Investigation of directionally solidified InGaSb ternary alloys from Ga and Sb faces of GaSb(111) under prolonged microgravity at the International Space Station

Velu Nirmal Kumar; Mukannan Arivanandhan; Govindasamy Rajesh; Tadanobu Koyama; Yoshimi Momose; Kaoruho Sakata; Tetsuo Ozawa; Yasunori Okano; Yuko Inatomi; Yasuhiro Hayakawa

doi:10.1038/npjmgrav.2016.26

Investigation of directionally solidified InGaSb ternary alloys from Ga and Sb faces of GaSb(111) under prolonged microgravity at the International Space Station

NPJ Microgravity. 2016 Jul 21:2:16026. doi: 10.1038/npjmgrav.2016.26. eCollection 2016.

Authors

Velu Nirmal Kumar^{1

2}, Mukannan Arivanandhan³, Govindasamy Rajesh¹, Tadanobu Koyama¹, Yoshimi Momose¹, Kaoruho Sakata⁴, Tetsuo Ozawa⁵, Yasunori Okano^{1

6

7}, Yuko Inatomi^{7

8}, Yasuhiro Hayakawa¹

Affiliations

¹ Research Institute of Electronics, Shizuoka University, Hamamatsu, Japan.
² Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Japan.
³ Centre for Nanoscience and Technology, Anna University, Chennai, India.
⁴ Department of Chemical System Engineering, University of Tokyo, Chiba, Japan.
⁵ Department of Electrical Engineering, Shizuoka Institute of Science and Technology, Shizuoka, Japan.
⁶ Graduate School of Engineering Science, Osaka University, Osaka, Japan.
⁷ Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
⁸ School of Physical Sciences, SOKENDAI (The Graduate University for Advanced Studies), Kanagawa, Japan.

Abstract

InGaSb ternary alloys were grown from GaSb (111)A and B faces (Ga and Sb faces) under microgravity conditions on board the International Space Station by a vertical gradient freezing method. The dissolution process of the Ga and Sb faces of GaSb and orientation-dependent growth properties of InGaSb were analysed. The dissolution of GaSb(111)B was greater than that of (111)A, which was found from the remaining undissolved seed and feed crystals. The higher dissolution of the Sb face was explained based on the number of atoms at that face, and its bonding with the next atomic layer. The growth interface shape was almost flat in both cases. The indium composition in both InGaSb samples was uniform in the radial direction and it gradually decreased along the growth direction because of segregation. The growth rate of InGaSb from GaSb (111)B was found to be higher than that of GaSb (111)A because of the higher dissolution of GaSb (111)B.