| Due to its low cost,high refractive index contrast,and compatibility with mature complementary metal oxide semiconductor processes,silicon-based photonic integrated chip has become one of the popular choices to realize optical interconnection technology.However,due to the limitation of the silicon material itself,it is difficult to realize many key functional devices in the photonic integrated circuit only relying on silicon.By introducing other materials with excellent optoelectronic properties such as metals,germanium and two-dimensional materials,it has become the main method to solve this problem in the silicon-on-insulator platform.Transition metal carbides or nitrides（MXene）,a new advanced two-dimensional（2D）material,has many excellent optoelectronic properties,such as strong saturable absorption,high conductivity,non-flat broad-spectrum light absorption,high photothermal conversion efficiency,and work function tunability,making it very suitable for optical applications field.And because of its water-soluble characteristics,MXene can be transferred on a large scale by simple processes such as spraying and spin coating.Therefore,introducing MXene into silicon-based optical platforms to achieve high-performance photonic devices has broad prospects.However,most of the published studies on MXene are copmputational,and very little has been done experimentally.In addition,it is very difficult to accurately transfer MXene to micro-nano photonic devices.In this paper,the most representative Ti3C2TXmaterial in MXene is selected for the research of key photonic devices in silicon-based optical platforms.Using a set of perfect process method for accurate transfer of MXene materials,an integrated multi-wavelength sensor,a light-assisted tuning microring modulator and a waveguide intergrated Schottky photodetector are finally realized.The main research content of this thesis can be summarized as follows:（1）The two basic photonic device structures of MZI and microring,thermal phase shift principle and the ideal Schottky junction model are studied,which all provide theoretical support for following device design.Then the device manufacturing and testing methods are introduced in detail,and finally a set of process methods for accurately transferring MXene to silicon-based photonic devices are proposed.（2）We propose and demonstrate to directly utilize Mxene for the application of all-optical swithces.By utilizing the non-flat broad-spectrum light response of MXene and the on-chip Mach-Zehnder interferometer（MZI）structure,an on-chip multi-wavelength sensor is designed and fabricated.Experimental results show that the tuning efficiency of the device at 980 nm and 1540 nm is 0.19π?m W-1?mm-1 and 0.12π?m W-1?mm-1 respectively,and the response time is 23.4μs.Compared with other reported two-dimensional materials,the device is an order of magnitude more efficient and two orders of magnitude shorter in response time.（3）We propose and demonstrate to directly utilize Mxene for the application of on-chip optical tuning.By utilizing the high photothermal conversion efficiency of MXene,a light-assisted tuning silicon-based microring modulator with large optical bandwidth is designed and fabricated.Different from the traditional electric adjustment and thermal adjustment,this device realizes the large-range tuning of the micro-ring resonance peak by controlling the pumping power.Finally,we demonstrate that under high-speed modulated signals injection,optical tuning is used to compensate for the introduced wavelength shift,thereby ensuring optimal transmission of the signal.（4）We propose and demonstrate to directly utilize Mxene for the application of silicon waveguide integrated photodetection.By transferring MXene to a p-type doped silicon waveguide to form a Schottky junction and utilizing the work function adjustability of MXene,a silicon waveguide integrated Schottky with adjustable barrier is designed and fabricated.In the experiment,we use thermal annealing to change the work function of MXene and then adjust the Schottky barrier.The measured results show that the work function of MXene is reduced by 0.23 e V,and the Schottky barrier is increased by 0.08 e V.Finally,the responsivity test confirms the adjustability of barrier with the responsivity of device reduced by an order of magnitude. |
