Areas packed with dense foliage. Mile-deep mines and tunnels. Urban canyons. Indoor environments. Global Positioning System (GPS) technology has long been a boon to location tracking of aerial, terrestrial and aquatic vehicles — as well as to people in motion — but in many cases it can’t function with a high degree of reliability, either because the GPS signal is somehow obstructed, or worse, is jammed or spoofed.
Delivering higher precision and higher reliability in GPS-denied environments — as well as immunity to jamming and spoofing — positioning, navigation and timing (PNT) represents the next evolutionary step in location positioning and tracking. With PNT so critical to a range of defense, commercial and industrial applications — and with sensors the building blocks of PNT solutions —the MEMS Sensors Industry Group, a SEMI Technology Community, is ensuring that our members play a transformative role in PNT innovations.
We’ve secured $14.9 million in research dollars for PNT R D over the past 18 months, marking Phase I of a project funded through a public-private consortium with the U.S. Army Research Laboratory (ARL). With the typical funding structured as a 50/50 cost share with the industry participant, the research dollars go farther, and the level of commitment that each recipient makes is more pronounced.
As we look ahead to Phase II of the MSIG PNT R D project, the details of which we’ll announce later this year, we’d like to reflect on the companies and research labs that won bids through a competitive process supported by the SEMI-MSIG PNT Technical Advisory Council and the SEMI-MSIG PNT Governing Council. Winners submitted proposals that both met our criteria for advancing PNT technologies relative to mobility, size and weight, and that laid a path toward greater cost efficiency and lower product price.
“PNT doesn’t displace GPS,” said Tim Brosnihan, executive director of SEMI-MSIG. “Rather, getting the two technologies to work together improves position and tracking. While current PNT solutions use inertial measurement units, or IMUs, to effectively maintain positioning accuracy in the absence of a GPS signal, it’s also true that accumulated bias and noise-related errors in the IMUs make positional determination unreliable.
Like most great pairings, GPS and PNT can work together. We can use IMUs when GPS is unavailable, and when GPS returns, it can be used to reset the IMU errors. So when the GPS signal is lost again, the IMU can maintain navigation and location.
“We’re focusing this PNT project on technologies that will allow accurate positional determination in the absence of a reliable GPS signal for prolonged periods,” added Brosnihan.
Here are snapshots of the 10 companies and research institutions that won awards for their PNT-focused developments.
Analog Devices is developing an optimal size, weight, power, and cost (SWaP-C) solution for applications requiring high-accuracy navigation and uncompromised reliability. The company’s mode-matched navigation-grade gyroscope with system ID leverages an innovative sensor and its associated process design, a robust high-volume manufacturing flow, and system-control algorithms to achieve very high-performance (0.01 degree/hour bias instability and 0.005 degree/√hr angle random walk).
Carnegie Mellon University (CMU) is developing a CMOS MEMS high-stability accelerometer through machine learning (ML). If embedded in footwear, these ML-optimized accelerometers could be used in personal navigation. If embedded in a golf ball, baseball or hockey puck, the accelerometer could extract the trajectory of the object in motion by measuring its shock (force). The CMU device validates state-of-the-art performance of the university’s high-dynamic-range accelerometer systems-on-chip. It also validates and tests ML models by measuring the accelerometer and auxiliary sensor output over long time periods (e.g., 1 hour, 10 hours, days) to collect independent long-duration time-series data. By modeling drift from environmental influences — along with possible overall system changes from extreme events, such as high-temperature excursions and shock — designers can dramatically reduce navigation errors to support more accurate navigation over longer time periods.
GE Research is developing a novel MEMS gyrocompass that will enable high-end north-finding systems, traditionally unaffordable for automotive and consumer applications. The device will be available in mass-market applications such as robotics and autonomous vehicle navigation in GPS-denied environments. The MEMS gyrocompass enables a 10x reduction in SWAP-C with high accuracy. An additional benefit of this work is that GE will offer a foundry service process development kit (PDK) for its Polaris MEMS process, speeding the development and manufacture of MEMS devices in an advanced processing facility.
Georgia Institute of Technology is developing high-aspect-ratio monocrystalline silicon carbide-on-Insulator (SiCOI) MEMS devices that will reduce navigation angle errors, potentially making widescale pedestrian navigation available in mass-market applications such as smartwatches and smartphones. The platform for ultra-high-performance bulk acoustic wave (BAW) gyroscopes and timing resonators will feature material properties that allow a much better structural symmetry and a higher-resonant quality factor (Q) than silicon MEMS (Si MEMS).
Honeywell is working to enhance the navigation accuracy of commercial and military vehicles in GPS-denied environments through an innovation that dramatically improves the performance of a MEMS IMU by both refining candidate ML algorithms, including recurrent neural networks (RNNs), and by combining deep neural network (DNN)-based calibration and sensor fusion algorithms.
PARC is developing a new materials platform for photonic integrated circuits (PIC). Aluminum gallium nitride (AlGaN), an ultra-wide bandgap semiconductor, is epitaxially grown to produce single-crystal layers for fabrication of optical components, such as waveguides and micro-ring resonators for optical signal processing. The project includes design and fabrication of specialized laser diodes at wavelengths needed to probe qubits based on atomic ions (e.g., strontium and ytterbium). The new platform offers several benefits:
low optical loss from the ultraviolet (UV) to infrared spectral bands
excellent non-linear optical properties for efficient frequency-generation processes (e.g., optical frequency combs); and
enabling technology to realize compact, field-deployable quantum systems for PNT applications, such as ultra-fast distance measurements, microcombs for optical atomic clocks, photonic radar, optical coherence tomography, and coherent communications — all applications that benefit from the lower cost and small chip size of these integrated photonic circuits
By expanding its proprietary EpiSeal encapsulation process to include new materials and topologies, SiTime is developing low-impedance and low-noise MEMS resonators with an ultra-stable wafer-level package. Because these novel MEMS resonators are highly reliable and very compact — while using less power and providing lower RF noise — they’re ideal for 5G RF timing applications, IoT devices, and smart vehicles.
Teledyne Scientific Imaging (CSAC project) is conducting a study to identify paths to reduce the cost of battery-operated chip scale atomic clocks (CSAC) that provide affordable precision timing for denied environments. The project goal is to identify viable paths of reducing cost by an order of magnitude, without sacrificing performance. In addition to exploring design and manufacturability solutions, project researchers are performing short loop experiments as proof-of-concept validation.
Through a second award, Teledyne Scientific (IMU project) is advancing packaging and integration for compact, navigation-grade six degrees of freedom (DOF) MEMS IMUs. Featuring reduced bias instabilities associated with packaging stresses and ambient temperature influences, the Teledyne Scientific IMUs promote environmentally robust low-stress packaging of wafer-level vacuum packaged (WLVP) MEMS gyro resonators, facilitating a lower-cost, smaller and more accurate IMU for performance-driven PNT applications.
Twinleaf is developing a new light source module ideally suited for integration directly into quantum sensors. This project integrates a bright, tunable distributed Bragg reflector (DBR) near infrared (IR) 795nm wavelength laser made by the project’s subcontractor (Photodigm) into a package that locks the laser to an atomic reference line in a microfabricated vapor cell. The laser module’s high-output intensity and low magnetic signature will enable breakthrough performance levels for Twinleaf’s magnetometer and other quantum sensors requiring the light source integrated into the sensor module.
Request for Proposal for Phase II of SEMI-MSIG PNT Program Opens Q4 2021
SEMI-MSIG will accept request for proposal (RFP) submissions for Phase II of its PNT program starting in Q4 2021. This year, in addition to funding IMU and timing device projects, MSIG will also consider proposals on imaging-based navigation solutions. If you’d like to submit for Phase II, sign up to receive more information on the RFP by visiting SEMI’s R D Programs page. You can also connect with Paul Carey by email, [email protected] or LinkedIn.
Paul Carey, Ph.D., is the director of the MEMS Sensors Industry Group. With deep domain expertise in X-ray imaging backplane platforms — and their supply-chain technologies such as flexible substrates, laser annealing for semiconductors and silicides, thin film transistors (TFT) for flexible OLED displays, and polysilicon-on-plastic TFT technology — Carey has held technical leadership positions at dpiX, Applied Materials, and Lawrence Livermore National Laboratory. He received a double-major B.S. from UC Berkeley in Electronical Engineering and Computer Science (EECS), and Materials Science and Engineering (MSE). Carey holds an M.S. in EECS from UC Berkeley and a Ph.D. in MSE from Stanford University.
