Wafer Stage Heater Control for In-Plane Temperature Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor manufacturing techniques struggle to achieve a target in-plane temperature distribution for wafer processing, leading to impaired processing yield due to heat transfer issues between heater regions and the wafer.
Innovation Solution
A semiconductor device manufacturing system that includes a wafer stage with multiple heaters and a controller to adjust heater power outputs, along with a wafer temperature calculation system that determines whether initial target temperature distributions can be implemented and corrects them to ensure feasible power outputs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the target in-plane temperature distribution is calculated based on the relational expression between wafer temperature and pattern dimension, then the desired pattern uniformity can be achieved, but the heater power output may exceed the allowable range due to heat transfer issues
Solution Approach 1:
The system performs preliminary calculation of the target temperature distribution and heater power outputs before actual wafer processing. It predicts whether the calculated power outputs will be within the allowable range, and if not, corrects the target temperature distribution in advance to ensure implementable power outputs, thereby avoiding processing delays and ensuring pattern uniformity.
Solution Approach 2:
The system incorporates feedback control by comparing the calculated heater power outputs against the allowable range and adjusting the target temperature distribution accordingly. When power outputs exceed limits, the system feeds back corrected temperature distribution values that account for heat transfer characteristics, ensuring both pattern uniformity and implementable power requirements.
2Temperature
If the heater power output is increased to achieve the target temperature distribution, then the desired wafer temperature can be maintained, but processing yield is impaired due to heat transfer limitations
Solution Approach 1:
The system calculates and corrects the target temperature distribution before processing begins, predicting heat transfer effects and adjusting power requirements to remain within allowable ranges. This preliminary correction prevents processing failures and maintains reliability while achieving desired temperature control.
Solution Approach 2:
The system changes the target temperature distribution parameters to account for heat transfer limitations. By adjusting the temperature setpoints based on predicted heat transfer behavior, the system maintains reliable processing within power constraints while still achieving adequate temperature control for pattern formation.
3Reliability
If the target temperature distribution is corrected to ensure implementable power outputs, then processing reliability is improved, but the desired temperature distribution may deviate from the initial target
Solution Approach 1:
The system uses feedback control to balance reliability and precision. When the initial target temperature distribution requires power outputs beyond allowable ranges, the system calculates corrected temperature distributions that optimize both reliability and pattern uniformity. The feedback mechanism ensures that corrections minimize deviation from desired temperature profiles while maintaining implementable power outputs.
Solution Approach 2:
The system adjusts temperature distribution parameters through iterative correction, modifying the target values to account for heat transfer effects and power constraints. These parameter changes are optimized to maintain manufacturing precision for pattern formation while ensuring processing reliability within device capabilities.
4Manufacturing precision
If multiple heaters are used to control in-plane temperature distribution, then temperature uniformity can be improved, but device complexity increases
Solution Approach 1:
The heating system is segmented into multiple independent heater zones, each capable of independent power control. This segmentation enables precise local temperature adjustment across the wafer surface, improving temperature uniformity while allowing the control system to manage complexity through modular zone-based control strategies.
Solution Approach 2:
Different regions of the wafer receive customized heating through locally controlled heater zones. Each heater zone is independently adjusted to provide the specific temperature required for that local region, achieving superior temperature uniformity across the entire wafer while managing system complexity through localized control rather than global adjustment.
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 system prevents the wafer temperature distribution from deviating from the desired temperature, thereby improving processing yield and reducing the likelihood of processing stops.
Implementation Method 1
a plurality of heaters disposed inside the wafer stage and below a plurality of regions of the upper surface... adjust outputs of a plurality of heater power supplies supplied to the plurality of heaters
Data Source
AI summary
A semiconductor device manufacturing system and method for improving processing yield including a semiconductor device manufacturing apparatus including a wafer stage having an upper surface configured to allow the wafer to be placed, a plurality of heaters disposed inside the wafer stage and below a plurality of regions of the upper surface, and a controller configured to adjust outputs of a plurality of heater power supplies supplied to the plurality of heaters; and a wafer temperature calculation system configured to determine whether first output values of the plurality of the heater power supplies calculated in advance to implement a target temperature of the wafer during the processing are within an allowable range, and calculate second output values obtained by correcting all the first output values to values within the allowable range when the first output values are out of the allowable range.