Investigations Of Key Technologies Of Terahertz Amplifier Based On InP Process

Terahertz wave is in the transitional stage between electronics and microphotonics,and has properties of microwave and optical wave radiation,which exhibits an extensive application prospect in terahertz communication,terahertz radar,terahertz detection and so on.Besides,terahertz amplifier is an important part of terahertz front-end,which is used to amplify the transmitted and received signals.In this thesis,the small signal modeling of domestic InP DHBT(double heterojunction bipolar junction transistor)and the monolithic design of terahertz amplifier are studied,and the terahertz monolithic packaging technology is also studied.The major work can be summarized as follows:(1)Research on InP DHBT small signal model.In view of the lack of domestic InP DHBT terahertz model,the small signal model is developed based on the measured results of 0.25 μm InP DHBT.Finally,these model results agree quite well with the measured S parameters from 0.1 to 40 GHz,and it lays a foundation for the monolithic design of the amplifier.(2)The design of terahertz monolithic amplifier.Considering of the lack of high-performance terahertz monolithic amplifier in China,a power combined amplifier and a small signal gain amplifier are designed,which operating at 220-GHz-band and 320-GHz-band,respectively.Meanwhile,"unit whole method" is adopted to overcome the mismatch of bias circuit and RF path in terahertz band simulation.(3)Research on terahertz packaging technology.1)An inverted microstrip transmission line packaging structure is introduced for solving the significan parasitic effect and high loss of gold wire bonding at terahertz frequencies.This none-gold-bonding structure make it easier to assemble compared with the inverted CPW packaging structure.The measured results show it exhibits a 0.9-1.8 dB single-ended insertion loss from 110 to 170 GHz.2)Besides,different transition structures and gold wire bonding modes are studied in this thesis to solve the problem of high loss of microstrip line-monolithic gold wire bonding in terahertz band.Meanwhile,several E-plane probe-coplanar waveguide transition structures in different frequency bands are designed,and the corresponding passive structures are assembled and tested by coplanar waveguide-monolithic gold wire bonding.The measured results show that the single-ended insertion loss of coplanar waveguide-monolithic gold wire bonded package structures at 110-170 GHz and 210-270 GHz are 0.45-1.75 dB and 0.9-2.3 dB,respectively.3)For further study of terahertz packaging technology,three amplifier modules using different packaging technologies were designed,which are operating at 66-115 GHz,110-170 GHz,and 210-270 GHz,respectively.The measured and compared results by inverted microstrip transmission line structure,the microstrip line-monolithic gold wire bonding package structure and the coplanar waveguide-monolithic gold wire bonded package structure in different frequencies indicate that these method are feasible,and its correctness has been verified.Among them,the amplifier module based on the inverted microstrip transmission line structure package has a single-ended package loss within 1.1 dB from 120 to 170 GHz.To our best knowledge,the THz amplifier module packaged using inverted microstrip line structure is also reported for the first time in the existing literature.