陳炳煇臺灣大學：機械工程學研究所王柏諺Wang, Bo-YanBo-YanWang2007-11-282018-06-282007-11-282018-06-282006http://ntur.lib.ntu.edu.tw//handle/246246/61584The present study develops a flexible sensor for detecting surface wetness and the sensor transmits the information of RF signal based on RFID technique. The operation frequency of the RFID system is at 13.56MHz. The MEMS process was employed to fabricate the antenna and the sensor of RFID tag on FPCB. The shape of the RFID tag’s antenna is designed as octangle that surrounds a comb shape sensor. The transmitting information of the RFIC is changed as the surface condition of sensor changed from dry to wet and it can be observed on the screen of the digital oscilloscope. The simulations of the equivalent circuits of the RFID tag and of the S-parameter are also obtained in this study. The simulation results show the operation voltage of the RFIC, the quality factor (Q-factor) and the resonant frequency of the RFID system. The RFID tag’s antenna has an outer diameter of 2.7 cm and the quality factor of the RFID tag has a value of 10.05. The tag and the reader of RFID system are communicated through inductive coupling and the maximum transmitting range of the RF signal is about 15 cmTable of Contents Acknowledgement I Abstract II Nomenclature IV Table of Content V List of Tables VII List of Figures VIII Chapter 1 Introduction 1 1.1 Wireless remote sensor application 1 1.2 Motivation and objectives 7 1.3 Thesis organization 8 Chapter 2 Operation Principle and Design of RFID Surface Wetness Sensor 10 2.1 Operation principle for RFID surface wetness sensor 10 2.2 RFID tag circuit analysis 11 2.2.1 Inductive coupling for a powering 11 2.2.2 Resonant circuit and resonant frequency 13 2.2.3 Quality factor (Q-factor) 13 2.3 Sensing principle of a RFID surface wetness sensor 15 2.4 Design of RFID surface wetness sensor 16 2.4.1 Design of antenna 16 2.4.2 Design of comb shape sensor 17 Chapter 3 Fabrication Procedures 18 3.1 Mask design 18 3.2 Halftone printing 18 3.3 Electroplating 19 3.4 Flexible printed circuit board (FPCB) 19 3.4.1 Lithography process 20 3.4.2 Wet etching process 22 3.5 Wire bonding 23 3.6 Package process 23 3.6.1 Protection of the RFIC chip 24 3.6.2 Protection for copper antenna 24 Chapter 4 Measurement and Simulation 26 4.1 Measurement of the inductance of antenna 26 4.2 Measurement of the RF signal 27 4.2.1 Experimental apparatus 27 4.2.2 Coding in the data of RF signal 28 4.2.3 Measured result 28 4.3 Simulation of the equivalent circuits of RFID tag 29 4.4 Simulation of the electromagnetic wave 30 Chapter 5 Conclusions and Future Prospects 32 References 735402318 bytesapplication/pdfen-US可撓性感測器表面濕潤感測器射頻身分識別被動式標籤電感耦合13.56MHz軟性印刷電路板flexible sensorsurface wetnessRFIDpassive taginductive coupling13.56 MHzFPCBthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/61584/1/ntu-95-R93522109-1.pdf