The Electronic States and Dynamical Properties of Hydrogen Bound to Carbon in Silicon

1992 ◽  
Vol 262 ◽  
Author(s):  
Yoichi Kamiura ◽  
Fumio Hashimoto ◽  
Minoru Yoneta

ABSTRACTThis paper demonstrates a unique action of hydrogen on defects and impurities in semiconductors. Hydrogen injected into n-type Si by chemical etching or hydrogen plasma not only pas-sivatcs phosphorus but also electrically activates carbon by forming a H-C complex acting as an electron trap E3 (0.15). A model of the structure and electronic state of the H-C complex is proposed on the basis of available experimental data on the properties of the complex. The diffusion coefficient of isolated hydrogen below 300K is evaluated from its diffusion process to phosphorus after the photoinduccd dissociation of the H-C complex. Some differences in hydrogen diffusion between chemically etched and plasma hydrogenated crystals arc discussed.

1975 ◽  
Vol 53 (19) ◽  
pp. 2079-2084 ◽  
Author(s):  
A. Delage ◽  
J.-D. Carette

The spectrum of electronic states of krypton I has been measured by inelastic scattering of monoenergetic electrons with the aid of an electron spectrometer which has a high resolving power, ΔE/E = 0.02. Electron energy loss spectra have allowed us to detect and identify numerous electronic states of krypton I for the first time by the means of this experimental method. The relative heights of the peaks corresponding to an energy loss, which are related to the probability of excitation of the atom by electron impact to a given state, have been measured from experimental data as a function of the energy incident electrons and as a function of the scattering angle.


1991 ◽  
Vol 219 ◽  
Author(s):  
Y. S. Tsuo ◽  
Y. Xu ◽  
D. W. Baker ◽  
S.K Deb

ABSTRACTWe have studied wet-chemical and dry etching properties of doped and undoped hydrogenated amorphous silicon (a-Si:H) films with bonded hydrogen content varying from 0 to 20 at.%. Etching processes studied include (1) wet-chemical etching using solutions of KOH, isopropyl alcohol (IPA), and H2O, (2) hydrogen plasma etching, and (3) XeF2 vapor etching.


1974 ◽  
Vol 52 (19) ◽  
pp. 1862-1871
Author(s):  
J. David Brown ◽  
George Burns

The temperature dependence of emission from iodine, heated in a shock wave to 1000 K–2000 K, has been measured at 4550, 5550, 6950, 7550, and 7820 Å. Preliminary measurements of the emission at 6380 Å were also made. The temperature dependence of the emission was calculated at these wavelengths for transitions to the ground electronic state X(1Σg+) of iodine from the excited electronic states, A(3Π1u), (1Π1u), and [Formula: see text]. The calculated results are in a reasonable agreement with experimental data. For the banded emission due to the B → X transition, a theory of the temperature dependence of emission was developed. At 6950, 7550, and 7820 Å, the results of this theory agree with the experimental data thus identifying the B → X transition as the source of emission at these wavelengths. The temperature dependence of emission at 4550 Å is consistent with calculated temperature dependence for either (1Π1u) → X or [Formula: see text] transitions. The temperature dependence of the emission at 5550 Å is consistent with calculated temperature dependence for the above two transitions, as well as for the A(3Π1u) → X transition.


1962 ◽  
Vol 40 (5) ◽  
pp. 598-606 ◽  
Author(s):  
Jon T. Hougen

Expressions are derived for the rotational energy levels of diatomic molecules in 4Σ states. These expressions contain two rho-type doubling parameters (γ's), and thus differ from earlier expressions which contain only one such parameter. The new expressions are in better agreement with the experimental data, though some discrepancy still exists.


2011 ◽  
Vol 111 (7-8) ◽  
pp. 1316-1320 ◽  
Author(s):  
Alessandra S. Kiametis ◽  
Thiago A. M. Matheus ◽  
A. L. A. Fonseca ◽  
Geraldo Magela E Silva ◽  
Ricardo Gargano

2005 ◽  
Vol 864 ◽  
Author(s):  
F. Kail ◽  
A. Hadjadj ◽  
P. Roca i Cabarrocas

AbstractWe have studied the evolution of the structure of boron-doped hydrogenated amorphous silicon films exposed to a hydrogen plasma. From the early stages of exposure, hydrogen diffuses and forms a thick H-rich subsurface. At longer times, hydrogen plasma leads to the formation of a microcrystalline layer via chemical transport without crystallization of the initial layer. We observe that the hydrogen content increases in the films during a plasma exposure and once the microcrystalline layer is formed hydrogen diffuses out of the sample accompanied with a decrease in the boron content. This effect can be attributed to the electric field developed within the heterojunction a-Si:H/μc-Si:H that drives the positively charged hydrogen atoms in the boron-doped layer towards the μc-Si:H layer.


2018 ◽  
Vol 115 (38) ◽  
pp. 9444-9449 ◽  
Author(s):  
Rui Shi ◽  
John Russo ◽  
Hajime Tanaka

Liquids can be broadly classified into two categories, fragile and strong ones, depending on how their dynamical properties change with temperature. The dynamics of a strong liquid obey the Arrhenius law, whereas the fragile one displays a super-Arrhenius law, with a much steeper slowing down upon cooling. Recently, however, it was discovered that many materials such as water, oxides, and metals do not obey this simple classification, apparently exhibiting a fragile-to-strong transition far above Tg. Such a transition is particularly well known for water, and it is now regarded as one of water’s most important anomalies. This phenomenon has been attributed to either an unusual glass transition behavior or the crossing of a Widom line emanating from a liquid–liquid critical point. Here by computer simulations of two popular water models and through analyses of experimental data, we show that the emergent fragile-to-strong transition is actually a crossover between two Arrhenius regimes with different activation energies, which can be naturally explained by a two-state description of the dynamics. Our finding provides insight into the fragile-to-strong transition observed in a wide class of materials.


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