A mask electron-beam writer for production lines beyond 100 nm was developed. The system HL-7000M is equipped with cell projection function for high critical dimension accuracy. The newly developed technologies are a cell projection optics, objective lens optics, a low distortion stage, a highly accurate control electronics, and high accuracy proximity effect correction hardware. This article describes the details of the electron optics and its performances. (C) 2003 American Vacuum Society. [DOI: 10.1116/1.15477251].