Research On FBAR And Its Oscillator

With the development of wireless telecommunication, the system is advancing to be small, integrated and low power consumption. As a radio frequency device with excellent performance, Film Bulk Acoustic Resonator has the advantages of small size, high Q value, high working frequency, high power-handling capacity and the compatibility with semiconductor process. Compared with the traditional devices such as SAW, FBAR has more excellent function, which leads it to be the research hot spot both in China and abroad.This paper has research on FBAR and its application, including four aspects:the technological process of FBAR and its manufacturing, FBAR module and the approach to calculate intrinsic Q value, research on FBAR tunable filter and its temperature compensation, and FBAR oscillator. The main research is showing below:1. Based on the typical process, we design and draw the layout of FBAR, which has been taped out. After the analysis and summary of the problem, we improve the structure of FBAR, and then did the second taping-out. The test result, which shows FBAR works at the frequency between 1.2GHz and 1.91 GHz with the maximum Q value of 1350, demonstrates a great advancing.2. We analyse several typical FBAR modules. Based on PMBVD module, we creat an approach to calculate intrinsic Q value of FBAR by eliminating the influence of parasitic component, which improve the simulation accuracy when it is applied to circuit design.3. We present a technical method of FBAR tunable filter, design a topological structure and have a simulation to verificate it. Meanwhile, an approach using Whiston bridge and varactor to have temperature compensation on FBAR and a new FBAR structure to realize high-power compacity are also mentioned.4. Based on SMIC 0.18 process, we design a Collpits FBAR oscillator. The post-simulation result shows oscillator works at 1.867GHz with the phase noise of -140dBc/Hz@1MHz. Now the chip is being tapped out in SMIC.