Advanced CD control technologies for EB mask writer

Abstract

With the rapid progress in the minimization in the device fabrication, it comes to be indispensable to reduce Critical Dimensional (CD) error in the mask production. The electron beam mask lithography system HL-7000M series has been developed, to meet the needs for mass production line below 90 nm node. A novel high-accuracy Proximity Effect Correction (PEC) method of exposure correction for pattern density variation is applied in this system. By using this high accuracy PEC method, CD error caused by proximity effects has been reduced to 4 nm, from 14 nm with the conventional PEC method.