Zhuang Xuefeng, Ergun Arif S, Huang Yongli, Wygant Ira O, Oralkan Omer, Khuri-Yakub Butrus T
Edward L. Ginzton Laboratory, Stanford University, Stanford, CA 94305 Email:
Sens Actuators A Phys. 2007 Jul 20;138(1):221-229. doi: 10.1016/j.sna.2007.04.008.
This paper presents a method to provide electrical connection to a 2D capacitive micromachined ultrasonic transducer (CMUT) array. The interconnects are processed after the CMUTs are fabricated on the front side of a silicon wafer. Connections to array elements are made from the back side of the substrate via highly conductive silicon pillars that result from a deep reactive ion etching (DRIE) process. Flip-chip bonding is used to integrate the CMUT array with an integrated circuit (IC) that comprises the front-end circuits for the transducer and provides mechanical support for the trench-isolated array elements. Design, fabrication process and characterization results are presented. The advantages when compared to other through-wafer interconnect techniques are discussed.
本文提出了一种用于二维电容式微机械超声换能器（CMUT）阵列提供电连接的方法。在硅晶圆正面制造好CMUT之后，再对互连进行处理。通过深反应离子刻蚀（DRIE）工艺形成的高导电硅柱从衬底背面与阵列元件进行连接。倒装芯片键合用于将CMUT阵列与集成电路（IC）集成，该集成电路包括换能器的前端电路，并为沟槽隔离的阵列元件提供机械支撑。文中给出了设计、制造工艺及表征结果。并讨论了与其他穿通晶圆互连技术相比的优势。
