Novel high-precision micropipette thermal sensor for materials thermal characterizations

A novel technique for fabricating high-resolution micropipette thermal sensors using inexpensive materials was developed. The technique can be implemented relatively easily in a laboratory setting. The micropipette sensors were constructed by filling a metal inside a glass micropipette and coating a thin film on the outer surface of a glass micropipette by PVD (Physical Vapor Deposition), so that thermocouple junctions were created at the tips of the micropipettes. The outsides of the pipettes were covered with vaporized Ni (nickel) onto a Sn (tin) based solder layer. The goal is to maintain a consistent Seebeck coefficient relationship after repeated measurements. A crystalline Si (silicon) [111] wafer was selected for testing and its thermal conductivity was found to be 155 W/m°C. This was well fitted to its known value. After confirming its reliability, FLG (a few layer graphene) was characterized for its thermal conductivity by the sensor. The thermal conductivity of the FLG was measured to 1682.52 W/ m°C.