Ocean Optics ElliCalc - Manual (Page 48)

Ocean Optics Germany GmbH Thin Film Metrology
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settings of the menu EditStructureSetup and may be set to:
-- well defined values like: lower limit=200 nm and upper limit=800 nm
(with any thickness value between 200 and 800 nm)
-- constant range like lower limit=thickness-100 nm and upper limit=thickness+100 nm
Thus the search region is restricted to a rather wide, but more or less "reasonable" range. Of course
you may also set the limits very narrow, even to a search range of zero.
9. An option „user limits“
If you press this option you may set the lower and upper limit to any value between 0 and 300000
nanometers. These values are equivalent to having absolutely NO KNOWLEDGE of any thickness.
10. A submenu “layers” with lots of commands to delete, insert or switch layers. Especially important is the
possibility to include “thick layers” = include the calculation of backside reflections.
9.1.2 Catalogues
In the menu EditStructure you find a row “catalogues” for each layer. You may choose the TYPE of material
like: glasses, semiconductors, metals etc. In the next row “materials” you may choose the actual material of
your layer.
There are different catalogues for photoresists (for different companies like Shipley, MRT and others).
You may add a new catalogue manually or use the menu Edit Refraction Index.
9.1.3 Materials
In the menu EditStructure you find a row “materials” for each layer. You may choose the material itself: Si,
GaAs, Ge etc.
In the previous row “catalogues” you first have to choose the TYPE of material of your layer (like
“semiconductors”). There are different catalogues for photoresists (for different companies like Shipley,
MRT and others).
You may add a new material manually or use the menu Edit Refraction Index.
9.1.4 Thickness
ElliCalc uses values for the thickness between 0 and 300000 nm (=300 micrometers).
9.1.5 Estimates
ElliCalc uses a maximum value for the estimates of 300000 nm (=300 micrometers).
In automatic mode it is NOT necessary to add values for the upper and lower estimate.
You should give reasonable values for these limits in fitting mode as this influences the time for calculation
considerably.