Research On The Contact Of Graphene And GaN Materials

Due to its special structure, Graphene has very good optical, electrical, mechanical and other properties and it is regarded as a breakthrough of the new materials. Thanks to the wide band gap, thermal stability, high working power and other properties, Ga N materials have become the "most important, after the silicon semiconductor material." It will bring great benefits for the photoelectric and microelectric devices if we can successfully combine the graphene with Ga N materials.At present, it has been reported that graphene electrodes are used to improve the luminous efficiency of Ga N-based LED. However, there are still some problems should be solved, such as the transfer process. The graphene was usually transferred from the Cu substrate by etching process, which is very hard to control the transferring process and limite the use of graphene into the Ga N material. Furthermore, the physician mechanism of the contact of graphene and graphene is unclear.In this paper, we studied the contact of the graphene and Ga N material, mainly focus on the physical mechanism and the contact behavior between graphene and Ga N.. The main contents of this paper are as follows:1) The research of the contact behavior between graphene and Ga N materials, focusing on how to form good contact between graphene and Ga N material by simple and repeatable method.2) The investigation of l mechanism of the contact property when graphene and Ga N has being contact, focusing on the forming conditions and the physical mechanism of the good ohmic or Schottky contact.3) Research on optical, electrical and mechanical properties of graphene and Ga N contact and graphene/Ga N dual detectors were fabricated.The originals in this paper are as follows:1) Using the liquid graphene instead of conventional graphene grown by CVD on Cu substrate to form the contact of graphene and Ga N. Good contact between graphene and Ga N were realized through control the quantity method or spinning method using the liquid graphene. Compared with the traditional method of graphene transferred by etching process, the method used here is simple and repeatable.2) Graphene/Ga N detectors were fabricated, which have spectral response both at ultraviolet and near infrared region. The effect of the folds and the different pairs of graphene edge shapes on the contact property were also studied. It shown that the edge shapes and folds adjusted the electrical properties performed after graphene exposured to Ga N materials. These folds can be regarded as conductive paths among the sheet-like graphene structures, with the function to improve the shortcomings of poor electronics conducting. Furthermore, the shapes of graphene folds can help to broaden the width of the space charge region and increase the Schottky barrier height in the destination to improve the light response.