**7. Conclusions**

The objective is to fabricate the simulated designs using low cost fabrication processes. Considering the ease of implementation and complications of the processes involved, it is focused to fabricate only the capacitive shunt switches using a low cost, low resistivity silicon wafer as the substrate and using only four masks for the whole process. Surface micromachining process was used to fabricate these switches. During the fabrication several challenges such as residual stress of top gold film, planarization of sacrificial layer, release of top beam were encountered and are overcome. Several rounds of optimization of unit process led to the successful fabrication of these switches. Packaging the fabricated switches, was done using low temperature methods to minimize the effect of packaging on the structure. The packaging of these switches used SMAs. The packaging involved several steps such as wafer dicing, conductor screen printing on substrate, die bonding, wire bonding and hermetic sealing. The switches are packaged and hermetically sealed by using a unique method of curing and sealing using room temperature methods, in order to avoid thermally induced stress in the fragile MEMS beams of the switches. The proposed packaging methodology has passed both the shear test and the hermeticity tests. By optimizing the fabrication process to cater to batch processing and also finding methods of CMOS compatible methods, this technology will help meet the ever growing demands of wired as well as wireless communication for low loss high performance RF switches.

#### **Acknowledgements**

My sincere thanks to Dr. Premila Manohar, Professor and Head, Department of Electronics and Instrumentation, Ramaiah Institute of Technology who has encouraged me throughout the research project towards its completion and implementation. My sincere thanks to Dr. N. Sayanu Pamidhighantam, who introduced me to the beautiful world of MEMS. His discussions on the subject were highly enlightening and thought provoking. I deeply acknowledge his guidance and advice throughout this endeavor of mine. I owe a lot to Dr. K. Natarajan, former Professor and Head, Department of Telecommunication, for support during the project based on my work which led to fabrication of my devices which I thought was a distant dream.

**Author details**

**275**

Lakshmi Swaminathan

Technology, Bangalore, Karnataka, India

*RF MEMS Switch Fabrication and Packaging DOI: http://dx.doi.org/10.5772/intechopen.95003*

provided the original work is properly cited.

Department of Electronics and Communication, M.S. Ramaiah Institute of

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: lakshmi\_ramesh@msrit.edu

I think my research would have been only in the simulations stage if not for the project funded by National Program on Smart Materials and Structure (NPMASS) ADA, INDIA. This opportunity changed my perspective of my research since I was able to fabricate devices hands on in one of the best laboratories of the world.

The fabrication was carried out at the Centre for Nano Science and Engineering, IISc, Bangalore. I would like to express my deep sense of gratitude to Dr. K. N Bhat, Professor Emeritus, CeNSe, IISc, Bangalore for his time and valuable inputs during the fabrication of RF MEMS switches. With his repertoire of knowledge, he was able to guide us through difficult phases of fabrication. I also would like to thank the team at CeNSe for their co-operation throughout the project.

I owe a lot to my family who supported me in every way possible for the completion of my research work.

*RF MEMS Switch Fabrication and Packaging DOI: http://dx.doi.org/10.5772/intechopen.95003*

These connectors were soldered to the Alumina substrate using solder wire (Sn 63:

The objective is to fabricate the simulated designs using low cost fabrication processes. Considering the ease of implementation and complications of the processes involved, it is focused to fabricate only the capacitive shunt switches using a low cost, low resistivity silicon wafer as the substrate and using only four masks for the whole process. Surface micromachining process was used to fabricate these switches. During the fabrication several challenges such as residual stress of top gold film, planarization of sacrificial layer, release of top beam were encountered and are overcome. Several rounds of optimization of unit process led to the successful fabrication of these switches. Packaging the fabricated switches, was done using low temperature methods to minimize the effect of packaging on the structure. The packaging of these switches used SMAs. The packaging involved several steps such as wafer dicing, conductor screen printing on substrate, die bonding, wire bonding and hermetic sealing. The switches are packaged and hermetically sealed by using a unique method of curing and sealing using room temperature methods, in order to avoid thermally induced stress in the fragile MEMS beams of the switches. The proposed packaging methodology has passed both the shear test and the hermeticity tests. By optimizing the fabrication process to cater to batch processing and also finding methods of CMOS compatible methods, this technology will help meet the ever growing demands of wired as well as wireless communica-

My sincere thanks to Dr. Premila Manohar, Professor and Head, Department of Electronics and Instrumentation, Ramaiah Institute of Technology who has encouraged me throughout the research project towards its completion and implementation. My sincere thanks to Dr. N. Sayanu Pamidhighantam, who introduced me to the beautiful world of MEMS. His discussions on the subject were highly enlighten-

throughout this endeavor of mine. I owe a lot to Dr. K. Natarajan, former Professor and Head, Department of Telecommunication, for support during the project based on my work which led to fabrication of my devices which I thought was a distant

I think my research would have been only in the simulations stage if not for the project funded by National Program on Smart Materials and Structure (NPMASS) ADA, INDIA. This opportunity changed my perspective of my research since I was able to fabricate devices hands on in one of the best laboratories of the world.

The fabrication was carried out at the Centre for Nano Science and Engineering, IISc, Bangalore. I would like to express my deep sense of gratitude to Dr. K. N Bhat, Professor Emeritus, CeNSe, IISc, Bangalore for his time and valuable inputs during the fabrication of RF MEMS switches. With his repertoire of knowledge, he was able to guide us through difficult phases of fabrication. I also would like to thank the

I owe a lot to my family who supported me in every way possible for the

ing and thought provoking. I deeply acknowledge his guidance and advice

team at CeNSe for their co-operation throughout the project.

completion of my research work.

Pb37) as shown in **Figure 25**.

*Nanofibers - Synthesis, Properties and Applications*

tion for low loss high performance RF switches.

**Acknowledgements**

dream.

**274**

**7. Conclusions**
