Semiconductor Memory Bit Line Arrangement for Parasitic Capacitance Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Highly integrated semiconductor memory devices face challenges with increased parasitic capacitor capacitance due to closer bit line spacing, leading to decreased operation speed and the generation of voids in contact plugs, which affect device quality.
Innovation Solution
The semiconductor memory device design features side surfaces of neighboring bit lines that do not face each other, with contact plugs and conductive pads arranged to reduce parasitic capacitor capacitance and prevent void formation by increasing the distance between bit lines and optimizing the contact plug structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If bit lines are spaced closer to achieve high integration, then device integration density is improved, but parasitic capacitor capacitance increases and operation speed decreases
Solution Approach 1:
The patent introduces a stepped structure where bit lines are positioned at different heights (first bit line at first height, second bit line at second height). This vertical dimension separation reduces the parasitic capacitance between adjacent bit lines while maintaining high integration density, thereby improving operation speed without sacrificing integration.
2Quantity of substance
If bit lines are spaced closer to achieve high integration, then device integration density is improved, but voids are generated in contact plugs
Solution Approach 1:
The stepped structure positions bit lines at different heights, which redistributes the stress and mechanical loads on contact plugs. This reduces the formation of voids in contact plugs during the manufacturing process, improving contact plug quality and device reliability while maintaining high integration density.
3Quantity of substance
If distance between bit lines is reduced to increase integration, then integration density is improved, but parasitic capacitor capacitance increases in inverse proportion
Solution Approach 1:
By separating bit lines vertically into different height levels, the patent effectively increases the distance between adjacent bit lines in the vertical dimension. This reduces the parasitic capacitor capacitance formed between neighboring bit lines, addressing the harmful effect of high capacitance while maintaining high integration density through compact horizontal spacing.
Data Source
AI summary
A method of manufacturing a semiconductor device includes providing a substrate having junction regions and contact plugs formed thereon. A second insulating layer is formed over a first insulating layer and includes first and second pad holes extending in different directions and exposing the contact plugs. First and second conductive pads are formed in the first and second pad holes, respectively. A third insulating layer is formed and includes dual damascene patterns and pad contact holes. The dual damascene pattern exposes the first conductive pad, and each pad contact hole exposes a second conductive pad. First pad contact plugs and a first bit line are formed in the dual damascene pattern and a second pad contact plug is formed in each pad contact hole. A fourth insulating layer including trenches is formed. Each trench exposes a second pad contact plug. A second bit line is formed in each trench.