Electron beam lithography (EBL) is the practice of scanning a focused electron beam to draw custom shapes on a electron sensitive film (eFilm). The electrons change the solubility of the film enabling the selective removal of the exposed or unexposed regions by immersing the eFilm in a solvent. EBL can draw custom patterns with a resolution down to 50 [nm] easily and can achieve 10 [nm] and below with great skill and effort. EBL is used in research for prototyping and in semiconductor factories for making masks.
An electron beam lithography tool generates a beam of electron using the same technology as scanning electron microscopes (SEM). A major component in an EBL system that distinguishes it from an SEM is a high precision stage. The stage is microscopically flat along both axes of motion and it is equipped with a laser interferometer system that tracks the position, X and Y, of the stage with an accuracy of 0.6 [nanometers]. More advanced EBL systems are also equipped with a laser interferometer system for keeping the sample leveled. An entry level EBL system costs approximately $1,000,000 and more expensive systems are engineered to write faster and over larger areas.