to the formation of LeTID defects. We therefore expect the hydrogen dimer to act as a precursor for LeTID.
In addition, the indiffusion of H during the firing step from a SiN $_{x}$ :H layer was investigated and a strong dependence on the peak temperature was found, whereas a weaker dependence on the cooling rate was observed.
Self-formation of SiGe oxide, Ge, and void multilayers via thermal oxidation of hydrogenated epitaxial SiGe films
2023, Vacuum
In this work, hydrogenated SiGe thin films epitaxially grown on crystalline Si (c-Si) at 175 °C are annealed at 800 °C in a low vacuum system. The influence of H from the thin film and residual O atoms in the vacuum system on the structural changes of SiGe is presented. Multilayers consisting of c-Si/SiGe/void/Ge/SiO_x/SiGeO_x are obtained by taking advantage of the hydrogen present in the epitaxial SiGe layer. Various annealing conditions are applied to study the evolution of SiGe layers. The surface morphology, crystallinity, composition and micro structure of the multilayer stack formed during the annealing process are investigated in detail. A discussion based on the diffusion of H and O atoms is presented to account for this extraordinary process.
Cross section of 15N-2D nuclear reactions from 3.3 to 7.0 MeV for simultaneous hydrogen and deuterium quantitation in surface layers with 15N ion beams
2020, Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
Citation Excerpt :
Decreased 2D-derived γ-yield, for instance, may then arise either from 2D loss from the target (such as from desorption or 1H/2D isotope exchange) as well as from a redistribution of 2D into deeper bulk regions, where the probing 15N energy is reduced by stopping and hence the effective 15N-2D cross section smaller. The 15N-2D NRA method should nonetheless be useful whenever the depth location of the 2D in the sample is rigidly confined to a narrow depth region by the target material and structure in the depth dimension, such as in the present case of the thin a-C:D films, where the 2D solubility in the Si substrates is far below the NRA detection limit [27]. For similar such systems, we therefore expect the method to be highly promising to investigate 1H/2D exchange or diffusion processes in surface thin films or in buried thin layers of 1H/2D-containing functional materials by means of isotopic tracing.
The cross section for the combined ²D(¹⁵N,p)¹⁶N and ²D(¹⁵N,nγ)¹⁶O nuclear reactions of deuterium (²D) with incident ¹⁵N ions is evaluated and found to increase by two orders of magnitude between 3.3 and 7.0 MeV. Detecting the γ-rays at 6.1 and 7.1 MeV from these reactions allows quantifying the depth-integrated ²D content in materials in parallel with nanometer-resolved quantitative hydrogen (¹H) depth profiling in surface layers through resonant ¹H(¹⁵N,αγ)¹²C nuclear reaction analysis (NRA) using ¹⁵N ion beams. The information depth and sensitivity of ¹⁵N-²D NRA is estimated through energy loss simulations of the ¹⁵N projectiles in the analyzed material. Good agreement of the integral ²D quantitation through ²D(¹⁵N,p)¹⁶N and ²D(¹⁵N,nγ)¹⁶O NRA with ²D depth profiles obtained independently via ²D(³He,p)⁴He NRA is demonstrated at the example of ²D plasma-exposed tungsten samples. The simultaneous quantitation of ²D and depth-resolved ¹H profiling with a single ¹⁵N ion beam promises application potential to investigate hydrogen-isotope exchange and diffusion processes in surface and thin buried layers.
Hydrogen-induced degradation: Explaining the mechanism behind light- and elevated temperature-induced degradation in n- and p-type silicon
2020, Solar Energy Materials and Solar Cells
Citation Excerpt :
The reported diffusivity DH(+/0/-) of H+ in p-type silicon at 150 °C is DH+ = 3 × 10−13 cm2s−1, whereas H− in n-type silicon is reported to have a diffusivity DH- = 3 × 10−10 cm2s−1, that is, three orders of magnitude quicker [60]. In both n- and p-type silicon, the neutral charge state of hydrogen, H0, is expected to have the greatest diffusivity (DH0 = 1.8 × 10−8 cm2s−1), due to its limited interaction with dopants and impurities [71]. If we consider our previous hypothesis in Ref. [39] that the recovery of LeTID may be related to the out-diffusion of hydrogen towards the wafer surfaces, it may be expected that in materials of opposing polarity or differing excess carrier injection, the variations in hydrogen charge state occupation should significantly alter the LeTID recovery reaction kinetics.
Light- and elevated temperature-induced degradation (LeTID) has been extensively studied on p-type silicon materials with increasing evidence suggesting the involvement of hydrogen. Recent findings of the identical phenomenon in n-type silicon wafers have further opened up new areas of understanding into the inherent behavior and root cause of the defect. In this work, we compare LeTID observed in both p- and n-type silicon wafers under both dark and illuminated annealing conditions, highlighting previously unobserved similarities in defect formation and recovery kinetics. We report thermal activation energies of the LeTID-related degradation and recovery in n-type silicon to be 0.76 ± 0.02 eV and 0.97 ± 0.01 eV without illumination, respectively, and 0.70 ± 0.05 eV and 0.83 ± 0.15 eV under illumination (0.02 kWm⁻²), respectively. Furthermore, we present additional experimentation demonstrating the thermal and illumination dependency of surface-related degradation (SRD) in n-type silicon. We report an extracted activation energy of this SRD of 0.38 ± 0.10 eV. Through modelling of the hydrogen charge state fractions, we speculate that the behavior of LeTID both in the dark and under illumination may be explained by the migration of and interactions between charged hydrogen species and dopant atoms within the diffused layers and the silicon bulk.

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Physica

Synopsis

References (13)

Z. Physik

Rev. Métallurgie

Z. Anorg. Al1g. Chemie

Nippon Kinzoku Gakukai-Si

C.A.

Phys. Rev.

Cited by (479)

Generation and loss of hydrogen-boron pairs in fired silicon wafers

Improvement of passivation performance of silicon nanocrystal/silicon oxide compound layer by two-step hydrogen plasma treatment

Correlation study between LeTID defect density, hydrogen and firing profile in Ga-doped crystalline silicon

Self-formation of SiGe oxide, Ge, and void multilayers via thermal oxidation of hydrogenated epitaxial SiGe films

Cross section of <sup>15</sup>N-<sup>2</sup>D nuclear reactions from 3.3 to 7.0 MeV for simultaneous hydrogen and deuterium quantitation in surface layers with <sup>15</sup>N ion beams

Hydrogen-induced degradation: Explaining the mechanism behind light- and elevated temperature-induced degradation in n- and p-type silicon