The Research Of TaN Thin Film And Microwave Integrated Load, Isolator In Ferrite Substrate

Microwave devices and load of integration is the development direction in the fieldof application and hotspot issues, and integrated microwave gyromagnetic ferritesubstrate film and through the lithography technology to realize the integration of themicrowave devices is the application of urgent needs. Based on this background, first ofall, this paper developed ferrite substrate TaN thin film material, solve the resistivity,power density and so on. Then design load of microwave and microwave isolator,optimized parameters, the last successful preparation of DC to20GHZ microwave loadand isolator.Firstly, produce TaN film in the ferrite substrate by DC sputtering method, studyhow the different sputtering pressure, different nitrogen flow, different annealingtemperature on the film influent the phase structure, sheet resistance and TCR. Then,design the DC-20GHz,1W power resistor by HFSS.Finally,produce a resistor kind of1mm×1mm by photolithography, cutting and other processes.Secondly, experimental results show that:the background vacuum degree5×10-5pa,Ar flow20sccm, N₂flow1sccm, sputtering power of40W, sputtering time20min,sputtering temperature of200℃， annealing temperature600℃is the bestproduction process,the produced films have better stability, low temperature coefficient,the square resistance is40Ω/sq and is suitable for producing resisitance.Thirdly,designing the DC-20GHz,1W power film resistor by HFSSsoftware.Simulated DC-20GHz standing wave ratio （VSWR）<1.2.Then, makingresistance by lithography electrode and the resistive film cutting. Test results as follows:within the scope of the DC to20GHZ frequency standing-wave pattern than the VSWRbasic is less than1.25, the rated power of1w, the resistance changes from48Ω to54Ω.Finally, start the simulation of microwave ferrite isolators and production, firstdesign devices by HFSS.IN frequency of8GHz-13GHz, the return loss is greater than20dB, isolation greater than20dB, VSWR less than1.2.Then, test performance: in8GHz-13GHz frequency band, S11parameter is greater than15dB, input loss is less than4dB, isolation degree greater than13dB, integrated microwave isolatorperformance is not good, but the basic realization of the function of microwaveisolation.