Addressable Carbon-nanotube-film-based Field Emission Displays

As one of the quasi one dimensional tubular structure material, CNTs has a large C-C bond energy,a high length-diameter ratio and a high specific surface area, etc, which give it some excellent mechanical strengths, good electrical and thermal conductivities, stable chemical properties, outstanding field emission characteristics and so on. All these superiorities have made the CNTs to be a very wide range of applications, such as in the field of hydrogen storage, supercapacitor, composite materials, lithium battery and biomedical engineering, etc.First of all, in the fundamental section of experiments, we mainly introduced some aspects as follows:the preparation of various slurries used for cathode and anode, the detailed process of mechanical erosion and printing, the preparation of CNT-film on the cathode and phosphor powder film on the anode by using the screen printing, along with their fritting and processing process. At the end of this part, we present the simple assembly and testing process of Field Emission Device. The preparation of the anode and cathode like this, however, can not fulfill the requirements of packaging in subsequent experiments. So in this paper, I have made a optimization procedure for the field emission cathode. Through various improvement and processing, the working voltage is successfully reduced to 200-250V and at the same time the current density is enhanced, which also leads to the improvements of its field emission uniformity and brightness.In the next place, the graphene, which has a excellent performance, has been made by the using the method of chemical oxidation reduction and applied to the three kinds of CNTs composites; subsequently the influence on their field emission characteristics has been investigated after adding the graphene. As the result shows, the addition of graphene can enhance the field emission effect of CNTs thin film. In these three kinds of carbon nanotubes, the effect of DWCNTs is the best, which turn-on field and threshold electric field is low to 0.6V/μm and 1.2V/μm, respectively, and its current density is also high on 16mA/cm2. The second one is the type Ⅰ MWCNTs, which is short and thin, and its current density is about 4-8mA/cm2. The worst effect belongs to the type Ⅱ MWCNTs, because its current density is generally under 2mA/cm2.Ultimately, the vacuum packaging has been successfully carried out for the optimized cathode and anode. The detailed fabrication process includes the dispensing process on the glass substrate, which is by use of the dispensing machine filled with low melting point glass powder; the sealing process between anode and cathode and the vacuum packaging process of FED devices. Simultaneously, the working principle of the drive circuit related to FED is simply presented. Finally we have connected the rive circuit with the packaged FED module, and successfully turned on the large FED screen, which is pieced together by these modules.