Why does a QFN need more paste control than a QFP?

Because the joint is under the body. Paste volume, stencil aperture and the thermal pad design determine whether voids stay acceptable, and none of it can be inspected visually; the process must be right by design.

Does a smaller package always save space?

Not on its own. Fine-pitch packages need escape routing, more layers or via-in-pad, and inspection coverage. The space saved by the package can be lost to the routing it demands.

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Component Packaging Technology

The package decides how a part is placed, soldered, cooled and inspected. Choosing it early avoids a layout that cannot be built.

Hitech Circuits Engineering Desk

Shenzhen, China · PCB fabrication and assembly

2 min read

Published: 2016-10-27

Last updated: 2026-10-18

Technical review: Process figures checked against our published capability sheet. View capability sheet

Chip and moulded packages

Two-terminal passives and small discretes: simple to place, easy to inspect, and where most of the placement volume sits.

Leaded packages

SOIC, TSSOP and QFP expose the solder fillet, so AOI can verify the joint. Pitch drives stencil design rather than inspection strategy.

Area-array packages

QFN, BGA and LGA hide the joint. Thermal pads, void limits and X-ray coverage become part of the specification.

Module and press-fit

Modules shift assembly to a connector or a press-fit interface; press-fit needs controlled hole tolerance and insertion force, which is a fabrication and assembly decision together. Whichever family the BOM uses, it is settled at the pcb assembly services review, where the stencil, the X-ray coverage and the insertion force are specified.

Technical Specifications

Supported packages: 01005 to BGA, QFN, QFP, SOIC, press-fit
Inspection: AOI, X-ray, microscope
Acceptance: IPC-A-610 workmanship

Frequently Asked Questions

Why does a QFN need more paste control than a QFP?
Because the joint is under the body. Paste volume, stencil aperture and the thermal pad design determine whether voids stay acceptable, and none of it can be inspected visually; the process must be right by design.
Does a smaller package always save space?
Not on its own. Fine-pitch packages need escape routing, more layers or via-in-pad, and inspection coverage. The space saved by the package can be lost to the routing it demands.