Optimal electrode design for microminiature electronic optics

Objectives. The work set out to systematically analyze and optimize the overall design and technological characteristics of microminiature electron-optical systems for achieving maximum performance indicators. The study paid special attention to establishing relationships between the geometric parameters of the system and its functional characteristics.

Methods. The research is based on comprehensive mathematical modeling of electron dynamics in a complex five-electrode scheme that accurately reproduces the actual design of a compact electron-beam microcolumn. This approach was used to establish the quantitative dependencies of resolution and electron beam intensity critical system performance indicators on fundamental geometric parameters: interelectrode distances, diaphragm aperture configurations, and output angular size. The main efforts focused on determining the optimal parameter values while ensuring minimal focal spot size and simultaneously maximizing beam energy.

Results. The computer modeling revealed the determining influence of each component of the five-element electron-optical structure on the formation of qualitative electron flow characteristics. A pronounced minimum in electron beam diameter was established at a specific combination of geometric and electrical system parameters. The thus-obtained optimum was used to develop a new methodology for designing and calibrating compact electron-beam devices that ensures maximum resolution and high sensitivity with minimal power consumption. Detailed analysis demonstrated that the optimal electrode configuration reduces spherical aberration by 25% compared to traditional solutions.

Conclusions. The developed design approach for microcolumn electron-optical systems significantly enhances performance while expanding the functional capabilities of electron microscopes and related analytical instruments. The practical significance of the work is confirmed by the possibility of creating devices with record resolution indicators in compact sizes. An important achievement is the establishment of quantitative optimization criteria for enabling targeted improvement of electron-beam system characteristics.

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