A variationally computed room temperature line list for AsH3

The concept of fully encapsulated, semi-insulating silicon (SI-Si), Czochralski-silicon-on-insulator (CZ-SOI) substrates for silicon microwave devices is presented. Experimental results show that, using gold as a compensating impurity, a Si resistivity of order 400 kΩcm can be achieved at room temperature using lightly phosphorus doped substrates. This compares favourably with the maximum of ~180kΩcm previously achieved using lightly boron doped wafers and is due to a small asymmetry of the position of the two gold energy levels introduced into the band gap. Measurements of the temperature dependence of the resistivity of the semi-insulating material show that a resistivity ~5kΩcm can be achieved at 100°C. Thus the substrates are suitable for microwave devices working at normal operating temperatures and should allow Si to be used for much higher frequency microwave applications than currently possible.

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The principal magnetic susceptibilities of neodymium sulphate octahydrate at low temperatures

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1939.0031 ◽

1939 ◽

Vol 170 (941) ◽

pp. 266-271 ◽

Cited By ~ 3

Keyword(s):

Low Temperatures ◽

Room Temperature ◽

Energy Levels ◽

Constant Factor ◽

The Other ◽

Crystalline Field ◽

Cubic Symmetry ◽

The Subject ◽

The Difference ◽

The One

The magnetic and other related properties of neodymium sulphate have been the subject of numerous investigations in recent years, but there is still a remarkable conflict of evidence on all the essential points. The two available determinations of the susceptibility of the powdered salt at low temperatures, those of Gorter and de Haas (1931) from 290 to 14° K and of Selwood (1933) from 343 to 83° K both fit the expression X ( T + 45) = constant over the range of temperature common to both, but the constants are not the same and the susceptibilities at room temperature differ by 11%. The fact that the two sets of results can be converted the one into the other by multiplying throughout by a constant factor suggested that the difference in the observed susceptibilities was due to some error of calibration. It could, however, also be due to the different purity of the samples examined though the explanation of the occurrence of the constant factor is then by no means obvious. From their analysis of the absorption spectrum of crystals of neodymium sulphate octahydrate Spedding and others (1937) conclude that the crystalline field around the Nd+++ ion is predominantly cubic in character since they find three energy levels at 0, 77 and 260 cm. -1 .* Calculations of the susceptibility from these levels reproduce Selwood’s value at room temperature but give no agreement with the observations-at other temperatures. On the other hand, Penney and Schlapp (1932) have shown that Gorter and de Haas’s results fit well on the curve calculated for a crystalline field of cubic symmetry and such a strength that the resultant three levels lie at 0, 238 and 834 cm. -1 , an overall spacing almost three times as great as Spedding’s.

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Electrical Properties of Nanostructure n-ZnSe/p-Si(100) Heterojunction Thin Film Diode

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.775.246 ◽

2018 ◽

Vol 775 ◽

pp. 246-253

Author(s):

Ngamnit Wongcharoen ◽

Thitinai Gaewdang

Keyword(s):

Thin Films ◽

Ideality Factor ◽

Room Temperature ◽

Energy Levels ◽

Thermionic Emission ◽

Depletion Region ◽

Trap Level ◽

Characteristic Energy ◽

Znse Thin Films

The ZnSe/Si heterojunction is of specific interest since this structure provides effective solar cell and enables the integration of wide bandgap device in silicon circuits. It is known that the quality of the diode and the current transport mechanisms across the heterojunction may be greatly influenced by the quality of the interface and depends on the crystallinity of the film layer. In this work, n-ZnSe/p-Si (100) heterojunction was fabricated by thermal evaporating ZnSe thin films on p-Si (100) substrates. The current-voltage characteristics of n-ZnSe/p-Si (100) heterojunction were investigated in temperature range 20-300 K. Some important parameters such as barrier height, ideality factor and series resistance values evaluated by using thermionic emission (TE) theory and Cheung’s method at room temperature are n = 2.910,φB0= 0.832 eV and 8.59103Ω, respectively. The temperature dependence of the saturation current and ideality factor are well described by tunneling enhanced recombination at junction interface with activation energy and characteristic energy values about 1.293 eV and E00= 95 meV, respectively. The carrier concentration of ZnSe thin films about 3.16×1013cm-3was deduced from the C-V measurements at room temperature. Admittance spectroscopy was employed for analysis of the defect energy levels situated in depletion region. The results showed that there was a single trap level whose position in the band gap was close to 0.04 eV above valence band. The results of this work may be useful for application such as heterojunction solar cells.

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Rotation-vibration energy levels of CH3

Journal of Molecular Spectroscopy ◽

10.1016/0022-2852(91)90077-n ◽

1991 ◽

Vol 147 (2) ◽

pp. 541-542 ◽

Cited By ~ 10

Author(s):

V. S̆pirko ◽

W.P. Kraemer

Keyword(s):

Energy Levels ◽

Vibration Energy

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Study of the Radiative and Non-Radiative Recombination Processes at Dislocations in Silicon by Photoluminescence and LBIC Measurements

MRS Proceedings ◽

10.1557/proc-588-117 ◽

1999 ◽

Vol 588 ◽

Cited By ~ 6

Author(s):

S. Pizzini ◽

S. Binetti ◽

M. Acciarri ◽

M. Casati

Keyword(s):

Radiative Recombination ◽

Room Temperature ◽

Light Emission ◽

Energy Levels ◽

The Third ◽

Optical Telecommunications ◽

Recombination Processes ◽

Metallic Impurities ◽

Room Temperature Luminescence ◽

Dislocation Related Luminescence

AbstractIt is well known that the sharp, room temperature luminescence emission at 1.54 μm from dislocated silicon has set off a great interest for this material in view of its applications in the third window of optical telecommunications. For this reason the dislocation related luminescence in silicon addressed recently a number of investigation aimed at understanding the mechanism of light emission. The problem is still unsolved as most of the experiments done gave contradictory answers to the main questions open, which concern the intrinsic or extrinsic nature of dislocation luminescence and the effect on it of reconstruction, interaction or passivation processes, possibly assisted by metallic or non-metallic impurities.In order to go more insight on the problem, we started a systematic work on CZ silicon, aimed at understanding the properties of dislocation luminescence. The identification of the energy levels involved in the different dislocation PL bands has been obtained.

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