Carbon Nanofiber Package Capacitors for High-Density Power Delivery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current integrated circuit (IC) packages face challenges in achieving high capacitance density due to limitations in existing capacitor form factors, such as metal-insulator-metal (MIM) and multi-layer ceramic capacitors, which struggle to support increasing power delivery needs and processor operating frequencies.
Innovation Solution
The integration of carbon nanofiber capacitors within package substrates, utilizing high aspect ratio carbon nanofibers to achieve high capacitance densities of up to 650 nanofarad per square millimeter with low equivalent series resistance, by adjusting the aspect ratio and spacing of carbon nanofibers to optimize capacitance and mechanical strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If traditional capacitor form factors (MIM, multi-layer ceramic) are used, then device structure is simple and manufacturing is mature, but capacitance density is insufficient and power delivery capability is limited
Solution Approach 1:
The patent transitions from planar capacitor structures to three-dimensional vertical structures by growing carbon nanofibers perpendicular to the substrate surface. This dimensional change enables significantly higher capacitance density by utilizing the vertical space above the substrate, achieving up to 650 nF/mm² compared to traditional planar capacitors.
Solution Approach 2:
The patent employs composite material structures consisting of carbon nanofibers grown on catalytic metal layers (such as nickel or cobalt), with subsequent deposition of dielectric materials and conductive contacts. This composite approach combines the high surface area of nanofibers with the functional properties of different materials to achieve both high capacitance and mechanical robustness.
2Quantity of substance
If carbon nanofiber aspect ratio is increased to achieve higher capacitance density, then capacitance improves, but mechanical strength decreases
Solution Approach 1:
The patent systematically varies the aspect ratio of carbon nanofibers by controlling growth parameters such as deposition time, temperature, and catalyst particle size. By optimizing these parameters, the patent achieves the desired balance between capacitance density (which increases with aspect ratio) and mechanical strength (which decreases with aspect ratio), targeting an optimal range for power delivery applications.
Solution Approach 2:
The patent addresses mechanical strength concerns by incorporating support structures and optimizing the base layer configuration before the nanofiber growth process. The catalytic metal layer and underlying substrate are designed to provide mechanical support to the high-aspect-ratio nanofibers, preventing structural failure while maintaining the vertical morphology needed for high capacitance.
3Quantity of substance
If carbon nanofiber spacing is reduced to increase capacitance density, then capacitance improves, but equivalent series resistance increases
Solution Approach 1:
The patent implements non-uniform spacing patterns of carbon nanofibers, with denser regions optimized for capacitance and spaced regions optimized for low resistance. The local density of nanofibers is varied across the capacitor structure to simultaneously achieve high capacitance density and low equivalent series resistance, rather than using uniform spacing throughout.
Solution Approach 2:
The patent reduces equivalent series resistance by creating conductive pathways in the vertical dimension through the nanofiber structures and conductive contacts. This three-dimensional conductive network provides multiple parallel paths for current flow, reducing resistance even when horizontal spacing between nanofibers is reduced to increase capacitance density.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables increased capacitance density and reduced power loss, allowing for more efficient power delivery and improved mechanical robustness in IC packages, addressing the limitations of traditional capacitor form factors.
Implementation Method 1
carbon nanofiber capacitors within package substrates, utilizing high aspect ratio carbon nanofibers to achieve high capacitance densities of up to 650 nanofarad per square millimeter with low equivalent series resistance
Data Source
AI summary
Carbon nanofiber capacitor apparatus and related methods are disclosed herein. An example apparatus includes an integrated circuit package substrate, and a capacitor provided in the integrated circuit package substrate. The capacitor includes a carbon fiber array, a dielectric film positioned on the carbon fiber array, and an electrode film positioned on the dielectric film.