Integration technique of Pt/PtRh high- temperature thin film thermocouple sensors fabricated via magnetron sputtering

Abstract

The high-temperature thermocouple sensors were fabricated via magnetron sputtering， and the thermocouple patterns were prepared by using mask deposition， the sensing materials of thermocouples were Pt and PtRh， and the insulating layers were Al2O3 and SiO2. The results show that insulating layers Al2O3/SiO2 are able to ensure the electrical insulation and stability of the sensors at 1200 ℃. The precision of Pt/PtRh thermocouples reaches 200 μm， and the thermocouples can work under 1200 ℃ for 2200 min. After a 4000 min-cycling tests， the output voltage deviation is less than 1%. The thickness of whole thermocouple sensor is less than 20 μm， and can be integrated between the alloy and the thermal barrier to measure the temperature of the alloy surface. The multilayered structure exhibits stable signal output without delamination and separation during the service test.

Keywords

• high-temperature thin film thermocouple
• pt/ptrh thermocouple
• seebeck effect
• aluminum oxide insulating layer
• silica insulating layer