Gate And Active Contact Protrusions for Scaled MOSFET Interconnects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The scaling down of metal-oxide-semiconductor field-effect transistors (MOS-FETs) in semiconductor devices leads to deterioration in operational properties, necessitating improved electric characteristics to maintain performance.
Innovation Solution
The semiconductor device incorporates a gate electrode with an electrode protruding portion and an active contact with a contact protruding portion, both featuring stepwise structures, which are formed to facilitate connections with lower interconnection lines without additional vias or contacts, thereby enhancing integration density and preventing misalignment issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If MOS-FETs are scaled down to meet increasing demand for small pattern size, then device density and integration are improved, but operational properties and electric characteristics deteriorate
Solution Approach 1:
The gate electrode is extended in the vertical dimension to form a protruding portion that reaches down to the lower interconnection line. This vertical extension allows the gate electrode to maintain effective electrical control over the channel while accommodating the scaled-down horizontal dimensions, thereby preserving operational properties despite pattern size reduction
Solution Approach 2:
The gate electrode protruding portion is formed in advance to directly contact the lower interconnection line before final interconnection layer deposition. This preliminary structural arrangement ensures proper electrical connection and signal control is established early in the fabrication process, preventing operational deficiencies that would result from inadequate gate control in scaled devices
2Reliability
If additional vias or contacts are added to improve connections with lower interconnection lines, then electrical connection reliability is improved, but device complexity and manufacturing steps increase
Solution Approach 1:
The gate electrode structure is merged with the interconnection structure by having the gate electrode protrude and directly contact the lower interconnection line. This consolidation eliminates the need for separate via or contact structures, reducing overall device complexity while ensuring reliable electrical connection between the gate and lower interconnection layers
Solution Approach 2:
The gate electrode serves dual functions: it provides the essential gate control function for transistor operation and simultaneously acts as an interconnection element that directly contacts the lower interconnection line. This multi-functionality eliminates the need for additional dedicated connection structures, simplifying the overall device architecture
3Ease of manufacture
If conventional flat gate electrode and contact structures are used, then manufacturing is simpler, but misalignment issues and process failures increase
Solution Approach 1:
The gate electrode structure features localized protrusion at specific positions where contact with lower interconnection lines is required. This local structural modification provides enhanced alignment tolerance and contact assurance at critical interfaces without complicating the overall fabrication process, thereby improving process reliability while maintaining manufacturing simplicity
Solution Approach 2:
The protruding portion of the gate electrode is designed with extended dimensions that provide a larger contact area and tolerance margin with the lower interconnection line. This beforehand structural cushioning compensates for potential alignment variations during fabrication, preventing process failures before they occur
Data Source
AI summary
A semiconductor device may include an active pattern on a substrate, a source/drain pattern on the active pattern, a channel pattern connected to the source/drain pattern, a gate electrode on the channel pattern, an active contact on the source/drain pattern, a first lower interconnection line on the gate electrode, and a second lower interconnection line on the active contact and at the same level as the first lower interconnection line. The gate electrode may include an electrode body portion and an electrode protruding portion, wherein the electrode protruding portion protrudes from a top surface of the electrode body portion and is in contact with the first lower interconnection line thereon. The active contact may include a contact body portion and a contact protruding portion, wherein the contact protruding portion protrudes from a top surface of the contact body portion and is in contact with the second lower interconnection line thereon.