We have enlisted below some of the important requirements that must be understood, making PCB medical boards distinct from ordinary PCB requirements. The impact of failure of a medical device is not equivalent to a failure of a consumer electronic product as human life may be directly affected. Thus, the below requirements are essential for the PCB medical board.
- Thermal Control. Many medical systems, such as IVD and microfluidic devices, need to have thermal management to ensure performance and safety. Vias and ground planes are integrated into the PCB stack-up to transfer and spread the heat. Metal substrates, such as aluminum, are also used to dissipate heat. A dielectric layer is still used to isolate the circuit layer and metal layer, thus good choice of a thermally conductive dielectric material should be kept in mind.
- Material Choice. Much like ordinary PCBs, PCB medical boards have a vast selection of materials that can be decided based on the intended functionality and requirements. The dielectric material used in the medical instrumentation PCB board fabrication is not limited to FR4 alone such as high glass transition temperature and flexible PCBs. As for the specific medical instrumentation PCB board fabrication, flexible PCB is the material choice for smartwatch wearable straps. Also, aluminum or other metal core PCB can be used for high thermal dissipation requirements.
- Weight and Portability. As PCB medical boards ought to be near or even in contact with patients, these devices must be lightweight and portable to ensure comfort and safety. This is the reason why most PCB medical boards also employ polymeric materials aside from known metals and FR4 substrates. Polymeric materials such as polyimide are light and can be easily bent and formed to conform to desired shapes or geometries.
- Standards and Regulations. PCB medical boards are governed by several standards and regulations, which cannot be dismissed as they are important in ensuring the reliable production of PCBs. IEC and ASTM are examples of global standards that must be complied with in aiming for medical products that are safe, reliable and of good performance and quality.
Medical PCB Board Fabrication
The shrinkage of many electronic devices has also opened possibilities of developing lightweight, and high-density medical wearables. Since medical applications take advantage of rigid-flex PCB in the aspect of flexibility, weight and portability, we will capture the fabrication process of a rigid-flex PCB medical board. This will help broaden our understanding of the difference between the production of medical PCB boards and ordinary PCB boards.
- Flex Circuit Preparation. First, a copper layer is added to the polyimide through a lamination or plating process. Drilling is then done to form holes and vias either through mechanical or laser methods. Copper used in the medical instrumentation PCB board fabrication is plated on the drilled holes to establish the conductive paths.
The copper circuit pattern is revealed through the application of a photosensitive resist mask and the subsequent etching process. Both sides of the flexible circuit board are applied with cover-lays to also act as solder masks during the component placement process. After these processes, the flex is individually cut through a punching or blanking knife.
- Lamination. The flex circuit is then laminated to the rigid sections, including the other flexible sections depending on the product design. Each flexible section usually is limited to 2 conductive layers for certain designs to maintain flexibility. Some stiffeners are also incorporated into the fabricated rigid-flex boards to provide more mechanical support.
BGA PCB Board for Medical Equipment
To achieve a higher number of Input/Output (I/O) in a tiny wearable device, a BGA PCB board for medical equipment is frequently used. A BGA PCB board is a high-density packaging technology that is assembled using surface mount technology in which grid balls at the bottom of the package IC are soldered to the printed circuit boards.
The solder pads of a BGA PCB board for medical equipment have a surface finish typically using ENIG, which is short for electroless Nickel Immersion Gold. The vias and surface pads have a flat Nickel layer applied using electroless plating. Afterwards, a thin gold layer is plated to avoid Nickel oxidation and further enhance solderability. ENIG technology for medical controllers provides excellent
The criticality of medical applications necessitates a thorough medical PCB manufacturer selection assessment.
Important Applications of Medical PCB
Printed Circuit Boards have several direct applications in the medical sector. PCB medical boards have improved efficiency and accuracy in medical procedures and tracking geared toward patient treatment and care. Medical PCB manufacturers are also following suit to provide you with PCBS that meet these applications. Learn more about these applications in the following section.
- Medical Wearables. Collection of vital signs and health data can be easily performed using medical wearables. Wearables have simplified healthcare technology with easy tracking outcomes through non-invasive techniques. These devices are equipped with sensors that are attached to the body to provide insights into the actual condition of the body. Some examples of medical wearable devices include health and fitness trackers, and remote monitoring devices.
- In Vitro Diagnostic Instruments. IVD instruments are devices that are utilized outside the body to gather important information about body fluids, tissues and cells to diagnose a disease. The hardware that is used for in vitro diagnostic instruments employs specialized PCB medical boards. The goal of IVD instrumentation is to improve the accuracy of analysis, speed up diagnosis through automation and integration and reduce the overall cost.
- Wireless Medical Sensors. Wireless medical sensors encompass sizable areas of healthcare technology. Temperature, force and moisture are just a few of the many physical attributes that can be collected by wireless medical sensors. These sensors consist of PCB medical boards that exhibit good conductivity, compatibility flexibility and high accuracy.
- Fluid Control Systems. Valves and pumps at the micro-scale are prominent instruments in biomedical applications. PCB medical boards serve as a base for lab-on-chip devices on which these microvalves and pumps are integrated to enable control of fluids. Another fluid manipulation method using PCB is through electrodes, achieved through photolithography and etching processes.
