InP Microlens Arrays For PIN Detector

The concealment and effectiveness of infrared detection make it mainly used in the military field,but also rapidly open up new applications and markets.PIN detector converging microlens array to a certain extent,greatly enhance the detector detection rate and responsiveness,thereby enhancing the performance of the detector,expanding the scope of the application of the detector.The microlens array itself is a micro-optical device with both concentrating and imaging functions.It is small,lightweight and easy to integrate.The combination of the microlens array and the infrared focal plane of the PIN detector is simple and effective,and has become a research hotspot to improve the performance of the detector.The main work of this thesis is as follows:(1)The principle of the PIN detector converging microlens array was analyzed in detail,and the effective light entering area and the light energy utilization ratio of the micro lens array and the infrared focal plane of the PIN detector were compared,the change of detector response and detection rate after integration was theoretically analyzed.(2)The advantages of the rectangular aperture microlens array with respect to the circular aperture microlens array in improving filling factor were compared,the rectangular aperture spherical microlens array with high filling factor was designed for the InP infrared focal plane array at 1064 nm wavelength.(3)Lithography hot melt method was adopted.A process of making a rectangular aperture spherical microlens array was designed and developed.The process parameters of each link were optimized by theoretical analysis and a large number of process experiments.(4)In order to obtain the microlens array with high crown height and high fill factor on the 2-inch substrate,the thick lithography process and the ICP deep etching process were carefully explored,and the methods of secondary spinning,shortening the development time,cycle etching were proposed.(5)The shape and optical properties of the microlens array were tested,and the filling factor,the height uniformity information and the uniformity information of the focal spot diameter were obtained.Finally,it was found that after integration of the microlens array,the intensity of the photocurrent of PIN detector significantly improved.This shows thatthe micro-lens array produced in this paper has a strong practicality,and its energy-generating function has a significant effect on the performance enhancement of the infrared focal plane array.