(Invited) High-Mobility Ge on Insulator (GOI) by SiGe Mixing-Triggered Rapid-Melting-Growth

INTRODUCTION In order to break through the scaling limit of the transistor performance, research and development of new functional devices which enable ultrahigh speed operation, ultralow power dissipation, and multi-functional operation are strongly required. In line with this, group IV-based heterostructure technologies have been widely developed in a quarter century [1]. The high quality Ge layers on insulators (GOI) are promising materials for this purpose. High-speed Ge-channel thin film transistors (TFTs) are essential devices to realize system-in-displays and threedimensional (3-D) large scale integrated circuits (LSIs). Moreover, GOI structures are also important as channel materials of spintransistors and virtual substrates of directband gap materials with optical functions to create multifunctional 3-D LSIs [2]. In line with this, we have been developing SiGe mixing triggered liquid-phase epitaxy (LPE) [3]. This achieves high-mobility Ge single crystals on transparent insulating substrates [4]. Present paper reviews our recent progress in this novel growth technique [3-6].