JOURNAL OF ELECTRONIC MATERIALS, 2026 (SCI-Expanded, Scopus)
A flexible projected capacitive touch panel (PCTP) based on lithographically patterned indium tin oxide (ITO) electrodes on polymer substrates is presented. The device employs a G1F-type architecture, in which a single ITO-patterned sensing film is laminated to a cover substrate, using polyethylene terephthalate (PET) as the sensor substrate and polycarbonate (PC) as the flexible cover lens. A 6 & times; 3 sensing matrix with an active area of 3 & times; 4 cm2 was fabricated and electrically characterized using a TTP223-based detection circuit with tunable sensitivity controlled by an external capacitor (Cs). Systematic sensitivity analysis demonstrated three distinct operating regimes: (i) Cs = 0 pF produced maximum sensitivity with detectable proximity response but exhibited noticeable signal fluctuation due to environmental noise; (ii) Cs = 5 pF provided stable and spatially uniform touch detection across all sensing nodes with minimal false triggering; and (iii) Cs = 10 pF reduced parasitic noise effects but decreased touch responsiveness. The optimized configuration (Cs = 5 pF) achieved reliable touch detection with balanced sensitivity and noise immunity. Mechanical reliability testing showed that electrode resistance increased gradually during cyclic bending up to 300 cycles, without abrupt electrical failure or loss of conductivity, confirming preserved electrode continuity and strong ITO-polymer adhesion. These results quantitatively confirm that polymer-based PCTPs can maintain stable electrical performance under mechanical deformation while offering tunable sensitivity control through simple circuit parameter adjustment. The study establishes practical design guidelines for lightweight, foldable, and wearable electronic applications.