摘要 |
Charged-particle-beam (CPB) optical systems are provided that reduce the required number of power supplies used to energize the constituent lenses and deflectors, while imparting no adverse effects on stability and settling time of the power supplies. Such CPB optical systems project and form an image of an irradiated portion of a mask, wherein the image passes through a mask that receives the charged-particle-beam illumination and is projected onto a wafer by a two-stage lens and multiple deflectors. At least most of the deflectors used for aberration reduction comprise, respectively, a main coil having a large ampere-turn and an auxiliary coil having a small ampere-turn. The main coils of the such deflectors are driven by the same power supply.
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