[18p-B31-1~16] 15.3 III-V-group epitaxial crystals, Fundamentals of epitaxy

[18p-B31-1] Epitaxial GaAs Lift Off from Si(111) via 2D-In₂Se₃

〇Nobuaki Kojima¹, Yu-Cian Wang¹, Kei Kawakatsu¹, Akio Yamamoto¹, Yoshio Ohshita¹, Masafumi Yamaguchi¹ (1.Toyota Tech. Inst.)

Keywords:epitaxial lift-off, epitaxial growth, III-V thin film solar cell

Epitaxial lift off (ELO) of III-V materials from semiconductor substrate is one of the key technologies to achieve low cost and high-efficiency III-V solar cells. We will report novel high-speed ELO technique of GaAs epitaxial film from 2-inch Si(111) substrate via 2D-In₂Se₃ layer. Double layers of In₂Se₃ and GaAs were grown by molecular beam epitaxy (MBE). The GaAs layer was peeled from Si substrate onto flexible PMMA sheet by the applying thermal stress induced by liquid nitrogen dipping. This ELO technique enables the dramatically cost reduction of thin film flexible III-V solar cells than the usual selective etching technique by aqueous acid.