Primary Electron Beam Trajectory Evaluation for Accurate Multi-Beam Inspection

The patent applies preliminary action by evaluating the trajectory of the primary electron beam before actual sample inspection. The system acquires images of the primary electron beam using photoelectric converters and calculates trajectory deviations in advance, allowing for pre-correction of beam positioning errors. This ensures that when multiple primary electrons irradiate the sample, their trajectories are already optimized to prevent image overlap or omission, thereby maintaining both high throughput and accurate irradiation positioning.

The patent introduces an intermediary evaluation system that acts as a mediator between the primary electron beam generation and the sample inspection processes. This intermediary system uses photoelectric converters to capture beam images, calculates trajectory deviations, and provides correction data without interfering with the main inspection workflow. The evaluation device serves as a bridge that enables accurate trajectory assessment while maintaining relative system simplicity through modular integration.

The patent replaces the mechanical/photochemical system of photosensitive film with an electronic detection system using photoelectric converters. Instead of using film that requires physical exposure, development, and analysis, the system employs electronic sensors that directly convert electron beam positions into digital signals for immediate processing. This substitution dramatically reduces evaluation time while maintaining or improving trajectory measurement precision through faster data acquisition and digital image processing capabilities.