Multi-Zone Heater Temperature Estimation for Substrate Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor equipment heaters are limited to one or two temperature sensors, making it difficult to measure and control the temperature of each zone, which affects process uniformity and requires extensive temperature tuning time.
Innovation Solution
A method using a correlation formula and Kalman filter to estimate the temperature of each zone of the heater based on measured parameters such as power, resistance, and current, without installing additional sensors, and utilizing a database and regression analysis to calculate coefficients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple temperature sensors are installed in each zone of the heater, then the temperature measurement precision of each zone is improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent uses a single temperature sensor to measure the temperature of one zone, then creates virtual copies of this measurement through mathematical modeling and machine learning algorithms to estimate temperatures in other zones. This avoids installing multiple physical sensors while achieving the effect of multi-zone temperature monitoring.
Solution Approach 2:
The patent replaces the mechanical approach of installing multiple physical temperature sensors with a computational approach using machine learning models, correlation formulas, and algorithms to estimate temperatures in multiple zones from a single sensor measurement, thereby reducing hardware complexity.
2Device complexity
If ratio control is used for other zones based on controllable zone output, then the device complexity is reduced, but the temperature measurement precision and process uniformity deteriorate
Solution Approach 1:
Instead of simple ratio control, the patent creates accurate virtual copies of temperature measurements in all zones through machine learning models that learn the complex relationships between heater zone temperatures, allowing precise temperature estimation without additional physical sensors.
Solution Approach 2:
The patent transforms the temperature control approach by using machine learning models that dynamically adjust temperature estimates based on multiple parameters including heater power ratios, thermal conductivity, specific heat, and learned correlations from training data, rather than simple fixed ratio control.
3Stability of the object's composition
If extensive temperature tuning is performed to achieve uniform temperature distribution, then the temperature uniformity is improved, but the productivity and equipment utilization rate deteriorate
Solution Approach 1:
The patent performs preliminary temperature modeling and machine learning training during the setup phase to create accurate predictive models of heater zone temperatures. Once trained, these models enable rapid temperature estimation and adjustment without requiring extensive iterative tuning during actual semiconductor processing, thereby improving productivity.
Solution Approach 2:
The patent implements a feedback mechanism where the single temperature sensor provides real-time temperature measurements that are fed into the machine learning model, which then predicts temperatures in all zones and provides feedback for adjustments, enabling rapid convergence to uniform temperature distribution without extensive manual tuning.
4Device complexity
If only one or two temperature sensors are installed in the heater, then the device complexity is reduced, but the temperature measurement precision of each zone deteriorates
Solution Approach 1:
The patent uses a single physical temperature sensor to measure one zone's temperature, then creates virtual measurements for all other zones through machine learning models that learn the thermal relationships between zones, effectively copying the measurement capability without additional physical sensors.
Solution Approach 2:
The patent makes a single temperature sensor serve multiple functions by using it to measure one zone's temperature while simultaneously providing data that enables estimation of temperatures in all other zones through the machine learning model, thereby achieving multi-zone monitoring with single-sensor hardware.
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
Enables precise temperature control of each zone, improving process uniformity and reducing temperature tuning time, thereby enhancing semiconductor processing precision.
Implementation Method 1
heaters used in semiconductor equipment are multi-zone, that is, composed of a plurality of zones (each zone has a heating wire installed independently)
Data Source
AI summary
According to an embodiment of the present invention, a method for processing a substrate through a heater that heats the substrate to perform a semiconductor process, the method comprising: inputting, into a correlation formula of at least one independent variable, which is a parameter related to the heater, and a dependent variable including a measured temperature of the heater, a measurement value corresponding to the independent variable, and calculating a predicted temperature of the heater; and applying a Kalman filter to the predicted temperature to calculate an estimated temperature.


