Solutal Convection During Growth of Alloyed Semiconductor Crystals in a Magnetic Field

2003 ◽  
Vol 17 (1) ◽  
pp. 77-81 ◽  
Author(s):  
Nancy Ma
Keyword(s):  
Magnetic Field ◽  
Solutal Convection ◽  
Semiconductor Crystals ◽  
Alloyed Semiconductor

scholarly journals Growth of Binary Alloyed Semiconductor Crystals by the Vertical Bridgman-Stockbarger Process with a Strong Magnetic Field

2005 ◽  
Vol 127 (3) ◽  
pp. 523-528 ◽  
Author(s):  
Stephen J. LaPointe ◽  
Nancy Ma ◽  
D. W. Mueller
Keyword(s):  
Magnetic Field ◽  
Axial Magnetic Field ◽  
Convective Transport ◽  
Transient Model ◽  
Buoyant Convection ◽  
Semiconductor Crystals ◽  
Thermally Driven ◽  
Vertical Bridgman ◽  
Compositional Variations ◽  
Alloyed Semiconductor

This paper presents a model for the unsteady species transport for the growth of alloyed semiconductor crystals during the vertical Bridgman-Stockbarger process with a steady axial magnetic field. During growth of alloyed semiconductors such as germanium-silicon (GeSi) and mercury-cadmium-telluride (HgCdTe), the solute’s concentration is not small, so that density differences in the melt are very large. These compositional variations drive compositionally driven buoyant convection, or solutal convection, in addition to thermally driven buoyant convection. These buoyant convections drive convective transport, which produces nonuniformities in the concentration in both the melt and the crystal. This transient model predicts the distribution of species in the entire crystal grown in a steady axial magnetic field. The present study presents results of concentration in the crystal and in the melt at several different stages during crystal growth.

A geometric approach to dislocation densities in semiconductors

2014 ◽  
Vol 28 (15) ◽  
pp. 1450124
Author(s):  
K. Bakke ◽  
F. Moraes
Keyword(s):  
Magnetic Field ◽  
Dislocation Density ◽  
Bound States ◽  
Defect Density ◽  
Geometric Model ◽  
Energy Levels ◽  
Geometric Approach ◽  
Near Band Edge ◽  
Semiconductor Crystals ◽  
Dislocation Densities

Dislocation densities threading semiconductor crystals are a problem for device developers. Among the issues presented by the defect density is the appearance of the so-called shallow levels. In this work, we introduce a geometric model to explain the origin of the observed shallow levels. We show that a uniform distribution of screw dislocations acts as an effective uniform magnetic field which yields electronic bound states even in the presence of a repulsive Coulomb-like potential. This introduces energy levels within the band gap, increasing the carrier concentration in the region threaded by the dislocation density and adding additional recombination paths other than the near band-edge recombination. Our results suggest that one might use a magnetic field to destroy the dislocation density bound states and therefore minimize its effects on the charge carriers.

On the high growth rates in electroepitaxial growth of bulk semiconductor crystals in magnetic field

2005 ◽  
Vol 275 (1-2) ◽  
pp. e1-e6 ◽  
Author(s):  
Sadik Dost ◽  
Hamdi Sheibani ◽  
Yongcai Liu ◽  
Brian Lent
Keyword(s):  
Magnetic Field ◽  
Growth Rates ◽  
High Growth ◽  
Semiconductor Crystals ◽  
Bulk Semiconductor

scholarly journals Analysis of magnetic properties of A3B6 type of semiconductor crystals with metalic impurities due to their military applications

2021 ◽  
pp. 8-12
Author(s):  
Bohdan Seredyuk
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Interlayer Space ◽  
Van Der Waals ◽  
Covalent Bond ◽  
Magnetic Sensors ◽  
Metal Impurities ◽  
Semiconductor Crystals ◽  
Strong Covalent Bond ◽  
The Magnetic Field

The Earth's magnetic field is affected by the presence of heavy military armored vehicles which creates an additional magnetic moment. This distortion of the magnetic field, can be detected using magnetoresistive structures. This article touches base on the possibility of using semiconductor material such as InSe for high precision measurement of the magnetic field. The properties of InSe structures with regard to electrical, magnetic and optical characteristics are discussed. The effect of sharp anisotropy of InSe layered structure which consists in the strong covalent bond within the layers and a weak van-der-Waals bond in the interlayer space is discussed with regard to the explanation of how electrical, magnetic and optical properties are altered. The peculiarity of the spatial orientation of the material with regard to the direction of the magnetic field is considered. The impact of intercalation of InSe, GaSe by various concentrations of metal impurities such as nickel and other elements of 3d iron group is studied. Bode diagrams for pure InSe system are compared with the ones of NixInSe (for various x values). Also the effect of different temperatures ranging from room temperature to liquid nitrogen on the pattern of Bode diagrams is analyzed. The extent of how the magnetic properties of semiconductor crystals of the A3B6 type are altered by the presence of the metal impurities and their concentration is analyzed. Theoretic background for this paper is based on a well-known statement that layer structures such InSe or other A3B6 structures can be viewed as quasi two-dimensional. So, layers with strong covalent bond are formed by In-Se atoms, whereas interlayer space is filled with a weak Van der Waals bond. Within this model the processes across the layers can be described as a perturbation to the ones along the layers.  This causes a strong anisotropy of the properties of these structures. Military implication of InSe structures mentioned throughout this paper is that these structures possess magnetoresistive properties and they were proved to be useful for the components of the magnetic sensors of civil and military use. This paper also touches base on how the InSe semiconductor crystals intercalated by 3d-elements can extend the functionality of magnetic sensors designed for heavy armor detection.

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