Flex Stiffener: Design Rules and Process Limits A flexible circuit is thin by design, and that thinness is exactly what makes it useful. The same property makes it difficult to handle, to solder and to plug into a connector, so a piece of rigid material is bonded to the flex…

Microvia Laser Drilling In HDI Boards A microvia is a small hole, typically under one hundred and fifty micrometres in diameter, that connects one layer to the next in a high density board. It is formed by a laser rather than by a drill, because a mechanical drill of that…

Production Yield Improvement in PCB Manufacturing Production yield improvement is the discipline of raising the share of boards that pass without rework, and it is the most direct lever a board shop has on both cost and delivery. The work is unglamorous: measure the real first pass yield, find where…

Squeegee Blade Wear and Solder Paste Print Quality The squeegee is the simplest part of a solder paste printer and the one that wears fastest. It is a strip of metal or polyurethane that is dragged across the stencil, and its job is to roll the paste ahead of the…

ESD Control In The Assembly Area An assembly area is a controlled environment in which every surface, every tool and every person is held at the same potential, so that a static discharge cannot pass through a component. Control is not a single product but a system of grounding, materials…

X-Ray Slice And CT Inspection For PCB Quality An X-ray slice is a cross-sectional image of a board taken from a rotational scan, and it is the only non-destructive way to look inside a plated hole, a via or a solder joint. Where a two-dimensional image collapses the whole thickness…

PCB Scrap Analysis: Tracking Real Yield Loss Scrap analysis is the work of finding out what a board shop is really throwing away, why it happens, and what the loss costs. Many shops record a scrap rate and stop there, which turns a number into a mood rather than a…

Electroless Copper Coverage and Hole Wall Control on PCBs Before a hole in a printed circuit board can be electroplated it has to be made conductive. The resin surface left by drilling is an insulator, and the thin layer of electroless copper that is deposited on it is what carries…

PCB Reflow Profile Control: From Prototype to Volume Production Buyers and engineers often focus on the finished product and forget the production line behind it. In practice, most field failures can be traced back to process decisions made during assembly. Understanding PCB reflow profile control gives you a practical advantage…

Tombstoning Causes and Prevention in Reflow Soldering Tombstoning is the defect in which a two terminal chip component stands up on one end after reflow instead of lying flat on its pads. The joint on one side forms and pulls the part upright, while the other termination is left in…