Nanowire Capacitor Plugs for Semiconductor Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The scaling down of semiconductor devices poses challenges in achieving improved performance, quality, and yield due to issues such as misalignment and defect formation during the fabrication process.
Innovation Solution
The semiconductor device incorporates nanowire plugs with a conductive liner and conductor, along with a unique capacitor contact design featuring a neck and head portion, and a coverage layer to reduce misalignment and defect formation, utilizing spacers and specific materials like metal silicide and polysilicon to enhance the fabrication process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If conventional fabrication processes are used for scaling down semiconductor devices, then device dimensions are reduced, but misalignment and defect formation increase
Solution Approach 1:
The patent applies preliminary action by forming spacers and coverage layers before final patterning steps. The spacers are formed on sidewalls of contact holes to define precise locations for subsequent features, while coverage layers are deposited beforehand to protect underlying structures and prevent defects during processing. This preliminary structuring enables accurate alignment even as device dimensions scale down.
Solution Approach 2:
The patent uses spacers as intermediary structures that mediate between contact holes and subsequent features. These spacers serve as intermediate elements that transfer positional information and enable precise alignment of capacitor contacts and other features relative to the contact holes, reducing misalignment issues during scaling.
2Productivity
If device scaling continues to improve computing ability, then device density increases, but fabrication quality and yield deteriorate
Solution Approach 1:
The patent segments the fabrication process into distinct stages with intermediate structures. Contact holes are formed first, then spacers are added to segment and define subsequent feature locations. Coverage layers are deposited to segment and protect different regions. This segmentation allows each stage to be optimized independently, maintaining quality while achieving higher density.
Solution Approach 2:
The patent applies beforehand cushioning by depositing coverage layers that protect underlying structures from damage and contamination during subsequent processing steps. These coverage layers act as a cushion or protective barrier that prevents defect formation, thereby maintaining fabrication quality and yield as device density increases.
3Area of stationary object
If capacitor contact dimensions are reduced to increase device density, then area occupied by contacts decreases, but alignment precision with underlying structures worsens
Solution Approach 1:
The patent transitions from two-dimensional contact hole patterning to three-dimensional spacer formation. By forming spacers on the sidewalls of contact holes, the invention adds a vertical dimension for alignment definition. This allows precise lateral positioning of capacitor contacts relative to contact holes even when contact dimensions are reduced, as the spacer height provides a robust alignment reference independent of contact width.
Data Source
AI summary
The present application discloses a semiconductor device with nanowire plugs and a method for fabricating the semiconductor device. The semiconductor device includes a substrate having first regions and second regions; a plurality of capacitor contacts positioned over the second regions, at least one of the capacitor contacts having a neck portion and a head portion over the neck portion, wherein an upper width of the head portion is larger than an upper width of the neck portion; a plurality of bit line contacts positioned over the first regions and a plurality of bit lines positioned over the bit line contacts; a plurality of capacitor plugs disposed over the capacitor contacts, wherein at least one of the plurality of capacitor plugs includes a plurality of nanowires, a conductive liner disposed over the nanowires, and a conductor disposed over the conductive liner; and a plurality of capacitor structures disposed respectively over the capacitor plugs.