The main advantages of direct e-beam writing:

High Resolution
E-Beam lithography reaches a resolution level unequalled by any other method. Lateral dimensions down to 10nm can be obtained.

Pattern Fidelity
Due to its intrinsically high resolution, excellent pattern definition can be achieved with appropriate exposure schemes.

 

Overlay to Existing Technology Levels
E-Beam patterns can be overlayed to existing features with very high accuracy. Registration signals from reference markers are used for this purpose.

Fast Prototyping without Need for Mask Production
E-Beam direct write is a computer-controlled sequential process.
No pattern masters are required, making it the ideal tool for flexible generation of low volume prototypes.