臺灣博碩士論文加值系統

由於電晶體開關在高頻系統效率極低，應用微機電系統於高頻射頻系統是近年來的一個趨勢。國家晶片系統設計中心也目前提供一套微機電製程技術，可以整合微機電系統於半導體電路之中。本文旨在使用這一套新的製成技術，去作一個可以應用於高頻的微機電開關。並且設計一個控制開關的電路，來探討蝕刻基版是否會對電路造成影響。
在本論文中實現的晶片用的是TSMC 0.18μm CMOS製成與MEMS後製程，晶片相對於傳統CMOS製程多出一層RLS光罩作為後製程蝕刻使用。目前的CMOS MEMS製程技術尚不成熟，蝕刻技術只能掏空基版部分，使上方金屬層與SiO2層懸浮。金屬材質只能選擇鋁或金，選擇性相比起傳統MEMS製程較少。目標是在CMOS MEMS的蝕刻限制下，嘗試去設計一個適合應用在RF系統的開關。

Because CMOS switch has low efficiencies in high frequency system, the application of MEMS switch in high frequency system is the trend in the recent years. CIC offers a new CMOS MEMS technology now, the MEMS structure can be combined with the electronic circuit by this process. The thesis presents the MEMS switch is the design of the new process and application for the high frequency system. The electronic circuit is combined with the chip, and then discussed the etching of substrate how to affect the electronic circuit.
The circuit is fabricated by TSMC 0.18μm CMOS process with the MEMS post - process. The chip has an extra RLS mask compare to the traditional CMOS process. The CMOS MEMS is imperfect now. The etching can only hollow out the substrate and let the metal and the SiO2 structure to float. And the material of metal has only Aluminum and Gold. The choice of design in CMOS MEMS is less than traditional MEMS process. The aim is trying to design a CMOS MEMS switch that is limited by the etching and application for RF system.

Abstract (Chinese)…………………………………………………...I
Abstract (English)…………………………………………………..II
Acknowledgements………………………………………………...III
Contents…………………………………………………………….IV
Table Captions……………………………………………………...VI
Figure Captions…………………………………………………..VIII
Chapter 1 Introduction……….……………………………………..1
1.1 Motivation…………………………………..........................................1
1.2 Development of MEMS Switch…...…………………………..............3
1.3 CMOS MEMS Technology…………………………………………...4
1.4 Organization…………………………………………………...............6
Chapter 2 Fundamental of MEMS Switch……................................7
2.1 The Pull In Voltage of MEMS Switch…..…………………………….7
2.2 The Resonant Frequency……………………………………………...8
2.3 The Operation Time…...……………………………………................8
2.4 The Advantages of MEMS Switch……………………………............8
2.5 The Lateral MEMS Switch……………………………………............9
2.6 The Purposed MEMS Switch………………………………………..10
Chapter 3 Design of the MEMS Switch and the Charge Pump…………………………………………………….12
3.1 Considerations of the MEMS Switch………………………………..12
3.2 Structure of the MEMS Switch………………………………............13
3.3 Structure of the Charge Pump………………………………..............16
Chapter 4 Simulation of the MEMES Switch and the Charge Pump……………………………………………….........19
4.1 Simulation of the MEMS Switch……………………………….........19
4.2 Simulation of the Operation Time…………………………………...21
4.3 Simulation of the Resonant Frequency………………………………22
4.4 Simulation of the Isolation…………………..………………………23
4.5 Simulation of the Charge Pump……………………………………...24
4.6 Simulation Results of the Circuit…………………………………….25
4.7 Control Signal of the Charge Pump………………………………….26
Chapter 5 Chip Implementation…………………………………..29
5.1 Layout of the MEMS Switch………………………………………...29
5.2 Measurement of the Circuit…………………………………….........30
5.3 Chip Photo…………………………………………………………...31
Chapter 6 Conclusions and Future Work………………………...33
6.1 Conclusions…………………………………………………..……...33
6.2 Future Work…………………………………………………….........33
Reference……………………………………………………............35

Reference
[1] Gabriel M. Rebeiz, Jeremy B. Muldavin ,“RF MEMS Switches and Switch Circuit” Microwave Magazine, IEEE Vol2 Page:59-71Dec. 2001
[2] D. S. Hong, “Low Operating Voltage and Short Settling Time CMOS Charge Pump for MEMS Applications”, IEEE ISCAS, 2003, Vol. 5, pp. 281-284.
[3] J. Wu and K. Chang, “MOS Charge Pumps for Low-Voltage Operation,” IEEE J. Solid-State Circuits, vol. 33, no. 4, pp. 592-597, April 1998.