Technical Issues - FilmStar News 2018
January 2 Collector to Targets
DESIGN...Reverse-engineering can be more reliable when P/S measurements at angles > 0 are included. New multi-angle attachments (Cary UMA, PE Lambda with ARTA/TAMS) and the Spectra Collector enable users to save data in a single file. That capability has been enhanced with DESIGN 2.61.4150 able to quickly convert multi-angle spectra to Optimization Targets. (Previously this required opening multiple spectra and tediously converting one at a time or writing a macro utilizing BASIC Function SpecTargets.)
The procedure is as follows:
Note that blue cells in the Collector grid indicate calculated data. Also note that Collector wavelength units (nm) were converted to current DESIGN units (Ám).
January 8 IndexSolve Updated with Collector
originally developed some years ago to
automate (executable video file) a user's manual procedure for deducing n,k for silver
through %R/%T measurements at multiple angles. The method is useful
for metals of known thickness when it is impossible to utilize
dispersive functions. The method depends on selecting a film
thickness wherein both %R and %T can be accurately determined.
You need to run the calculation twice, for %T and %R. The values shown below were utilized.
Upon running this you
obtain TP/TS and RP/RS 6░ columns. These were averaged (giving TR
and RR) by highlighting adjacent 6░ columns and clicking
Spectra.. Average P and S. If columns are not highlighted all
P and S columns are averaged. In practice, data are generated by
FilmStar MEASURE or by other programs via Excel transfer to
Exercise for advanced users: Add noise to calculated spectra and see how it affects results.
January 29 Spektrum Support for CEC Deposition Systems
Cutting Edge Coatings
(CEC) in Hannover, Germany manufactures deposition systems utilizing the Laser Zentrum
Hannover (LZH) Spektrum file format (.dsg).
to view or download a sample design file created in FilmStar DESIGN;
open in Notepad or (recommended)
Notepad++. Note that
some of the '##' settings refer to Spektrum software and
are not utilized by CEC.
Users unfamiliar with this advanced dialog should contact FTG Software to arrange a Glance session. At this time the Spektrum Oscillator Model is not supported. The Spektrum .dsg file includes a ##RATE entry which is specified by adding 'R=' in the Film Indices dialog Description field as shown below. User-Defined Functions are also useful for mixed material models as in 'My TiO2', a mixture of 'good' and 'bad' TiO2.
IMPORTANT: The CEC system recognizes if the expected Spektrum syntax is incorrect, for example if it cannot read material data. It cannot, however, detect erroneous values. Users must inspect layer values and verify that the final transmission spectrum matches DESIGN's. It is the user's responsibility to ensure that proper information has been uploaded to the system prior to deposition.
February 26 Peaks and Valleys in MEASURE
The ability to show peaks in FSPlot was added in 2011. In response to a user utilizing the holmium spectrum to determine wavelength accuracy in a Lambda 950, we added valleys in FSPlot Setup.. Peaks <Ctrl+K>. Note that annotations (here vertical lines displaying NIST wavelengths) must be added before plotting the spectrum. Finally, don't forget to check View.. Peaks <Ctrl+P>. As can be seen below, %T peaks are not of much use in this calibration procedure; NIST wavelengths refer to valleys.
Use the Zoom function to examine and verify results. Asymmetric extrema might be problematic.
New BASIC Sub WaveCorrect applies the Correction Function to an existing uncorrected spectrum. This should only be run ONCE!