Design Of 3D Integrated 60GHz Antenna-on-chip

Electromagnetic wave is radiated to or received from free space by antenna. The large frequency range of analog signal on antenna is processed by radio frequency integrated circuits. Base band integrated circuits are occupied to process low frequency digital signal and analog signal. Through the cooperation of radio frequency IC, base band IC and antenna, a variety of functions can be achieved. All of them are important components of a wireless communication system. In this information age, wireless communication devices are used widely. Achieving portability and multifunction of the communication system is important and significant. For this purpose, antennas should be packaged integrated with integrated circuit chips 。 Antenna-on-Chip(Ao C) technology provides a solution for antenna-chip integrated packaging. By chip processing technology, antenna and radio frequency integrated circuits can be fabricated in a single chip, which is helpful to reduce the equipment size and improve transmission performance. With the help of TSV, the latest 3D-packaging technology, chip containing radio frequency IC and antenna can be integrated with base band IC and realize high speed interconnection. This can significantly improve space utilization and achieve wireless communication system of miniaturization and high integration density.In this paper, Ao C is designed assuming standard SMIC 0.18μm CMOS technology. The integration between Ao C and radio frequency IC in a single chip and its 3D-integration packaging with base band chip is also studied.In the beginning, a planar triangular monopole antenna is designed based on planar monopole antenna theory. This antenna is fabricated in the top metal layer of CMOS technology and fed by CPW to reduce transmission loss. Artificial magnetic conductor(AMC) is inserted between antenna and lossy silicon substrate as a shield to reflect electromagnetic wave back without phase shift. On one hand, it can effectively prevent a part of electromagnetic wave into the lossy substrate. On the other hand, the reflect wave cooperate with the incident wave can enhance the total electromagnetic wave radiate to free space. Consequently, the proposed antenna on-chip can achieve a higher radiation gain.Then, the influence between antenna on-chip and the radio frequency IC on the single chip is studied with emphasis on coefficient between antennas and interconnect. This can give guidance for placing and routing. Finally, antenna-chips wireless communication system is realized through TSV technology. Besides, the TSV structure is used to realize electromagnetism isolation. The 3D wireless communication system is modeled simulated in Ansoft HFSS software. The total system is composed of two chips, the chip above contains antenna and radio frequency IC, the chip on the bottom is base band IC. This system has a size of 960μm×1600μm×517.6μm, which is appropriate for portable devices. It is based on standard CMOS technology, which means it can be fabricated in low cost, normalization, high precision and high reliability. Simulation results show that the antenna resonant at 60GHz。Its impedance band covers 13 GHz from 56 GHz to 69 GHz. The gain can reaches as large as 2d B. It can be used in 60 GHz high speed wireless transmission, such as the next generation WIFI or full high definition video transmission device.