tThis paper presents a comprehensive procedure for the design and implementation of thin film heatersmanufactured on glass substrates. The thermal and electrical behavior of the heaters have first been simu-lated and proper design solutions have been adopted for increasing the thermal resistance of the heaters,thus decreasing their power consumption. Trenches were adopted in order to thermally isolate the heaterfrom the glass substrate. The presence of four different layouts of trenches on the back and the front sideof the glass slide with different geometries was extensively simulated. The simulated geometries weremanufactured and an automatic sawing machine was exploited to dig 240 m wide trenches in the glasssubstrate. The trenches were typically stopped at about 80 m from the opposite surface. Techniquescommonly adopted for measuring the temperature coefficient of resistance, the thermal resistance andthermal capacitance in the case of Si-based microheaters have conveniently been modified to take intoaccount the fundamentally different thermal parameters of a heater manufactured on glass. An experi-mental improvement of the thermal resistance up to 217% on a heat sink and 30% in air has been obtainedwhen a large part of the thermal mass under the microheater was removed. The thermal capacitance wasalso considerably decreased, thus improving the dynamic thermal behavior.
Design and experimental characterization of thin film heaters on glass substrate for Lab-on-Chip applications
SCORZONI, Andrea;PLACIDI, Pisana;TAVERNELLI, MICHELE;
2015
Abstract
tThis paper presents a comprehensive procedure for the design and implementation of thin film heatersmanufactured on glass substrates. The thermal and electrical behavior of the heaters have first been simu-lated and proper design solutions have been adopted for increasing the thermal resistance of the heaters,thus decreasing their power consumption. Trenches were adopted in order to thermally isolate the heaterfrom the glass substrate. The presence of four different layouts of trenches on the back and the front sideof the glass slide with different geometries was extensively simulated. The simulated geometries weremanufactured and an automatic sawing machine was exploited to dig 240 m wide trenches in the glasssubstrate. The trenches were typically stopped at about 80 m from the opposite surface. Techniquescommonly adopted for measuring the temperature coefficient of resistance, the thermal resistance andthermal capacitance in the case of Si-based microheaters have conveniently been modified to take intoaccount the fundamentally different thermal parameters of a heater manufactured on glass. An experi-mental improvement of the thermal resistance up to 217% on a heat sink and 30% in air has been obtainedwhen a large part of the thermal mass under the microheater was removed. The thermal capacitance wasalso considerably decreased, thus improving the dynamic thermal behavior.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
