公开(公告)号：US10553394B2

公开(公告)日：2020-02-04

申请号：US14915288

申请日：2014-08-28

Applicant: ASELTA NANOGRAPHICS

Inventor： Nader Jedidi ,  Patrick Schiavone ,  Jean-Hervé Tortai ,  Thiago Figueiro

IPC: H01J37/304 ,  H01J37/285 ,  H01J37/317

Abstract: A method for projecting an electron beam onto a target includes correction of the scattering effects of the electrons in the target. This correction is made possible by a calculation step of a point spread function having a radial variation according to a piecewise polynomial function.

公开(公告)号：US09934336B2

公开(公告)日：2018-04-03

申请号：US13861284

申请日：2013-04-11

Applicant: ASELTA NANOGRAPHICS

Inventor： Jean-Herve Tortai ,  Patrick Schiavone ,  Thiago Figueiro ,  Nader Jedidi

IPC: G06F17/10 ,  G06F17/50 ,  H01J37/22 ,  H01J37/317 ,  G03F7/20 ,  B82Y10/00 ,  B82Y40/00

CPC classification number: G06F17/5009 ,  B82Y10/00 ,  B82Y40/00 ,  G03F7/2059 ,  H01J37/222 ,  H01J37/3174 ,  H01J2237/226 ,  H01J2237/31769

Abstract: A method for projecting an electron beam used notably in lithography by direct or indirect writing as well as in electron microscopy, is provided. Notably for critical dimensions or resolutions of less than 50 nm, the proximity effects created by the forward and backward scattering of the electrons of the beam in interaction with the target must be corrected. This is traditionally done using the convolution of a point spread function with the geometry of the target. In the prior art, said point spread function uses Gaussian distribution laws. At least one of the components of the point spread function is a linear combination of Voigt functions and/or of functions approximating Voigt functions, such as the Pearson VII functions. In certain embodiments, some of the functions are centered on the backward scattering peaks of the radiation.