Microscale surface thermometry using SU8/Rhodamine-B thin layer

In the present paper, we propose a microscale surface thermometry using SU8/Rhodamine-B thin layer (SRTL). The ultra-thin SRTL is coated on the microheater which serves as a heat source for microscale heating. Surface-temperature distribution of the SRTL is measured with high spatial and temperature resolutions in a temperature range between 30 and 80 °C. Propagation of isotherms on the SRTL is visualized with a temperature resolution on the order of 0.1 °C. Spatial error in the measurement was analyzed, which depends on the size of interrogation window. The present concept of SU8 thin film in combination with Rhodamine-B signifies a considerable improvement in the indirect measurement method of surface temperature inside polymer-based microfluidic channels.