Engineering topics

Fogarty, T. N.

Publications and source records attributed to Fogarty, T. N..

6 records

NASA NTRS1998

Verification and Quantification of Single Event Effects on High Speed SRAM in Terrestrial Environments

As integrated circuits become more sensitive to charged particles and neutrons, anomalous performance due to single event effects (SEE) is a concern and requires experimental verification and quantification. The Center for Applied Radiation Research (CARR) at Prairie View A&M University has developed experiments as a participant in the NASA ER-2 Flight Program, the APEX balloon flight program and the Student Launch Program. Other high altitude and ground level experiments of interest to DoD and commercial applications are being developed. The experiment characterizes the SEE behavior of high speed and high density SRAM's. The system includes a PC-104 computer unit, an optical drive for storage, a test board with the components under test, and a latchup detection and reset unit. The test program will continuously monitor the stored checkerboard data pattern in the SW and record errors. Since both the computer and the optical drive contain integrated circuits, they are also vulnerable to radiation effects. A latchup detection unit with discrete components will monitor the test program and reset the system when necessary. The first results will be obtained from the NASA ER-2 flights, which are now planned to take place in early 1998 from Dryden Research Center in California. The series of flights, at altitudes up to 70,000 feet, and a variety of flight profiles should yield a distribution of conditions for correlating SEES. SEE measurements will be performed from the time of aircraft power-up on the ground throughout the flight regime until systems power-off after landing.

Huff, H.↗

NASA NTRS1997

Process and Radiation Induced Defects in Electronic Materials and Devices

Process and radiation induced defects are characterized by a variety of electrical techniques, including capacitance-voltage measurements and charge pumping. Separation of defect type into stacking faults, displacement damage, oxide traps, interface states, etc. and their related causes are discussed. The defects are then related to effects on device parameters. Silicon MOS technology is emphasized. Several reviews of radiation effects and silicon processing exist.

Washington, Kenneth↗

NASA NTRS1994

Ilmenite as Dual-Use Material

This paper addresses the subject of dual-use space technology transfer of a novel, non-traditional material termed ilmenite, found in a large percentage in the moon rocks brought back by NASA's APOLLO missions. The paper is somewhat premature in the sense that though the material as a mineral has been known for a long time, very little is known about pure single crystal ilmenite and hence few applications have been demonstrated. Yet, in another sense, it is very timely due to the fact that ilmenite promises to be a very interesting competition to silicon, silicon carbide and other compound semiconductors, especially those that are employed in high power, high temperature and large data storage/retrieval applications. It seems to be an excellent example of a small investment-high return situation. While some of the applications of this material - for production of oxygen, for instance - have been well-known, electronic applications have received relatively little attention. One reason for this was the fact that growth of single crystal ilmenite requires precise process conditions and parameters. We believe for the first time these have been determined in the Center for Electronic Materials, Texas A&M University. The work being done at Texas A&M University and Prairie View A&M University (supported by Battelle Pacific Northwest Laboratories and the Center for Space Power) indicates the excellent potential this material has in space as well as in terrestrial applications. To mention a few: as a wide band gap semiconductor it has applications in high temperature, high power situations, especially when heat dissipation is a problem such as may occur in the Space Station; the possibility of this material radiating in the blue region, it has immense applications in optoelectronics; as a material with a high density of highly directional d-bands, it lends itself to novel processing conditions and perhaps even to 'tunability' of physical parameters; as a potential scintillating material, it has possible applications as a sensor in waste management; as an oxygen sensor it has possible applications in automotive electronics; and as a radiation resistant material, it has obvious applications in the space environment. Results - experimental and theoretical - obtained so far in our laboratories will be reported with particular emphasis on the transfer of technology involving this fascinating material.

Kumar, A. A.↗

NASA NTRS1993

Modeling and experimental verification of single event upsets

The research performed and the results obtained at the Laboratory for Radiation Studies, Prairie View A&M University and Texas A&I University, on the problem of Single Events Upsets, the various schemes employed to limit them and the effects they have on the reliability and fault tolerance at the systems level, such as robotic systems are reviewed.

Fogarty, T. N.↗

NASA NTRS1991

A nuclear fragmentation energy deposition model

A formalism for target fragment transport is presented with application to energy loss spectra in thin silicon devices. A nuclear data base is recommended that agrees well with the measurements of McNulty et al. using surface barrier detectors. High-energy events observed by McNulty et al., which are not predicted by intranuclear cascade models, are well represented by the present work.

NASA Discipline Number 04-10↗

NASA NTRS1989

Effects of cosmic rays on single event upsets

Assistance was provided to the Brookhaven Single Event Upset (SEU) Test Facility. Computer codes were developed for fragmentation and secondary radiation affecting Very Large Scale Integration (VLSI) in space. A computer controlled CV (HP4192) test was developed for Terman analysis. Also developed were high speed parametric tests which are independent of operator judgment and a charge pumping technique for measurement of D(sub it) (E). The X-ray secondary effects, and parametric degradation as a function of dose rate were simulated. The SPICE simulation of static RAMs with various resistor filters was tested.

Venable, D. D.↗