Plasmon-Enhanced Silicon Near-Infrared Photodetectors: Translating Fundamental Interface Design/Engineering to Enhance the Photoresponse

For the past few years, all silicon photonics technology gradually becomes one of the popular research topics in the world. Currently, it is still lack of high quality silicon based NIR (Near infrared) light detector for optical transmission. Due to the high bandgap of silicon, it cannot absorb the NIR wavelength which is used by optical communications. The physical effects of NIR absorption in silicon which is using various process technologies have been proposed in succession. Because the structure of metal-silicon Schottky junction diode can be simply produced and easily integrated in crystalline silicon Integrated Circuit, it has huge potential of applications. In recent years, the researches of Schottky device are to put emphasis on discussing the surface plasmon resonance behavior. It has influences on light absorption rate in metal and light responsivity in device. However, the concentration of defect in metal-semiconductor interface has huge influences on the light responsivity and sensitivity of the device in this structure of crystalline silicon plasmon optical detector. As we know, there is no research about the influence between the interface property and Schottky optical detector so far. Therefore, in the first year of this program, we will grow and module the materials of the interface layer and its physical properties (such as electron affinity, thickness and passivation effects, etc.) to discuss the influence between interface and internal photoemission carrier transmission. Moreover, it is concerned that if reduce the reverse saturation current, the light responsivity of the device can be improved or not. In the second year, we adjust the physical property of the crystalline silicon substrate (such as doping concentration and fabricating the nanostructure on silicon surface) and then combine with the growth of the interface materials. It is expect that obtain an optimized process parameter to lower the reverse saturation current. Besides, it has to keep the hot electron being able to tunneling or across the interface in order to promote the light responsivity and sensitivity of the device.