1. EJA January 2002 1 abab Dust Level Control in Phototooling Basics Eric JanssensJanuary 2002

2. EJA January 2002 2 abab What is dust ? Any material particles that may have a negative effect on their environment

3. EJA January 2002 3 abab Sources of dust Natural dust Cosmic dust from outer space Eruption of volcano’s Sand, stone... due to erosion by wind and water Seeds, pollen Humans Man generated dust Exhaust by industry and traffic Generated by any friction Human body tissue: hair, skin particle, sweat, ….

4. EJA January 2002 4 abab Dust generated by the human body Calling generates 20,000 particles Coughing generates 600,000 particles Sneezing generates 1,200,000 particles A man looses 1 hair every 15 minutes A man looses 15 grams of skin tissue every day

5. EJA January 2002 5 abab Dust generated by peoples action Writing on paper30µm particles Folding paper60µm particles Rubbing on a painted surface90µm particles Rubbing metal on metal100µm particles Putting on a screw100µm particles ….. By moving man make dust particles air born

6. EJA January 2002 6 abab Dust particles - Size distribution Air born dust particles range in size from 0 to +/- 50  m There are many small particles and fewer larger ones Remark: dust particles may conglomerate

7. EJA January 2002 7 abab Dust particles - Size distribution

8. EJA January 2002 8 abab Definition Clean Room Class Clean room class x means: one cubic feet of air contains x particles of 0,5  m or smaller

9. EJA January 2002 9 abab

10. EJA January 2002 10 abab The importance of clean room conditions As long as dust particles are relative small compared to the lines and spaces they don’t cause much trouble Stricter demands for PCB fabrication Ever decreasing line and space widths Stricter tolerances for lines and spaces and pads More layers Higher yield Today the size of an average dust particles is ¼ to ½ of an average L/S Today dust particles cause more defects and the defects are more expensive

11. EJA January 2002 11 abab Dust particles in PCB production Dust particles jeopardise image formation: Phototool generation Dust on the film while plotting Dust in the light path while plotting Dust on the plotter drum (fly off, out focus) Dust on the film while processing Primary imaging Secondary imaging Dust particles scratch phototools and resist

12. EJA January 2002 12 abab Dust measurement Measuring/counting tools Particle sizeMeasuring device 2 - 100 µm Filter > 20 µm Petri dish

13. EJA January 2002 13 abab Petri dish

14. EJA January 2002 14 abab Pert dish

15. EJA January 2002 15 abab Pert dish

16. EJA January 2002 16 abab Dust measurement Measuring/counting tools Particle sizeMeasuring device 2 - 100 µm Filter > 20 µm Petri dish 0.5 - 30 µm Particle counters with light* 0.1 - 5 µm Particle counter with laser light* * does not measure the heavier dust particles Remark The naked human eye can see: 50 µm particles under normal conditions 25 µm particles under ideal conditions

17. EJA January 2002 17 abab Dust measurement: take care We are fighting an invisible enemy

18. EJA January 2002 18 abab PCB production anno 2000 To remain competitive in the PCB industry production is to be done in clean room conditions where the dust level is well controlled

19. EJA January 2002 19 abab Clean room: the compromise A clean room has to be build correctly and used correctly Find a compromise Quality of the installationversusinstallation cost Discipline appliedversuscomfort

20. EJA January 2002 20 abab Clean room: how to organise No paper or card board (paper is compressed dust) Limit access of people Limit access of materials Avoid transportation from one compartment to another (install hatch) No cutting or punching of film in the clean room No knifes,no scissors, nail files, no pencils No posters, no photos, no radio Use clean room certified tools and equipment discipline discipline discipline discipline discipline discipline discipline

21. EJA January 2002 21 abab Clean room: how to act No paper or card board (paper is compressed dust) Clean feet Dress correctly (overall, hair cap, over shoes, gloves) Never ever enter in “out side” clothing, not even for just a second Never ever leave the clean room in clean room clothing No brief cases, no handbags No food, no drinks, no smoking Move slowly and as little as possible Keep films in vertical position, use (humidity tide) envelopes Clean the film as often as needed discipline discipline discipline discipline discipline discipline discipline

22. EJA January 2002 22 abab Clean room: maintain dust level Golden rule Prevent dust generation (people, production process, environment) Prevent dust from entering the clean room Remove dust

23. EJA January 2002 23 abab Clean room: maintain dust level Implement cleaning programme per batch, shift, day, week, month what to clean, how to clean Remark: after cleaning the dust level is higher as before vacuum cleaner out of the clean room Replace mats Replace filters Wash clean room clothing in special washing machine discipline discipline discipline discipline discipline discipline discipline

24. EJA January 2002 24 abab Clean room: SPC programme Dust level at all relevant locations Cleaning Pressure over the filters Air flows.… discipline discipline discipline discipline discipline discipline discipline

25. EJA January 2002 25 abab The ideal phototool lab Shoeshine Hatch Film stock Changing room Overalls Haircap Glovers Over shoes Check Retouch Label Measure Copy onto diazo Laminate Climitise film + +++ ++++ +++ Chemistry supply   Plotter +++++ Dust retaining mat Hatch Lock Package ++   Processor

26. EJA January 2002 26 abab Dust level control at Agfa Agfa’s commitment Production in class 1,000 Cutting and packaging in class 5,000 Special PCB packaging Film safe

27. EJA January 2002 27 abab Dust level control at Agfa

28. EJA January 2002 28 abab Dust level control at Agfa

29. EJA January 2002 29 abab Dust level control at Agfa

30. EJA January 2002 30 abab Dust level control at Agfa

31. EJA January 2002 31 abab Dust level control at Agfa

32. EJA January 2002 32 abab PCB packaging

33. EJA January 2002 33 abab Film safe 790 mm x 680 mm: FROJN 1179 mm x 870 mm: FROFG 1690 mm x 1480 mm: FPMM3

34. EJA January 2002 34 abab Conclusion Working in clean room conditions is producing with well-focused discipline in a well-monitored environment in order to control defects

35. EJA January 2002 35 abab Conclusion Dust level control in the PCB industry is a question of common sense and discipline! but it makes the difference between making or loosing money