Aspect ratio of through hole via

I read that aspect ratio of TH plating via is between 10:1 to 6:1

I was trying to calculate the dielectric height and via pad diameter for these aspect ratios

If the via pad is 6 mil and the dielectric height is 60 mil then the aspect ratio of the via is 10:1, right ?

If the via pad is 10 mil and the dielectric height is 60 mil then the aspect ratio of the via is 6:1, right ?

It look like that manufacturing 10:1 via is more expansive and difficult then 6:1 via, is that correct ?

If yes then 4:1 via is further more easier to manufacture or have bigger via pad compared to 6:1 via. The via pad size will be then 15 mil in 4:1 via if the dielectric height is 60 mil.

The via pad has nothing to do with the aspect ratio. It’s the hole size.

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Again, that’s the hole size.

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It doesn’t work like this. 10:1 and 6:1 vias are through-holes. What impacts the cost of manufacturing is having smaller holes or blind/buried vias because they take more time to fabricate. Below 6 mils, your fab house will probably use laser drilling, which is more expensive.

This is a video of our mechanical drilling.

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Is that true 10:1 has smaller via hole compared to 6:1 ?

If yes than manufacturing 10:1 via is more expansive and difficult then 6:1 via, correct ?

Like I said, 10:1 and 6:1 are aspect ratios, not via sizes. That doesn’t impact the cost of manufacturing.

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Just for reference, this is how we laser drill.

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Thanks. I have watched the videos.

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