Low Resolution Rapitone Paper Bromide Photoplotting

The following information refers to emulsion coated rapitone matte paper films , imaged on our standard photoplotter upto a maximum of 400mm in size.

bromide-photoplotting

CHOOSING RESOLUTIONS

We can write masks at 4 different resolutions, called "DPI". The higher the resolution, the better the quality.

4k dpi : LOW Resolution. These papers are suitable for general low resolution printing applications, such as large checkerboard patterns. Although this resolution may resolve smaller features, we recommend keeping feature sizes above 0.5mm as corner rounding is considerable. Edge sharpness and definition is acceptable for non-critical design types, although designs with arcs/circles and lines running off 90 degree grid may show pixilation.

10k dpi : LOW Resolution. This resolution will usually resolve down to 0.2 mm lines with improved line edge qualities although still significant pixilation along edges. Corner rounding is still very noticeable. NO features such as lines / circles / spots / squares below 0.2mm unless on a 'best effort' basis previously agreed with our technicians.


FEATURE TOLERANCES

There are two different values that we specify for tolerances. The first is a ‘feature tolerance’, which equates to one specific feature (also known as CD or Critical Dimension).So, if part of your design has a 5mm square and this is a critical feature, you can use the table below to work out possible deviations to the square width, depending upon which resolution you choose. As a rule, the higher the resolution, then the more accurate the individual feature size will be.

Resolution
Material
Tolerance
4k dpi
Rapitone matte paper
+/- 50um
10k dpi
Rapitone matte paper
+/- 30um

All figures above in Microns....


DIMENSIONAL TOLERANCES

The second tolerance that customers ask us about is that of overall dimensional tolerances. These refer to the tolerances over a distance greater then 5mm – in layman’s terms, people ask us ‘how accurate will the mask be’ and these guidelines should go somewhere towards providing the tolerances in overall dimensions, depending upon the resolution chosen. Again, it goes without saying that the higher the resolution, then the more accurate the final mask.

Our paper images are produced in conditions of 21deg C / 50% humidity, and if dimensional accuracy is a concern when using the paper , then you must replicate these conditions in your own clean rooms and acclimatise the mask in these conditions for upto 8 hours before you intend to use it – only then can it be considered to be stable. We strongly recommend using glass-based substrates where dimensional stability is a concern.

NOTE:
When using films in your own production environment, be aware that ..
1 Deg C temperature change = 18 ppm (1.8um per metre length)
1% Humidity change = 9ppm (0.9um per metre)

Resolution
Microns
Low Resolutions 4k / 10k
= 50um + (Lmm * 0.5) um (maximum 200um)

NOTE: where L is measuring length in MM
All figures above in Microns....
Example, a 100mm line would have a tolerance of (50.0 +50) = +/- 100um