Ⅰ. Introduction 1 1.1 Motivation 1 1.1.1 Introduction of Physical Unclonable Function 1 1.1.2 PUF Evaluation and Comparison method 2 1.1.3 Sol-Gel Coating 4 1.1.4 Research goal 5 Ⅱ. Methods 7 2.1 Fabrication process 7 2.1.1 Sol-gel Coating process 7 2.1.2 MIM Capacitors with and without Y2O3 film 9 2.1.3 IGZO TFTs with and without Y2O3 film 12 2.2 Measurement 14 2.2.1 Capacitance measurements 14 2.2.2 Measurements of TFT characteristics 16 Ⅲ. Results and Discussion 18 3.1 PUF based on capacitance 18 3.1.1 Distribution of the capacitance 18 3.1.2 Converting the capacitance values to binary codes 19 3.1.3 PUF Evaluation of the capacitors 21 3.2 IGZO TFTs based on PUF 24 3.2.1 Distribution of threshold voltage 24 3.2.2 PUF Evaluation of the IGZO TFTs 26 Ⅳ. Conclusion 30 4.1 Summary 30 4.2 Next Step 30