Reporter :You.Peng.yuang 1 Date:2014/10/21 The Design of Flexible CO 2 Sensor based on the SAW Device MOST M

2 Outline 1. Introduction 2. Purpose 3. Experimental Methods 4. Results and Discussions 5. Conclusions

3 Introduction SAW sensors Touch panel SAW filter

4 Purpose The optimal crystallization of ZnO property can be created a carbon dioxide sensor by sol- gel technology and inkjet technology.

5 The principle of SAW device A surface acoustic wave (SAW) is an acoustic wave traveling along the surface of a material exhibiting elasticity. principle of SAW device

6 SAW substrate SubstrateRigid substrateFlexible substrate AdvantageThe wave is stable Lightweight and Thin high temperature operating condition Applies to non-planar occasions DisadvantageDon’t bendDifficult to manufacture. low temperature operating condition

7 Experimental Methods Experimental Procedure (ZnO thin film by sol-gel method) Step1 Step2 Step3 Solution preparation Surface modification Spin coating Hot plateHigh-temperature furnace XRD SEM Vector network analyzer

8 Experimental Procedure Ethanol Glycol Zinc acetate TEA 8.75ml 6.25ml g ml Spin Coating: 400 rpm Bake: 20 minute Annealing: 250 ℃ TEA ( Triethanolamine)

9 Experimental Procedure ZnO thin film IDT (Integrated Device Technology)

10 Experimental Methods Experimental Procedure (The carbon dioxide Sensors measure) CO 2 Air S

11 Results and Discussions The response of carbon dioxide decreases from MHZ to MHZ

This study proves that the response of CO 2 sensor based on the flexible SAW device is observed. Therefore, the flexible SAW device based on the ZnO film is available on the realistic product. The advantage of this product is low cost, easy fabrication, and the robust response of this flexible SAW device will challenge its usefulness. 12Conclusions

13 Thanks for your attention !