Direct observation of spinodal decomposition phenomena in InAlN alloys during in-situ STEM heating

Pališaitis, Justinas; Hsiao, Ching‐Lien; Hultman, Lars; Birch, Jens; Persson, Per

doi:10.1038/srep44390

Cited by 23 publications

(18 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our predicted separation zone for InAlN alloy is between 8 and 82% of indium, which is in agreement with the experimental data presented in refs. . Indeed, no phase separation zone exists for AlGaN, the critical temperature is 177 K. From these results, which are in excellent agreement with the experimental data, we can use the calculated interaction parameters of the ternary alloys to construct the phase diagrams for quaternary alloys.…”

Section: Resultssupporting

confidence: 80%

A Theoretical Investigation of the Miscibility and Structural Properties of In_xAl_yGa_1−x−yN Alloys

Mohamad

Béré

Hounkpati

et al. 2018

Physica Status Solidi (b)

View full text Add to dashboard Cite

In this theoretical investigation of the miscibility in quaternary alloys, we stay in the regular solution model and determine the interaction parameters from the enthalpy of mixing calculated using a modified Stillinger–Weber (SW) potential for III‐nitride ternary alloys. From our calculation, the values of the interaction parameters are 6.605, 10.523, and 0.677 kcal mol−1, respectively, for InGaN, InAlN, and AlGaN at x = 0.5 (where x is the In and Al fraction in InGaN, InAlN, and AlGaN, respectively). These values are in good agreement with those predicted by the improved delta lattice parameter (DLP) model for nitride ternary alloys. To determine the unstable regions characterized by the spinodal decomposition of the quaternary alloy InxAlyGa1−x−yN, we consider the composition ranges of 0.06 ≤ x ≤ 1 and 0 ≤ y ≤ 0.94. Our calculations show that the phase separation temperature increases with the increase of indium concentration. For In concentration lower than 9.4%, the quaternary alloy is miscible independent of the Al and Ga compositions in the usual growth temperature range for metalorganic vapor phase epitaxy.

show abstract

Section: Resultssupporting

confidence: 80%

A Theoretical Investigation of the Miscibility and Structural Properties of In_xAl_yGa_1−x−yN Alloys

Mohamad

Béré

Hounkpati

et al. 2018

Physica Status Solidi (b)

View full text Add to dashboard Cite

show abstract

“…[8][9][10][11][12][13] The same can be said for In-AlN as well. 14,15 The situation is even worse in the case of BGaN and BAlN where the boron incorporation is typically less than 3%. 15,[105][106][107] The electronic properties of the above mentioned materials have been previously investigated.…”

Section: Discussionmentioning

confidence: 99%

“…6,7 Specifically, a phase separation in InGaN and InAlN alloys has been observed in a wide range of compositions. [8][9][10][11][12][13][14][15] The spinodal decomposition occurring in InGaN (InAlN) is driven by the internal strain due to the excessive lattice mismatch between InN and GaN (AlN). On the other hand, the critical temperature for the appearance of the miscibility gap in the case of the AlGaN system has been shown to be much lower than the growth temperature.…”

Section: Introductionmentioning

confidence: 99%

First-principles study of the impact of the atomic configuration on the electronic properties of AlxGa1−xN alloys

2019

View full text Add to dashboard Cite

We employ first principles calculations in the formalism of standard and hybrid density functional theory to study the electronic and structural properties of wurtzite AlxGa1−xN alloys. We address the discrepancies observed in literature regarding essential electronic properties of these alloys and we investigate the dependence of these properties on the atomic ordering and composition. We show that the bowing parameter is significantly affected by the atomic ordering, ranging from zero to strong downward bowing. The effects of atomic ordering of the alloys on their band offset with respect to the pure phases is also investigated. Finally, using the effective band structure approach, we study the electronic band structure of the random alloys.

show abstract

“…Moreover, the HRTEM observations in Fig. 6e, f reveal that spinodal decomposition begins at interfaces between the Zn-Sb and Bi-Sb grain boundaries, indicating that the spinodal decomposition has a surface-directed component 27 .…”

Section: Properties and Microstructure Of Bi-doped Zn 2 Sb 3 Thin Filmsmentioning

confidence: 92%

Conversion of p–n conduction type by spinodal decomposition in Zn-Sb-Bi phase-change alloys

et al. 2020

View full text Add to dashboard Cite

Phase-change films with multiple resistance levels are promising for increasing the storage density in phase-change memory technology. Diffusion-dominated Zn 2 Sb 3 films undergo transitions across three states, from high through intermediate to low resistance, upon annealing. The properties of the Zn 2 Sb 3 material can be further optimized by doping with Bi. Based on scanning transmission electron microscopy combined with electrical transport measurements, at a particular Bi concentration, the conduction of Zn-Sb-Bi compounds changes from p-to n-type, originating from spinodal decomposition. Simultaneously, the change in the temperature coefficient of resistivity shows a metal-toinsulator transition. Further analysis of microstructure characteristics reveals that the distribution of the Bi-Sb phase may be the origin of the driving force for the p-n conduction and metal-to-insulator transitions and therefore may provide us with another way to improve multilevel data storage. Moreover, the Bi doping promotes the thermoelectric properties of the studied alloys, leading to higher values of the power factor compared to known reported structures. The present study sheds valuable light on the spinodal decomposition process caused by Bi doping, which can also occur in a wide variety of chalcogenide-based phase-change materials. In addition, the study provides a new strategy for realizing novel p-n heterostructures for multilevel data storage and thermoelectric applications.

show abstract

Direct observation of spinodal decomposition phenomena in InAlN alloys during in-situ STEM heating

Cited by 23 publications

References 29 publications

A Theoretical Investigation of the Miscibility and Structural Properties of In_xAl_yGa_1−x−yN Alloys

A Theoretical Investigation of the Miscibility and Structural Properties of In_xAl_yGa_1−x−yN Alloys

First-principles study of the impact of the atomic configuration on the electronic properties of AlxGa1−xN alloys

Conversion of p–n conduction type by spinodal decomposition in Zn-Sb-Bi phase-change alloys

Contact Info

Product

Resources

About

Direct observation of spinodal decomposition phenomena in InAlN alloys during in-situ STEM heating

Cited by 23 publications

References 29 publications

A Theoretical Investigation of the Miscibility and Structural Properties of InxAlyGa1−x−yN Alloys

A Theoretical Investigation of the Miscibility and Structural Properties of InxAlyGa1−x−yN Alloys

First-principles study of the impact of the atomic configuration on the electronic properties of AlxGa1−xN alloys

Conversion of p–n conduction type by spinodal decomposition in Zn-Sb-Bi phase-change alloys

Contact Info

Product

Resources

About

A Theoretical Investigation of the Miscibility and Structural Properties of In_xAl_yGa_1−x−yN Alloys

A Theoretical Investigation of the Miscibility and Structural Properties of In_xAl_yGa_1−x−yN Alloys