OSP is the new ENIG. Matte Black is the new.. Black

After a lengthy Spring Festival break, we’d like to begin fresh with something useful and something cool. This year we’ve brought in some popular PCB options that you’ve previously voiced interest in.

At long last, we welcome the ever-stylish Matte Black solder mask color and the economical OSP surface finish to our range of PCB fabrication options.

Organic Solderability Preservative (OSP)

Wait, isn’t that just copper? No. Finely sprayed on top of these pads is Organic Solderability Preservative, as the name suggests, is a water-based organic compound that is sprayed onto the surface of the pads and bonds to the copper.

PCB with “invisible” OSP surface treatment on the exposed copper pads

In deciding which surface finish to go for, you may have heard of OSP along with HASL, ENIG and others. There is a wide range of finishes used around the globe but in reality, especially at the prototyping stage, HASL, the lead-free version and ENIG are the most common.

Each has its merits and weaknesses and are suited for different applications and budgets.

In general:

  • HASL is the cheapest and enough for basic prototyping and hobbyist projects.
  • Lead-free HASL is suited for commercial boards.
  • If there are fine-pitch components or BGAs, then ENIG is preferred because of better surface planarity (flat pads).

But ENIG is expensive – that’s real gold there.

That’s where OSP comes in as a viable ENIG alternative. The OSP surface finish is so thin, that, as well being almost invisible, it hardly affects the shape of the pad, offering exceptional planarity that is comparable to ENIG. The downside is that it doesn’t keep for long and has a short shelf life, so not so good for long-term storage. It is also quite fragile and damage to the finish is not easy to spot. But if you need a quick and cheap prototype, OSP is a great option.

Summary of common PCB surface finishes offered by Seeed Fusion

Compare Seeed Fusion’s special $4.90 boards, 10 pieces, 2 layers, within 100 x 100 mm. If you want to upgrade from leaded HASL to ENIG, the price jumps to $29.90, almost 6 times as expensive. But by opting for OSP, the price is only $12.90.

OSP is now available with the standard Fusion PCB service for all materials.

The New Black

Not much in terms of performance except it’s Matte Black (enuff said). Think of the Seeed ReSpeaker, Maxustech microwave sensor and even in iPhones. Despite the additional cost, you’ve told us that it’s worth having the option available when that sleek look and extra wow factor is everything.

We’d love to be able to offer Matte Black for free, but unfortunately, it’s not feasible in the long term. The oil is more expensive and more complicated to apply. Others have famously tried and failed in the past, so we’re not going there.

Matte Black solder mask finish is now available for standard FR-4 materials at an extra $15. For that first pilot run or product release, $15 is nothing.

We are confident that these new additions will be warmly welcomed but as always, we’d love to know what you think!.

Try OSP surface finish or matte black solder mask with Seeed Fusion now.

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February 2020