Evaluation of the Proximity Effect and Ghost Correction Technique for Submicron E-Beam Lithography at 50 kV and 20 kV

The magnitude of the proximity effect of 50 kV has been experimentally quantified using an electrical proximity effect tester (PET)[1,2]. The PET was delineated in MP 2400-17 resist on a trilevel stack on aluminum, using the AT&T electron beam exposure systems. At 50 kV the linewidth variation caused by the proximity effect was less than at 20 kV, but still greater than 0.25micron for a 0.5micron coded feature. The effective range of the electrons was measured to be greater than 10microns.