Miniature PCBA

The demand for digital wellness means an increasing need for small, complex electronic components. [Image courtesy of MicroCare]

Precision cleaning of electronic medical devices boosts reliability.

Jay Tourigny, MicroCare

COVID-19 has brought the importance of wearable and remote monitoring and diagnostic devices to the forefront. But these devices, with their intricate PCBAs (printed circuit board assemblies) must deliver reliable and consistent performance, particularly as they are often used in devices that are life-sustaining.

Cleaning is a key contributor to PCBA performance consistency and should be factored in when designing complex and multifaceted electronics. What cleaning processes should be adopted and how do you ensure cleanliness standards are met?

Why is reliability important?

The medical electronics market is estimated to be worth $6.3 billion in 2021 and projected to reach $8.8 billion by 2026, at a CAGR of 6.9%. The increasing adoption of IoT-based smart medical devices and the escalating demand for portable medical devices and wearable electronics are some of the prominent factors for the growth of the medical electronics market globally.

This demand for digital wellness means an increasing requirement to produce small and complex electronic components. These devices must be small, light and portable for the comfort and ease of use by the patient. Designing the highly complex miniaturized circuitry inside can be challenging for engineers since they must increase functionality, reduce the size of components and ensure they still function reliably. For example, if a PCBA inside a pacemaker were to fail, the result could be deadly. Therefore, electrical components must stand the test of time and function consistently without fail.

Cleaning is the key to reliability

Many factors should be considered when designing PCBAs. Everything from correctly positioning the components on the board, to routing the signal traces and deciding on the best flux/paste mixture. All must be planned before any prototyping or production starts. However, cleaning is a critical aspect of PCBA design that is often overlooked during initial planning and not reviewed until the final stages of manufacture.

It is usually easier to identify and resolve any cleaning problems prior to prototyping and production. This is particularly true when manufacturing high-reliability PCBAs where cleanliness is critical. Electronic medical devices must meet the validation requirements, quality standards and regulations set by governing bodies. Effective cleaning is a significant part of meeting these requirements.

The intricate circuitry used within medical devices requires careful cleaning to remove any contamination. Particulate, oils or inorganic contamination resulting from the manufacturing process should all be removed. If PCBAs are not effectively cleaned they are vulnerable to a number of problems including shorting, delamination, electrochemical migration, parasitic leakage, dendrite growth, all which could lead to PCBA failure.

MicroCare Vapor Degreaser Overview

Vapor degreasers offer a simple, repeatable process that is effective at removing contaminants [Image courtesy of MicroCare]

How to meet the cleaning challenge

Many of the difficult production and performance issues encountered by manufacturers can be reduced with the correct cleaning of the PCBAs. Vapor degreasing is one method that is meeting the cleaning challenge.

Vapor degreasers offer a simple, repeatable process that is effective at removing contaminants, whether it is general dirt and dust, or hard to remove residue left by lead-free and no-clean fluxes and solder pastes.

The advanced, non-flammable, environmentally progressive cleaning fluids used within a vapor degreasing system are inherently hostile to bioburden and can make a substantial enhancement to performance, reliability and longevity of PCBAs. They have been lab-tested and analyzed to ensure high-quality cleaning results that are reliably consistent with the added benefit of providing engineers a cleaning method with relatively simple manufacturing validations. The low viscosity and surface tension ratings of the fluid used within a vapor degreaser, combined with their volatility, allow them to clean complex parts very effectively. Crucially, vapor degreasing finishes the cleaning process by effectively drying the components. PCBAs emerge from the vapor degreaser dry and spot-free, reducing bacteria growth and bioburden risk. The outcome ensures the finished product will meet strict regulatory and validation standards required within the manufacture of electronic medical devices.

MicroCare Electronic Printed Circuit Boards with Lots of Surface Mounted Components

PCBAs emerge from the vapor degreaser dry and spot-free, reducing bacteria growth and bioburden risk. [Image courtesy of MicroCare]

Apply effective cleaning to future-proof reliability

When it comes to electronic medical devices, performance is one of the most fundamental concerns. Devices must be designed and manufactured to work consistently for the duration of their life. However, this is increasingly challenging as PCBAs become smaller and more complex.

Vapor degreasing used with specially engineered cleaning fluids is an effective solution to increasing product quality and reliability. It enables a critical cleaning process that ensures contaminated PCBAs are not the cause of device failures. It is therefore important that cleaning processes are considered during the design stage to ensure they are implemented at the beginning of manufacture to ensure reliability.

Jay Tourigny is SVP at MicroCare Medical, which offers medical device cleaning and lubricating solutions. He has been in the industry more than 30 years and holds numerous U.S. patents for cleaning-related products that are used on a daily basis in medical and precision cleaning applications. For more information, visit microcare.com.

The opinions expressed in this blog post are the author’s only and do not necessarily reflect those of MedicalDesignandOutsourcing.com or its employees.