Diffusion-Contact Fuse for OTP Memory Programming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing one-time programmable (OTP) memory cells require large driving elements to generate high current for programming, making it difficult to reduce element size while maintaining read stability.
Innovation Solution
A diffusion-contact fuse is used, comprising a diffusion region, a silicide layer, and a contact partially landed on both the silicide layer and isolation region, reducing programming current while maintaining high read stability through electro-migration effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If large driving elements are used to generate high current for programming, then programming capability is achieved, but element size cannot be reduced
Solution Approach 1:
The patent changes the material parameters of the fuse element by using a silicide layer instead of traditional metal interconnect, and introduces a diffusion region with specific doping concentration. These parameter changes enable the fuse to achieve programming function with lower current while reducing element size.
Solution Approach 2:
The patent employs a composite structure consisting of a diffusion region, a silicide layer, and a contact structure. This composite design combines the advantages of doped semiconductor regions (low resistance) with silicide materials (programmability), enabling both size reduction and maintained programming capability.
2Area of moving object
If element size is reduced, then integration density improves, but read stability may deteriorate
Solution Approach 1:
The patent optimizes the doping concentration parameters of the diffusion region to achieve low resistance contact, and controls the silicide layer thickness and material composition to ensure stable resistance states. These parameter optimizations maintain read stability despite the reduced element size.
Solution Approach 2:
The composite structure of diffusion region plus silicide layer provides both low resistance for small size and stable electrical characteristics for reliable reading. The diffusion region ensures good electrical contact while the silicide layer provides the programmable resistance state with high stability.
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
The diffusion-contact fuse design reduces programming current requirements while maintaining robust read stability, enabling smaller element sizes and efficient programming.
Implementation Method 1
the programming means can apply a high voltage to induce a high current (e.g., tens of milliamps) to flow through the OTP element. When a high current flows through an OTP element by turning on a program selector, the OTP element can be programmed, or burned into a high or low resistance state
Data Source
AI summary
A one-time programmable (OTP) memory cell includes a substrate comprising an active area surrounded by an isolation region, a transistor disposed on the active area, and a diffusion-contact fuse electrically coupled to the transistor. The diffusion-contact fuse includes a diffusion region in the active area, a silicide layer on the diffusion region, and a contact partially landed on the silicide layer and partially landed on the isolation region.