车灯镀铝工艺

1、1Metalizing ProcessVenaria 18th-27th January 2010 Surface Treatment Training2 copyright by Automotive Lighting The metalizing process can be done with 2 technologies:Thermal evaporation Sputtering In our company we use both Introduction of Metalizing process3 copyright by Automotive Lighting Evapora

2、tion 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 vacu

3、um, 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. Thermal evaporation 4Thermal evaporation Process copyright b

4、y Automotive Lighting Diffusion pumps root pump Mechanical pump 5 copyright by Automotive Lighting Thermal evaporation processIonization Vacuum 1 E-1 mbar; 30020 mA at 1500200 VRotation 10 turn/minCarrier: air60 sAluminizing by Joule effectPre-heatingVacuum 1 E-4 mbar 2.5 0.5 V3 sEvaporationVacuum 1

5、 E-4 mbar 5.0 0.5 VRotation 12 turn/min11 sCooling Rotation 10 turn/min10 sProtection Vacuum 1 E-1 mbar35050 mA; 4000500 VCarrier: Air/hexamethildisiloxaneBetween 180-240 s (Total Cycle Time 15 min.)6 copyright by Automotive Lighting Thermal evaporation processTungsten filament Aluminum coil The des

6、ign 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.7 copyright by Automotive Lighting Thermal evaporation processBy the ways of tungsten filaments Its important to verify the good cond

7、ition of work 8 copyright by Automotive Lighting Sputtering processSputtering 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 betwee

8、n 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

9、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 targ

10、et atoms, and the surface binding energy of atoms in the target.9 copyright by Automotive Lighting Sputtering processThe 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. Its poss

11、ible to classify 2 main kind of machine:Support pieces fix10 copyright by Automotive Lighting Sputtering process2) Support pieces in moving (double rotation like themal evaporation system ) 11 copyright by Automotive Lighting Metalizing processSection of metalizing part Substrate Aluminium 100-80 nm

12、 Silicon protection 80-30 nm 12 copyright by Automotive Lighting Metalizing processSection of metalizing part 1) Adhesion test, thickness by instrument or reflectance by spectrometer Substrate Aluminium 100-80 nm Silicon protection 80-30 nm Corrosion test or thickness by elisometer Stefano CORDERO ALH I