Research On Band-pass Filter Based On TGV Technology

Widthband Filter was increasing demanded for high performance computing,fifth-generation(5G)communication,and Internet of Things(IOT)applications.Higher requirements have been placed on the performance of filter substrates,such as lower high-frequency losses and higher aspect ratios of vertical interconnect vias.Glass is an ideal substrate material due to its excellent insulating properties,large panel availability and a coefficient of thermal expansion(CTE)matched silicon.It is an ideal substrate material for microwave passive integrated devices(IPD).Meanwhile,the use of TGV interposer can avoid complex manufacturing processes and expensive equipment,which will further reduce costs.The interdigitated band-pass filter has a compact structure,high selectivity and good stop-band attenuation at the cutoff frequency,which is suitable for the design of broadband band-pass filter.Due to the large spacing between the resonator elements,the manufacturing tolerances are relatively loose.In this thesis,a ninth-order asymmetric coupled interdigital band-pass filter design based on TGV technology was proposed.The physical structure of the filter was obtained by combining theoretical calculation and high-frequency software simulation.The filter was fabricated on Schott AF32 glass wafer.Firstly,the basic design principle of microstrip band-pass filter was introduced.According to the performance index of the filter,the Chebyshev low-pass prototype filter wass selected for frequency conversion.Through the design of asymmetric coupling filter with the same resonator width,the X-band broadband band-pass filter based on TGV is optimized.The experimental scheme of TGV filter was explored,the optimal process parameters were determined,and the physical fabrication of interdigital band-pass filter based on TGV was carried out:the small-size physical fabrication of RF devices was realized by combining micromachining technology with glass substrate;The combination of advanced laser drilling and through-hole corrosion technology was adopted to achieve a diameter of 50?m TGV process with high aspect ratio;The difficult glass through-hole metallization process was completed by electroplating and deep hole sputtering.Finally,the band-pass filter based on TGV technology was tested by using the principle of coplanar waveguide detection(CPW).The center frequency of the filter is9.8GHz and the pass-band bandwidth is 4.5GHz,insertion loss in passband lass than1d B,the out of band suppression is less than-50d B,and the total area of the fabricated device is 25.24mm~2.The tested results show that the performance of the measured filter performance was basically the same as the simulation.The application of glass substrates in radio frequency devices was realized,which proves that glass and silicon processes can be well compatible.A wideband band-pass filter with small overall device size,low loss and strong out-of-band suppression was fabricated within the allowable range of fabrication errors.