A60-GHz double-Y balun-fed exponential tapered slot Vivaldi antenna-on-chip (AOC) is designed using standard 0.18μm six metal-layer CMOS technology. A double-Y balun feeding structure is used to make transition from coplanar to slot line. Three methods are developed for improving antenna radiation properties. First, an impeding longitudinal rectangular slits on the backed edge of the Vivaldi antenna are used to enhance the gain. Second, loading circular metal-strips are used as additional director into the slot area of Vivaldi antenna on M6. Finally, a planar arc reflector is used to inhibit the back lobe, contributing to the enhancement of gain and efficiency. The overall antenna size is very compact and equal to 700um × 940μm. The influence of the antenna position on the radiation properties is also studied. The proposed antenna offers a simulated peak gain and a radiation efficiency of-1.9 dBi and 24%, respectively.