Wideband 60GHz on-chip antenna with an artificial magnetic conductor

A wideband 60-GHz on-chip antenna fabricated with a 0.18um CMOS process with an artificial magnetic conductor (AMC) is presented. A shield plane is patterned to create mesh and inserted between the on-chip antenna and the grounded lossy CMOS substrate. With this arrangement, a frequency selective surface is produced and the meshed shield plane provides high wave impedance over a certain bandwidth around 60 GHz. Meanwhile, the meshed shield plane behaves as an AMC and the reflected wave is in phase with the incident wave. Therefore, the loss induced by the CMOS substrate can be minimized. Both the AMC and the patch antenna are optimized to deliver a wideband operation covering 56-66 GHz. The size of the on-chip antenna including the AMC is 1.55mm by 1.55mm. Compared with the conventional on-chip antenna having a typical gain of -10dBi to -8dBi, the proposed on-chip antenna with an AMC can offer a gain of -2.5dBi to -1.5 dBi in the band. Measurement has verified the prediction.