Printed Circuit Board Sensor Technology: Rigid vs. Flexible vs. Additive Manufacturing

Abstract

There is no denying that printed circuit boards (PCB) have integrated themselves into all sorts of technology that we have today. They are in the computers on which we work, the appliances we use, and the sensors that monitor our world; but how did the PCB come into existence? The history of the PCB is fascinating, and it reaches further back in time than one might think. Its design and manufacturing processes were influenced by many inventors such as Thomas Edison and Paul Eisler, and the PCB continues to evolve today. Traditional substrates for rigid and flexible PCBs are still viable, but as technology advances, the materials that compose PCBs are changing as well. In addition, long-established manufacturing methods are beginning to make way for additive manufacturing processes (AM). These new AM processes are not quite ready to manufacture at full capacity, but they can certainly speed up the development process of a single device. All of this traditional and emerging technology is especially applicable to PCB sensors. PCB sensors provide a unique avenue for exploring the world. Using PCB manufacturing allows for versatility in design. The many designs allow for the creation of conductive, capacitive, or inductive measurements. However, it is important to bear in mind the particle being measured and to optimize the sensor design to be able to maintain as much contact with the measurand as possible. PCB manufacturing also creates the opportunity to test multiple designs to determine which is the best for the application. This thesis presents an in-depth look at the PCB’s history, materials, manufacturing processes, optimization, and how these specifically apply to multiple PCB sensor designs.