Smart Subfield Method For E-Beam Lithographny

摘要

The present disclosure provides a method of improving a layer to layer overlay error by an electron beam lithography system. The method includes generating a smart boundary of two subfields at the first pattern layer and obeying the smart boundary at all consecutive pattern layers. The same subfield is exposed by the same electron beam writer at all pattern layers. The overlay error caused by the different electron beam at different layer is improved.