Microsystem Technologies

, Volume 20, Issue 10–11, pp 1881–1889 | Cite as

A Monte Carlo study of the primary absorbed energy redistribution in X-ray lithography

  • P. Meyer
  • F. J. Pantenburg
Technical Paper


The minimum feature size producible by LIGA X-ray lithography is fundamentally limited by the redistribution of primary doses via photoelectrons and the influence of the resulting dose distribution on resist development. Secondary radiation from mask and substrate are well known as source for pattern distortion in deep X-ray lithography. Numerical simulations by means of Monte Carlo simulations using PENELOPE (Salvat et al. in PENELOPE-2008: a code system for Monte Carlo simulation of electron and photon transport., 2008) are applied to quantify these additional dose values in the resist/substrate interface and the irradiated/shadowed interface. A significant reduction of the additional dose by secondary radiation from the plating base is not observed for Au and Ti layers thicker than 10 nm. The influence of polarized or unpolarized X-rays might be neglected for structure dimensions larger than a few 10 nm. As an example of critical dimension, simulations were used to predict the structure quality of grating structures with a period of 2.4 μm and duty cycle 0.5 in a resist layer of 300 μm.


PMMA Dose Distribution Primary Dose Secondary Radiation Dose Deposition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. Depaola GO, Longo F (2006) Measuring polarization in the X-ray range: new simulation method for gaseous detectors. Nucl Instrum Methods Phys Res Sect A 566:590–597. doi: 10.1016/j.bbr.2011.03.03 CrossRefGoogle Scholar
  2. Depaola GO, Leguizamon GN (2009) Measuring polarization in the X-ray range: simulation for the impact gas mixture and pressure in gaseous detectors. X-Ray Spectrom 38:519–525. doi: 10.1002/xrs.1209 CrossRefGoogle Scholar
  3. Griffiths SK (2004) Fundamental limitations of X-ray lithography: sidewall offset, slope and minimum feature size. J Micromech Microeng 14:999–1011CrossRefGoogle Scholar
  4. Meyer P (2012) Fast and accurate X-ray lithography simulation enabled by using Monte Carlo method. New version of DoseSim: a software dedicated to deep X-ray lithography (LIGA). Microsyst Technol 18(12):1971–1980CrossRefGoogle Scholar
  5. Meyer P, Schulz J, Hahn L (2003) DoseSim: Microsoft-Windows graphical user interface for using synchrotron X-ray exposure and subsequent development in the LIGA process. Rev Sci Instrum 74(2):1113–1119CrossRefGoogle Scholar
  6. Mohr J, Grund T, Kunka D, Kenntner J, Leuthold J, Meiser J, Schulz J, Walter M (2012) High aspect ratio gratings for X-ray phase contrast imaging. AIP Conf Proc 1466:41–50CrossRefGoogle Scholar
  7. Pantenburg FJ (2007) Instrumentation for microfabrication with deep X-ray lithography. AIP Conf Proc 879:1456. doi: 10.1063/1.2436339 CrossRefGoogle Scholar
  8. Salvat F, Fernandez-Varea JM, Sempau J (2008) PENELOPE-2008: a code system for Monte Carlo simulation of electron and photon transport.

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Institute of Microstructure Technology (IMT)Karlsruhe Institute of TechnologyEggenstein-LeopoldshafenGermany

Personalised recommendations