Through-Substrate Via Alloy Composition for Strength and Conductivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Microelectronic packaging components with low-purity wiring materials face increased resistivity and mechanical weakness due to impurities, leading to performance issues and failure from heat cycling and thermal expansion, necessitating a balance between resistivity and mechanical strength.
Innovation Solution
A component with conductive elements made from an alloy of copper, aluminum, nickel, or chromium, combined with additives like Gallium, Germanium, Indium, Selenium, Tin, Sulfur, Silver, Phosphorus, or Bismuth, where the additive concentration is less than 5% of the total atomic mass, achieving a resistivity between 2.5 and 30 micro-ohm-centimeters and enhanced mechanical strength through varying alloy composition across the conductive elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If impurities are reduced in wiring materials to decrease resistivity, then electrical performance is improved, but mechanical strength decreases due to increased grain size
Solution Approach 1:
The patent changes the chemical composition parameters by introducing specific alloying elements (silver, gold, platinum, palladium, rhodium, or iridium) at controlled concentrations (0.01-5 atomic percent). This parameter modification allows the material to achieve both low resistivity and high mechanical strength simultaneously, resolving the contradiction between electrical performance and mechanical strength that plagues ultra-pure materials.
Solution Approach 2:
The patent creates a composite material system by combining ultra-pure base metals (copper, aluminum, nickel, or chromium) with trace amounts of noble metal additives. This composite approach leverages the excellent electrical conductivity of the base metal while the noble metal particles act as grain boundary strengtheners, achieving both low resistivity and high mechanical strength through material composition design.
2Reliability
If additional processing is applied to remove impurities, then resistivity is reduced, but grain size increases leading to decreased mechanical strength
Solution Approach 1:
The patent takes out harmful impurities through additional processing while simultaneously introducing beneficial noble metal additives. This extraction and addition strategy allows the material to achieve ultra-low resistivity without the detrimental grain growth that normally accompanies impurity removal, as the noble metal particles pin grain boundaries and prevent excessive grain growth.
Solution Approach 2:
The patent changes the material composition parameters by adding noble metal elements that fundamentally alter the grain growth behavior during processing. This parameter modification allows aggressive impurity removal and grain refinement processing to be applied without resulting in excessive grain growth, thereby achieving both low resistivity and fine grain structure for high mechanical strength.
Data Source
AI summary
A component includes a support structure having first and second spaced-apart and parallel surfaces and a plurality of conductive elements extending in a direction between the first and second surfaces. Each conductive element contains an alloy of a wiring metal selected from the group consisting of copper, aluminum, nickel and chromium, and an additive selected from the group consisting of Gallium, Germanium, Indium, Selenium, Tin, Sulfur, Silver, Phosphorus, and Bismuth. The alloy has a composition that varies with distance in at least one direction across the conductive element. A concentration of the additive is less than or equal to 5% of the total atomic mass of the conductive element, and a resistivity of the conductive element is between 2.5 and 30 micro-ohm-centimeter.