Study On Phenomenon Of Series MIM Structure In Nanoscale Based On Ultra-Fast PCSS

With many advantages, such as simple construction, fast response, high sensitivity, stable triggering and realizing the separation of light and electricity, Photoconductive Semiconductor Switch (PCSS) are widely used in many fields, such as producing pulse of high power and ultra-broad band and ultra-fast electronics. This dissertation discussed how titanium oxidation line were fabricated with Atomic Force Microscope (AFM) via anodic oxidation to form new type of Ultra-fast PCSS, and also the phenomenon of such Metal-Insulator-Metal (MIM) tunneling junction was studied. The main content of our research work is listed as follow:1. Research on the theory of photoconductive switch, including fundamental theory, work modes and the calculation and research on theoretical model. The substrate materials of photoconductive switch were compared and selected, the configuration of PCSS was designed, and the implement methods of Ultra-fast PCSS were analysed.2. The fabrication process of PCSS was designed and put into practice. Photo-lithography, Dual Facing Target Sputtering System and AFM anodic oxidation were combined to fabricate the Ultra-fast PCSS on GaAs. Among which, the study of AFM anodic oxidation was emphasized. Besides, dark I-V curve of PCSS had been tested and compared before-and-after AFM anodic oxidation, which proved that nano-titanium oxidation line had improved dielectric strength of Ultra-fast PCSS.3. The optimum conditions of AFM anodic oxidation were biased voltage of 8V, scanning speed of 0.1μm/s and relative humidity of 30%~50%. Under such condition, the research and fabrication experiment of nano-titanium oxidation lines by AFM anodic oxidation was carried out. Fabrication mechanism and theory model of AFM anodic oxidation were analysed also. In addition, the thickness, surface flatness and conductivity of ultra-thin titanium film were tested and proved all according with our requirement. The linearity and consistency of height and width of oxidation titanium lines were measured and calculated by fabricate six oxidation titanium lines under the optimum condition.4. Series MIM tunneling junctions were fabricated, and study on tunneling junctions and running through barrier were studied. The description methods and I-V characteristic of tunneling junctions were conducted and investigated also; meanwhile, a method model of calculation was developed.