Table Of ContentRadio Frequency
Micromachined Switches,
Switching Networks, and
Phase Shifters
Radio Frequency
Micromachined Switches,
Switching Networks, and
Phase Shifters
Shiban Kishen Koul
Sukomal Dey
CRC Press
Taylor & Francis Group
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Library of Congress CataloginginPublication Data
Names: Koul, Shiban K., author. | Dey, Sukomal, author.
Title: Radio frequency micromachined switches, switching networks, and phase
shifters / Shiban Kishen Koul, Sukomal Dey.
Description: Boca Raton, FL : CRC Press, Taylor & Francis Group, [2019] |
Includes bibliographical references and index.
Identifiers: LCCN 2019011927| ISBN 9780815361435 (hardback ; alk. paper) |
ISBN 0815361432 (hardback ; alk. paper) | ISBN 9781351021340 (ebook) |
ISBN 1351021346 (ebook)
Subjects: LCSH: Radio frequency microelectromechanical systems. | Phase
shifters.
Classification: LCC TK7875 .K68 2019 | DDC 621.3815--dc23
LC record available at https://lccn.loc.gov/2019011927
Visit the Taylor & Francis Web site at
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To
Mansi Narain, Grace Yoo Koul, Amendra Koul, Anant Koul
and
Swapan Ranjan Dey, Pranati Dey, Nibedita Dey, Nairick Dey
Contents
Preface ...........................................................................................................................................xiii
Authors ...........................................................................................................................................xv
1. Introduction to Microelectromechanical Systems ...........................................................1
1.1 MEMS Overview ...........................................................................................................1
1.2 Transmission Line .........................................................................................................2
1.3 RF MEMS Switch...........................................................................................................5
1.4 RF MEMS Phase Shifters .............................................................................................8
1.5 Major Applications of RF MEMS Phase Shifters ....................................................10
1.6 Book Organization ......................................................................................................11
References ...............................................................................................................................12
2. Behavioral Studies of Micromachined Contact Switches ............................................15
2.1 MEMS Switch Design .................................................................................................15
2.2 Switch Model ...............................................................................................................15
2.3 Switch Design, Simulation and Measurements ......................................................17
2.3.1 Switch Profile Analysis and Mechanical Resonance ................................17
2.3.1.1 Switch Mechanical Measurements ..............................................20
2.3.2 Switch Pull-In Behavior Basics.....................................................................20
2.3.3 Dynamic Behavior of the Switch .................................................................23
2.3.3.1 Actuation/Release Voltage Measurements ................................28
2.3.3.2 Switching/Release Time Measurements ....................................28
2.3.4 Switch Contact Resistance Basics ................................................................29
2.4 Thermal Behavior of the Switch ...............................................................................31
2.4.1 Thermal Measurement ..................................................................................34
2.5 RF Power Handling ....................................................................................................34
2.5.1 RF Power Handling Measurements ............................................................38
2.6 Switch S-Parameter Analysis and Measurements .................................................39
2.7 Switch Linearity and Its Measurement ....................................................................41
2.8 Conclusion ....................................................................................................................43
References ...............................................................................................................................43
3. Single-Pole Multithrow MEMS Switching Networks ..................................................47
3.1 High Isolation Single-Pole Double-Throw (SPDT) Switch ....................................47
3.1.1 Series–Shunt Switch Design and Measurement ........................................47
3.1.2 SPDT Switch Design and Measurement .....................................................48
3.2 Single-Pole Four-Throw (SP4T) Switch Design and Measurement ......................50
3.3 Compact SPMT Switching Networks .......................................................................53
3.3.1 Single-Pole Single-Throw (SPST) Switch Design and Measurement ......53
3.3.2 Single-Pole Three-Throw (SP3T) Switch Design and Measurement ......55
3.3.3 Single-Pole Six-Throw (SP6T) Switch Design and Measurement ............56
3.3.4 Single-Pole Seven-Throw (SP7T) Switch Design and Measurement ......57
3.3.5 Single-Pole Eight-Throw (SP8T) Switch Design and Measurement .......57
3.3.6 Single-Pole Ten-Throw (SP10T) Switch Design and Measurement.........59
vii
viii C ontents
3.3.7 Single-Pole Eleven-Throw (SP11T) Switch Design and Measurement .......59
3.3.8 Single-Pole Twelve-Throw (SP12T) Switch Design and Measurement ......59
3.3.9 Single-Pole Fourteen-Throw (SP14T) Switch Design and
Measurement ..................................................................................................61
3.4 Equivalent Circuit Model of the SPMT Switch .......................................................61
3.5 Key Design Features of MEMS SPMT Switches .....................................................62
3.6 Third-Order Intermodulation Intercept Point (IIP3) Measurements of
MEMS SPMT Switches ...............................................................................................62
3.7 Conclusion ....................................................................................................................64
References ...............................................................................................................................64
4. Lateral MEMS Switches and Switching Networks .......................................................67
4.1 Design, Simulation and Measurement of the SPST Lateral Switch ....................67
4.1.1 Design of Lateral MEMS Switch ..................................................................67
4.1.2 Lateral Switch Characterization ..................................................................69
4.1.2.1 SPST Lateral Switch Characterization .........................................69
4.1.2.2 SPDT Lateral Switch Characterization ........................................70
4.1.2.3 SP3T Lateral Switch Characterization .........................................70
4.1.2.4 SP4T Lateral Switch Characterization .........................................71
4.1.2.5 SP6T and SP7T Switch Characterizations ...................................72
4.2 Conclusion ....................................................................................................................72
References ...............................................................................................................................74
5. Micromachined Microwave Phase Shifters ....................................................................77
5.1 Introduction .................................................................................................................77
5.2 Applications .................................................................................................................79
5.3 Technologies ................................................................................................................79
5.4 Theoretical Background .............................................................................................80
5.5 Classifications ..............................................................................................................82
5.5.1 Reflection-Type Phase Shifter.......................................................................82
5.5.2 Switched-Line Phase Shifter ........................................................................87
5.5.3 Loaded-Line Phase Shifters ..........................................................................89
5.5.4 Low-Pass/High-Pass Network Phase Shifter ............................................92
5.5.5 Distributed MEMS Transmission Line (DMTL) Phase Shifter ...............93
5.6 Conclusion ....................................................................................................................95
References ...............................................................................................................................97
6. Digital MEMS Switched-Line Phase Shifters ..............................................................101
6.1 Introduction ...............................................................................................................101
6.2 Switched-Line Phase Shifter Design ......................................................................101
6.3 MEMS Switch Design ...............................................................................................102
6.4 MEMS Switch Performance Analysis ....................................................................102
6.5 MEMS Primary Bit Phase Shifter Fabrication and Measurements ....................105
6.6 5-Bit Switched-Line Phase Shifters Fabrication and Measurements .................107
6.6.1 5-Bit Phase Shifter Using SW1: Phase 1 ....................................................107
6.6.2 5-Bit Phase Shifter Using SW2: Phase 2 ....................................................110
6.7 Life Cycle of 5-Bit Phase Shifters ............................................................................112
6.8 Conclusion ..................................................................................................................114
References .............................................................................................................................114
C ontents ix
7. DMTL Phase Shifter Design Using MAM Capacitors and a MEMS Bridge .........117
7.1 Introduction ...............................................................................................................117
7.2 Unit Cell Phase Shifter Design and Modeling ......................................................117
7.3 Fabrication and Measurements ...............................................................................121
7.3.1 Unit Cell Phase Shifter Measurements and Results ...............................121
7.3.2 Primary Phase Bits Measurement Results ...............................................124
7.3.3 Complete 5-Bit Phase Shifter Measurements and Results .....................125
7.4 Reliability Measurements and Results ..................................................................127
7.4.1 Reliability Measurements of the MEMS Bridge ......................................127
7.4.2 Reliability Measurements of the 5-Bit Phase Shifter ..............................129
7.5 Conclusion ..................................................................................................................130
References .............................................................................................................................130
8. Push–Pull Type of Micromachined Phase Shifters ....................................................131
8.1 Introduction ...............................................................................................................131
8.2 Operating Principle of the Push–Pull Actuator....................................................131
8.2.1 Analysis of Bridge Pull-In Voltage Using Quasistatic
Approximation .............................................................................................132
8.2.2 Analysis of the Push–Pull Actuator under Step and Modulated
Voltage Responses........................................................................................137
8.3 Modeling of the Push–Pull Bridge .........................................................................139
8.4 DMTL Unit Cell Phase Shifter Design and Modeling .........................................141
8.5 Fabrication ..................................................................................................................143
8.6 Measurements ...........................................................................................................144
8.6.1 Mechanical Measurements .........................................................................144
8.6.2 Electrical Measurements .............................................................................147
8.6.3 S-Parameter Measurements of the Unit Cell Phase Shifter ...................148
8.6.4 Measurements of the Complete Push–Pull Analog Phase Shifter .......148
8.7 Discussion of Push–Pull Bridge Performances.....................................................151
8.8 Conclusion ..................................................................................................................151
References .............................................................................................................................152
9. Reconfigurable Micromachined Phase Shifters Using Push–Pull Actuators ........155
9.1 Introduction ...............................................................................................................155
9.2 Design and Analysis of a Phase Shifter Using a Push–Pull Actuator ..............156
9.3 Design and Analysis of the Push–Pull Voltages and a Travel Range................157
9.4 Design of Primary Cell Phase Shifters ..................................................................160
9.5 Design of Complete 5-Bit Phase Shifter .................................................................162
9.6 Fabrication Process Details ......................................................................................164
9.7 Measurements of the Push–Pull Actuator and Primary Phase Bits ..................166
9.7.1 Mechanical Measurement of the Push–Pull Actuator ...........................166
9.7.2 V , V and Capacitance Measurements ..............................................168
pull push
9.7.3 Response Time Measurements of the Push–Pull Actuator ...................169
9.7.4 S-Parameter Measurements........................................................................169
9.8 Measurements of the Complete 5-Bit Phase Shifter .............................................174
9.9 Power Handling and Reliability Measurements ..................................................175
9.10 Reliability Measurements on the 5-Bit Phase Shifter ..........................................178
9.11 Conclusion ..................................................................................................................181
References .............................................................................................................................181
