Analysis of a Flexible Photoconductor, Manufactured with Organic Semiconductor Films

• Published in: Micromachines (Basel) Vol. 15; no. 4; p. 446
• Main Authors: Cantera Cantera, Luis Alberto, Sánchez Vergara, María Elena, Hamui, Leon, Mejía Prado, Isidro, Flores Huerta, Alejandro, Martínez Plata, Teresa Lizet
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01-04-2024
• Subjects: Activation energy; Annealing; Approximation; Carrier density; Current density; Electrical properties; Electron mobility; Electrons; flexible device; Heterojunctions; High vacuum; Indium tin oxides; Knoop hardness; Mechanical properties; Microscopy; Optimization; organic photoconductor; organic semiconductor; planar heterojunction; Polyethylene terephthalate; Semiconductors; Silicon; Temperature; Tensile strength; Thin films; Vacuum evaporation; flexible device; electrical properties; organic semiconductor; planar heterojunction; organic photoconductor
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi15040446

This work presents the evaluation of the electrical behavior of a flexible photoconductor with a planar heterojunction architecture made up of organic semiconductor films deposited by high vacuum evaporation. The heterojunction was characterized in its morphology and mechanical properties by scanning electron microscopy and atomic force microscopy. The electrical characterization was carried out through the approximations of ohmic and SCLC (Space-Charge Limited Current) behaviors using experimental J-V (current density-voltage) curves at different voltages and under different light conditions. The optimization of the photoconductor was carried out through annealing and accelerated lighting processes. With these treatments, the Knoop Hardness of the flexible photoconductor has reached a value of 8 with a tensile strength of 5.7 MPa. The ohmic and SCLC approximations demonstrate that the unannealed device has an ohmic behavior, whereas the annealed device has an SCLC behavior, and after the optimization process, an ohmic behavior and a maximum current density of 0.34 mA/mm
were obtained under blue light. The approximations of the device's electron mobility (μn) and free carrier density (n0) were performed under different light conditions, and the electrical activation energy and electrical gap were obtained for the flexible organic device, resulting in appropriate properties for these applications.