[17a-PA02-1~11] 9.2 Nanoparticles, Nanowires and Nanosheets

▲ [17a-PA02-8] Top-down Fabrication of Ge/Si core/shell Nanowire Channels for Vertical-type Field Effect Transistors

〇Chao Le^1,2, Yonglie Sun¹, Wipakorn Jevasuwan¹, Naoki Fukata^1,2 (1.NIMS, 2.Univ. of Tsukuba)

Keywords:nanowire, germanium, silicon

Nowadays Field Effect Transistors (FETs) has a significantly wide range of application in electronic devices. In this case, higher performance types of FETs are required. The structure of the FET and using materials, are very important. For the structure, scaling the size and increase the number of gates can significantly improve the performance. However, dopant impurities affect the carrier mobility. To solve problems caused by scaling, core/shell structure nanowires (NWs) was appeared to our sight. We decided to use undoped Ge as a core and Boron-doped Si as a shell. The mobility of Ge is greater than Si, so we chose Ge as the core. On the other hand, there are energy band-offsets between Ge and Si and the trap-shaped structure will be formed in the heterojunction. Depending on the Fermi level position, hole gas can be accumulated in the quantum well.
In this study, we focused on top-down method to fabricate vertical type Ge/Si core/shell NWs and demonstrate hole gas accumulation in the NW as evidence of successful fabrication.