Ceramic Mounting Table Joint Structure for High-Temperature Brazing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing mounting table structures in semiconductor processing apparatuses face issues with thermal diffusion of metal elements like cobalt and nickel, leading to brittle intermetallic compound formation and joint strength reduction, particularly at high temperatures during heat treatments.
Innovation Solution
A mounting table structure is designed with a ceramic body, a high-melting-point connection terminal, and a stress relaxing member made from materials free from cobalt and nickel, using a brazing material to prevent thermal diffusion, and optionally incorporating boundary layers or intermetallic compounds for enhanced diffusion blocking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If a stress relaxing member containing cobalt or nickel is used to absorb thermal expansion stress, then stress relaxation is improved, but thermal diffusion occurs leading to brittle intermetallic compound formation and joint strength reduction
Solution Approach 1:
A diffusion barrier layer is introduced as an intermediary between the stress relaxing member and the connection terminal. This barrier layer prevents thermal diffusion of metal elements while allowing the stress relaxing member to continue absorbing thermal expansion stress. The barrier layer acts as a mediator that blocks harmful diffusion paths while maintaining the functional integrity of the joint structure.
Solution Approach 2:
The joint structure is designed as a composite system comprising multiple materials with complementary properties: a stress relaxing member for absorbing thermal stress, a diffusion barrier layer for preventing thermal diffusion, and brazing material for joining components. This composite structure resolves the contradiction by combining materials that individually address different aspects of the problem.
2Productivity
If high-temperature processing is performed to achieve desired circuit devices, then productivity is improved, but thermal diffusion of metal elements occurs causing joint detachment
Solution Approach 1:
The diffusion barrier layer serves as a protective intermediary that enables high-temperature processing by blocking thermal diffusion paths. This allows the processing chamber to reach high temperatures for efficient semiconductor manufacturing while the barrier layer prevents metal element diffusion that would otherwise cause joint detachment.
Solution Approach 2:
The diffusion barrier layer is prepared in advance during the manufacturing process, creating a protective interface before high-temperature processing begins. This preliminary protective measure ensures that subsequent high-temperature processing can proceed without causing thermal diffusion damage to the joint structure.
3Ease of manufacture
If brazing material containing nickel is used to join components, then ease of manufacture is improved, but thermal diffusion of nickel occurs leading to intermetallic compound formation
Solution Approach 1:
The diffusion barrier layer is positioned between the brazing material and the connection terminal to prevent thermal diffusion of nickel from the brazing material. This intermediary layer allows the use of nickel-containing brazing materials for ease of manufacture while protecting the connection terminal from nickel diffusion that would compromise composition stability.
Solution Approach 2:
The diffusion barrier layer is applied locally at the critical interface where thermal diffusion occurs. This localized protection allows nickel-containing brazing materials to be used in areas where ease of manufacture is prioritized, while the barrier layer provides composition stability at the specific interface susceptible to thermal diffusion.
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 configuration effectively prevents thermal diffusion and maintains joint strength, ensuring reliable electrical connectivity and mechanical stability even at high temperatures, reducing the risk of detachment and brittleness in the joint areas.
Implementation Method 1
a stress relaxing member made of a conductive material and interposed between the connection terminal and the power-feeding connector portion to relax a stress
Implementation Method 2
the stress relaxing member and the connection terminal are jointed together by a brazing material
Data Source
AI summary
A mounting table body made of ceramic includes power-receiving conductor portions and buried therein. A surface of mounting table body is formed with a recessed connection hole and a connection terminal electrically jointed to the power-receiving conductor portion and exposed into the connection hole, the connection terminal being made of a high-melting-point metal, an alloy thereof or a compound thereof. A power-feeding line member provided with a power-feeding connector portion is inserted at its leading end portion into the connection hole to feed electricity to the power-receiving conductor portion. A stress relaxing member is interposed between the connection terminal and the power-feeding connector portion. The stress relaxing member and the connection terminal are jointed together by a brazing material. The stress relaxing member is made of a metal free from cobalt and nickel or an alloy thereof.