Multi-Charged Particle Beam Writing Stage Speed Control

The patent implements variable stage speed control where the stage speed is dynamically adjusted based on the pattern density of different regions. In regions with low pattern density, the stage speed is reduced to minimize latency and improve throughput, while in regions with high pattern density, the stage speed is increased to maintain constant dose and prevent overexposure. This dynamic adjustment resolves the contradiction between maintaining simple constant speed control and achieving high throughput with accurate dose control.

The patent applies local quality by implementing region-specific writing parameters. The writing region is divided into multiple regions with different pattern densities, and each region is assigned optimized irradiation times and stage speeds. In regions with low pattern density where proximity effect correction is needed, longer irradiation times are applied locally, while in regions with high pattern density, shorter irradiation times are used. This localized optimization achieves accurate dose control without uniformly increasing the writing time across the entire wafer, thus maintaining high throughput.

The patent dynamically adjusts stage speed based on real-time pattern density information rather than using a fixed speed determined by the maximum irradiation time. The control system calculates the appropriate stage speed for each region based on its specific pattern density and required irradiation time, allowing the stage to move faster in high-density regions (reducing latency) while maintaining accurate dose control through coordinated beam intensity and timing adjustments.