摘要:

A new model for pattern formation in semiconductor materials is proposed based essentially on kinetic processes of charge carriers. This model leads to a set of coupled nonlinear reaction‐diffusion equations with two components: the electron density in the conduction band and the occupation density of a trap level. The model possesses a variety of stable solutions including stable multifilament structures.

ISSN:0021-8979    

DOI:10.1063/1.342095

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

The steady‐state Nyquist theorem (or the steady‐state fluctuation‐dissipation theorem), which reduces to the Nyquist theorem in thermal equilibrium, is obtained for nondegenerate semiconductors by solving the Langevin‐type Boltzmann transport equations with the relaxation‐time approximation. This theorem is an extension of the Nyquist theorem to nonequilibrium systems for nondegenerate semiconductors. The derived theorem holds for any nondegenerate semiconductor device with one‐dimensional geometry when the quasi‐Fermi levels of electrons and holes can be defined for the steady‐state electron and hole distributions at any position inside the device, i.e., when at any position inside the device the steady‐state electron and hole distributions are not driven far away from the Maxwellian distributions. The derived theorem resembles almost exactly the functional form of the Nyquist theorem. As an application of this theorem the thermal noise in double‐injection space‐charge‐limited solid‐state diodes is calculated using this theorem.

ISSN:0021-8979    

DOI:10.1063/1.342096

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

ZnTe films have been prepared by hot wall epitaxy onto glass and single‐crystal potassium chloride substrates. The electron transport properties in polycrystalline and single‐crystal films have been reported. The electrical resistivity decreases very slowly up to dopant concentrations 1016at./cm3followed by a steep fall. The drift mobility appears to be fairly constant over a wide range of dopant concentrations, while it shows rapid decline on heavy doping.

ISSN:0021-8979    

DOI:10.1063/1.342097

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

A systematic analysis of static current‐voltage characteristics at variable temperatures of almost ideal siliconp‐njunctions has been carried out. This analysis shows that while in neutral region the generation and recombination mechanisms are characterized by the same lifetime, in the space‐charge region the generation lifetime may be significantly lower than the recombination lifetime: hence we infer the existence of a field‐assistance pure generation phenomenon. Evidence supporting the hypothesis that a unique center is responsible for all of the recombination phenomena is presented. This center is not related to erratic contamination, but pertains to silicon. The Shockley–Read–Hall generation‐recombination mechanism (leading to the Sah–Noyce–Shockley theory of thep‐njunction) is proved to give an unsatisfactory description of the almost ideal diode.

ISSN:0021-8979    

DOI:10.1063/1.342098

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

The objective of this paper is to provide a theoretical analysis regarding excess current in an Esaki junction. The analysis makes use of the crystal momentum representation, and takes into account, among other things, three‐dimensional energy‐momentum conservations. The treatment is more general than similar studies reported earlier, and is likely to explain the experimental data better than earlier studies.

ISSN:0021-8979    

DOI:10.1063/1.342101

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

The electrical performance of Be‐doped,p‐p+GaAs homojunction barriers is characterized and analyzed. The results of the analysis show that minority‐carrier electrons, at 300 K, have a mobility of 4760 cm2/V s at a hole concentration of 2.3×1016cm−3, and that the effective recombination velocity for these homojunction barriers is about 6×104cm/s. We present evidence that this unexpectedly high recombination velocity is a consequence of an effective reduction in band gap due to the heavy impurity doping. The effective band‐gap shrinkage in this Be‐doped material grown by molecular‐beam epitaxy appears to be comparable to that already observed for Zn‐doped GaAs grown by metalorganic chemical vapor deposition. This work demonstrates that so‐called band‐gap narrowing effects significantly influence the electrical performance of GaAs devices.

ISSN:0021-8979    

DOI:10.1063/1.342102

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

The drift velocity of hot electrons in ann‐GaAs quantum well is calculated with the exact distribution function deduced from the Boltzmann integral equation. The interaction of the charge carriers with surface and bulk polar optical phonons and ionized impurities is considered in the calculation. The influence of intercarrier collisions as well as the quantum‐well width on the distribution function and on the drift velocity is analyzed systematically. The theoretical results are compared with recent experimental data deduced from pulsed Hall measurements.

ISSN:0021-8979    

DOI:10.1063/1.342071

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

This paper studies the thickness of siliconp‐njunction space‐charge regions at low temperature including the effects of doping‐dependent dielectric permittivity &egr;(N), which is important for heavily doped semiconductor materials because of the presence of unionized impurity atoms that are subjected to polarization. The treatment is applicable forp‐njunctions under all voltages and is not based on the conventional depletion approximation which assumes free carriers are negligible in the space‐charge region. Comparison of the present thickness model including &egr;(N) and the conventional depletion model is included.

ISSN:0021-8979    

DOI:10.1063/1.342072

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

We use a highly accurate numerical computer model to solve the problem of equilibrium barrier formation in graded Hg1−xCdxTe heterojunctions including valence‐band offsets. The present calculation is an extension of our previous work [J. Appl. Phys.62, 3267 (1987)], which incorporated physical features designed to improve upon previous calculations, but employed the common anion rule. First, we analyze and compare our results to the recent work of Oda [Infrared Phys.27, 49 (1987)] and find significant differences. Then, we make a comparison with the results of our previous work. We observe clear trends between our results with and without the valence‐band offset. Unlike Oda, we do not make general predictions with regard to the conditions needed to support the formation and growth of a barrier in the conduction band, but instead find the band profiles to be a complex function of all the junction design parameters. For the present study involving narrow gappon wide gapnheterojunctions, and the assumed: HgTe:CdTe 300‐meV valence‐band offset, the band profiles do not differ significantly from the profiles assuming the common anion rule.

ISSN:0021-8979    

DOI:10.1063/1.342073

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

Thin‐film metal‐insulator‐semiconductor structures have been prepared by deposition ofn‐type indium telluride films on partially oxidized aluminum layers. An analysis of the current‐voltage characteristics indicates the current transfer mechanism in these structures to be of the Schottky thermionic emission type in low field and space‐charge limited at high fields. The barrier height presented to the conduction electrons in such structures has also been calculated from the temperature dependence of theI‐Vcharacteristics.

ISSN:0021-8979    

DOI:10.1063/1.342074

出版商:AIP    

年代:1988

数据来源: AIP