water droplet on circuit board

Today, the mobility of electronics allows us to broaden the range of when and where we use them. Consequently, electronics encounter threats such as water, extreme temperatures, shock, and contaminants. BTG Labs’ Surface Analyst™ helps electronics manufacturers build a product to stand up to elemental threats. This fast, easy, accurate, and non-destructive handheld device verifies surface cleanliness levels in order to bond, coat, and print properly on a surface.

Typical Surface Analyst Applications in Electronics Manufacturing

  • Monitor cleaning processes for solder flux
  • Verify surface readiness for conformal coating in circuit board manufacturing
  • Ensure strong bonds on solar panels
  • Guarantee bonding of print on electronics
  • Predict adhesion for UV cured adhesives
  • Measure cleanliness levels of silicon wafers used in integrated circuits
  • Ensure coatings on composite conductive equipment
  • Inspections on glass used in consumer electronic devices

Application Example

A manufacturer needed a way to ensure the protection of their circuit boards. As the core of any electronic, a circuit board must withstand stresses. However, circuit boards are highly sensitive to threats that cause damage and failure such as moisture, extreme temperature, and contaminants. To address this issue, manufacturers apply conformal coating to the circuit board for protection. By conforming to the typography of the circuit board, this coating protects the piece from these environmental threats. But, what happens when the conformal coating fails?
This manufacturer encountered challenges in creating a successful bond between the conformal coating and the circuit boards. They needed to not only ensure the coating would stick, but also, that the surface was free of contaminants before the coating was applied.

Because managing surfaces in circuit board manufacturing is doubly important, the manufacturer needed a way to ensure the surface was clean for the sake of the circuit board and for the success of the coating.

BTG Labs introduced the Surface Analyst. While measuring the surface cleanliness of circuit boards can seem almost impossible without damaging or contaminating the board, the Surface Analyst offered a way in which to do just that. The Surface Analyst deposits a microdroplet of highly purified water, thus ensuring no damage to the circuit board. The instrument instantly reveals to the user the cleanliness level of the surface.

By implementing the Surface Analyst, the manufacturer gained a way in which to verify and monitor their circuit board surfaces to guarantee successful coatings while cutting down on failure and waste.

How It Works

The Surface Analyst™ deposits a tiny liquid drop (2μl or less) onto a surface and determines the contact angle formed by the drop and the surface. This contact angle provides an immediate, quantitative measure of the state of the surface. It is sensitive to less than a single molecular layer of contamination.  The measurements are fast, taking under 2 seconds.

Unlike other contact angle measuring devices which deposit a fully-formed drop onto the surface, the Surface Analyst™ uses BTG Lab’s patented Ballistic Deposition to construct a drop on the surface from a pulsed stream of nanoliter-sized droplets. This is a mechanically robust approach that imparts kinetic energy to the growing drop, allowing it to spread to its true equilibrium shape regardless of the presence of surface roughness or imperfections. This gives a contact angle measurement that is a better indication of the true surface than angles obtained from traditional contact angle goniometers.