Advantages and Disadvantages of Printed Sensors

This page explores the advantages and disadvantages of flexible printed sensors, highlighting the benefits and drawbacks of this technology.

Introduction

Traditional PCB-based electronic devices are known for being rigid and bulky. They also tend to be heavier and have a fixed form factor. Flexible printed sensors and flexible PCBs have emerged as solutions to these limitations. Several industry trends are driving their adoption, including the Industrial Internet of Things (IIoT), advancements in healthcare, and the rise of smart homes and smart cities.

Printed sensors find applications in a variety of areas, such as:

• Temperature and humidity monitoring
• Air quality measurement
• Leak detection
• Fingerprint sensing
• Force sensing
• Vibration identification
• Flexible displays
• Solar products
• Batteries

Basics and Types of Printed Sensors

Using 3D printing techniques, various types of sensors are manufactured based on input, output, and other mechanical properties. These printed sensors leverage flexible hybrid electronics, combining printing and silicon technologies.

Here’s a breakdown of different types of flexible printed sensors:

• Printed Pressure Sensor: These sensors operate on piezoresistive or piezoelectric principles. Common applications include force-sensitive touchpads and smart flooring.
• Printed Temperature Sensor: Utilizing flexible printing technology, these sensors are manufactured in 2D for cost-effectiveness. They are used in mobile phones, laptops, electric vehicles, and other applications.
• Printed Light Sensor (or Optical Sensor): These sensors use the organic photovoltaic principle along with optimized light detection.
• Printed Capacitive Strain Sensor: These are often used in e-textile applications, like medical rehabilitation monitoring and AR (Augmented Reality) gloves.
• Printed Gas Sensor: Used for measuring indoor and outdoor air quality, these sensors are compact and consume less power.
• Printed Biometric Sensor: Based on electro-chemical principles, these sensors measure electrical impulses in the human body, such as brain activity, heart rate, respiration rate, and muscle activity.
• Matrix Sensor: Primarily used in capacitive sensing applications, matrix sensors measure changes in electric current supplied to columns or rows, rather than voltages.

Advantages of Printed Sensors

Here are some of the key benefits of using printed sensors:

• Thin and Flexible: They are remarkably thin and flexible, enabling integration into unconventional spaces.
• Cost-Effective Production: Large-scale manufacturing leads to cost-effective production.
• Customization: Flexible shapes and printing methodologies allow for customized printing to suit different applications. They are excellent for rapid prototyping.
• Smaller Size Integration: Printed sensors contribute to creating smaller flexible products. Their small size facilitates easy integration with other components.
• Faster Response: They respond more quickly to stimuli compared to traditional sensors.

Disadvantages of Printed Sensors

Despite their advantages, printed sensors also have some drawbacks:

• Lower Performance: They typically offer lower performance compared to conventional sensors.
• Shorter Life Cycle: Their lifespan is generally shorter than that of conventional sensors.
• Advanced Manufacturing Required: Production requires the latest manufacturing technologies.
• Difficult Handling of Thinned Dies: Thinned dies are difficult to manage and attach to printed traces.