Lithographic Patterning Verification via Acoustic Scanning Probe Microscopy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current nanolithography methods cannot verify critical dimensions and detect defects until after the development step, making it impossible to correct any issues found, resulting in potential loss of semiconductor elements during fabrication.
Innovation Solution
Incorporating an acoustic scanning probe microscopy step before development to measure local contact stiffness and verify chemical modifications in the resist material, allowing for timely detection and correction of defects and critical dimension errors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the development step is performed before verification, then the patterning process can be completed, but defects and critical dimension errors cannot be detected until after development, making correction impossible
Solution Approach 1:
The patent applies preliminary action by performing the verification step (acoustic scanning probe microscopy) before the development step. This allows detection of defects and critical dimension errors in the chemically modified resist material before the resist is removed, enabling timely correction of patterning errors and preventing loss of semiconductor elements.
2Reliability
If the verification step is added before development, then defect detection and correction capability is improved, but the process complexity increases
Solution Approach 1:
The patent introduces an intermediary verification step using acoustic scanning probe microscopy that acts as a mediator between the exposure and development steps. This intermediary step provides non-destructive verification of patterning quality without requiring the removal of the resist layer, thus adding verification capability while maintaining process flow.
3Measurement precision
If acoustic scanning probe microscopy is used to measure contact stiffness, then critical dimensions can be measured before development, but the measurement process adds time to the fabrication cycle
Solution Approach 1:
The patent replaces traditional mechanical measurement methods with acoustic scanning probe microscopy that uses acoustic waves to measure contact stiffness. This substitution enables non-contact or minimal-contact measurement of critical dimensions through acoustic property changes, providing high measurement precision while being compatible with the resist material in situ before development.
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 the verification of patterning accuracy and correction of defects before the development step, preventing semiconductor element loss and improving manufacturing yield.
Implementation Method 1
scanning at least a part of the surface using an acoustic scanning probe microscopy method for determining a local contact stiffness of the substrate surface
Implementation Method 2
determining a local contact stiffness of the substrate surface at a plurality of locations, for measuring one or more critical dimensions of the features
Data Source
AI summary
The present document describes a lithographic patterning method for creating features on a surface of a substrate. The patterning method includes the steps of applying a resist material to the substrate surface for providing a resist material layer, selectively exposing, dependent on a location and based on patterning data, the resist material layer to a surface treatment step for chemically modifying the resist material of the resist material layer, and developing, based on the chemical modification of the resist material, the resist material layer such as to selectively remove the resist material. In particular, prior to the step of developing, the method comprises a step of scanning at least a part of the surface using an acoustic scanning probe microscopy method for determining a local contact stiffness of the substrate surface at a plurality of locations, for measuring one or more critical dimensions of the features to be formed on the surface.