Memory Device Multilayer Insulating Structure Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The miniaturization of memory devices poses challenges in improving yield and critical dimensions due to difficulties in aligning contact elements and forming capacitor structures, leading to operational errors and reduced product yield.
Innovation Solution
A memory device with a multilayer insulating structure and self-aligned contact plugs is developed, featuring a second contact element with a wider top surface and narrower bottom surface, and a fourth insulating layer with a tapering cross-sectional profile to enhance alignment and protect the second insulating layer, improving yield and critical dimensions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If memory devices are miniaturized to meet consumer demand for smaller portable electronics, then the volume and weight of memory devices are reduced, but the yield and manufacturing precision deteriorate due to difficulties in aligning contact elements and forming capacitor structures
Solution Approach 1:
The patent applies preliminary action by forming the first insulating layer and second insulating layer with different widths before forming the contact elements. The first insulating layer has a wider width than the second insulating layer, which pre-establishes the alignment relationship between contact elements and capacitor structures, ensuring that contact elements are automatically aligned with the underlying capacitor structures during the formation process, thereby improving manufacturing precision in miniaturized devices
Solution Approach 2:
The patent applies local quality by creating different insulating layer configurations at different locations. The first insulating layer extends wider than the second insulating layer, providing different structural characteristics in different regions: the wider first insulating layer provides alignment guidance while the narrower second insulating layer provides electrical isolation, thus improving both alignment precision and device performance in miniaturized structures
2Manufacturing precision
If contact elements are aligned with capacitor structures in miniaturized devices, then manufacturing precision is improved, but the device complexity increases due to the need for multilayer insulating structures with different widths
Solution Approach 1:
The patent applies universality by designing the first insulating layer to serve multiple functions simultaneously: it provides electrical isolation between different structures, provides alignment guidance for contact elements, and maintains structural integrity. This multi-functional design achieves precise alignment without requiring additional dedicated alignment structures, thereby reducing device complexity while improving manufacturing precision
Solution Approach 2:
The patent applies merging by combining the alignment function and insulation function into a single first insulating layer structure. Instead of using separate alignment marks and separate insulation layers, the first insulating layer is designed with a wider width that inherently provides both the alignment reference and the electrical insulation, thus reducing structural complexity while achieving precise alignment
3Ease of manufacture
If conventional manufacturing methods are used for miniaturized memory devices, then production costs are maintained, but product yield decreases due to operational errors from misalignment
Solution Approach 1:
The patent applies self-service by designing a structure where the first insulating layer automatically guides the alignment of contact elements without requiring additional external alignment processes or tools. The wider first insulating layer self-provides the alignment reference, enabling the manufacturing process to self-correct and self-align, thereby improving product yield without increasing manufacturing complexity or cost
Data Source
AI summary
A memory device and a method for manufacturing the memory device are provided. The memory device includes two first gate structures and a multilayer insulating structure. The multilayer insulating structure includes a first insulating layer, a second insulating layer, a third insulating layer, and a fourth insulating layer sequentially from bottom to top. The width of the second insulating layer is equal to that of the third insulating layer, and smaller than that of the first insulating layer. The width of the bottom surface of the fourth insulating layer is greater than the width of the top surface of the third insulating layer. The memory device includes a capacitor contact plug formed between the first gate structures. The capacitor contact plug includes a first contact element, a buffering layer, and a second contact element. The second contact element has a top surface wider than its bottom surface.