Chip Package Contact Layer Corrosion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Copper (Cu) and silver (Ag) bond wires used in chip packages are prone to oxidation and corrosion, especially under elevated temperatures and in humid environments, leading to weak bonding and mechanical strength loss, which can result in electrical failures before the anticipated end of life.
Innovation Solution
The chip package incorporates a packaging material with a contact layer where the summed concentration of chemically reactive sulfur, selenium, and tellurium is less than 10 atomic parts per million, reducing the risk of corrosion by minimizing the presence of these elements, which are known to cause corrosive reactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If copper or silver bond wires are used instead of gold wire, then cost is reduced, but corrosion resistance deteriorates
Solution Approach 1:
A diffusion barrier layer is introduced as an intermediary between the copper/silver bond wire and the packaging material. This barrier layer prevents corrosive elements (sulfur, selenium, tellurium) from the packaging material from reaching and corroding the metal bond wire, while still allowing the cost-effective copper or silver wire to be used instead of expensive gold wire
Solution Approach 2:
The concentration of chemically reactive sulfur, selenium, and tellurium in the packaging material is strictly controlled to be less than 10 atomic parts per million. By changing the compositional parameters of the packaging material, the corrosiveness toward copper and silver wires is reduced, enabling reliable use of these cost-effective materials
2Quantity of substance
If copper bond wires are used, then cost advantage is achieved, but oxidation resistance deteriorates
Solution Approach 1:
The diffusion barrier layer acts as a protective intermediary that prevents oxygen and other oxidizing agents in the packaging material from reaching the copper bond wire. This allows copper wire to maintain its cost advantage while the barrier layer protects against oxidation that would otherwise occur in ambient conditions
Solution Approach 2:
The packaging material is designed to create an inert environment by strictly limiting the concentration of chemically reactive elements (sulfur, selenium, tellurium to less than 10 atomic parts per million). This inert environment prevents oxidation and corrosion of the copper bond wire, maintaining stability without requiring expensive gold alternatives
3Ease of manufacture
If packaging material with standard composition is used, then manufacturing simplicity is maintained, but corrosion protection deteriorates
Solution Approach 1:
The packaging material composition is optimized by controlling the concentrations of specific elements (sulfur, selenium, tellurium less than 10 atomic parts per million) while maintaining standard manufacturing processes. This parameter control provides corrosion protection without significantly complicating the manufacturing process
Solution Approach 2:
A diffusion barrier layer is incorporated into the packaging structure as an intermediary protective element. This layer is integrated into the existing packaging material system and provides corrosion protection through its inherent barrier properties, maintaining manufacturing simplicity while dramatically improving corrosion resistance
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 significantly reduces corrosion and extends the operational life of the chip package by preventing corrosive attacks on metal surfaces, ensuring reliable electrical connections and mechanical integrity.
Implementation Method 1
Copper (Cu) and silver (Ag) bond wires used in chip packages are prone to oxidation and corrosion, especially under elevated temperatures and in humid environments
Implementation Method 2
Copper (Cu) and silver (Ag) bond wires used in chip packages are prone to oxidation and corrosion
Data Source
AI summary
In various embodiments, a chip package is provided. The chip package may include a chip including a chip metal surface, a metal contact structure electrically contacting the chip metal surface, and packaging material including a contact layer being in physical contact with the chip metal surface and/or with the metal contact structure; wherein at least in the contact layer of the packaging material, a summed concentration of chemically reactive sulfur, chemically reactive selenium and chemically reactive tellurium is less than 10 atomic parts per million.