Page 10 - Organic Electronics in Sensors and Biotechnology

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4.1.2 The IS of an Organic MIS Structure . . 120
4.1.3 Charge-Time Behavior of Capacitive
Multilayers . . . . . . . . . . . . . . . . . . . . . . 123
4.2 Integrated Pyroelectric Sensors . . . . . . . . . . . . 128
4.2.1 Introduction . . . . . . . . . . . . . . . . . . . . . 128
4.2.2 Theoretical Background—
Pyroelectricity . . . . . . . . . . . . . . . . . . . . 129
4.2.3 Pyroelectric Polymer Materials . . . . . 131
4.2.4 Description of the Sensor Part . . . . . . 135
4.2.5 Description of Transistor Part . . . . . . 153
Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
5 Progress and Challenges in Organic
Light-Emitting Diode-Based Chemical
and Biological Sensors . . . . . . . . . . . . . . . . . . . . . . . . 165
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
5.2 Structurally Integrated OLED/Sensing
Component Modules . . . . . . . . . . . . . . . . . . . . 168
5.3 Sensors Based on Oxygen Monitoring . . . . . . 169
5.3.1 Advances in Monitoring Gas-Phase
and Dissolved Oxygen . . . . . . . . . . . . 170
5.3.2 Multianalyte Sensing . . . . . . . . . . . . . 177
5.3.3 Sensors for Foodborne Pathogens . . . 181
5.4 OLED Sensing Platform Benefits and Issues . . . 182

5.5 OLED/Sensing Component/Photodetector
Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
5.6 Concluding Remarks . . . . . . . . . . . . . . . . . . . . 187
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
6 An Introduction to Organic Photodetectors . . . . . . 193
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
6.2 Conventional Photodetectors . . . . . . . . . . . . . 195
6.3 OPV Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
6.3.1 Device Architectures . . . . . . . . . . . . . . 202
6.3.2 Device Fabrication . . . . . . . . . . . . . . . . 204
6.3.3 Current-Voltage Characteristics . . . . . 208
6.3.4 The Equivalent Circuit . . . . . . . . . . . . 215
6.4 Device Characteristics . . . . . . . . . . . . . . . . . . . . 217
6.4.1 Spectral Response . . . . . . . . . . . . . . . . 217
6.4.2 Rise Time and Cutoff Frequency . . . . 218
6.4.3 Intrinsic Photodiode Noise
Characteristics . . . . . . . . . . . . . . . . . . . 221
6.5 Measuring a Current . . . . . . . . . . . . . . . . . . . . . 225

6.5.1 The Transimpedance Amplifier . . . . . 226
6.5.2 The Charge Integrator . . . . . . . . . . . . . 232