Research Of Thz Detectors Array Chips Applicable For Flip Chip Packaging Technology

Terahertz（THz）detector is an important component in THz science and technology.It has been widely concerned and studied because THz detector has a tremendous practical value in aspects of security check,imaging,material components identification and so on.In THz frequency range,the detector,which consists of a planar antenna and a sensing unit,is usually designed to improve the coupling efficiency.Therefore,the antenna performances decide the working frequency and detection property of the detector.This thesis centered around the THz planar double-slot antenna and detectors array chips.And the results establish the technical foundation for the connection between antenna-based THz detectors array chips and readout integrated circuits in flip chip packaging,main research results are as follows:1.We designed a kind of planar double-slot antennas for THz detectors array.And the corresponding frequency performances of double-slot antennas in different periods were studied.By using micro-fabrication technology,we integrated the Nb₅N₆ thin film microbridge with the double-slot antennas in different periods,and fabricated THz detectors array chips.Then we characterized the THz response properties of detectors array chips.The measured results keep consistent with simulated results,verifying that the period can directly affects the response frequency and sensitivity of detectors array.And it reveals that the maximum radio-frequency（RF）voltage responsivity（Rv）of Nb₅N₆ THz array detectors with 300 μm period is 186V/W at 0.65 THz.The measured voltage noise intensity at 4kHz was 11nV/√Hz.Its minimum noise equivalent power（NEP）at 0.65 THz was about 60pW/√Hz.2.On the basis of above-mentioned researches,during the process of the connection between antenna-based THz detectors array chips and readout integrated circuits in flip chip packaging,we first proposed the design concept that eliminated the effect of multilayer metal sheets by a large metal surface,to solve the problem about unpredictable influence of multilayer metal sheets on antenna performances.For the readout integrated circuits with the period of 250 μm,we designed a kind of rectangular double-slot antennas which were suitable for the application in flip chip technology.For comparison,the traditional dipole antennas were also designed and analyzed.Using CST Microwave Studio,we investigated the effect of the boards added with different metal patterns on properties of these two kinds of antennas array in flip chip packaging.Results showed that the rectangular double-slot antennas array could effectively reduce the effect of the board on its performances,revealing a good coupling efficiency with respect to THz signals.3.Similarly,by using micro-fabrication technology,we integrated the rectangular double-slot antennas into the Nb₅N₆ THz detectors array chip（period: 250 μm）.In a tunable Fabry-Pérot（F-P）cavity,we studied the properties of detectors array under the circumstances of different distances between the metal reflector and chip substrate.The measured results revealed that the change rate of peak voltage responsivity of Nb₅N₆ THz detectors array was only 23% when altered the distance between the metal reflector and chip substrate.And the resonant frequency remained at 0.6442 THz around.However,the change rate of peak voltage responsivity of traditional Nb₅N₆ THz detectors array integrated with dipole antennas reached up to 45%,the corresponding resonant frequency was obviously changed.Experimental results showed that Nb₅N₆ THz detectors array applied rectangular double-slot antennas could effectively reduce the interference effect of the metal reflector in readout integrated circuits,indicating that it had great application prospects in flip chip packaging.