Design And Research Of Silicon-based Light Source For Sensing

With the rapid development of integrated circuits,all-silicon photonics is attracting more and more attention from researchers.All-silicon photonics is an interconnection technology that uses silicon-based materials as photonic devices,and all-silicon photonic biosensors are one of the new directions that have been receiving significant attention.All-silicon photonic biosensors are a sensor technology that combines optoelectronics and biology principles to detect and analyze biological systems such as biomolecules,cells,and microorganisms.Their importance is mainly reflected in the following aspects:high sensitivity,real-time detection,miniaturization,and wide applications.Therefore,the development of all-silicon photonic biosensor technology will have a significant impact on fields such as biology,medicine,and life sciences,and is of great significance for promoting biological research and improving human health.However,one of the main components of all-silicon photonic biosensors,the silicon-based light source,still faces many limitations in its applications.Although various silicon-based light-emitting devices have been developed,the disadvantages of silicon materials,such as low luminous efficiency and high fabrication complexity,remain a challenging obstacle to overcome.Based on in-depth research on silicon-based avalanche light-emitting devices,this thesis proposes a N~+PN~+structure polycrystalline silicon avalanche light-emitting device.The device is manufactured using standard CMOS technology,which provides a foundation for integrated applications.By studying the structural parameters,it is found that the width of the base region can effectively modulate the breakdown condition of the device.Devices with narrower base regions have better light-emitting performance,lower light-emitting threshold voltages,and stable operating voltages that can be reduced to around 7 V.Moreover,by establishing a small signal model,the frequency response characteristics of the device were analyzed,and the measured data showed that the highest switching speed of the device can reach the GHz level.In addition,this thesis also conducted an in-depth analysis of the electroluminescence characteristics of the device,and the emission spectrum range of the device is within 400-1000 nm,which overcomes the limitation of the emission wavelength of silicon materials.It was also found that within a certain range,the light emission intensity of the device has a linear relationship with the supply voltage and current,which is important for its photoelectric modulation.Finally,by comparing the light intensity test data of the N~+P-type device,it was found that the bipolar-type device has lower power consumption.Under the same electrical power consumption,devices with narrower base regions have higher light emission intensity.Bipolar-like polycrystalline silicon avalanche light-emitting devices have many advantages,such as low light emission threshold voltage,high switching speed,linear modulation characteristics,and low power consumption.This makes it suitable for use in all-silicon optoelectronic biosensors.By exploring its coupling scheme with optical waveguides,its feasibility as a light source integrated on a sensing chip is demonstrated.