Resistive Heater Thermal Map Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Layered resistive heaters exhibit non-uniform sheet resistance due to manufacturing variations and assembly irregularities, leading to unpredictable thermal distribution and inefficiencies in achieving intended thermal profiles.
Innovation Solution
A method involving the design and manufacturing of baseline and detection circuits with adjustable trace widths and resistivity, using selective removal processes and thermal imaging to iteratively modify the heater circuits to achieve a desired thermal map, allowing for precise adjustment of watt density distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional manufacturing methods are used to produce layered heaters, then production efficiency is maintained, but sheet resistance uniformity deteriorates due to manufacturing variations and assembly irregularities
Solution Approach 1:
The patent applies preliminary action by pre-determining compensation values for sheet resistance variations before the actual heater assembly production. Statistical data from preliminary measurements of substrate sheet resistance is used to calculate compensation values that are stored in memory, enabling automated compensation during production without slowing down the manufacturing process.
Solution Approach 2:
The system implements self-service by automatically measuring substrate sheet resistance, retrieving pre-calculated compensation values from memory, and adjusting heater element parameters without requiring manual intervention. The controller automatically compensates for variations by adjusting the heater elements based on the measured substrate properties, making the system self-correcting.
2Measurement precision
If iterative design modifications are made to achieve desired thermal distribution, then thermal profile precision is improved, but development time increases
Solution Approach 1:
The patent eliminates iterative modifications by pre-calculating compensation values for all possible substrate sheet resistance variations before production. Instead of repeatedly modifying heater designs during development, the system uses statistical data from preliminary measurements to create a comprehensive compensation lookup table that covers the full range of expected variations.
Solution Approach 2:
The system implements feedback by measuring the actual substrate sheet resistance during production, comparing it against the statistical data, and automatically selecting the appropriate pre-calculated compensation values. This closed-loop feedback mechanism ensures thermal profile precision without requiring time-consuming iterative design adjustments.
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 method enables consistent and precise control over thermal profiles by iteratively refining the resistive heater circuits, ensuring uniform thermal distribution across multiple heater assemblies.
Implementation Method 1
a resistive heating layer disposed on the dielectric layer
Implementation Method 2
thermal imaging to iteratively modify the heater circuits to achieve a desired thermal map
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
A method of adjusting a watt density distribution of a resistive heater includes designing a baseline heater circuit. A detection circuit is designed having a constant trace watt density and the detection circuit overlaps the baseline heater circuit. The detection circuit is manufactured, and its baseline thermal map is obtained. The baseline heater circuit is manufactured, and a nominal thermal map is obtained. A subsequent detection circuit is manufactured, and an actual thermal map is obtained. A subtraction thermal image is created by subtracting the baseline thermal map from the actual thermal map, and a subsequent baseline heater circuit is modified according to the subtraction thermal image.