Goddard Engineering and Technology Directorate

Unlocking the Power of Micro-Electro Mechanical Systems (MEMS) Capabilities

The microshutter array (MSA) for the Near-Infrared Spectrograph (NIRSpec) instrument was developed and manufactured at the Detector Development Laboratory. Photo Credit: ETD Instrument System and Technology Division, Detector Systems Branch, Goddard Space Flight Center
The microshutter array (MSA) for the Near-Infrared Spectrograph (NIRSpec) instrument was developed and manufactured at the Detector Development Laboratory. Photo Credit: ETD Instrument System and Technology Division, Detector Systems Branch, Goddard Space Flight Center

Revolutionizing Technology Integral to Everyday Life and Space Innovation

Microelectromechanical systems (MEMS), also referred to as Microsystems in Europe, are miniature transducers in the micron or sub-micron scale. These systems are constructed on substrates such as silicon or glass using microfabrication techniques. MEMS technology is integral to numerous applications in everyday life, including wearable sensors in smartwatches, implantable drug delivery systems, automotive sensors for pressure and motion detection, and various space technologies, such as sensors, actuators, detectors, and optical components.

The Detector Development Laboratory (DDL), a state-of-the-art microfabrication facility, was the birthplace of the James Webb Space Telescope (JWST) Microshutter Array and enabled the development of detectors for the more recent Roman Space Telescope (RST). In addition to traditional MEMS applications, Goddard’s Engineering and Technology Directorate (ETD) specializes in several unique areas, such as transition edge sensors, bolometers, X-ray and infrared detectors, and flexible superconducting wires. This team of ETD experts at Goddard is the first group in the world that creates microshutters, which enabled multi-object spectroscopy in space.

DDL offers a wide range of capabilities for developing MEMS devices, including advanced layout design, thin film deposition, and various etching techniques. The facility is also equipped for silicon bulk micromachining, which allows for the precise fabrication of 3D structures on silicon substrates. Furthermore, it provides comprehensive packaging capabilities to ensure the effective integration and protection of MEMS devices within functional subsystems. Specific details of these capabilities include:

  1. Design and simulation: finite element analysis and mask layout design
  2. Lithography: mask making, contact aligner, laser direct writing, E-beam lithography, Stepper
  3. Chemical processing: solvent, acid and base chemical process
  4. Deposition and growth:
    • Chemical vapor deposition (CVD): Plasma Enhanced Chemical Vapor Deposition (PECVD), Atomic Layer Deposition (ALD), and Parylene deposition
    • Physical vapor deposition (PVD): Sputter deposition, E-beam evaporation, and thermal evaporation
    • Electroplating
  5. Etching
    • Wet etching
    • Reactive ion etching (RIE) and deep reactive ion etching
    • Plasma etching
    • Dry vapor etching: XeF2 etching, vapor hydrofluoric etching
  6. Thermal processing: thermal oxidization and annealing
  7. Metrology and characterization
    • Scanning electron microscopy
    • Atomic force microscopy
    • Stylus profilometry
    • Scanning white light interferometry
    • Confocal laser optical profilometry
    • Optical microscopy
    • Ellipsometry
    • Thin film stress measurement
    • Probe station
    • Four-point probe
  8. Packaging
    • Flip-chip bonding
    • Fine placer die bonder
    • Wirebonding
    • Substrate dicing
    • Wafer bonding
  9. Mechanical Finishing: lapping, chemical mechanical polish

Technology Highlights

In addition to the JWST Microshutter Array, the following cutting-edge technologies highlight the MEMS capabilities of the DDL:

Advanced Telescope for High-ENergy Astrophysics

This image shows a full scale ATHENA prototype detector (top) installed in the ground-based testing fixture at Goddard with bumpbonded readout (side) and flexible interconnection cables all fabricated and assembled at NASA Goddard and with project partner NIST, Boulder. Photo Credit: Kazuhiro Sakai
This image shows a full scale ATHENA prototype detector (top) installed in the ground-based testing fixture at Goddard with bumpbonded readout (side) and flexible interconnection cables all fabricated and assembled at NASA Goddard and with project partner NIST, Boulder. Photo Credit: Kazuhiro Sakai

Advanced Lithography Developments

Examples of stepper lithography, the Detector Development Laboratory (DDL) can fabricate 250 nm iso-lines and 350 nm line/space structures. Overlay accuracy is better than +/- 40nm.
Examples of stepper lithography, the Detector Development Laboratory (DDL) can fabricate 250 nm iso-lines and 350 nm line/space structures. Overlay accuracy is better than +/- 40nm.
Image of printed photonic crystal (left), and sub- 10 nm features (right). Overlay accuracy is less than +/- 25nm with typical 500 mm write fields. Electron beam lithography system has a ‘modulated beam moving stage’ function that enables large area periodic structures such as photonic crystals (left), optical waveguides, gratings, etc to be printed “stitching error” free. Image credit: Kevin Denis
Image of printed photonic crystal (left), and sub- 10 nm features (right). Overlay accuracy is less than +/- 25nm with typical 500 mm write fields. Electron beam lithography system has a ‘modulated beam moving stage’ function that enables large area periodic structures such as photonic crystals (left), optical waveguides, gratings, etc to be printed “stitching error” free. Image credit: Kevin Denis

Optical Masks for RST Detector Characterization

Sub-pixel response of the 10um HgCdTe H4RG detectors for Roman Space Telescope is being characterized using the Talbot Effect and processes in the DDL that enable fabrication of a high-precision binary optical mask with high-contrast and deep-etched pinholes that cover less than 20% of the area of a single pixel. The optical pinholes are etched on a gold-coated 100mm silicon wafer with a periodic membrane structure to enable micrometer-scale apertures with high contrast. This work in the Talbot Illuminator test setup has enabled RST scientists to better understand and model the sub-pixel response characteristics of the 302 million pixels in the 18 detectors in the Wide Field Instrument. Photo Credit: Kevin Denis, Ron Hu, Chris Merchant, and Dan Kelly
Sub-pixel response of the 10um HgCdTe H4RG detectors for Roman Space Telescope is being characterized using the Talbot Effect and processes in the DDL that enable fabrication of a high-precision binary optical mask with high-contrast and deep-etched pinholes that cover less than 20% of the area of a single pixel. The optical pinholes are etched on a gold-coated 100mm silicon wafer with a periodic membrane structure to enable micrometer-scale apertures with high contrast. This work in the Talbot Illuminator test setup has enabled RST scientists to better understand and model the sub-pixel response characteristics of the 302 million pixels in the 18 detectors in the Wide Field Instrument. Photo Credit: Kevin Denis, Ron Hu, Chris Merchant, and Dan Kelly

Advancing Readout of Bolometric Detectors

Photograph of a cryogenic detector focal plane assembly. It includes a kilo-pixel transition edge sensor (TES) bolometric detector array, which is mated to a multiplexed cryogenic amplifier (2d- SQUID) via superconducting leads on a fanout board and indium bumps. Photo Credit: Ari Brown
Photograph of a cryogenic detector focal plane assembly. It includes a kilo-pixel transition edge sensor (TES) bolometric detector array, which is mated to a multiplexed cryogenic amplifier (2d- SQUID) via superconducting leads on a fanout board and indium bumps. Photo Credit: Ari Brown

Miniaturized Chemical Detection Platform

Miniaturized chemical detection platform including nanomaterial based chemical detector channels, microheaters, and microscale temperature sensors. Photo Credit: Peter Snapp
Miniaturized chemical detection platform including nanomaterial based chemical detector channels, microheaters, and microscale temperature sensors. Photo Credit: Peter Snapp

Next-Gen Micro-Shutter Array (NGMSA)

The NexGen Micro-Shutter Array (NGMSA), an improvement over the magnetically actuated James Webb Space Telescope (JWST) microshutter array, is an electrically actuated field object selector designed for ultraviolet, visible, and infrared multi-object spectroscopy (MOS). The NGMSA module in the image is designed for Far-UV Off Rowland-circle Telescope for Imaging and Spectroscopy. Photo Credit: Kyowon Kim
The NexGen Micro-Shutter Array (NGMSA), an improvement over the magnetically actuated James Webb Space Telescope (JWST) microshutter array, is an electrically actuated field object selector designed for ultraviolet, visible, and infrared multi-object spectroscopy (MOS). The NGMSA module in the image is designed for Far-UV Off Rowland-circle Telescope for Imaging and Spectroscopy. Photo Credit: Kyowon Kim

Micro-Electro Mechanical Systems (MEMS) capability is managed by ETD’s Instrument System and Technology Division (ISTD). Contact ISTD for more information.