Non-Aligned Gate Structure for PUF Threshold Voltage Variation

The patent applies asymmetry by intentionally designing semiconductor regions with non-aligned widthwise ends, creating asymmetric transistor structures where the source and drain regions have different effective widths. This asymmetric configuration increases threshold voltage variation among transistors in the PUF array, enhancing the uniqueness and reliability of the PUF response while maintaining manufacturability through standard lithographic processes.

The patent applies local quality by introducing non-alignment only at specific locations (widthwise ends) of the semiconductor regions while maintaining alignment at other critical interfaces. This localized asymmetry achieves the desired threshold voltage variation without requiring complex manufacturing processes, as the non-aligned regions can be formed using standard lithographic patterning and selective etching techniques.

The patent introduces asymmetry in the form of non-aligned widthwise ends of adjacent semiconductor regions, creating local variations in transistor geometry. This asymmetric design can be implemented using conventional fabrication processes by adjusting lithographic patterns or etching parameters for specific regions, thereby maintaining ease of manufacture while significantly enhancing PUF response uniqueness through increased threshold voltage variation.