Research On Key Technologies Of 220GHz InP Solid-state Amplifier

Terahertz is a hot subject involving optics field and electronics field.Terahertz science has been used in satellite communications and security inspections own to its excellent advantages similar to light waves and microwaves.In order to find the potential value of terahertz,the research institutions have begun to carry out related research work.The domestic 220 GHz amplification technology is still in the developing stage.This paper studies the key technologies of the 220 GHz solid-state amplifier circuit,including the design and packaging technology of the terahertz amplifier.This paper introduces the design of three 220 GHz amplifier monolithic.The wavelength of 220 GHz is so short that the uncertainty of manual operation cannot be avoided in the packaging process,which makes the 220 GHz packaging technology have high loss and instability.In order to reduce the assembly error,this paper employs an approach that the dipole antenna transition is integrated with the amplifier circuit based on the 0.5 ?m InP HBT process.The chip circuit adopts a one-way eight-stage common emitter structure.The simulation results indicate that small signal gain is greater than 15 dB between 210 GHz and 230 GHz.In order to realize on-chip testing,the second single chip was designed with the RF pad.The simulation results show that the small signal gain of 210-230 GHz is greater than 17 dB,the power gain is about 15 dB and the saturated output power is 4.9dBm at 220 GHz.The structure can be tested on the chip to verify the first monolithic circuit.To improve the output power,a four-way six-stage amplifier monolith is designed using combiner structure.The simulation results show that the small signal gain of 210-230 GHz is 11-14 dB,and the saturated output power of 220 GHz is more than 10 dBm.To further study the 220 GHz packaging technology,a broadband E-plane probe transition structure is designed,which adopts a structure such as tapper microstrip line and tapper waveguide.The measured results show that of the insertion loss of the single transition is better than 1dB between 170 GHz and 240 GHz.The transition is used for a 220 GHz InP HEMT amplifier chip with gold wire to connect the transition to core IC.Finally,The measured results that the gain is 11-17 dB at 210-230 GHz and noise figure is 7.5-12 dB at 216-230 GHz.To avoid the employment of gold wire during the interconnection process,the paper employs flip-suspended-coplanar-waveguide transition structure and replaces active chip by 50? quartz transmission line.Then the passive structure is assembled and measured,and the final measured data is that the insertion loss of single transition at 220 GHz is about 2.5dB.