Vertical Dummy Contact Structure for Chip Security
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Chip cards face significant security risks due to invasive attacks, which allow counterfeiters to reverse-engineer and reproduce chips, leading to substantial losses for distributors and manufacturers.
Innovation Solution
A chip with a vertical contact structure and a vertical dummy-contact structure that includes an insulation layer, making it difficult for attackers to identify the actual connections and functionality, thereby preventing reproduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a chip uses conventional contact structures for connecting functional areas, then the chip can be easily analyzed and reproduced by attackers through invasive attacks, but implementing additional protection mechanisms increases device complexity and manufacturing difficulty
Solution Approach 1:
The patent creates dummy contact structures that are visual copies of real contact structures. These dummy structures have the same appearance, dimensions, and spatial arrangement but lack functional electrical connections. Attackers cannot distinguish between real and dummy contacts, making chip reproduction impossible. The dummy contacts are integrated into the same metal planes and transistor layers as real contacts, maintaining structural authenticity while providing security through deception.
Solution Approach 2:
The patent introduces an intermediary layer of deception between the attacker and the actual chip functionality. The dummy contact structures act as intermediaries that absorb the attacker's analytical efforts, redirecting them toward non-functional elements. This intermediary layer protects the real functional contacts by masking their true locations and connections among numerous indistinguishable dummy structures.
2Reliability
If a chip implements protection mechanisms against invasive attacks, then security is improved, but the manufacturing process and certification requirements become more stringent and costly
Solution Approach 1:
The patent merges the security protection function with the existing contact structure fabrication process. The dummy contact structures are created using the same metal deposition, etching, and patterning steps as the real contacts. They are integrated into the same transistor planes and metal layers, requiring no separate manufacturing lines or additional certification processes. The security feature becomes an inherent part of the standard chip manufacturing workflow.
Solution Approach 2:
The dummy contact structures serve multiple functions simultaneously: they act as security protection elements, fill structural gaps in the chip design, and maintain consistent manufacturing patterns across the entire chip surface. This multi-functionality allows the same manufacturing processes to produce both functional and protective elements without requiring specialized production lines or additional quality control certifications.
3Ease of manufacture
If a chip uses simple contact structures, then manufacturing is easier and less costly, but the chip becomes vulnerable to reverse engineering and reproduction
Solution Approach 1:
The patent extends the traditional two-dimensional contact layout into the vertical dimension by creating multi-layer contact structures that extend through multiple metal planes and transistor layers. The dummy contacts are positioned at various depths and orientations within the chip's three-dimensional structure, making them indistinguishable from real contacts when viewed from any single angle or plane. This dimensional complexity provides security while maintaining compatibility with standard multi-layer manufacturing processes.
Data Source
AI summary
A chip with a chip plane includes a functional area, a contact structure vertical with respect to the chip plane for connecting the functional area, which includes a conductive material, which has a predetermined length, and a vertical dummy-contact structure, which extends vertically into the functional area and which has an electrically conductive material and an insulation layer, the insulation layer being formed so that a current flow from an upper end of the dummy-contact structure to the functional area is prevented.