Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers
We present a wafer-level vacuum-packaged (WLVP) translatory micro-electro-mechanical system (MEMS) actuator developed for a compact near-infrared-Fourier transform spectrometer (NIR-FTS) with 800–2500 nm spectral bandwidth and signal-nose-ratio (SNR) > 1000 in the smaller bandwidth range (1200–25...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-09-01
|
| Series: | Micromachines |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-666X/11/10/883 |
| _version_ | 1797552895250399232 |
|---|---|
| author | Thilo Sandner Eric Gaumont Thomas Graßhoff Andreas Rieck Tobias Seifert Gerald Auböck Jan Grahmann |
| author_facet | Thilo Sandner Eric Gaumont Thomas Graßhoff Andreas Rieck Tobias Seifert Gerald Auböck Jan Grahmann |
| author_sort | Thilo Sandner |
| collection | DOAJ |
| description | We present a wafer-level vacuum-packaged (WLVP) translatory micro-electro-mechanical system (MEMS) actuator developed for a compact near-infrared-Fourier transform spectrometer (NIR-FTS) with 800–2500 nm spectral bandwidth and signal-nose-ratio (SNR) > 1000 in the smaller bandwidth range (1200–2500 nm) for 1 s measuring time. Although monolithic, highly miniaturized MEMS NIR-FTSs exist today, we follow a classical optical FT instrumentation using a resonant MEMS mirror of 5 mm diameter with precise out-of-plane translatory oscillation for optical path-length modulation. Compared to highly miniaturized MEMS NIR-FTS, the present concept features higher optical throughput and resolution, as well as mechanical robustness and insensitivity to vibration and mechanical shock, compared to conventional FTS mirror drives. The large-stroke MEMS design uses a fully symmetrical four-pantograph suspension, avoiding problems with tilting and parasitic modes. Due to significant gas damping, a permanent vacuum of ≤3.21 Pa is required. Therefore, an MEMS design with WLVP optimization for the NIR spectral range with minimized static and dynamic mirror deformation of ≤100 nm was developed. For hermetic sealing, glass-frit bonding at elevated process temperatures of 430–440 °C was used to ensure compatibility with a qualified MEMS processes. Finally, a WLVP MEMS with a vacuum pressure of ≤0.15 Pa and <i>Q</i> ≥ 38,600 was realized, resulting in a stroke of 700 µm at 267 Hz for driving at 4 V in parametric resonance. The long-term stability of the 0.2 Pa interior vacuum was successfully tested using a Ne fine-leakage test and resulted in an estimated lifetime of >10 years. This meets the requirements of a compact NIR-FTS. |
| first_indexed | 2024-03-10T16:07:31Z |
| format | Article |
| id | doaj.art-59876b9d62dd43bc8c0cc8b5224a03f6 |
| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-10T16:07:31Z |
| publishDate | 2020-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Micromachines |
| spelling | doaj.art-59876b9d62dd43bc8c0cc8b5224a03f62023-11-20T14:46:16ZengMDPI AGMicromachines2072-666X2020-09-01111088310.3390/mi11100883Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT SpectrometersThilo Sandner0Eric Gaumont1Thomas Graßhoff2Andreas Rieck3Tobias Seifert4Gerald Auböck5Jan Grahmann6Fraunhofer Institute for Photonic Microsystems (FhG-IPMS), 01109 Dresden, GermanyFraunhofer Institute for Photonic Microsystems (FhG-IPMS), 01109 Dresden, GermanyFraunhofer Institute for Photonic Microsystems (FhG-IPMS), 01109 Dresden, GermanyFraunhofer Institute for Photonic Microsystems (FhG-IPMS), 01109 Dresden, GermanyFraunhofer Institute for Electronic Nanosystems (FhG-ENAS), 09126 Chemnitz, GermanySilicon Austria Labs (SAL), 9524 Villach, AustriaFraunhofer Institute for Photonic Microsystems (FhG-IPMS), 01109 Dresden, GermanyWe present a wafer-level vacuum-packaged (WLVP) translatory micro-electro-mechanical system (MEMS) actuator developed for a compact near-infrared-Fourier transform spectrometer (NIR-FTS) with 800–2500 nm spectral bandwidth and signal-nose-ratio (SNR) > 1000 in the smaller bandwidth range (1200–2500 nm) for 1 s measuring time. Although monolithic, highly miniaturized MEMS NIR-FTSs exist today, we follow a classical optical FT instrumentation using a resonant MEMS mirror of 5 mm diameter with precise out-of-plane translatory oscillation for optical path-length modulation. Compared to highly miniaturized MEMS NIR-FTS, the present concept features higher optical throughput and resolution, as well as mechanical robustness and insensitivity to vibration and mechanical shock, compared to conventional FTS mirror drives. The large-stroke MEMS design uses a fully symmetrical four-pantograph suspension, avoiding problems with tilting and parasitic modes. Due to significant gas damping, a permanent vacuum of ≤3.21 Pa is required. Therefore, an MEMS design with WLVP optimization for the NIR spectral range with minimized static and dynamic mirror deformation of ≤100 nm was developed. For hermetic sealing, glass-frit bonding at elevated process temperatures of 430–440 °C was used to ensure compatibility with a qualified MEMS processes. Finally, a WLVP MEMS with a vacuum pressure of ≤0.15 Pa and <i>Q</i> ≥ 38,600 was realized, resulting in a stroke of 700 µm at 267 Hz for driving at 4 V in parametric resonance. The long-term stability of the 0.2 Pa interior vacuum was successfully tested using a Ne fine-leakage test and resulted in an estimated lifetime of >10 years. This meets the requirements of a compact NIR-FTS.https://www.mdpi.com/2072-666X/11/10/883micro-opto-electro-mechanical system (MOEMS)translatory micro mirroroptical wafer-level vacuum package (WLVP)NIR Fourier-transform spectrometerglass-frit wafer bonding |
| spellingShingle | Thilo Sandner Eric Gaumont Thomas Graßhoff Andreas Rieck Tobias Seifert Gerald Auböck Jan Grahmann Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers Micromachines micro-opto-electro-mechanical system (MOEMS) translatory micro mirror optical wafer-level vacuum package (WLVP) NIR Fourier-transform spectrometer glass-frit wafer bonding |
| title | Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers |
| title_full | Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers |
| title_fullStr | Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers |
| title_full_unstemmed | Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers |
| title_short | Wafer-Level Vacuum-Packaged Translatory MEMS Actuator with Large Stroke for NIR-FT Spectrometers |
| title_sort | wafer level vacuum packaged translatory mems actuator with large stroke for nir ft spectrometers |
| topic | micro-opto-electro-mechanical system (MOEMS) translatory micro mirror optical wafer-level vacuum package (WLVP) NIR Fourier-transform spectrometer glass-frit wafer bonding |
| url | https://www.mdpi.com/2072-666X/11/10/883 |
| work_keys_str_mv | AT thilosandner waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers AT ericgaumont waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers AT thomasgraßhoff waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers AT andreasrieck waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers AT tobiasseifert waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers AT geraldaubock waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers AT jangrahmann waferlevelvacuumpackagedtranslatorymemsactuatorwithlargestrokefornirftspectrometers |