Research On Characteristics Of Double Injection High Photomultiplier Organic Detector

Organic photodetectors(OPDs)have many advantages,such as low cost,large absorption coefficient,can be prepared in a large area,and a wide range of active layer materials,etc.,so they show good application prospects in the field of photoelectric detection,of which th e multiplier type Organic photodetectors have received extensive attention due to their excellent detection capabilities.At present,the multiplier organic photodetector still has the problems of high working voltage,complicated preparation process and high material cost.To solve the above problems,this paper proposes a double-injection multiplying OPDs based on bulk heterojunction(BHJ).By adding a hole blocking layer and doping traps into the active layer,the device achieves good photoelectric performance.In the research process,three sets of multiplying organic photodetector devices were prepared.First,a barrier multiplying device was prepared.Its structure was:ITO/C60/P3HT:PC61BM/Al.The experiment shows that the addition of the C60 barrier layer has little effect on the optical absorption of the active layer film of the device.When the thickness of the C60 is 15 nm,the device achieves the best performance,with a bias voltage of-1V and a wavelength of 460 nm and an optical power of 0.21 mW·cm-2 External quantum efficiency(EQE)reached 278%under the light,and the specific detection rate was 8.52 × 1012 Jones.Then,a trap-doped multiplying device was prepared.Its structure was:ITO/PEDOT:PSS/P3HT:PC61BM:C70/Al.Experiments showed that after doping the active layer with electron trap C70,the fluorescence spectrum of the film burst off,the light responsivity of the device improves.When the doping concentration is 0.3 mg,the device achieves the best performance.The EQE under-1V bias and illumination reaches 316%,and the specific detection rate is 4.07 × 1012 Jones.Finally,by doping th e C70 electron trap on the basis of the first group of optimal devices,a double-injection multiplier device was prepared.The device structure was ITO/C60/P3HT:PC61BM:C70/Al.The experiment showed that:At 0.3 mg,the device achieves the best performance.The EQE under-1V bias and light reaches 455%,and the specific detection rate is 1.49 ×1013 Jones.In summary,the research results show that:the double injection multiplier device can further improve the light responsivity of the device;adding a hole blocking layer can reduce the dark current of the device,thereby improving the specific detection rate of the device;the double injection device has a larger The linear dynamic range has good detection ability for strong light and weak light;doping traps cause the response speed of the device to be affected to some extent,but still meet the imaging requirements of the image sensor.In summary,this article provides a design method for multiplying OPDs with high detection rate,simple process,and low operating voltage.In summary,the research results show that:the double injection multiplier device can further improve the light responsivity of the device;adding a hole blocking layer can reduce the dark current of the device,thereby improving the specific detection rate of the device;the double injection device has a larger The linear dynamic range has good detection ability for strong light and weak light;doping traps cause the response speed of the device to be affected to some extent,but still meet the imaging requirements of the image sensor.In summary,this article provides a design method for multiplying OPDs with high detection rate,simple process,and low operating voltage.