Integrated RF Filter Structure for Low Microwave Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional radio frequency chips in mobile phones face challenges with large volume, high power consumption, and parasitic parameter changes due to discrete devices, which are difficult to integrate into miniaturized, high-performance, and consistent components, with Si-based devices having high microwave loss and GaAs-based devices being expensive.
Innovation Solution
A filter design incorporating a dielectric substrate with integrated inductors and capacitors, featuring a buffer layer and connection vias, and conductive structures to form a coil structure, enhancing adhesion and preventing substrate expansion under high temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If Si-based substrates are used for integrated passive devices, then the device price is low, but microwave loss is high due to trace impurities
Solution Approach 1:
The patent uses a composite substrate structure combining SiO2 layer and glass epoxy layer. The SiO2 layer provides low dielectric loss for microwave signal transmission, while the glass epoxy layer provides mechanical strength and cost-effectiveness. This composite approach resolves the contradiction by achieving low microwave loss without using expensive GaAs substrates.
2Reliability
If GaAs-based substrates are used for integrated passive devices, then performance is excellent, but device price is high
Solution Approach 1:
The patent employs a composite substrate of SiO2 and glass epoxy that achieves performance comparable to GaAs substrates through optimized dielectric properties and conductor configuration, while maintaining the cost advantages of conventional materials. The low-loss SiO2 layer compensates for the higher cost of GaAs, delivering excellent performance at lower price.
Solution Approach 2:
The patent optimizes key parameters including dielectric constant, loss tangent, conductor thickness, and trace geometry to achieve high-performance filtering characteristics on cost-effective substrates. By carefully controlling these parameters, the design attains GaAs-level performance on economical substrate materials.
3Adaptability or versatility
If discrete devices are used in traditional mobile phones, then various functions can be implemented, but volume is large and power consumption is high
Solution Approach 1:
The patent integrates multiple passive components (inductors, capacitors, resistors) and filtering functions into a single planar filter structure on the substrate. This consolidation eliminates the need for multiple discrete components, reducing volume and power consumption while maintaining full functionality for RF signal processing.
Solution Approach 2:
The patent transitions from three-dimensional discrete component assembly to two-dimensional planar integration. By laying out inductors, capacitors, and interconnections in a planar configuration on the substrate, the design achieves high functionality in a compact footprint, enabling miniaturization for modern mobile devices.
4Adaptability or versatility
If discrete devices are used on RF PCB, then multiple functions are provided, but parasitic parameter change is large
Solution Approach 1:
The patent combines multiple passive elements into a single integrated filter structure with controlled interconnections. This integration minimizes parasitic inductances and capacitances that arise from multiple discrete component mounts and interconnecting traces, ensuring stable and consistent electrical characteristics across operating conditions.
Data Source
AI summary
A filter, a method for manufacturing a filter and an electronic apparatus are provided, and belongs to the field of passive device technology. The filter includes a dielectric substrate, and at least one inductor and at least one capacitor integrated thereon. The dielectric substrate includes first connection vias penetrating through the dielectric substrate in a thickness direction thereof, and opposite first and second surfaces in the thickness direction. Each inductor includes first and second conductive structures respectively on the first and second surfaces, and first connection electrodes in the first connection vias. The first conductive structures and the second conductive structures form a coil structure of the inductor by the first connection electrodes. A buffer layer is provided between the first conductive structures and the first surface. Each first conductive structure is electrically connected to the first connection electrode by a second connection via penetrating through the buffer layer.