Self-Aligned Contact and Line Structures for Dense DRAM Layouts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for reducing feature spacing in microelectronic devices, such as DRAM cells, face challenges in alignment precision, leading to undesirable shorts and capacitive coupling effects, which complicates the manufacturing process and increases errors.
Innovation Solution
The method involves forming self-aligned contact structures by creating sacrificial line structures and trenches over interlayer dielectric material, with plug structures extending through the dielectric material and into semiconductive structures, allowing for precise alignment and reduced manufacturing complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional methods are used to reduce feature spacing in microelectronic devices, then feature density increases, but alignment precision deteriorates leading to shorts and capacitive coupling effects
Solution Approach 1:
The patent introduces a self-aligned contact structure that acts as an intermediary element between digit lines and other features. This contact structure includes a contact opening formed through the interlayer dielectric material that is automatically positioned by the deposition process itself, rather than requiring separate alignment steps. The contact structure serves as a mediator that enables reduced spacing while maintaining precision through its self-positioning capability.
Solution Approach 2:
The contact structure is designed to be self-aligned through the deposition process. The contact opening is formed by depositing conductive material that automatically conforms to the underlying topography and positions itself correctly relative to the digit lines and other features. This self-service mechanism eliminates the need for complex external alignment methodologies and reduces manufacturing complexity while maintaining high alignment precision.
2Area of stationary object
If feature spacing is reduced to increase integration density, then device compactness improves, but manufacturing complexity increases due to complex alignment methodologies
Solution Approach 1:
The contact structure utilizes self-alignment through the deposition process itself. The conductive material is deposited in a manner that automatically positions the contact opening correctly without requiring complex external alignment steps. This self-service approach simplifies the manufacturing process while enabling reduced device area for high integration density.
Solution Approach 2:
The patent merges the contact formation process with the existing deposition工艺流程. The contact opening is formed as an integral part of the conductive material deposition process, combining multiple functions into a single step. This merging reduces the number of separate manufacturing steps and lowers overall process complexity while achieving compact device design.
3Manufacturing precision
If conventional alignment methodologies are used, then feature spacing can be reduced, but manufacturing time increases due to complex and time-consuming processes
Solution Approach 1:
The contact structure achieves automatic positioning through the deposition process itself. The conductive material self-organizes to form the contact opening at the correct location without requiring time-consuming external alignment steps. This self-service mechanism maintains precise feature spacing control while significantly reducing manufacturing cycle time.
Solution Approach 2:
The patent skips the complex external alignment steps that are traditionally required for precise feature spacing. By using self-aligned contact structures, the process rushes through to the final configuration more quickly, eliminating intermediate alignment steps that would extend manufacturing time while maintaining precision.
Data Source
AI summary
A method of forming a microelectronic device comprises forming interlayer dielectric material over a base structure comprising semiconductive structures separated from one another by insulative structures. Sacrificial line structures separated from one another by trenches are formed over the interlayer dielectric material. The sacrificial line structures horizontally overlap some of the semiconductive structures, and the trenches horizontally overlap some other of the semiconductive structures. Plug structures are formed within horizontal areas of the trenches and extend through the interlayer dielectric material and into the some other of the semiconductive structures. The sacrificial line structures are replaced with additional trenches. Conductive contact structures are formed within horizontal areas of the additional trenches and extend through the interlayer dielectric material and into the some of the semiconductive structures. Conductive line structures are formed within the additional trenches and in contact with the conductive contact structures.