Metal Gate Electrical Fuse Integration in High-K Process
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional poly-silicon e-fuses face challenges in scaling down due to particle pollution and voltage control issues, limiting component density and applicability in nano-scaled integrated circuits.
Innovation Solution
A method integrating an electrical fuse and metal gate transistor process using a high dielectric constant (high-k) material and metal gate (HK/MG) process, involving the formation of dummy gate stacks, source/drain regions, and metal conductive structures to create a smaller and more stable e-fuse structure, allowing for increased component density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If poly-silicon e-fuse is used in conventional memory structure, then the e-fuse can be fabricated in the top metal layer, but particle pollution during burning causes damage to adjacent components and requires large pitches, decreasing component density
Solution Approach 1:
The patent changes the material parameter from poly-silicon to metal (such as tungsten), which fundamentally alters the burning mechanism. Metal e-fuses do not produce particle pollution during burning like poly-silicon does, eliminating the need for large pitch spacing while maintaining reliable e-fuse functionality. This material parameter change directly resolves the contradiction between reliability and component density.
2Reliability
If poly-silicon e-fuse is used, then the e-fuse can be programmed with high voltage, but the voltage provided in scaled-down integrated circuits gets smaller, making control harder and limiting applicability
Solution Approach 1:
The patent changes the material parameter from poly-silicon to metal, which fundamentally alters the electrical properties. Metal e-fuses have different resistance characteristics and can be programmed with lower voltages compared to poly-silicon e-fuses. This makes them compatible with scaled-down integrated circuits where supply voltages are reduced, thereby improving adaptability while maintaining programming capability.
3Reliability
If large pitches are used between poly-silicon e-fuse structure and adjacent components to reduce particle pollution damage, then component damage is reduced, but component density decreases
Solution Approach 1:
The patent changes the material parameter from poly-silicon to metal, which eliminates the particle pollution problem during e-fuse burning. Since metal does not produce particles when burned like poly-silicon does, the need for large pitch spacing to protect adjacent components is eliminated. This allows components to be placed closer together, increasing component density while maintaining protection of adjacent components.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach minimizes component size and ensures stable operations, effectively integrating the e-fuse process into the 32/28 nanometers process, enhancing component density and overcoming the limitations of poly-silicon e-fuses.
Implementation Method 1
a metal conductive structure is formed to fill the openings and form a metal gate transistor and an electrical fuse
Data Source
AI summary
The present invention provides a method of integrating an electrical fuse process into a high-k/metal gate process. The method simultaneously forms a dummy gate stack of a transistor and a dummy gate stack of an e-fuse; and simultaneously removes the polysilicon of the dummy gate stack in the transistor region and the polysilicon of the dummy gate stack in the e-fuse region. Thereafter, the work function metal layer disposed in the opening of the e-fuse region is removed; and the opening in the transistor region and the opening in the e-fuse region with metal conductive structures are filled to form an e-fuse and a metal gate of a transistor.