Semiconductor Overlay Detection Using Luminescent Hole Regions
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Solution Overview
Problem
Current methods fail to accurately detect overlay errors in high aspect ratio holes or trenches using secondary electrons, such as those detected by a scanning electron microscope, due to the limitations in positioning practical positions of these features.
Innovation Solution
A semiconductor device is designed with luminescent material-based detection regions on a substrate, allowing for the determination of overlay errors by emitting a luminescent signal when an electron beam interacts with these regions, enabling precise positioning of holes with high aspect ratios through fluorescence microscopy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If secondary electron detection is used to detect overlay errors, then the detection method is simple and widely applicable, but the detection precision deteriorates for high aspect ratio holes
Solution Approach 1:
The patent introduces a luminescent material as an intermediary between the electron beam and the detection system. When the electron beam excites the luminescent material in the detection region, it emits light that can be detected with high precision. This intermediary converts the interaction into a detectable optical signal, solving the problem of poor detection precision for high aspect ratio holes while maintaining ease of manufacture
Solution Approach 2:
The patent replaces the mechanical/physical secondary electron detection system with an optical detection system based on luminescence. Instead of detecting secondary electrons directly, the system uses luminescent materials that emit light when excited by the electron beam, allowing optical detectors to measure the position with high precision. This substitution overcomes the limitations of secondary electron detection for high aspect ratio structures
2Productivity
If the holes have high aspect ratio to increase storage capacity, then the device functionality is improved, but the ability to detect overlay errors deteriorates
Solution Approach 1:
The luminescent material serves as a mediator that enables precise position detection even for high aspect ratio holes. The material is disposed in the detection region at the bottom of the hole, and when excited by the electron beam, it emits light that provides a clear positional signal regardless of the hole's aspect ratio, thus maintaining detection capability while allowing high aspect ratio holes for increased storage capacity
Solution Approach 2:
The patent applies local quality by placing the luminescent material specifically in the detection region at the bottom of each hole, rather than uniformly throughout the structure. This localized placement ensures that the luminescent material provides positional information exactly where needed (at the hole bottom), enabling precise overlay error detection for high aspect ratio holes without affecting the overall hole geometry required for storage capacity
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 allows for the successful detection of overlay errors in high aspect ratio holes, overcoming the limitations of secondary electron detection and providing accurate positioning for further processing, such as filling pillars placement.
Implementation Method 1
one of the plurality of detection regions includes a luminescent material... providing an electron beam propagating toward the plurality of detection regions to emit a luminescent signal from one of the plurality of detection regions
Data Source
AI summary
A semiconductor device includes a substrate and an overlapping layer disposed on the substrate body. The substrate has a substrate body and a plurality of detection regions disposed on a top surface of the substrate body, in which one of the plurality of detection regions includes a luminescent material. The overlapping layer has a plurality of holes, and each one of the plurality of detection regions corresponds to each one of the plurality of holes. A method of manufacturing a semiconductor device is further provided.