概要（Overview）

Hitachi developed the electron beam mask writer HL-7000M for 90nm node reticle production. New technologies, such as a novel electron beam optical column, a 1-nm address grid and improved proximity effect correction are used in the system. It has two electrostatic deflectors, a 50-kV electron gun and a maximum beam size of 2 µm ×2 µm. It can emit up to a current density of 20 A/cm2. The writing strategy uses a variable shaped beam, vector scanning and continuous stage moving exposure. To comply with high volume data, it can accept a hierarchy data format which can effectively be compressed into a small file. The new storage area network (SAN) we adopted achieves high-speed data transfer and does not need a high-volume disc system.