Evaluating Desorption Baking Cycles for Moisture Sensitive Integrated Circuits
Baking moisture sensitive ICs requires matching package thickness and carrier heat ratings to balance desorption speed against intermetallic lead oxidation risks.
Surface Mount Assembly Yield
Process Efficiency
A statistical manufacturing ratio represents the percentage of printed circuit boards completed without defects during the automated placement and reflow of surface-mount components. Achieving a high surface mount assembly yield requires precise control over paste printing, component placement and reflow temperature profiles. This percentage functions as the primary measure of the productivity and profitability of an electronics assembly line.
High yields ensure that the cost per unit remains within the budget and that production schedules are met without requiring extensive rework.
Defect Classification
Defects that reduce the output quality include solder bridging, misaligned components and solder voids. High-speed optical inspection systems scan the boards after reflow to identify and classify these anomalies automatically. Identifying the root causes of recurring defects allows process engineers to adjust machine parameters and prevent future failures.
In-Line Optimization
Monitoring paste deposition thickness and placement accuracy before the boards enter the reflow oven prevents many defects from occurring. If a solder deposit is outside the specified limits, the board is cleaned and reprinted rather than being sent through the oven. This proactive step saves expensive components and reduces the rework required on the finished assemblies.
Yield Calculation
The final calculation is based on the number of defect-free boards divided by the total number of boards started in the production run. This measurement provides a clear view of process capability and assists in scheduling future production runs.