Ceramic Heater Wire Connection Terminal for Shrinkage Stress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ceramic heaters used in semiconductor manufacturing face breakage issues due to the inability of molybdenum wire conductive connecting portions to follow dry shrinkage during the mold casting process, leading to stress on the ceramic molded body.
Innovation Solution
A ceramic heater design featuring a conductive connection terminal with a first hole for the wire line and a second hole for the outer-peripheral-side resistance heating element, allowing for movement and reducing stress, along with a manufacturing method that includes forming and hot-press firing to minimize breakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a molybdenum wire is used as a conductive connecting portion in a mold casting process, then electrical conductivity is achieved, but the wire cannot follow dry shrinkage of the ceramic molded body causing stress and breakage
Solution Approach 1:
The conductive connecting portion is divided into multiple segments (first conductive portion, second conductive portion, third conductive portion) that can independently deform during dry shrinkage. This segmentation allows each segment to accommodate dimensional changes of the ceramic molded body without generating excessive stress, thereby preventing breakage while maintaining electrical conductivity throughout the connection path.
Solution Approach 2:
The conductive connecting portion is designed with dynamic flexibility rather than rigid fixation. The wire is allowed to change its configuration and follow the dimensional changes of the ceramic molded body during drying and firing processes. This dynamic adaptation enables the conductive connection to maintain integrity despite the shrinkage and deformation of the ceramic structure.
2Reliability
If the wire line is fixed rigidly to the ceramic plate, then connection stability is improved, but stress concentration occurs during drying causing breakage
Solution Approach 1:
The conductive connecting portion transitions from a rigid fixed connection to a dynamic flexible connection. The wire is positioned to follow the deformation of the ceramic molded body during drying, allowing it to adapt to dimensional changes without generating stress concentration points that would lead to breakage.
Solution Approach 2:
The physical state and configuration parameters of the conductive connecting portion are changed to accommodate the drying process. The wire's position and shape are allowed to change in response to the ceramic molded body's shrinkage, transforming the connection from a static rigid structure to a dynamic adaptable one that maintains strength throughout the manufacturing process.
3Strength
If the conductive connecting portion follows dry shrinkage, then stress is reduced, but precise positioning becomes difficult
Solution Approach 1:
The conductive connecting portion is segmented into multiple sections that can independently deform. This segmentation allows the wire to follow the overall shrinkage pattern of the ceramic molded body while maintaining precise positioning at critical connection points such as terminals and heating element interfaces.
Solution Approach 2:
The positioning strategy changes from fixed rigid positioning to controlled flexible positioning. The conductive connecting portion's configuration parameters are allowed to change in response to drying shrinkage, while its endpoint positions at terminals and heating elements are maintained with precision through the flexible path adaptation.
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
The solution effectively suppresses breakage of the ceramic plate by allowing the wire line and resistance heating element to move within their respective holes, reducing stress and preventing cracks, while enabling independent control of heating zones for efficient temperature management.
Implementation Method 1
there is a possibility that, in a step of drying the ceramic molded body that has been formed by the mold casting process, the conductive connecting portion made of the molybdenum wire cannot follow dry shrinkage of the molded body
Implementation Method 2
a conductive connection terminal including a first hole into which the linear portion of the wire line is inserted, and a second hole into which an end portion of the outer-peripheral-side resistance heating element is inserted
Implementation Method 3
an inner-peripheral-side resistance heating element and an outer-peripheral-side resistance heating element are embedded in a ceramic base
Data Source
AI summary
A ceramic heater includes a ceramic plate. An outer-peripheral-side resistance heating element is disposed in an outer peripheral zone of the ceramic plate. A wire line extends from each of a pair of terminals disposed in a central portion of the ceramic plate toward the outer peripheral zone, and a portion of the wire line close to the outer peripheral zone is a linear portion. A connection terminal is a conductive member connecting between the wire line and the outer-peripheral-side resistance heating element, and includes a first hole into which the linear portion of the wire line is inserted and a second hole into which an end portion of the outer-peripheral-side resistance heating element is inserted.