Thermal Profiling

We rework the most intricate devices, leading the industry in complex repairs, component salvage and protoype assembly. To tackle the kind of extremely difficult projects we receive, we develop temperature profiles that ensure our clients’ expensive — sometimes irreplacable — boards are handled with the utmost care.

Rework

Almost any cook can follow a recipe, but only a highly trained chef can take a random pile of ingredients and turn them into something that works. In the same way, assembling a board requires a precise recipe, but once the recipe has been formulated it can be applied with generally anticipated results. Complex, high-quality rework, however, requires the kind of creativity and experience found only in a master chef.

Our technicians train for a year to learn the basics of thermal profiling, and constantly update and improve their skills. It’s not simply a matter of understanding how much heat to apply and how long to apply it: an experienced eTech technician understands the art of balancing a wide range of physical limitations to arrive at the best possible result for each client and each project, carefully handling particular components while accounting for the cohesiveness of the rest of the board. The thickness of the board, the component, the size of the spheres, the pitch — all exert their influence.

Our eight VJ Electronix Rework Stations use forced nitrogen — at temperatures up to 350°C — to prevent oxidation while precisely manipulating even the most sensitive components. Nitrogen provides a number of advantages, especially for fine-pitch devices, protoypes, and complex or texpensive rework. Nitrogen’s forgiving nature makes rework less prone to defects, improving overall device quality. By incorporating nitrogen into all rework we improve solder quality, increase the wetted surface, improve the solder process and improve the appearance of the solder joint, making it easier to inspect and repair.

Inaccuracies in the thermal profile create faults in finished devices which may go unnoticed … until the device fails. Intermetallic formation must be precisely calibrated; too much can be worse than too little. Flux must be outgassed precisely to avoid void formation. Unseen or overlooked faults can create defective products, unhappy customers and public relations disasters — all for the want of an accurate thermal profile.

  • We define a number of variables to ensure the right results: the height off the heater, thermocouple location, nozzle type, device orientation on the rework station, the best way to avoid warping, and many more. Placement of the thermocouples is critical; a slight error can provide false readings that destroy the board. We do whatever we can to ensure the most precise, dependable rework possible.
  • When reworking devices, we also keep manufacturability in mind. When developing prototypes or eliminating defects, we document each step of the process to make sure that when you’re ready to go back to manufacture, you have information that will increase device life, decrease failure rates and improve profitability.

Assembly

An accurate thermal profile is also a critical component in PCB assembly. We use a Juki CUBE.460 selective soldering system to provide superior flexibility and reliability in all of our assembly operations, and employ nitrogen to ensure joint quality.

For complex or expensive devices, partial samples can be created and tested to ensure that when the first complete device is baked, components aren’t wasted on a test PCB. If needed, changes can be made to the thermal profile and additional tests run until assembly is ready to begin. Each stage of the process, from preheat to soak to reflow to cooling, is carefully monitored and each device is inspected to ensure that expectations match reality.

Quick Contact

ETECH thermal 01t

Our nine-zone Heller 1809 Mark III SMT Reflow Oven allows for even the most complex rework and assembly operations.

ETECH thermal 02t

Our eight VJ Electronix Rework Stations use forced nitrogen — at temperatures up to 350°C — to prevent oxidation while precisely manipulating even the most sensitive components.

ETECH thermal 03t

When developing prototypes or eliminating defects, we document each step of the process to make sure that when you’re ready to go back to manufacture, you have information that will increase device life, decrease failure rates and improve profitability.