车灯镀铝工艺

Protection
Vacuum 1 E-1 mbar 350±50 mA; 4000±500 V Carrier: Air/hexamethildisiloxane Between 180-240 s
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Thermal evaporation process
Metalizing Process
Venaria – 18th-27th January 2010 – Surface Treatment Training
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Introduction of Metalizing process
The metalizing process can be done with 2 technologies: 1) Thermal evaporation
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Sputtering process
Sputtering is a process whereby atoms are ejected from a solid target material due to bombardment of the target by energetic ions. It is commonly used for thin-film deposition. Physical sputtering is driven by momentum exchange between the ions and atoms in the material, due to collisions. The incident ions set off collision cascades in the target. When such cascades recoil and reach the target surface with an energy above the surface binding energy, an atom can be ejected. If the target is thin on an atomic scale the collision cascade can reach the back side of the target and atoms can escape the surface binding energy `in transmission'. The average number of atoms ejected from the target per incident ion is called the sputter yield and depends on the ion incident angle, the energy of the ion, the masses of the ion and target atoms, and the surface binding energy of atoms in the target.
Silicon protection 80-30 nm Aluminium 100-80 nm
Section of metalizing part
Corrosion test or thickness by elisometer
1) Adhesion test, thickness by instrument or reflectance by spectrometer
Aluminum coil
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Thermal evaporation process
By the ways of tungsten filaments It’s important to verify the good condition of work
Substrng
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Stefano CORDERO ALH ID Material & Process Development Automotive Lighting Holding Via Cavallo, 18 - 10078 Venaria Reale (TO) Phone +39 011 6870514 Fax +39 011 4597638 Mobile +39 331 6486164 stefano.cordero@
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Sputtering process
2) Support pieces in moving (double rotation like themal evaporation system )
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The design of pieces and the position on the jigs are important to guarantee a good evaporation , but even tungsten filament and the Al coils are fundamental for the process. Tungsten filament
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Metalizing process
Silicon protection 80-30 nm Aluminium 100-80 nm
Section of metalizing part
Substrate
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Metalizing process
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Sputtering process
The Sputtering permit an excellent control of metal thickness. Further this technique is capable of deposition of different metals that are difficult to treat by evaporation. It’s possible to classify 2 main kind of machine: 1) Support pieces fix
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Thermal evaporation Process
Mechanical pump
Diffusion pumps
root pump
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Thermal evaporation process
Ionization
Vacuum 1 E-1 mbar; 300±20 mA at 1500±200 V Rotation 10 turn/min Carrier: air 60 s
(Total Cycle Time 15 min.)
Aluminizing
by Joule effect
Pre-heating Vacuum 1 E-4 mbar 2.5 ±0.5 V 3s Evaporation Vacuum 1 E-4 mbar 5.0 ±0.5 V Rotation 12 turn/min 11 s Cooling Rotation 10 turn/min 10 s
2) Sputtering
In our company we use both
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Thermal evaporation
Evaporation is a common method of thin film deposition. The source material (small bars ) is evaporated by joule effect in a high vacuum. The high vacuum allows vapor of Al put to travel directly to substrate, where they condense back to a solid state. The metalizing phase is anticipated from a medium vacuum, where we do a plasma to eliminate humidity and particles (clean of substrate). The Al must be protected to avoid oxidation, so we do protection with silicon oils distributed in a medium vacuum which become oligomers by plasma treatment.