Study On Photodetector Based On The Monolithic Integration Of The The Vertical Cavity Semiconductor Optical Amplifier And PIN

As an essential component in the optical communication system,the photodetectors have been intensively investigated.However,the conventional APD photodetectors are unable to meet the requirements of high-speed communication systems(such as 40/ 100 GPON,100G data transmission system and so on)due to their limited gain bandwidth product with the substantial growth of high-bandwidth business such as super HDTV,video communication and so on.PINs integrated with optical preamplifiers have attracted much attention owning to their superior performance among many solutions.In the existing works,erbium-doped fiber amplifiers(EDFAs)and semiconductor optical amplifiers(SOAs)have been widely employed as optical preamplifiers for integration.However,EDFAs are not suitable for access networks and short haul communication systems because of their large size and expensive cost,and SOAs have the disadvantages of low coupling efficiency to optical fiber,polarization sensitivity and poor noise performance,which can not fully meet the actual demand.In this thesis,we propose a novel photodetector based on the monolithic integration of the VCSOA and PIN.Under this strategy,VCSOAs meet all the criteria that are impossible for in-plane SOAs,and also show the potential of being integrated into 2-D array architectures,the vertical structure also allows for on wafer testing,which significantly recuces manufacturing and testing cost,making it promising in many applications.In this thesis,the basic theory of VCSOA-PIN is introduced,the structure design and simulation results is presented.Then the device samples are fabricated.Finally,some modifications are made on our initial design.The main research works are as follows:(1)Introduction of basic structure,design principle on the proposed device,the establishment of 1-D traveling wave model and carrier transport model for simulation.(2)Establishment of measurement system on VCSOA-PIN photodetector,including the design of laser transmitting circuit and receiving circuit,test system on static characteristic and dynamic characteristic.Finally finished the experimential test.(3)Modifications on initial design on the consideration of reducing series resistance for improving device gain and high-speed performance.