Miniature Forming Lens for a High-Voltage Electron-Beam Lithography System

This work presents the result of modeling a miniature forming lens for a high-voltage electron-beam lithography system. The diameter of the outer yoke is only 64 mm. This allows the installation of four electron optical systems over a six-inch photomask. For a 50-kV electron beam and 15 mm flange focal distance, the characteristics of the obtained miniature lens provide the absence of yoke saturation and a 25-nm resolution for a 100 × 100 um scanning field. A study of the dependences of the miniature lens’ electron-optical properties on the channel diameter, gap width and yoke length is performed. The obtained results enable selection of the optimal configuration of the forming lens for the development of an electron-beam-lithography system. A four-column composition will allow an increase in the efficiency of the lithography process by up to four times.