Low frequency induction heating for the sealing of plastic microfluidic systems

Microfluidic systems are being used in many applications and the demand for such systems has been phenomenal in past decades. To meet such high volume market needs, a cheap and rapid method for sealing these microfluidic platforms which is viable for mass manufacture is highly desirable. Low frequency induction heating has been introduced as potential basis of a cost-effective, rapid production method for polymer microfluidic device sealing in preceding publications. Through this technique excellent bond strength was achieved, withstanding an air-pressure of up to 590 kPa. However, it has been found that during the bonding process it is important to effectively manage the heat dissipation to prevent distortion of the microfluidic platform. The heat affected zone, and the localised melted area, must be controlled to avoid blockage of the microfluidic channels or altering the channels’ wall characteristics. This work presents an analytical approach to address the issues and provide a basis for process optimisation and design rules.