Search NASA⌕ Search

SEARCH · Search NASA

Results for “Black Silicon”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2

Medicine Delivery Device with Integrated Sterilization and Detection

Sterile delivery devices can be created by integrating a medicine delivery instrument with surfaces that are coated with germicidal and anti-fouling material. This requires that a large-surface-area template be developed within a constrained volume to ensure good contact between the delivered medicine and the germicidal material. Both of these can be integrated using JPL-developed silicon nanotip or cryo-etch black silicon technologies with atomic layer deposition (ALD) coating of specific germicidal layers. The application of semiconductor processing techniques and technologies to the problems of fluid manipulation and delivery has enabled the integration of chemical, electrical, and mechanical manipulation of samples all within a single microfluidic device. This approach has been successfully applied at JPL to the automated processing, detection, and analysis of minute quantities (parts per trillion level) of biomaterials to develop instruments for in situ exploration or extraterrestrial bodies. The same nanofabrication techniques that are used to produce a microfluidics device are also capable of synthesizing extremely high-surface-area templates in precise locations, and coating those surfaces with conformal films to manipulate their surface properties. This methodology has been successfully applied at JPL to produce patterned and coated silicon nanotips (also known as black silicon) to manipulate the hydrophilicity of surfaces to direct the spreading of fluids in microdevices. JPL's ALD technique is an ideal method to produce the highly conformal coatings required for this type of application. Certain materials, such as TiO2, have germicidal and anti-fouling properties when they are illuminated with UV light. The proposed delivery device contacts medicine with this high-surface-area black silicon surface coated with a thin-film germicidal deposited conformally with ALD. The coating can also be illuminated with ultraviolet light for the purpose of sterilization or identification of the medicine itself. This constrained volume that is located immediately prior to delivery into a patient, ensures that the medicine delivery device is inherently sterile. An additional benefit to integrating a high-surface-area template within the fluid channel of a medicine delivery device is that one can envision a number of different functional coatings that could facilitate the capture and analysis of either microbial contaminants or the medicine itself. For example, one could attach antibodies or some other binding agent with a specific affinity to the silicon nanotip template. Once a target molecule or microbe is bound to the high-surface- area template, one could use an optical analytical technique such as fluorescence or adsorption to determine the identity and potentially the concentration of the species of interest. By illuminating the bound species from the back, it may also be possible to probe only the molecules with an evanescent wave, making detection of the species from the front side of the device much simpler.

Shearn, Michael J.↗

CubeSat Infrared Atmospheric Sounder (CIRAS) NASA InVEST Technology Demonstration

Infrared sounders measure the upwelling radiation of the Earth in the Midwave Infrared (MWIR) and Longwave Infrared (LWIR) region of the spectrum with global daily coverage from space. The observed radiances are assimilated into weather forecast models and used to retrieve lower tropospheric temperature and water vapor for climate studies. There are several operational sounders today including the Atmospheric Infrared Sounder (AIRS) on Aqua, the Crosstrack Infrared Sounder (CrIS) on Suomi NPP and JPSS, and the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp spacecraft. The CubeSat Infrared Atmospheric Sounder (CIRAS) is a NASA In-flight Validation of Earth Science Technologies (InVEST) program to demonstrate three new instrument technologies in an imaging sounder configuration. The first is a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The detectors are hybridized to a commercial ROIC and commercial camera electronics. The second technology is a MWIR Grating Spectrometer (MGS) designed to provide imaging spectroscopy for atmospheric sounding in a CubeSat volume. The MGS employs an immersion grating or grism, has no moving parts, and is based on heritage spectrometers including the OCO-2. The third technology is a Black Silicon infrared blackbody calibration target. The Black Silicon offers very low reflectance over a broad spectral range on a flat surface and is more robust than carbon nanotubes. JPL will also develop the mechanical, electronic and thermal subsystems for the CIRAS payload. The spacecraft will be a commercially available CubeSat. The integrated system will be a complete 6U CubeSat capable of measuring temperature and water vapor profiles with good lower tropospheric sensitivity. The low cost of CIRAS enables multiple units to be flown to improve temporal coverage or measure 3D Atmospheric Motion Vector (AMV) winds. CIRAS will launch in 2019 and is only a technology demonstration. However, what we learn will benefit future instruments that support operational weather forecasting and climate studies.

Pagano, Thomas S.↗

Orientation-dependent etching of silicon by fluorine molecules: A quantum chemistry computational study

Anisotropic etching is a widely used process in semiconductor manufacturing, in particular, for micro- and nanoscale texturing of silicon surfaces for black silicon production. The typical process of plasma-assisted etching uses energetic ions to remove materials in the vertical direction, creating anisotropic etch profiles. Plasmaless anisotropic etching, considered here, is a less common process that does not use ions and plasma. The anisotropy is caused by the unequal etching rates of different crystal planes; the etching process, thus, proceeds in a preferred direction. In this paper, we have performed quantum chemistry modeling of gas-surface reactions involved in the etching of silicon surfaces by molecular fluorine. The results confirm that orientation-dependent etch rates are the reason for anisotropy. The modeling of F 2 dissociative chemisorption on F-terminated silicon surfaces shows that Si–Si bond breaking is slow for the Si(111) surface, while it is fast for Si(100) and Si(110) surfaces. Both Si(100) and Si(110) surfaces incorporate a larger number of fluorine atoms resulting in Si–Si bonds having a larger amount of positive charge, which lowers the reaction barrier of F 2 dissociative chemisorption, yielding a higher etch rate for Si(100) and Si(110) surfaces compared to Si(111) surfaces. Molecular dynamics modeling of the same reactions has shown that the chosen reactive bond order potential does not accurately reproduce the lower reaction barriers for F 2 dissociative chemisorption on Si(100) and Si(100) surfaces. Furthermore, reparameterization is necessary to model the anisotropic etching process that occurs at lower temperatures.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA Tech Briefs, December 2011

Topics covered include: 1) SNE Industrial Fieldbus Interface; 2) Composite Thermal Switch; 3) XMOS XC-2 Development Board for Mechanical Control and Data Collection; 4) Receiver Gain Modulation Circuit; 5) NEXUS Scalable and Distributed Next-Generation Avionics Bus for Space Missions; 6) Digital Interface Board to Control Phase and Amplitude of Four Channels; 7) CoNNeCT Baseband Processor Module; 8) Cryogenic 160-GHz MMIC Heterodyne Receiver Module; 9) Ka-Band, Multi-Gigabit-Per-Second Transceiver; 10) All-Solid-State 2.45-to-2.78-THz Source; 11) Onboard Interferometric SAR Processor for the Ka-Band Radar Interferometer (KaRIn); 12) Space Environments Testbed; 13) High-Performance 3D Articulated Robot Display; 14) Athena; 15) In Situ Surface Characterization; 16) Ndarts; 17) Cryo-Etched Black Silicon for Use as Optical Black; 18) Advanced CO2 Removal and Reduction System; 19) Correcting Thermal Deformations in an Active Composite Reflector; 20) Umbilical Deployment Device; 21) Space Mirror Alignment System; 22) Thermionic Power Cell To Harness Heat Energies for Geothermal Applications; 23) Graph Theory Roots of Spatial Operators for Kinematics and Dynamics; 24) Spacesuit Soft Upper Torso Sizing Systems; 25) Radiation Protection Using Single-Wall Carbon Nanotube Derivatives; 26) PMA-PhyloChip DNA Microarray to Elucidate Viable Microbial Community Structure; 27) Lidar Luminance Quantizer; 28) Distributed Capacitive Sensor for Sample Mass Measurement; 29) Base Flow Model Validation; 30) Minimum Landing Error Powered-Descent Guidance for Planetary Missions; 31) Framework for Integrating Science Data Processing Algorithms Into Process Control Systems; 32) Time Synchronization and Distribution Mechanisms for Space Networks; 33) Local Estimators for Spacecraft Formation Flying; 34) Software-Defined Radio for Space-to-Space Communications; 35) Reflective Occultation Mask for Evaluation of Occulter Designs for Planet Finding; and 36) Molecular Adsorber Coating

Source record↗

Exoplanet Coronagraph Shaped Pupil Masks and Laboratory Scale Star Shade Masks: Design, Fabrication and Characterization

Star light suppression technologies to find and characterize faint exoplanets include internal coronagraph instruments as well as external star shade occulters. Currently, the NASA WFIRST-AFTA mission study includes an internal coronagraph instrument to find and characterize exoplanets. Various types of masks could be employed to suppress the host star light to about 10 -9 level contrast over a broad spectrum to enable the coronagraph mission objectives. Such masks for high contrast internal coronagraphic imaging require various fabrication technologies to meet a wide range of specifications, including precise shapes, micron scale island features, ultra-low reflectivity regions, uniformity, wave front quality, achromaticity, etc. We present the approaches employed at JPL to produce pupil plane and image plane coronagraph masks by combining electron beam, deep reactive ion etching, and black silicon technologies with illustrative examples of each, highlighting milestone accomplishments from the High Contrast Imaging Testbed (HCIT) at JPL and from the High Contrast Imaging Lab (HCIL) at Princeton University. We also present briefly the technologies applied to fabricate laboratory scale star shade masks.

black silicon↗

Surface Seal for Carbon Parts

Surface pores in parts made of graphite or reinforced-carbon/ carbon materials are sealed by a silicon carbide-based coating. Coating inhibits subsurface oxidation and lengthens part life. Starting material for coating is graphite felt, which is converted to silicon carbide felt by processing it according to a prescribed time/temperature schedule. Converted felt is pulverized in a ball mill and resulting powder is mixed with an equal weight of black silicon carbide powder. Powder mixture is combined with an equal weight of adhesive to form a paste.

Shuford, D. M.↗

NASA Tech Briefs, March 2013

Topics covered include: Remote Data Access with IDL Data Compression Algorithm Architecture for Large Depth-of-Field Particle Image Velocimeters Vectorized Rebinning Algorithm for Fast Data Down-Sampling Display Provides Pilots with Real-Time Sonic-Boom Information Onboard Algorithms for Data Prioritization and Summarization of Aerial Imagery Monitoring and Acquisition Real-time System (MARS) Analog Signal Correlating Using an Analog-Based Signal Conditioning Front End Micro-Textured Black Silicon Wick for Silicon Heat Pipe Array Robust Multivariable Optimization and Performance Simulation for ASIC Design; Castable Amorphous Metal Mirrors and Mirror Assemblies; Sandwich Core Heat-Pipe Radiator for Power and Propulsion Systems; Apparatus for Pumping a Fluid; Cobra Fiber-Optic Positioner Upgrade; Improved Wide Operating Temperature Range of Li-Ion Cells; Non-Toxic, Non-Flammable, -80 C Phase Change Materials; Soft-Bake Purification of SWCNTs Produced by Pulsed Laser Vaporization; Improved Cell Culture Method for Growing Contracting Skeletal Muscle Models; Hand-Based Biometric Analysis; The Next Generation of Cold Immersion Dry Suit Design Evolution for Hypothermia Prevention; Integrated Lunar Information Architecture for Decision Support Version 3.0 (ILIADS 3.0); Relay Forward-Link File Management Services (MaROS Phase 2); Two Mechanisms to Avoid Control Conflicts Resulting from Uncoordinated Intent; XTCE GOVSAT Tool Suite 1.0; Determining Temperature Differential to Prevent Hardware Cross-Contamination in a Vacuum Chamber; SequenceL: Automated Parallel Algorithms Derived from CSP-NT Computational Laws; Remote Data Exploration with the Interactive Data Language (IDL); Mixture-Tuned, Clutter Matched Filter for Remote Detection of Subpixel Spectral Signals; Partitioned-Interval Quantum Optical Communications Receiver; and Practical UAV Optical Sensor Bench with Minimal Adjustability.

Source record↗

High Contrast Internal and External Coronagraph Masks Produced by Various Techniques

Masks for high contrast internal and external coronagraphic imaging require a variety of masks depending on different architectures to suppress star light. Various fabrication technologies are required to address a wide range of needs including gradient amplitude transmission, tunable phase profiles, ultra-low reflectivity, precise small scale features, and low-chromaticity. We present the approaches employed at JPL to produce pupil plane and image plane coronagraph masks, and lab-scale external occulter type masks by various techniques including electron beam, ion beam, deep reactive ion etching, and black silicon technologies with illustrative examples of each. Further development is in progress to produce circular masks of various kinds for obscured aperture telescopes.

Phase Induced Amplitude Apodization Complex Mask C↗

Measurement Approach and Design of the CubeSat Infrared Atmospheric Sounder (CIRAS)

The CubeSat Infrared Atmospheric Sounder (CIRAS) will measure upwelling infrared radiation of the Earth in the MWIR region of the spectrum from space on a CubeSat. The observed radiances can be assimilated into weather forecast models and be used to retrieve lower tropospheric temperature and water vapor for climate studies. Multiple units can be flown to improve temporal coverage or in formation to provide new data products including 3D motion vector winds. CIRAS incorporates key new instrument technologies including a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The detectors are hybridized to a commercial ROIC and commercial camera electronics. The second key technology is an MWIR Grating Spectrometer (MGS) designed to provide imaging spectroscopy for atmospheric sounding in a CubeSat volume. The MGS has no moving parts and includes an immersion grating to reduce the volume and reduce distortion. The third key technology is an infrared blackbody fabricated with black silicon to have very high emissivity in a flat plate construction. JPL will also develop the mechanical, electronic and thermal subsystems for CIRAS, while the spacecraft will be a commercially available CubeSat. The integrated system will be a complete 6U CubeSat capable of measuring temperature and water vapor profiles with good lower tropospheric sensitivity. The CIRAS is the first step towards the development of an Earth Observation Nanosatellite Infrared (EON-IR) capable of meeting the replacement needs of the CrIS on JPSS.

Pagano, Thomas S.↗

Design and Development of the CubeSat Infrared Atmospheric Sounder (CIRAS

The CubeSat Infrared Atmospheric Sounder (CIRAS) is a NASA Earth Science Technology Office (ESTO) sponsored mission to demonstrate key technologies used in very high spectral resolution infrared remote sensing of Earth’s atmosphere from space. CIRAS was awarded under the ESTO In-flight Validation of Earth Science Technologies (InVEST) program in 2015 and is currently under development at NASA JPL with key subsystems being developed by industry. CIRAS incorporates key new instrument technologies including a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The second key technology is an MWIR Grating Spectrometer (MGS) designed to provide imaging spectroscopy for atmospheric sounding in a CubeSat volume. The MGS is under development by Ball Aerospace with the grating and slit developed by JPL. The third key technology is an infrared blackbody fabricated with JPL’s black silicon to have very high emissivity in a flat plate construction. JPL will also develop the mechanical, electronic and thermal subsystems for CIRAS, while the spacecraft will be a 6U CubeSat developed by Blue Canyon Technologies. This paper provides an overview of the design and acquisition approach, and provides a status of the current development.

Vengel, Tony↗

Technology Development in Support of Hyperspectral Infrared Atmospheric Sounding in a CubeSat

Hyperspectral infrared sounding in a CubeSat will provide a new dimension to the current suite of IR sounders by allowing measurements at multiple times of day and enabling formation flying of IR sounders for new data products such as Atmospheric Motion Vector (AMV) winds. This paper focuses on technology development during the CubeSat Infrared Atmospheric Sounder (CIRAS) project sponsored by the NASA Earth Science Technology Office (ESTO), and coincident studies by the NOAA Office of Projects, Planning, and Analysis (OPPA). The CIRAS approach incorporates key new instrument technologies developed at JPL’s Microdevices Lab (MDL) including a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The second key technology is an MWIR Grating Spectrometer (MGS) designed by Ball Aerospace with a JPL MDL slit and immersion grating to provide hyperspectral infrared imaging in a CubeSat volume. The third key technology is a blackbody calibration target fabricated with MDL’s black silicon to have very high emissivity in a flat plate construction. JPL has completed design and breadboard of the mechanical, electronic and thermal subsystems for CIRAS payload including a HOT-BIRD FPA, with filters in a dewar and a breadboard of the electronics and scan mirror assembly. Blue Canyon Technologies, developer of the CIRAS 6U CubeSat, completed the Final Design Review for the spacecraft.

Yee, Karl↗

Ambient Performance Testing of the CubeSat Infrared Atmospheric Sounder (CIRAS)

Hyperspectral infrared measurements of Earth’s atmosphere from space have proven their value for weather forecasting, climate science and atmospheric composition. The CubeSat Infrared Atmospheric Sounder (CIRAS) instrument will demonstrate a fully functional infrared temperature, water vapor and carbon monoxide sounder in a CubeSat sized volume for at least an order of magnitude lower cost than legacy systems. Design for a CubeSat significantly reduces cost of access to space and enables flight in a constellation to reduce revisit time and enable new measurements including 3D winds. A technology demonstration of CIRAS is currently under development at JPL. The effort has completed integration and ambient testing of a high fidelity brassboard, complete with the flight configured optics assembly developed by Ball Aerospace with a JPL Immersion Grating and Black Silicon Entrance Slit. The brassboard includes a flight-configured High Operating Temperature Barrier Infrared Detector (HOT-BIRD) mounted in an Integrated Dewar Cryocooler Assembly (IDCA), enabling testing in the ambient environment. Ambient testing included radiometric testing of the system to characterize the instrument operability and NEdT. Spatial testing was performed to characterize the system line spread function (LSF) in two axes and report FWHM of the LSF. Spectral testing involved an air path test to characterize the spectral/spatial transformation matrix, and an etalon was used to measure the Spectral Response Functions (SRFs). Results of the testing show the CIRAS performs exceptionally well and meets the key performance required of the system. The end result of testing is the CIRAS instrument now meets TRL 4 with confidence in a brassboard configuration ready for thermal vacuum (TVac) testing necessary to achieve TRL 5 for the system.

Wilson, Robert C.↗

Superconducting qubit devices based on metal silicides

A qubit device for use in a quantum computing environment includes a semiconductor substrate, an insulating layer disposed on at least a portion of an upper surface of the substrate, and a transition metal silicide (TMSi) heterojunction disposed on at least a portion of an upper surface of the insulating layer. The TMSi heterojunction includes a link layer and at least first and second TMSi regions coupled with the link layer. The link layer may include a normal conductor, thereby forming a superconductor-normal conductor-superconductor (SNS) junction, or a geometric constriction, thereby forming a superconductor-geometric constriction-superconductor (ScS) junction. The link layer may form at least a portion of a channel including intrinsic or doped silicon.

Black, Charles T.↗

Electrically conductive, black thermal control coatings for space craft application. II - Silicone matrix formulation

Five black electrically conductive thermal-control coatings have been formulated and tested for application on the Galileo spacecraft. The coatings consisted of organic and inorganic systems applied on titanium and aluminum surfaces. The coatings were tested under simulated space environment conditions. Coated specimens were subjected to thermal radiation and convective and conductive heating from -196 to 538 C. Mechanical, physical, thermal, electrical, and optical characteristics, formulation, mixing, application, surface preparation of substrates, and a method of determining electrical resistance are presented for the silicone matrix formulation designated as GF-580.

Hribar, V. F.↗

Tuning working potential of silicon-phosphorus anode via microstructure control for high-energy lithium-ion batteries

The primary research on anode materials of lithium-ion batteries have been focused on increasing the specific capacity, while the working potential that is also closely related to the practical energy density of batteries has been paid much less attention. In this paper, starting from micrometer-sized silicon and black phosphorus, we have reported a high-energy silicon-phosphorus/carbon anode (denoted as mSPC) via a high-energy ball milling process, which demonstrates an average discharge working potential of 0.3 volts versus lithium, together with a high reversible capacity of > 2000 mAh/g, high initial coulombic efficiency of 84%, excellent cycle stability, and superior rate capability up to 15 A/g. Furthermore, in situ focused-ion-beam scanning electron microscopy reveals that the volume change of the mSPC anode during repeated (de) lithiation is effectively alleviated. In contrast, starting from nanometer-sized silicon, the resulted anode (denoted as nSPC) not only presents a lower reversible capacity (~1200 mAh/g), but also exhibits a higher charge/discharge working potential, leading to reduced energy density. Our results indicate the importance of composition/structure control in tailoring the working potential and specific capacity of alloying-type anodes towards high-energy lithium-ion batteries.

25 ENERGY STORAGE↗

Characterization of the Earth Radiation Budget Experiment radiometers

The Earth Radiation Budget Experiment (ERBE) scanning radiometers were used to measure the earth's radiation fields during the period November 1984 through February 1990. The ERBE radiometric packages were placed into orbit aboard the Earth Radiation Budget Satellite (ERBS) and the NOAA-9 and NOAA-10 spacecraft platforms. In each radiometric package, thermistor bolometers were used as detection elements for the broadband total (0,2 - 50,0 microns), shortwave (0,2 - 5,0 microns), and longwave (5,0 - 50,0 microns) spectral regions. Flight calibration facilities were built into each of the spacecraft radiometric packages. The flight facilities consisted of black bodies, tungsten lamps, and silicon photodiodes. The black bodies and tungsten lamps were found to be reliable at precision levels approaching 0,5 percent over a five-year period. The photodiodes were found to degrade more than 2 percent during the first year in orbit. In this paper, the flight calibration systems for the ERBE scanning radiometers are described along with the resultant measurements.

Lee, R. B., III↗

Towards a 700 mV silicon solar cell

The key to improved silicon solar cell performance lies in increasing cell open circuit voltage. Not only does improved voltage direclty increase cell efficiency, but it also increases the limiting value of fill factor and decreases the temperature sensitivity of the cell. Limits on attainable open circuit voltage are not well defined. A thermodynamic limit of 850 mV exists for black body silicon cells, with 700 mV long regarded as a practical limit. This paper describes experimental work which has resulted in experimental devices with open circuit voltages approaching 700 mV. Values up to 694 (AM0, 25 C) have been demonstrated. The cells are similar in structure to conventional p-n junction cells, but particular attention is paid to passivating the entire top surface of the cell, including regions under the top contact.

Green, M. A.↗

Survey Of Infrared-Absorbing Coatings

Carbon black and silicon carbide grit low reflectance additives. Report presents results of survey of candidate materials for use as attenuators of stray radiation in far-infrared telescopes. More than 40 reflectance spectra at 17 degrees incidence, in wave-length range from 20 to 500 micrometer, obtained from variety of coatings, binders, and additives.

Smith, Sheldon M.↗