Fabrication Of Photosensitive Organic Field Effect Transistors And Study On Electrode Modification

With development of semiconductor technology,organic field effect transistors(OFETs)have become an important part of organic electronic products.It can be widely used in the fields of circuit switches,flexible displays,storage,and its production cost is lower than inorganic semiconductor devices,which has great potential.Therefore,the performance requirements for organic field effect transistors are also increasing.In order to meet the industry's demand for high performance organic field effect transistors,research on high quality OFET is a necessary and long-term task.In this paper,the working principle of organic field effect transistor and the characterization method of electrical characteristics are studied.It is determined that the performance of the device is improved by modifying the metal and semiconductor contact interface of the field effect transistor.Various modification schemes are designed to prepare the device and measure it.The electrical properties verify the modification effect.The main content can be divided in two parts:First,we produced a near-infrared organic field-effect transistor with channel transmission layer of pent and functional layer of SnPc.The results indicate that the device shows poor performance.By introducing C60 thin film with hole injection function as device's motor modification layer.The photosensitivity of the device has been greatly improved.The max light responsivity has reached 19.19A/W.The thickness of C60 was optimized,and OFET with C60 thickness of 20nm and 30nm were prepared.The results show that the dark current of the device is effectively suppressed when the thickness of C60 is 20nm,and the light responsivity of the device is also optimal.In the second part,we mainly study the effect of asymmetric electrodes on organic photosensitive field effect transistors.OFET with five different structures were prepared with symmetric gold electrodes,symmetric silver electrodes,asymmetric metal electrodes,MoO3 modified asymmetric metal electrodes,BCP and MoO3 modified asymmetric electrodes.The first two exhibited poor photosensitivity;the last structured device exhibited the best photosensitivity,with a maximum light responsivity of 2.8 A/W,which was 3.6 times the light responsivity of symmetrical gold electrode devices.