MatricizingVersion 3 Slide *
Transport: Indexing through tunnels
US vibration is optional
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Large Jumbo line
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Type of showers
Higher impact
2 nozzles per position
3 positions
Removed about 90 - 95 % of all particles
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Ultra Sonic equipment
Skimmer for keeping water surface clean.
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Bottom transducers 40 kHz
Side transducers 30 kHz
Removed, %
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By heat only:
3 min dwell time
Continuous improvement
Ask if there are any questions regarding mask washing / drying
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Adhesion of matrix/flowcoat layers
Formation of silanol groups
Oil, grease, particles etc.
Particles (glass) are pressed into the glass surface
Releasing materials are used to get the screen out of the mould.
Only outside screen surface is polished.
Plunger
Mould
to form silanol groups
Water rinsing / draining
Prevent acid / water intake
Like water rinsing but more effective to e.g. glass faults
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Etching with HF/HNO3
At low HF-acid concentration, mainly the F- -ion is present
adding a strong acid (HNO3);
HF F- + H+
or aged acid
stronger etching
HNO3 reduces deposition of formed Ba-silicon fluorides and removal is easier.
Typical glass layer thickness removed 3 - 4 m
Etching doubled or triplet, reduces rejects due to glass faults.
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Ask if there are any questions regarding mask washing / drying
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Purpose of precoating
Provide an intermediate layer between glass surface and flowcoat layers to assure good phosphor adhesion.
Phosphor
Glass
Precoat
Washing precoating
Flow coating
Lacquer Alu
Lacquer Alu
Flow coating
at 20 degrees Celsius
88 = degree of saponification
OH
OH
O
silanol groups on the glass surface, formed at screen washing
silanol groups adsorb PVAl
OH
OH
O-
OH
O-
OH
O
H
H
O
Equalizing
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Fixation of the precoat layer on the glass substrate by heating
Glass temp. 45 - 50 ºC
Cool down to 30 ºC
Time required is 30 to 60 min
Load to matrix line
dry PVAl ; keep screen at 30 °C
Load immediately onto matrix line.
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PVAl suppresses oxygen diffusion
Typical relation with MWW: