The Fabrication And Characteristics Of Vertical Organic Photoelectric Transistor

Organic semiconductors have been extensively used in photoelectronics because of its advantages of lightweight, low-cost and compatibility with flexible substrate. In this paper, using vacuum evaporation and sputtering process, we prepared a photoelectric transistor with the vertical structure of Cu / Cu Pc / Al / Cu Pc / ITO. The material of Cu Pc semiconductor has good photosensitive properties. Excitons will be generated after the optical signal irradiation in semiconductor material, then transform into photocurrent under the built-in electic field by the Schottky contact, as the organic transistor drive current, makes the output current multiplication.The results show that the I-V characteristics of transistor is unsaturated. The increase of the base voltage inhibit the current between the collector and emitter. When device was irradiated by full band(white), 625 nm, 700 nm light, its working current significantly increased. In white light, when Vec=3V, the ratio of light and no light current was ranged for 2.9-6.4 times.In dark, β=16.5. In 700 nm, 625 nm and white light, the photocurrent of the device was 0.0344μA, 0.0714μA, 0.15μA respectively, and the sensitivity of the device was 0.1632 A/W,0.2023 A/W,0.0206 A/W respectively. The collector current and photocurrent of the device in white light was much larger than its in monochromatic light, but the sensitivity of the device in white light was lower because of the incident power of white light was much larger than its in monochromatic light.