Semiconductor Hole Etching with Protective Layer CD Shrink
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Solution Overview
Problem
The challenge in semiconductor device manufacturing is that small capacitance holes with high depth-to-width ratios cannot be etched effectively, leading to process disruptions, while increasing hole size fails to meet the demand for smaller semiconductor devices.
Innovation Solution
A method involving the formation of a first hole and a second hole, where a protective layer is deposited on the side of the second pattern layer to reduce the critical dimension of the first hole, allowing the second hole to be etched using the second pattern layer and protective layer as a mask, resulting in a smaller hole size that meets the demand for small semiconductor devices without process disruptions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the size of a capacitance hole is reduced to meet the demand for smaller semiconductor devices, then the device size is reduced, but the depth-to-width ratio increases causing etching failures
Solution Approach 1:
The patent divides the single etching process into two sequential etching operations: first etching to form a preliminary hole with larger opening, then second etching to form the final small hole. This segmentation allows each etching step to operate within acceptable depth-to-width ratio limits, preventing etching failures while achieving the desired small final hole size.
Solution Approach 2:
The patent performs a preliminary etching action to create a first hole with controlled dimensions, then uses this first hole as a template for the second etching action. The first hole serves as a pre-prepared structure that guides the formation of the final small hole, ensuring that the etching process remains controllable throughout.
2Manufacturing precision
If the size of a capacitance hole is increased to enable successful etching, then etching quality improves, but the semiconductor device size requirement cannot be met
Solution Approach 1:
The patent segments the hole formation into two distinct stages: the first etching creates a hole with larger opening that is easy to etch through, while the second etching refines it to the required small size. This segmentation allows the process to achieve both good etching quality and small final dimensions.
Solution Approach 2:
The patent introduces an additional process dimension by adding a second etching step after the first etching. This dimensional expansion in the process flow allows simultaneous achievement of large opening (for etching quality) and small final size (for device miniaturization).
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 ensures that the second hole is small enough to meet the size requirements for semiconductor devices while preventing etching issues due to high depth-to-width ratios, thereby improving the integration and performance of semiconductor devices.
Implementation Method 1
The protective layer is deposited on the side of the second pattern layer away from the base to be etched by using an atomic layer deposition process
Implementation Method 2
The mask layer is etched by using the first pattern layer as a mask to form a first hole and a second pattern layer
Implementation Method 3
The base to be etched is etched by using the second pattern layer and the protective layer which covers the side wall of the first hole as a mask to form a second hole
Data Source
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AI summary
The embodiments of the present application disclose a method for preparing a hole in a semiconductor device, a method for preparing a semiconductor device, and a semiconductor device. The method for preparing the hole in the semiconductor device includes: providing a base (10) to be etched and forming a mask layer (30) on the base (10) to be etched; forming a first pattern layer (40) arranged in an array on the mask layer (30); etching the mask layer (30) by using the first pattern layer (40) as a mask to form a first hole (31) and a second pattern layer (32); depositing a protective layer (50) on a side of the second pattern layer (32) away from the base (10) to be etched, the protective layer (50) simultaneously covering a side wall and a bottom portion of the first hole (31); etching the protective layer (50) which covers the bottom portion of the first hole (31); and etching a supporting layer (20) by using the second pattern layer (32) and the protective layer which covers the side wall of the first hole (31) as a mask to form a second hole (60). A critical dimension of the second hole (60) is less than a critical dimension of the first hole (31).