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Oliver Werzer
Jul12-05, 11:52 PM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Hey,\n\nI have the following problem:\ni work on a powder diffractometer\nin a bragg brentano configuration.\nif i measure a theta/2theata scan\non my films i got very nice fringes.\ni can calculate the thicknesses of\neach layer with different method (by hand,\nfouriertransformation) and it is very\naccurate compared with other method like AFM.\n\nnow i want to calculate\nalso the roughness of the layers. if\ni use different software packages like\nparratt32, wingixa and so on i cannot\nachieve a good fit. therefore i want to\nknow if it is neccesary to manipulate my\ndata before? is there a need for\nlorentz-polarization correction?\nfootprint correction? other things?\n\nif someone knows a goog literature where i\ncan find some information, please tell me!\nin the publications i found there is only\na littel bit or no information about the\ncorrections! only nice fits.\n\nThanks Oliver\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">&nbsp;&nbsp;View this Usenet post in original ASCII form </a></div><P></jabberwocky>Hey,

I have the following problem:
i work on a powder diffractometer
in a bragg brentano configuration.
if i measure a \theta/2theata scan
on my films i got very nice fringes.
i can calculate the thicknesses of
each layer with different method (by hand,
fouriertransformation) and it is very
accurate compared with other method like AFM.

now i want to calculate
also the roughness of the layers. if
i use different software packages like
parratt32, wingixa and so on i cannot
achieve a good fit. therefore i want to
know if it is neccesary to manipulate my
data before? is there a need for
lorentz-polarization correction?
footprint correction? other things?

if someone knows a goog literature where i
can find some information, please tell me!
in the publications i found there is only
a littel bit or no information about the
corrections! only nice fits.

Thanks Oliver

npsmith514
Jun30-10, 08:33 AM
you probably need to do a footprint correction to normalize your data information can be found in the following places

if you have relatively good data
http://www.ncnr.nist.gov/reflpak/reflpak/html/reflred/footprint_correction.html

if you have a low SLD/critical angle you will need to calculate it manually
information can be found in case 3 of the previous link or some information is here
http://www.ncnr.nist.gov/reflpak/reflpak/html/reflred/footprint_correction.html