Spiral Inductor Edge Projections for RF Stability

The patent applies local quality by adding projections only at specific locations (edges and corners) of the spiral inductor traces rather than uniformly across the entire structure. These localized projections create distributed capacitance that reduces the Q factor, while the majority of the trace maintains its original conductive path for low DC resistance. This resolves the contradiction by locally modifying the structure to achieve stability without compromising overall manufacturability.

The inductor structure is segmented by adding discrete projections at various positions along the spiral traces. These projections act as separate capacitive elements that are distributed throughout the inductor structure. The segmentation approach allows the inductor to maintain its basic spiral geometry for easy manufacturing while introducing distributed capacitance through the segmented projections to reduce Q factor and improve stability.

The projections are strategically placed at edges and corners where they provide capacitive coupling to reduce Q factor, while the main trace width and thickness are maintained to preserve low DC resistance. This localized modification approach ensures that the impedance reduction benefit is achieved without significantly increasing the DC resistance, thus resolving the contradiction between stability and voltage degradation.

The patent changes the geometric parameters of the inductor by adding projections with specific dimensions (height, width, spacing) that optimize the balance between Q factor reduction and DC resistance maintenance. By carefully controlling these parameters, the design achieves the desired stability improvement while minimizing the impact on DC resistance and voltage degradation.