Engineering topics
Publications and source records attributed to Schwartz, H. R..
A fifth set of heavy ion single event effects (SEE) test data have been collected since the last IEEE publications (1,2,3,4) in December issues for 1985, 1987, 1989, and 1991. Trends in SEE susceptibility (including soft errors and latchup) for state-of-the-art parts are evaluated.
A seventh set of heavy ion single event effects (SEE) test data have been collected since the last IEEE publications. SEE trends are indicated for several functional classes of ICs.
This paper discusses single-event upset effets in flash memories, using heavy ions at the Texas A&M cyclotron. Initial results are presented for one manufacturer that compare uspet in the individual memory elemts with the more complex funtion failure modes that occur in the internal state machine and its control registers. This device is designed to function with either 5-V or 3.3-V power supply levels for read operations, but requires an additional 5 or 12-V power supply for write and erase operations.
This paper presents a display of heavy-ion and proton-induced single event transients for selected linear devices. The transient vital signs are serious; low LET threshold, high voltage amplitude and extended pulse duration (microsecs.).
The sixth set of heavy ion single event effects (SEE) test data have been collected since the last IEEE publications in December issues of IEEE - Nuclear Science Transactions for 1985, 1987, 1989, 1991, and the IEEE Workshop Record, 1993. Trends in SEE susceptibility (including soft errors and latchup) for state-of- are evaluated.
A picosec pulsed dye laser beam was at selected wavelengths successfully used to simulate heavy-ion single-event effects (SEEs) in negative channel NMOS DRAMs. A DRAM was used to develop the test technique because bit-mapping capability and previous heavy-ion upset data were available. The present analysis is the first to establish such a correlation between laser and heavy-ion data for devices, such as the NMOS DRAM, where charge collection is dominated by long-range diffusion, which is controlled by carrier density at remote distances from a depletion region. In the latter case, penetration depth is an important parameter and is included in the present analysis. A single-pulse picosecond dye laser beam (1.5 microns diameter) focused onto a single cell component can upset a single memory cell; clusters of memory cell upsets (multiple errors) were observed when the laser energy was increased above the threshold energy. The multiple errors were analyzed as a function of the bias voltage and total energy of a single pulse. A diffusion model to distinguish the multiple upsets from the laser-induced charge agreed well with previously reported heavy ion data.
JPL and the Aerospace Corporation have collected a fourth set of heavy ion single event effects (SEE) test data. Trends in SEE susceptibility (including soft errors and latchup) for state-of-the-art parts are displayed. All data are conveniently divided into two tables: one for MOS devices, and one for a shorter list of recently tested bipolar devices. In addition, a new table of data for latchup tests only (invariably CMOS processes) is given.
A 256K DRAM has been used to study the lateral transport of charge (electron-hole pairs) induced by direct ionization from heavy-ion tracks in an IC. The qualitative charge transport has been simulated using a two-dimensional numerical code in cylindrical coordinates. The experimental bit-map data clearly show the manifestation of lateral charge transport in the creation of adjacent multiple-bit errors from a single heavy-ion track. The heavy-ion data further demonstrate the occurrence of multiple-bit errors from single ion tracks with sufficient stopping power. The qualitative numerical simulation results suggest that electric-field-funnel-aided (drift) collection accounts for single error generated by an ion passing through a charge-collecting junction, while multiple errors from a single ion track are due to lateral diffusion of ion-generated charge.
Results are given of SEU measurements on 256K dynamic RAMs with on-chip error correction. They are claimed to be the first ever reported. A (12/8) Hamming error-correcting code was incorporated in the layout. Physical separation of the bits in each code word was used to guard against multiple bits being disrupted in any given word. Significant reduction in observed errors is reported.
Methods for manufacturing and producing fire protective intumescent coatings are described. The coatings consist of three reactive parts mixed together at the time of use. The chemical composition of the reactive parts is discussed. The characteristics of the coatings which are obtained by three types of processing are analyzed. Qualification tests of the materials to determine acceptability are reported.