Short-term demonstrations of packaged 4H-SiC junction field-effect transistor (JFET) logic integrated circuits (ICs) at temperatures exceeding 800 °C in air are reported, including a 26-transistor ...11-stage ring oscillator that functioned at 961 °C ambient temperature believed unprecedented for electrical operation of a semiconductor IC. The expanded temperature range should assist temperature acceleration testing/qualification of such ICs intended for long-term use in applications near 500 °C ambient, and perhaps spawn new applications. Ceramic package assembly leakage currents inhibited the determination of some intrinsic SiC device/circuit performance properties at these extreme temperatures, so it is conceivable that even higher operating temperatures might be obtained from SiC JFET ICs by employing packaging and circuit design intended/optimized for T ≥ 800 °C.
Operational testing of prototopye 4H-SiC JFET ICs across an unrivaled ambient temperature span in excess of 1000 °C, from-190 °C to +812 °C, has been demonstrated without any change/adjustment of ...input signal levels or power supply voltages. This unique ability is expected to simplify infusion of this IC technology into a broader range of beneficial applications.
Safe landings are imperative to accomplish NASA’s Artemis goal to enable human exploration on the Moon, including sample collection missions. However, a process known as plume surface interaction ...(PSI) presents a significant hazard to lunar landings. PSI occurs when the engine exhaust of a lander interacts with the surface ejecting large amounts of regolith particles at high velocities that can interfere with the landing, disturb the surface, and damage hardware. To better understand PSI, the particle impact event (PIE) sensor is being developed to measure the kinetic energy and the flux of ejecta during landings, to quantify the potential damage, and to quantify the ejecta displaced. Multiple parameters were estimated to define the PIE instrument requirements. These estimates demonstrate that ejecta can travel at velocities of up to 800 m/s and impact the surrounding area with energies of up to 400 µJ. A significant amount of ejecta can be deposited several 10 s of meters away from the landing site, modifying the surface and causing dust-related challenges. The PIE sensor will be launched for the first time in an upcoming lunar lander. Then, PIE measurements will be used to improve PSI prediction capabilities and develop mitigation strategies to ensure safe landings.
This report describes more than 5000 hours of successful 500 °C operation of semiconductor integrated circuits (ICs) with more than 100 transistors. Multiple packaged chips with two different 4H-SiC ...junction field effect transistor (JFET) technology demonstrator circuits have surpassed thousands of hours of oven-testing at 500 °C. After 100 hours of 500 °C burn-in, the circuits (except for 2 failures) exhibit less than 10% change in output characteristics for the remainder of 500 °C testing. We also describe the observation of important differences in IC materials durability when subjected to the first nine constituents of Venus-surface atmosphere at 9.4 MPa and 460 °C in comparison to what is observed for Earth-atmosphere oven testing at 500 °C.
Substantial expansion of the practical environmental envelope for integrated circuit (IC) operation offers important benefits to a variety of automotive, aerospace, deep-well drilling, and ...manufacturing applications 1. ICs that can reliably operate for long time periods (years) in a harsh environment without degradation or need of diagnostic/maintenance intervention enable the largest benefits compared to IC technologies requiring added shielding, cooling, remote-location, maintenance, or other overhead to perform beneficial system functions. The ability to "cold-start" at low temperature (T ≤ −55°C) and continuously function through "warm-up" to extreme temperature is also important to most applications. Fig. 1 illustrates the massive difference between a Venus lander mission that relies on sheltering electronics from the caustic 91-atmosphere pressure 460°C surface environment (600 kg lander that returns data for less than a day) compared to the mission possible with electronics that can function for long duration without need of environmental sheltering (20 kg lander that operates for 60 days) 2, 3.
Complex integrated circuit (IC) chips rely on more than one level of interconnect metallization for routing of electrical power and signals. This work reports the processing and testing of 4H-SiC ...junction field effect transistor (JFET) prototype IC’s with two levels of metal interconnect capable of prolonged operation at 500 °C. Packaged functional circuits including 3- and 11-stage ring oscillators, a 4-bit digital to analog converter, and a 4-bit address decoder and random access memory cell have been demonstrated at 500 °C. A 3-stage oscillator functioned for over 3000 hours at 500 °C in air ambient. Improved reproducibility remains to be accomplished.
Background: Electronic medical records (EMRs) and laboratory information systems (LISs) commonly utilize patient identifiers such as legal name, sex, medical record number, and date of birth. There ...have been recommendations from some EMR working groups (e.g., the World Professional Association for Transgender Health) to include preferred name, pronoun preference, assigned sex at birth, and gender identity in the EMR. These practices are currently uncommon in the United States. There has been little published on the potential impact of these changes on pathology and LISs. Methods: We review the available literature and guidelines on the use of preferred name and gender identity on pathology, including data on changes in laboratory testing following gender transition treatments. We also describe pathology and clinical laboratory challenges in the implementation of preferred name at our institution. Results: Preferred name, pronoun preference, and gender identity have the most immediate impact on the areas of pathology with direct patient contact such as phlebotomy and transfusion medicine, both in terms of interaction with patients and policies for patient identification. Gender identity affects the regulation and policies within transfusion medicine including blood donor risk assessment and eligibility. There are limited studies on the impact of gender transition treatments on laboratory tests, but multiple studies have demonstrated complex changes in chemistry and hematology tests. A broader challenge is that, even as EMRs add functionality, pathology computer systems (e.g., LIS, middleware, reference laboratory, and outreach interfaces) may not have functionality to store or display preferred name and gender identity. Conclusions: Implementation of preferred name, pronoun preference, and gender identity presents multiple challenges and opportunities for pathology.
A comprehensive gas chromatography/mass spectrometry qualitative urine drug screen demonstrated valproic acid metabolites, nicotine, gabapentin, benztropine, and a large peak of tramadol. A ...comprehensive gas chromatography/mass spectrometry qualitative urine drug screen demonstrated valproic acid metabolites, nicotine, gabapentin, benztropine, and a large peak of tramadol (Fig. 1). Seizure activity may have been prevented in our adult patient by the antiepileptic properties of her bipolar medications (valproic acid and gabapentin); the time course of her ingestion may explain her normal vital signs.
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