Micro thermoelectric device(μ-TED)emerges with great attention in energy generation,thermal management,and heat sensing applications.However,the large sensitive area is necessary to accommodate enough thermoelectric ...Micro thermoelectric device(μ-TED)emerges with great attention in energy generation,thermal management,and heat sensing applications.However,the large sensitive area is necessary to accommodate enough thermoelectric couples(TCs)for a high thermoelectric performance.This limits the potential in micro energy harvesting and ultrasensitive sensing applications.Here,we adopted an optimized MEMS-based process to fabricate the ultra-sensitive micro-thermoelectric device(μ-TED).With the help of MEMS-compatible electrochemical deposition,the small size(25μm),high aspect ratio(1:1.25),and alternating distributed P/N structures are achieved.As a result,theμ-TED realizes an ultra-high integration density of 19,900 thermoelectric couples per cm2.Moreover,it shows a great thermoelectric sensitivity of 212 mV/(K·cm2)and a competitive power factor of 0.51μW/(K2·cm2),which means theμ-TED is competent for miniaturized applications.Additionally,theμ-TED shows an ultra-low detection limit of 5 mm/s and a short response time of 100 ms,revealing great potential in fast detections of the ultra-low airflow.Furthermore,the ultra-sensitiveμ-TED is utilized as a flexible breath sensor,due to its compact size.The breath signal of different motion states is successfully detected.These results confirm that the ultra-sensitiveμ-TED holds outstanding potential for ultra-sensitive airflow sensing and energy harvesting devices.展开更多
基金supported by the Project(NO.62502010320)the National Key Research and Development Program of China(2020YFB2009102).
文摘Micro thermoelectric device(μ-TED)emerges with great attention in energy generation,thermal management,and heat sensing applications.However,the large sensitive area is necessary to accommodate enough thermoelectric couples(TCs)for a high thermoelectric performance.This limits the potential in micro energy harvesting and ultrasensitive sensing applications.Here,we adopted an optimized MEMS-based process to fabricate the ultra-sensitive micro-thermoelectric device(μ-TED).With the help of MEMS-compatible electrochemical deposition,the small size(25μm),high aspect ratio(1:1.25),and alternating distributed P/N structures are achieved.As a result,theμ-TED realizes an ultra-high integration density of 19,900 thermoelectric couples per cm2.Moreover,it shows a great thermoelectric sensitivity of 212 mV/(K·cm2)and a competitive power factor of 0.51μW/(K2·cm2),which means theμ-TED is competent for miniaturized applications.Additionally,theμ-TED shows an ultra-low detection limit of 5 mm/s and a short response time of 100 ms,revealing great potential in fast detections of the ultra-low airflow.Furthermore,the ultra-sensitiveμ-TED is utilized as a flexible breath sensor,due to its compact size.The breath signal of different motion states is successfully detected.These results confirm that the ultra-sensitiveμ-TED holds outstanding potential for ultra-sensitive airflow sensing and energy harvesting devices.
