Resist Coating Atmosphere Control for Linewidth Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor manufacturing, the dispersion in linewidth dimension of resist patterns formed during the photolithography process leads to variations in etched shapes and ion-implanted regions, affecting the reliability and yield of semiconductor devices, particularly when different types of chemical amplification type photoresists are used in the same manufacturing line.
Innovation Solution
A process and apparatus that change the atmosphere surrounding the substrate whenever lots or photoresist types change, ensuring stable heat treatment by removing residual solvent elements from previous lots, and using adjustable exhaust systems to maintain optimal chamber conditions, thereby minimizing dimensional variations in resist patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If different types of chemical amplification type photoresist are processed in the same manufacturing line without atmosphere change, then productivity is maintained, but manufacturing precision deteriorates due to linewidth dimension variation
Solution Approach 1:
The atmosphere in the heat treatment chamber is changed in advance before processing a new lot of photoresist, by comparing the type with the previously processed photoresist. This preliminary atmosphere change prevents contamination from residual solvents of the previous photoresist type, ensuring that linewidth dimension precision is maintained while allowing continuous processing of different photoresist types without extended idle time.
2Manufacturing precision
If atmosphere change is performed whenever photoresist type changes, then manufacturing precision is improved, but loss of time increases due to atmosphere change operations
Solution Approach 1:
The system implements a feedback mechanism by comparing the photoresist type of the current lot with the previously processed lot. The atmosphere change operation is conditionally executed only when the photoresist type changes, as determined by this comparison. This feedback-controlled approach minimizes unnecessary atmosphere changes, reducing time loss while ensuring precision is maintained when needed.
3Productivity
If heat treatment is performed continuously without photoresist type comparison, then productivity is maintained, but reliability deteriorates due to chemical influence from residual solvents
Solution Approach 1:
The system extracts and identifies the photoresist type information from the process data, comparing it with the previously processed photoresist type. When a type change is detected, the atmosphere change operation is triggered to remove residual solvent components from the previous photoresist. This extraction and comparison mechanism ensures that chemical influences from residual solvents are eliminated, maintaining reliability while allowing continuous processing.
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 significantly reduces dimensional variations in resist patterns, enhances the reliability of semiconductor circuits, and maintains energy efficiency and cost-effectiveness by ensuring stable and controlled heat treatment processes.
Implementation Method 1
the abovementioned heat treatment process by the baking apparatus is provided for example between the exposure process and the development process. By heat treating after exposure, acid contained in the photoresist is diffused to form a latent image on the resist
Data Source
AI summary
A process for forming a resist pattern according to the invention is a process for forming a resist pattern in which a photoresist is coated on a first substrate, the coated photoresist is exposed to light of a predetermined pattern, and afterwards developing is performed, wherein in at least one of the processes of coating, exposing, and developing, whenever lots to which the first substrate belongs change, the atmosphere residing in the lot is changed.