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Title: Study of a MHEMT heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel MBE-grown on a GaAs substrate using reciprocal space mapping

Abstract

The crystallographic characteristics of the design elements of a metamorphic high-electron-mobility (MHEMT) heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel are determined based on reciprocal space mapping. The heterostructure is grown by molecular beam epitaxy on the vicinal surface of a GaAs substrate with a deviation angle from the (001) plane of 2° and consists of a stepped metamorphic buffer containing six layers including an inverse step, a high-temperature buffer layer with constant composition, and active HEMT layers. The InAs content in the layers of the metamorphic buffer is varied from 0.1 to 0.48. Reciprocal space maps are constructed for the (004) symmetric reflection and (224)+ asymmetric reflection. It is found that the heterostructure layers are characterized both by a tilt angle relative to the plane of the (001) substrate and a rotation angle around the [001] axis. The tilt angle of the layer increases as the InAs concentration in the layer increases. It is shown that a high-temperature buffer layer of constant composition has the largest degree of relaxation compared with all other layers of the heterostructure.

Authors:
;  [1];  [2];  [1]
  1. Russian Academy of Sciences, Institute of Ultrahigh Frequency Semiconductor Electronics (Russian Federation)
  2. Federal Agency on Technical Regulating and Metrology, Center for Study of Surface and Vacuum Properties (Russian Federation)
Publication Date:
OSTI Identifier:
22469818
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 49; Journal Issue: 8; Other Information: Copyright (c) 2015 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; CRYSTAL STRUCTURE; ELECTRON MOBILITY; GALLIUM ARSENIDES; HETEROJUNCTIONS; INDIUM ARSENIDES; LAYERS; MAPPING; MOLECULAR BEAM EPITAXY; REFLECTION; RELAXATION; SUBSTRATES; SURFACES

Citation Formats

Aleshin, A. N., E-mail: a.n.aleshin@mail.ru, Bugaev, A. S., Ermakova, M. A., and Ruban, O. A. Study of a MHEMT heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel MBE-grown on a GaAs substrate using reciprocal space mapping. United States: N. p., 2015. Web. doi:10.1134/S1063782615080035.
Aleshin, A. N., E-mail: a.n.aleshin@mail.ru, Bugaev, A. S., Ermakova, M. A., & Ruban, O. A. Study of a MHEMT heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel MBE-grown on a GaAs substrate using reciprocal space mapping. United States. doi:10.1134/S1063782615080035.
Aleshin, A. N., E-mail: a.n.aleshin@mail.ru, Bugaev, A. S., Ermakova, M. A., and Ruban, O. A. Sat . "Study of a MHEMT heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel MBE-grown on a GaAs substrate using reciprocal space mapping". United States. doi:10.1134/S1063782615080035.
@article{osti_22469818,
title = {Study of a MHEMT heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel MBE-grown on a GaAs substrate using reciprocal space mapping},
author = {Aleshin, A. N., E-mail: a.n.aleshin@mail.ru and Bugaev, A. S. and Ermakova, M. A. and Ruban, O. A.},
abstractNote = {The crystallographic characteristics of the design elements of a metamorphic high-electron-mobility (MHEMT) heterostructure with an In{sub 0.4}Ga{sub 0.6}As channel are determined based on reciprocal space mapping. The heterostructure is grown by molecular beam epitaxy on the vicinal surface of a GaAs substrate with a deviation angle from the (001) plane of 2° and consists of a stepped metamorphic buffer containing six layers including an inverse step, a high-temperature buffer layer with constant composition, and active HEMT layers. The InAs content in the layers of the metamorphic buffer is varied from 0.1 to 0.48. Reciprocal space maps are constructed for the (004) symmetric reflection and (224)+ asymmetric reflection. It is found that the heterostructure layers are characterized both by a tilt angle relative to the plane of the (001) substrate and a rotation angle around the [001] axis. The tilt angle of the layer increases as the InAs concentration in the layer increases. It is shown that a high-temperature buffer layer of constant composition has the largest degree of relaxation compared with all other layers of the heterostructure.},
doi = {10.1134/S1063782615080035},
journal = {Semiconductors},
number = 8,
volume = 49,
place = {United States},
year = {Sat Aug 15 00:00:00 EDT 2015},
month = {Sat Aug 15 00:00:00 EDT 2015}
}
  • The crystallographic parameters of elements of a metamorphic high-electron-mobility transistor (MHEMT) heterostructure with In{sub 0.4}Ga{sub 0.6}As quantum well are determined using reciprocal space mapping. The heterostructure has been grown by molecular-beam epitaxy (MBE) on the vicinal surface of a GaAs substrate with a deviation angle of 2° from the (001) plane. The structure consists of a metamorphic step-graded buffer (composed of six layers, including an inverse step), a high-temperature buffer of constant composition, and active high-electron-mobility transistor (HEMT) layers. The InAs content in the metamorphic buffer layers varies from 0.1 to 0.48. Reciprocal space mapping has been performed for themore » 004 and 224 reflections (the latter in glancing exit geometry). Based on map processing, the lateral and vertical lattice parameters of In{sub x}Ga{sub 1–x}As ternary solid solutions of variable composition have been determined. The degree of layer lattice relaxation and the compressive stress are found within the linear elasticity theory. The high-temperature buffer layer of constant composition (on which active MHEMT layers are directly formed) is shown to have the highest (close to 100%) degree of relaxation in comparison with all other heterostructure layers and a minimum compressive stress.« less
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