In this study, we performed epitaxial layer lift-off (ELO) of AlAs0.37Sb0.63 layer toward realizing AlAs0.37Sb0.63/In0.75Ga0.25As systems on SiO2. This will enable high optical confinement in the AlAs0.37Sb0.63/In0.75Ga0.25As systems to be achieved owing to the large refractive index contrast (Delta n similar to 1.6). ELO consists of two processes: the first is adhesive wafer bonding using positive photoresist and the second is two-step selective wet etching. Metamorphic molecular beam epitaxy was used to grow selective etching layers between the substrate and the AlAs0.37Sb0.63. We confirmed that the metamorphic growth did not degrade the crystal quality and ELO was successful. Therefore, ELO improves optical confinement of AlAs0.37Sb0.63 and will be able to improve performance of all optical intersubband switches using the AlAs0.37Sb0.63/In0.75Ga0.25As systems. (c) 2006 Elsevier B.V. All rights reserved.