Electrical Characterization of pure Boron-on-Germanium pin Diodes
L. Gebert, D. Schwarz, A. Elsayed, und J. Schulze. 2019 42nd International Convention on Information and Communication Technology, Electronics and Microelectronics (MIPRO), Seite 13-18. (Mai 2019)
Pure Boron on Germanium deposition was successfully performed using Molecular Beam Epitaxy to form ultra-shallow pin diodes. In order to form the pure Boron on Germanium heterojunction, a 100 nm thick highly Antimony doped Germanium layer was grown on a highly Arsenic doped Silicon(001) wafer by using Molecular Beam Epitaxy. Afterwards, a 5 min annealing step at 830 °C is performed to form a virtual, defect-less Germanium substrate. Growth is then continued with 300 nm of intrinsic Germanium layer. Finally, a few nanometers of Boron were deposited at a temperature of 400 °C. A maximum Boron deposition temperature of 400 °C allows the transfer of this technology to a Back End-of-Line process. A Complementary Metal-Oxide-Semiconductor-compatible fabrication process was utilized afterwards to fabricate single mesa diodes out of the grown layer stacks. The diodes show high ideality, low series resistance and low dark currents.