The design and operation of a MEMS differential scanning nanocalorimeter for high-speed heat capacity measurements of ultrathin films

A MEMS sensor has been developed for use as a calorimetric cell in an ultra-sensitive, thin-film, differential scanning calorimetric technique. The sensor contains a freestanding, thin (30 nm to 1000 nm), low-stress silicon nitride membrane with lateral dimensions of a few millimeters. This membrane, along with a thin (50 nm) metallization layer, forms a calorimetric cell with an exceptionally small addenda. This small addenda creates a very sensitive calorimetric cell, able to make heat capacity measurements of nanometer-thick metal and polymer films. The sensor fabrication and various design considerations are discussed in detail. The calorimetric technique and examples of applications are described.