Plasma Etching Substrate Temperature Control for CD Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current plasma etching systems face challenges in achieving uniformity and repeatability in semiconductor substrate processing due to temperature control difficulties, which can lead to non-uniformity in critical dimensions, affecting device yield.
Innovation Solution
A plasma etching system with a substrate support assembly featuring independently controllable heater zones and a controller unit that measures and adjusts temperatures at specific locations on the substrate based on pre-etch and post-etch critical device parameters to maintain target etching temperatures, ensuring radial and azimuthal temperature control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If plasma etching is performed on semiconductor substrates with increasing substrate diameter and decreasing transistor size, then productivity and device density are improved, but manufacturing precision and uniformity of critical dimensions deteriorate
Solution Approach 1:
The substrate support assembly is divided into multiple independently controllable heater zones (first, second, third, and fourth heater zones) positioned at different radial locations. Each heater zone can be controlled separately to achieve precise local temperature management across the substrate surface, thereby maintaining critical dimension uniformity while processing larger substrates.
Solution Approach 2:
Different radial regions of the substrate are subjected to different temperature profiles through the independently controllable heater zones. The system applies local quality control by adjusting temperature at specific radial positions to compensate for non-uniform heating effects, ensuring consistent etching results across the entire substrate surface.
2Ease of operation
If substrate temperature is not uniformly controlled during plasma etching, then ease of operation is improved, but manufacturing precision and critical dimension uniformity deteriorate
Solution Approach 1:
The heater zones are designed to be independently and dynamically controllable, allowing the system to adapt temperature profiles in real-time based on processing requirements. The controller unit adjusts the heating power of each zone dynamically to maintain uniform substrate temperature despite variations in plasma conditions, substrate position, or process parameters.
Solution Approach 2:
The system incorporates a controller unit that monitors and adjusts the heating of each zone based on feedback from process parameters and temperature measurements. This closed-loop control ensures that temperature uniformity is maintained across the substrate surface, compensating for any deviations that occur during the etching process.
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 approach enhances the uniformity and consistency of the plasma etching process, improving the critical dimension uniformity and device yield by actively managing temperature profiles across the substrate.
Implementation Method 1
a plurality of independently controllable heater zones in an arrangement under device die locations on the substrate
Implementation Method 2
plasma etching the substrate
Data Source
AI summary
A plasma etching system having a substrate support assembly with multiple independently controllable heater zones. The plasma etching system is configured to control etching temperature of predetermined locations so that pre-etch and/or post-etch non-uniformity of critical device parameters can be compensated for.