As the CD specification on Masks is getting more tighten, the fogging effect by re-scattered incident electron at a high acceleration c-beam system and the loading effect at dry etching step due to pattern density are current critical issues for mask making. These give rise to the variation ofmean CD value and the degradation of global CD uniformity. So we have to correct these effects accurately in order to meet the CD specification for design rule 0. 1 5um or below devices.In this paper, we have applied a new positive CA (chemically amplified) resist from Fuji Film Arch co., It was written at 50 kV variable vector scan B-beam system and we tried to classify the CD error by the fogging and loading effect, respectively. Also we have compared with ZEP7000 resist, non-CAR positive type, which is used widely for conventional c-beam mask making to assess the CAR performance, especially in terms of CD error causing by the fogging effect. Through this comparison test, we found that the CD error due to the fogging effect shows somewhat different value according to resist type and writing strategy even though use same exposure dose. In this paper, we have assumed that such results are due to the difference of dose latitude. Dose latitude is different as intrinsic contrast (y) value of each resist and writing strategy such as writing pass, should affect on beam profile (dose profile), it can also change pattern profile of resist and it can fmally cause a dose latitude difference.Finally, we have evaluated for CD mean error and uniformity error by fogging and etch loading as open ratio (40%, 60%, 80%) changing, respectively.

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