A 1 × 2 Taper Slot Antenna Array with Flip-Chip Interconnect via Glass-IPD Technology for 60 GHz Radar Sensors

A low cost, broadband and compact antenna in package solution (AiP) is proposed for 60 GHz low-power radar sensor applications. Following a glass integrated passive device (Glass-IPD) manufacturing process, a compact low cost taper slot antenna (TSA) is designed on a substrate with a thickness beyond Yngvesson's range. To realize high gain and front-to-back ratio, the antenna is optimized by introducing a truncated ground. A 1 × 2 antenna array prototype is realized with a dummy transmission line chip in the dimension of 5 × 7.4 mm². Including the flip chip interconnect, the measured results demonstrate a 10 dB impedance bandwidth of 47.2 &tild; 67 GHz. The calculated gain is higher than 6.5 dBi in the end-fire direction over the entire 60 GHz band. Based on a physical RLC equivalent circuit, by co-design of the antenna with solder balls, the flip chip interconnect is compensated with a passive network. For the compensation network, its working bandwidth is from 0.1 to 67 GHz, while its insertion loss at 60 GHz is less than 0.2 dB.