First Article Inspection is the first quality gate on the SMT assembly line and the most effective defense against batch-level failures. Why does the industry say "FAI can stop 80% of batch failures"? Because once the first article passes, every subsequent board repeats the same standardized process; if the first article is not properly verified, what awaits you is mass rework or even scrapping. Entire batches of ICs mounted in the wrong orientation, a whole reel of wrong capacitors, BGA components placed the wrong way... most of these batch failures, each costing hundreds of thousands in losses, can be caught in advance by one solid first article inspection. Industry data shows that over **80% of batch-level quality failures in SMT production can be intercepted through first article inspection**.

So what exactly should a complete first article inspection check? The checklist below covers every key item from component placement to hidden BGA solder joints — worth bookmarking for every procurement and process manager.

I. Component Placement Inspection

Reference designator vs. BOM ： Verify one by one that the reference designators on the first-article PCBA match the BOM completely, confirming no missing, extra, or wrong components — the first line of defense against "wrong part" failures

Placement position & offset ： Check whether components are offset, and whether the offset exceeds 25% of the pad area; excess offset directly affects soldering reliability and electrical connections

Polarity orientation ： Confirm the diode cathode direction, IC pin-1 direction, and tantalum capacitor positive/negative orientation are correct — reversed polarity is one of the most typical batch failures in SMT

Placement flatness ： Confirm components sit flat on the pads with no tombstoning, standing up, or flipping

Juehui Weiye practice: We run **AOI automatic inspection + dual manual verification** during first article inspection to ensure placement position and polarity orientation are flawless.

II. Solder Joint Quality Inspection

- Joint fullness & wetting: Check that solder joints are full and well-wetted, with no cold joints, insufficient wetting, or insufficient solder.

- Solder bridge check: Check for solder bridges between adjacent pads, especially between fine-pitch IC pins — a high-risk zone for shorts.

- Solder ball residue: Check for solder balls around the pads to prevent particles from causing shorts or reliability issues.

Juehui Weiye practice: We use 3D AOI + AI dual detection with a defect detection accuracy of 99.98%.

III. Hidden BGA/QFN Solder Joint Inspection

BGA solder joints are hidden beneath the chip and cannot be inspected by eye — X-Ray inspection is required:

1. Solder ball bridging: Check whether solder balls are bridged (shorted).

2. Void rate: Check whether the void rate exceeds the limit. Industry standard: consumer electronics single-ball void rate **≤25%**; automotive electronics / medical devices **≤15%**.

3. Offset: Check whether solder ball offset is within the standard range.

Juehui Weiye practice: Equipped with X-Ray equipment supporting 30°/45° tilted scanning, with 100% inspection of BGA solder joints.

IV. Dual Independent Verification of Polarity Components

During first article inspection, polarity components undergo "dual independent verification" — after one operator completes the check, a second operator independently re-verifies it, avoiding missed detection caused by fatigue from long single-person operation. This is the most effective — and most underestimated — measure against polarity batch failures. Juehui Weiye insists that two operators independently verify polarity components during first article inspection.

V. What Should a Proper First Article Report Include?

A complete first article report is not only the basis for production line release, but also an important record for downstream quality traceability. At minimum it should include:

- Inspection date/time

- Equipment ID

- Operator information

- Judgment results of each inspection item

- Defect images and coordinate positions

- X-Ray inspection images (if BGA is present)

- Confirmation signatures

Closing

First article inspection takes the time of "one batch" to save the rework of "an entire batch." If your project has special first article requirements — such as specifying a void rate limit, requiring X-Ray images to be retained, or requesting dual-review signatures — we recommend noting "First Article Inspection Requirement" when placing your order, and Juehui Weiye engineers will provide you with a dedicated first article inspection plan.