Photographs of corrosion and surface defects

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Photographs of flaws in the Allflex films were taken when the boards arrived in September '08 and again in March '09 after being stored in a dry Nitrogen environment. The first two photographs below show that there was already evidence for corrosion or poor quality of the copper surface on one of the 5 micron boards when they arrived from the manufacturer, but it is not clear that this problem became worse over time.

figure 1a: Photograph of 5micron/Left#2 flaw taken 09/08.
figure 1b: Photograph of 5micron/Left#2 flaw taken 03/09.

There are marks on one of the 5 micron center boards that from a distance look like fingerprints but actually turn out to be scuff/scratch marks:

figure 2a: Photograph of 5micron/Center#2 flaws taken 09/08.
figure 2b: Photograph of 5micron/Center#2 flaws taken 03/09.

Here are some other examples of flaws found on the 5 micron boards:

figure 2c: Photograph of 5micron/Left#2 flaws taken 03/09.
figure 2d: Photograph of 5micron/Center#2 flaws taken 03/09.



There is evidence for degradation of 2 traces on the same 5 micron center board that I was not able to verify already existed when the board came from the manufacturer:

figure 3: Photograph of 5micron/Center#2 bad traces taken 03/09.


Below are before and after photographs for one of the central 2 micron boards. There is evidence for either oxidation of the copper or left-over photo-resist material present upon arrival of the boards from the manufacturer. Again, it does not appear that these flaws got worse over time.

figure 4a: Photograph of 2micron/Center#2 flaws taken 09/08.
figure 4b: Photograph of 2micron/Center#2 flaws taken 03/09.
figure 5a: Photograph of 2micron/Center#2 flaws taken 09/08.
figure 5b: Photograph of 2micron/Center#2 flaws taken 03/09.

Almost all of the 2 micron boards have regular marks indicating possible left-over contamination from rollers:

figure 6a: Photograph of roller marks on 2 micron board.
figure 6b: Photograph of roller marks on 2 micron board

Here are some more examples of localized surface defects on the 2 micron boards:

figure 7a: Photograph of surface defect on 2 micron center#1 board.
figure 7b: Photograph of surface defect (oxidation?) on 2 micron center#2 board