Structural properties of homoepitaxial and heteroepitaxial ZnSe-based laser structures

Heinke, H.; Behringer, Martin; Wenisch, H.; Grossmann, V.; Hommel, D.

doi:10.1016/s0022-0248(98)80123-1

Cited by 5 publications

(6 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[1][2][3][4][5] The x-ray rocking curve technique, which is a form of HRXRD, measures the sample reflecting power as a function of the angle between the sample surface and the incident x-ray beam and provides information on layer thickness, composition, and strain for epitaxial layers. When applied to simple structures such as a single heterolayer consisting of three or less elemental constituents on a known substrate, the thickness, composition and strain of the overlayer can be obtained with great accuracy simply by using basic formulations of Bragg's law.…”

Section: High-resolution X-ray and Transmission Electron Microscopic mentioning

confidence: 99%

High-resolution x-ray and transmission electron microscopic analysis of a GaInAsSb/AlGaAsSb multiple quantum well laser structure

Gray

Newell

Lester

et al. 1999

Journal of Applied Physics

View full text Add to dashboard Cite

Use of transmission electron microscopy in the characterization of GaInNAs(Sb) quantum well structures grown by molecular beam epitaxyEnhanced band-gap blueshift due to group V intermixing in InGaAsP multiple quantum well laser structures induced by low temperature grown InP High-resolution x-ray diffractometry ͑HRXRD͒ and transmission electron microscopy ͑TEM͒ are employed to characterize a quaternary III x III 1Ϫx V y V 1Ϫy AlGaAsSb/GaInAsSb multiple quantum well ͑MQW͒ heterostructure. A method for uniquely determining the chemical composition of the strained quaternary quantum well, information previously thought to be unattainable using HRXRD, is thoroughly described. The misconception that HRXRD can separately find the well and barrier thickness of a MQW from the pendellosung fringe spacing is corrected and, thus, the need for TEM is motivated. Computer simulations show that the key in finding the well composition is the intensity of the higher order satellite peaks in the diffraction pattern. For the AlGaAsSb/InGaAsSb MQWs analyzed in this work, the variation in the intensity of the third-order satellite peak is identified as a sensitive measure of the quantum well composition. Using HRXRD on an MQW semiconductor laser device layer, the ability to resolve this higher order peak and interpret the information contained in it is demonstrated for the first time.

show abstract

Section: High-resolution X-ray and Transmission Electron Microscopic mentioning

confidence: 99%

High-resolution x-ray and transmission electron microscopic analysis of a GaInAsSb/AlGaAsSb multiple quantum well laser structure

Gray

Newell

Lester

et al. 1999

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…They enable one to minimize the dislocation density by a lattice matched and consequently pseudomorphic growth. However, an ideal lattice matched growth between sulfur containing layers and an underlying substrate is hard to realize [2,8]. This results in a rather wide range of lattice mismatches found for ZnSe based laser structures.…”

Section: Strain Statementioning

confidence: 99%

“…Here the p-type layer is characterized by a strain parameter of γ = 0.92. The usually observed splitting between peaks related to the n-type and ptype doped MgZnSSe layers is attributed to the p-type doping, which is performed with a nitrogen plasma source [2].…”

Section: Defect Densitymentioning

confidence: 99%

“…However, the layer peaks in double axis scans can be broadened by structural defects as well as by fluctuations of their chemical composition. The latter are often observed in MgZnSSe layers due to the strong dependence of the sulfur incorporation on the substrate temperature [2,8]. In order to separate both effects, triple axis rocking curves through the (004) peaks of the ndoped cladding layers were performed.…”

Section: Defect Densitymentioning

confidence: 99%

“…An alternative approach for growing high-quality ZnSe based layers is the use of ZnSe substrates. However, the structural quality of the homoepitaxially grown layers is often poor [2], despite the theoretical advantages of the non-polar interface and the nearly perfect matching of thermal expansion coefficients. The remaining oxide on the substrate surface, which is responsible for the generation of dislocations, has been proposed as one reason for this [3].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Investigations of ZnSe based laser structures on ZnSe substrates by high resolution x-ray diffraction

Grossmann¹,

Heinke²,

Wenisch³

et al. 1999

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

The structural quality of homoepitaxially grown ZnSe based layers depends sensitively on the ZnSe substrate preparation prior to the growth. In this paper the consequences of an in situ hydrogen plasma cleaning of ZnSe substrates to the crystalline quality of II-VI based laser structures are discussed. The crystalline properties of the resulting laser structures are compared with those of homoepitaxially grown structures on non-hydrogen cleaned substrates as well as with the characteristics of heteroepitaxially grown lasers on GaAs. The samples were grown by molecular beam epitaxy and characterized by high-resolution x-ray diffraction. Remarkable differences in the strain state of the homoepitaxially grown samples are observed. While the structures grown on hydrogen cleaned ZnSe substrates are pseudomorphic, layers of comparable thickness and lattice mismatch on non-hydrogen cleaned substrates show clear strain relaxation. Triple axis (004) rocking curves reveal distinct differences between the three sample types investigated. According to these measurements, the in situ hydrogen plasma cleaning of ZnSe substrates results in a drastic improvement of crystalline perfection of the homoepitaxial laser structures. However, even the defect density of the optimized homoepitaxial samples exceeds that of heteroepitaxial reference lasers by two orders of magnitude as estimated from the diffuse scattered intensity.

show abstract

Blue-Green Light Emitting Diodes with New p-Contact Layers: ZnSe/BeTe

Cho

Chang

Wenisch

et al. 2000

phys. stat. sol. (a)

Self Cite

View full text Add to dashboard Cite

Wcm 2 even without annealing when the ZnSe layer thickness is 5 nm. The composition of quaternary ZnMgBeSe was determined using a ZnBeSe/ ZnMgBeSe layer structure by PL and X-ray measurements. The p-type doping property was investigated for ZnMgBeSe with different compositions, and N a ±N d drastically decreases with increasing band gap energy the same as that of the ZnMgSSe:N system. The fabricated LEDs show a strong electroluminescence under dc bias at room temperature.

show abstract

Structural properties of homoepitaxial and heteroepitaxial ZnSe-based laser structures

Cited by 5 publications

References 17 publications

High-resolution x-ray and transmission electron microscopic analysis of a GaInAsSb/AlGaAsSb multiple quantum well laser structure

High-resolution x-ray and transmission electron microscopic analysis of a GaInAsSb/AlGaAsSb multiple quantum well laser structure

Investigations of ZnSe based laser structures on ZnSe substrates by high resolution x-ray diffraction

Blue-Green Light Emitting Diodes with New p-Contact Layers: ZnSe/BeTe

Contact Info

Product

Resources

About