The intrinsic registration capability of current e-beam lithographic tools has to approach or even go below the 0.10 micrometers value ( + 3(sigma) ). However, the actual level to level overlay measurements are generally found above this limit as resist materials trap the electric charges: the electron beam is deflected by the electrostatic forces, resulting in misalignment and distortion of the delineated patterns. Large pattern displacements can be observed depending on the experimental conditions. This paper aims to compare various charge reducing processes when used under exactly the same conditions (20 keV industrial machine and trilevel resist structure). No system appears as a perfect solution. There are partial solutions, but none is simple and satisfying; this contributes to the picture of electron- beam lithography as a marginal technique for IC manufacturing.

Date Published: 9 July 1992
PDF: 6 pages
Proc. SPIE 1671, Electron-Beam, X-Ray, and Ion-Beam Submicrometer Lithographies for Manufacturing II, (9 July 1992); doi: 10.1117/12.136038

Published in SPIE Proceedings Vol. 1671:
Electron-Beam, X-Ray, and Ion-Beam Submicrometer Lithographies for Manufacturing II
Martin C. Peckerar, Editor(s)