Semiconductor Spacer Formation via Etchable Core Masking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor device manufacturing, the formation of spacers with offset distances between them leads to etching offsets and loss of etching stopping layers due to inconsistent opening depths during over etching.
Innovation Solution
A method involving forming an etchable material layer on a substrate, patterning to create openings, depositing a core material, etching to expose the layer, depositing spacers, and controlled over etching to ensure consistent substrate etching depth, using techniques like plasma etching and ALD for spacer deposition, and back etching to maintain core and spacer integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If spacers are formed using conventional patterning, then the manufacturing process can be completed, but the openings between spacers have offset distances causing etching inconsistency
Solution Approach 1:
The patent applies preliminary action by forming a sacrificial etchable material layer before spacer deposition. This layer is patterned to define core positions, and spacers are deposited relative to these predefined positions. The etchable material layer serves as a reference that ensures consistent opening depths are established before the actual spacer formation, preventing offset distances that would compromise etching stopping layer integrity.
2Ease of operation
If over etching is performed to expose cores, then the spacers can be fully formed, but etching offsets occur due to inconsistent opening depths
Solution Approach 1:
The patent uses the etchable material layer as an intermediary that mediates between the spacer formation and the substrate etching. This intermediate layer is removed after spacer formation to expose the cores, allowing controlled over etching without compromising the underlying substrate. The intermediary layer acts as a protective buffer that enables complete spacer exposure while maintaining precise etching depth control through the previously established opening geometry.
3Ease of manufacture
If conventional spacer formation is used, then the process is simple, but the openings have offset distances causing process failures
Solution Approach 1:
The patent applies self-service by using the etchable material layer to automatically define the positions and depths of openings that will become spacer locations. The layer is patterned to create openings at precise positions, and when the spacers are deposited and subsequently processed, the openings self-align to the correct positions and depths without requiring additional alignment steps. This self-aligning mechanism maintains manufacturing precision while keeping the overall process relatively simple.
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 method ensures consistent over etching of the substrate, preventing etching offsets and maintaining the integrity of etching stopping layers by controlling the depth of openings between spacers, thereby addressing the issue of distance offset.
Implementation Method 1
the back etching is implemented by using a plasma etching method
Implementation Method 2
the oxide is deposited by using a flowable chemical vapor deposition (FCVD) method
Implementation Method 3
the spacers are an oxide; and the oxide is deposited by using an atomic layer deposition (ALD) method
Data Source
AI summary
The present application relates to the field of semiconductor technologies, and discloses methods for manufacturing a semiconductor device. The manufacturing method includes: forming an etchable material layer on a substrate; forming multiple openings on the etchable material layer by means of patterning processing to determine a position of a core; etching the substrate at bottoms of the multiple openings, so that the bottoms of the multiple openings extend into the substrate; depositing a material of the core to fill the multiple openings; etching the material of the core so as to expose the etchable material layer; removing the etchable material layer to leave multiple cores; depositing spacers; over etching the spacers so as to expose the multiple cores, and etching a part of the substrate, where an etching depth of the substrate is the same as a depth to which the openings extend into the substrate; and removing the multiple cores. The methods address the problem of a distance offset of gaps between spacers.