Terahertz(THz)detectors using MEMS resonators have attracted great interests owing to their high sensitivity,rapid response,and room-temperature operation capability.For easy integration with CMOS circuits,silicon(Si)...Terahertz(THz)detectors using MEMS resonators have attracted great interests owing to their high sensitivity,rapid response,and room-temperature operation capability.For easy integration with CMOS circuits,silicon(Si)based MEMS detectors are highly desirable.Here we report an uncooled THz bolometer using doubly-clamped Si on insulator(SOI)MEMS beam resonator with piezoresistive readout.When external heat is applied to the MEMS beam,the resonance frequency shifts owing to the thermal strain in the beam,demonstrating a thermal responsivity up to 149W^(−1).SOI MEMS resonators exhibit a thermal response time of about 88μs,which is over 3 times faster than that of GaAs MEMS detectors.Furthermore,electrical readout of the MEMS vibrations is achieved by using the piezoresistive effect of Si,offering a low frequency noise density of 2.7 mHz/√Hz,and subsequently a noise equivalent power(NEP)of about 36 pW/√Hz for the current devices.Optical measurement using a FTIR spectrometer shows that SOI MEMS bolometers has a broadband THz response across 1-10 THz range.These results demonstrate that SOI MEMS bolometer features fast response and high sensitivity,while also being compact,broadband,and CMOS-compatible,highlighting its strong potential for advanced THz spectroscopy and imaging applications.展开更多
基金supported by the A-STEP program of JST,and KAKENHI from JSPS(21K04151,24K00937)。
文摘Terahertz(THz)detectors using MEMS resonators have attracted great interests owing to their high sensitivity,rapid response,and room-temperature operation capability.For easy integration with CMOS circuits,silicon(Si)based MEMS detectors are highly desirable.Here we report an uncooled THz bolometer using doubly-clamped Si on insulator(SOI)MEMS beam resonator with piezoresistive readout.When external heat is applied to the MEMS beam,the resonance frequency shifts owing to the thermal strain in the beam,demonstrating a thermal responsivity up to 149W^(−1).SOI MEMS resonators exhibit a thermal response time of about 88μs,which is over 3 times faster than that of GaAs MEMS detectors.Furthermore,electrical readout of the MEMS vibrations is achieved by using the piezoresistive effect of Si,offering a low frequency noise density of 2.7 mHz/√Hz,and subsequently a noise equivalent power(NEP)of about 36 pW/√Hz for the current devices.Optical measurement using a FTIR spectrometer shows that SOI MEMS bolometers has a broadband THz response across 1-10 THz range.These results demonstrate that SOI MEMS bolometer features fast response and high sensitivity,while also being compact,broadband,and CMOS-compatible,highlighting its strong potential for advanced THz spectroscopy and imaging applications.
