Research On Preparation Method And Photoelectric Properties Of Multilayer Graphene Film

Graphene,a two-dimensional semiconductor material,has great application potential in photodetectors due to its excellent photoelectric properties.However,single-layer graphene has the problems of low light absorption and short carrier lifetime,which limits its photoelectric performance.The use of single-layer graphene and light-absorbing materials to form a heterojunction can solve the problems of low absorbance and short carrier lifetime,and can increase the optical gain of the photodetector.However,the response band of this type of heterojunction device is often limited by the inherent band gap of the light-absorbing material,and cannot take advantage of the wide-band light absorption characteristics of graphene.In response to the above problems,this paper proposes a way to broaden the detection band of graphene-silicon heterojunction devices by using the composite of multi-layer graphene and silicon.The preparation method of multi-layer graphene was systematically studied,and the rapid preparation of multi-layer graphene was realized by means of dual polymerization assisted transfer.Research the key technology of graphene photodetector preparation,develop double-layer glue metal electrode peeling and graphene patterning technology,realize the good preparation of the device.At the same time,the electrical properties of graphene field effect transistors and the photo-response characteristics of graphene-silicon heterojunction photodetectors in different wavelength bands were experimentally verified.The main research contents are as follows:1.Double-polymer assisted preparation of multilayer graphene analyzed the difficulties of using single polymers(PMMA,PDMS)to assist the transfer of two-dimensional materials in the preparation of multilayer graphene.It is proposed to use PMMA and PDMS to assist the transfer of multi-layer graphene.The effects of different temperatures and different drying times on the binding force of the PDMS/PMMA interface and the graphene/silica interface were studied,and the mechanism was analyzed.This method is used to realize the preparation of 2-8 layers of laminated graphene,and the material is characterized.Finally,the method is extended to realize the lossless transfer of Mo S₂.2.Research on the key manufacturing process and electrical properties of graphene field-effect transistors Aiming at the problem of the low success rate of electrode stripping during device preparation,the influence of the cross-sectional morphology of the photoresist after exposure and development on the stripping success rate is analyzed.The double-layer glue(LOR/S1805)was used to replace the single-layer photoresist(S1805)for exposure,and the change rule of the cross-sectional morphology of the double-layer glue after different development time was studied.Choosing appropriate process parameters finally achieved a high success rate of metal electrode stripping.Further analysis and study of the interaction between different photoresist and oxygen plasma,the use of double-layer glue to achieve large-area patterning technology of graphene film.The graphene field effect tube was successfully prepared,and the electrical characteristics of the single/multilayer graphene field effect tube and the doping of the device with different process methods were experimentally tested and analyzed.3.The photoelectric performance research system of multi-layer graphene-silicon heterojunction photodetector analyzes the photoelectric conversion mechanism of single-layer graphene-silicon heterojunction,selects appropriate doped graphene and silicon materials for compounding,and successfully prepares single-layer graphene-silicon heterojunction.Layer and multilayer graphene-silicon heterojunction photodetectors.The photoelectric response of the device under different wavelength bands was tested,and the photoelectric conversion mechanism of the multilayer graphene-silicon heterojunction was analyzed in combination with experiments.Finally,the experimental verification of the wide-band response was realized.