Types of Electron-Beam Lithographies

Following the invention of the SEM, it was quickly realized that the same instrument could be used to expose resists. This realization not only influenced the design of the first electron-beam tool, employing Gaussian beams in 1974, but it also influenced the design of subsequent tools employing shaped beams in 1979, the cell or character projection in 1990, and scattering contrast projection in 1996. 

Bowden, The hthographic process the physics, in Introduction to Microlithography, L.F. Thompson, C.G. Willson, and M.J. Bowden, Eds., p. 110, American Chemical Society, Washington, DC (1994). 

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