poster-icon

MA04.11.02 : Transparent Capacitive Pressure Sensors with Ultralow Electromagnetic Interference

5:00 PM–7:00 PM Apr 5, 2018

PCC North, 300 Level, Exhibit Hall C-E

Description
Taehoon Kim1 Gwangmook Kim1 Hyeohn Kim1 Wooyoung Shim1 Sungsoon Kim1

1, Yonsei University, Seoul, , Korea (the Republic of)

The disturbance by Electromagnetic interference (EMI) may degrade the performance of the circuit or even stop it from functioning. EMI shielding is a way to reduce the effects of EMI on a desired space. In general, materials with high electrical conductivity are effective for EMI shielding. But for this reason, circuits or devices that use high-conductivity materials also serve to block electromagnetic signals unintendedly. For example, when a metal or conductive polymer electrode is coated on a commercial touchscreen, the electric field is disturbed and can not be recognized as a 'touch' when the finger approaches. PEDOT: PSS, one of the conductive polymer, also has EMI Shielding Efficiency (EMI SE) due to its high electrical conductivity. Absorption loss is negligible when PEDOT: PSS is thinly coated on a scale of several hundred nanometers, but thickness-independent reflection loss still interferes with the electromagnetic wave signal. We fabricated thin-film electrodes of tens of nanometers to make different electrical tendencies and structures than bulk by diluting in solution. At that thickness range, the conductive pathways are changed and thus the electrical conductivity can be controlled. Therefore, we modifyed the structure of PEDOT: PSS to fabricate electrodes with very low reflection loss. We also fabricated a capacitance pressure sensor using this optimized electrode and attached it to a touch screen to produce a transparent film capable of 3D force input.

Tags