A77 GHz on-chip dipole antenna with etched silicon substrate

In this paper, a 77 GHz microstrip dipole antenna is integrated on a layered 11.4 m SiO2 and a silicon substrate with thickness of 670 m. The unbalanced microstrip line is balanced by using a lumped LC circuit balun to feed both of the dipole arms. To decrease the substrate loss and hence increase the antenna gain, Localized Backside Etch (LBE) module offered by IHP is utilized to etch the area under the dipole antenna. For mechanical robustness, two walls of silicon substrate are left at the end of the dipole arms inside the etched area. The simulation results show a 3.2 dBi gain and 15 GHz bandwidth at 77 GHz.