Publications

62 Results
Skip to search filters

Investigating Heavy-Ion Effects on 14-nm Process FinFETs: Displacement Damage Versus Total Ionizing Dose

IEEE Transactions on Nuclear Science

Esposito, Madeline G.; Manuel, Jack E.; Privat, Aymeric; Xiao, T.P.; Garland, Diana; Bielejec, Edward S.; Vizkelethy, Gyorgy V.; Dickerson, Jeramy R.; Brunhaver, John S.; Talin, A.A.; Ashby, David; King, Michael P.; Barnaby, Hugh; McLain, Michael L.; Marinella, Matthew J.

Bulk 14-nm FinFET technology was irradiated in a heavy-ion environment (42-MeV Si ions) to study the possibility of displacement damage (DD) in scaled technology devices, resulting in drive current degradation with increased cumulative fluence. These devices were also exposed to an electron beam, proton beam, and cobalt-60 source (gamma radiation) to further elucidate the physics of the device response. Annealing measurements show minimal to no 'rebound' in the ON-state current back to its initial high value; however, the OFF-state current 'rebound' was significant for gamma radiation environments. Low-temperature experiments of the heavy-ion-irradiated devices reveal increased defect concentration as the result for mobility degradation with increased fluence. Furthermore, the subthreshold slope (SS) temperature dependence uncovers a possible mechanism of increased defect bulk traps contributing to tunneling at low temperatures. Simulation work in Silvaco technology computer-aided design (TCAD) suggests that the increased OFF-state current is a total ionizing dose (TID) effect due to oxide traps in the shallow trench isolation (STI). The significant SS elongation and ON-state current degradation could only be produced when bulk traps in the channel were added. Heavy-ion irradiation on bulk 14-nm FinFETs was found to be a combination of TID and DD effects.

More Details

Comparison of Sensitive Volumes Associated with Ion-and Laser-Induced Charge Collection in an Epitaxial Silicon Diode

IEEE Transactions on Nuclear Science

King, Michael P.; Ryder, Kaitlyn L.; Ryder, Landen D.; Sternberg, Andrew S.; Kozub, John K.; Zhang, Enxia Z.; Khachatrian, Ani K.; Buchner, Steven P.; McMorrow, Dale M.; Hales, Joel M.; Zhao, Yuanfu Z.; Wang, Liang W.; Wang, Chuanmin W.; Weller, Robert W.; Schrimpf, Ronald D.; Weiss, Sharon M.; Reed, Robert R.; Black, Dolores A.

A sensitive volume is developed using pulsed laser-induced collected charge for two bias conditions in an epitaxial silicon diode. These sensitive volumes show good agreement with experimental two photon absorption laser-induced collected charge at a variety of focal positions and pulse energies. When compared to ion-induced collected charge, the laser-based sensitive volume over predicts the experimental collected charge at low bias and agrees at high bias. Here, a sensitive volume based on ion-induced collected charge adequately describes the ion experimental results at both biases. Differences in the amount of potential modulation explain the differences between the ion-and laser-based sensitive volumes at the lower bias. Truncation of potential modulation by the highly doped substrate at the higher bias results in similar sensitive volumes.

More Details

Correlation of Sensitive Volumes Associated with Ion- and Laser-Induced Charge Collection in an Epitaxial Silicon Diode

Ryder, Kaitlyn L.; Ryder, Landen D.; Sternberg, Andrew S.; Kozub, John K.; Zhang, Enxia Z.; Khachatrian, Ani K.; Buchner, Steven P.; McMorrow, Dale M.; Hales, Joel M.; Zhao, Yuanfu Z.; Wang, Liang W.; Wang, Chuanmin W.; Weller, Robert W.; Schrimpf, Ronald D.; Weiss, Sharon M.; Reed, Robert R.; Black, Dolores B.; King, Michael P.

Abstract not provided.

Single-Event Characterization of 16 nm FinFET Xilinx UltraScale+ Devices with Heavy Ion and Neutron Irradiation

2018 IEEE Nuclear and Space Radiation Effects Conference, NSREC 2018

Lee, David S.; King, Michael P.; Evans, William L.; Cannon, Matthew; Perez-Celis, Andres; Anderson, Jordan; Wirthlin, Michael; Rice, William C.

This study examines the single-event response of Xilinx 16nm FinFET UltraScale+ FPGA and MPSoC device families. Heavy-ion single-event latch-up, single-event upsets in configuration SRAM, BlockRAM™ memories, and flip-flops, and neutron-induced single-event latch-up results are provided.

More Details

Ultrafast reverse recovery time measurement for wide-bandgap diodes

IEEE Transactions on Power Electronics

Mauch, Daniel L.; Zutavern, Fred J.; Delhotal, Jarod J.; King, Michael P.; Neely, Jason C.; Kizilyalli, Isik C.; Kaplar, Robert K.

A system is presented that is capable of measuring subnanosecond reverse recovery times of diodes in wide-bandgap materials over a wide range of forward biases (0 - 1 A) and reverse voltages (0 - 10 kV). The system utilizes the step recovery technique and comprises a cable pulser based on a silicon (Si) Photoconductive Semiconductor Switch (PCSS) triggered with an Ultrashort Pulse Laser, a pulse charging circuit, a diode biasing circuit, and resistive and capacitive voltage monitors. The PCSS-based cable pulser transmits a 130 ps rise time pulse down a transmission line to a capacitively coupled diode, which acts as the terminating element of the transmission line. The temporal nature of the pulse reflected by the diode provides the reverse recovery characteristics of the diode, measured with a high bandwidth capacitive probe integrated into the cable pulser. This system was used to measure the reverse recovery times (including the creation and charging of the depletion region) for two Avogy gallium nitride diodes; the initial reverse recovery time was found to be 4 ns and varied minimally over reverse biases of 50-100 V and forward current of 1-100 mA.

More Details

An AlN/Al0.85Ga0.15N high electron mobility transistor

Applied Physics Letters

Baca, A.G.; Armstrong, Andrew A.; Allerman, A.A.; Douglas, Erica A.; Sanchez, Carlos A.; King, Michael P.; Coltrin, Michael E.; Fortune, Torben R.; Kaplar, Robert K.

An AlN barrier high electron mobility transistor (HEMT) based on the AlN/Al0.85Ga0.15N heterostructure was grown, fabricated, and electrically characterized, thereby extending the range of Al composition and bandgap for AlGaN channel HEMTs. An etch and regrowth procedure was implemented for source and drain contact formation. A breakdown voltage of 810 V was achieved without a gate insulator or field plate. Excellent gate leakage characteristics enabled a high Ion/Ioff current ratio greater than 107 and an excellent subthreshold slope of 75 mV/decade. A large Schottky barrier height of 1.74 eV contributed to these results. In conclusion, the room temperature voltage-dependent 3-terminal off-state drain current was adequately modeled with Frenkel-Poole emission.

More Details

Al00.3Ga0.7N PN diode with breakdown voltage >1600 V

Electronics Letters

Allerman, A.A.; Armstrong, Andrew A.; Fischer, Arthur J.; Dickerson, Jeramy R.; Crawford, Mary H.; King, Michael P.; Moseley, Michael; Wierer, J.Jr.; Kaplar, Robert K.

Demonstration of Al00.3Ga0.7N PN diodes grown with breakdown voltages in excess of 1600 V is reported. The total epilayer thickness is 9.1 μm and was grown by metal-organic vapour-phase epitaxy on 1.3-mm-thick sapphire in order to achieve crack-free structures. A junction termination edge structure was employed to control the lateral electric fields. A current density of 3.5 kA/cm2 was achieved under DC forward bias and a reverse leakage current <3 nA was measured for voltages <1200 V. The differential on-resistance of 16 mΩ cm2 is limited by the lateral conductivity of the n-type contact layer required by the front-surface contact geometry of the device. An effective critical electric field of 5.9 MV/cm was determined from the epilayer properties and the reverse current–voltage characteristics. To our knowledge, this is the first aluminium gallium nitride (AlGaN)-based PN diode exhibiting a breakdown voltage in excess of 1 kV. Finally, we note that a Baliga figure of merit (Vbr2/Rspec,on) of 150 MW/cm2 found is the highest reported for an AlGaN PN diode and illustrates the potential of larger-bandgap AlGaN alloys for high-voltage devices.

More Details

Ultra-Wide-Bandgap Semiconductors for Generation-After-Next Power Electronics

Kaplar, Robert K.; Allerman, A.A.; Armstrong, Andrew A.; Crawford, Mary H.; Fischer, Arthur J.; Dickerson, Jeramy R.; King, Michael P.; Baca, A.G.; Douglas, Erica A.; Sanchez, Carlos A.; Neely, Jason C.; Flicker, Jack D.; Zutavern, Fred J.; Mauch, Daniel L.; Brocato, Robert W.; Rashkin, Lee; Delhotal, Jarod J.; Fang, Lu F.; Kizilyalli, Isik C.; Aktas, Ozgur A.

Abstract not provided.

Vertical GaN power diodes with a bilayer edge termination

IEEE Transactions on Electron Devices

Dickerson, Jeramy R.; Allerman, A.A.; Bryant, Benjamin N.; Fischer, Arthur J.; King, Michael P.; Moseley, Michael; Armstrong, Andrew A.; Kaplar, Robert K.; Kizilyalli, Isik C.; Aktas, Ozgur; Wierer, Jonathan J.

Vertical GaN power diodes with a bilayer edge termination (ET) are demonstrated. The GaN p-n junction is formed on a low threading dislocation defect density (104 - 105 cm-2) GaN substrate, and has a 15-μm-thick n-type drift layer with a free carrier concentration of 5 × 1015 cm-3. The ET structure is formed by N implantation into the p+-GaN epilayer just outside the p-type contact to create compensating defects. The implant defect profile may be approximated by a bilayer structure consisting of a fully compensated layer near the surface, followed by a 90% compensated (p) layer near the n-type drift region. These devices exhibit avalanche breakdown as high as 2.6 kV at room temperature. Simulations show that the ET created by implantation is an effective way to laterally distribute the electric field over a large area. This increases the voltage at which impact ionization occurs and leads to the observed higher breakdown voltages.

More Details

Effects of Stopping Ions and LET Fluctuations on Soft Error Rate Prediction

IEEE Transactions on Nuclear Science

Weeden-Wright, S.L.; King, Michael P.; Hooten, N.C.; Bennett, W.G.; Sierawski, B.D.; Schrimpf, R.D.; Weller, R.A.; Reed, R.A.; Mendenhall, M.H.; Fleetwood, D.M.; Alles, M.L.; Baumann, R.C.

Variability in energy deposition from stopping ions and LET fluctuations is quantified for specific radiation environments. When compared to predictions using average LET via CREME96, LET fluctuations lead to an order-of-magnitude difference in effective flux and a nearly 4x decrease in predicted soft error rate (SER) in an example calculation performed on a commercial 65 nm SRAM. The large LET fluctuations reported here will be even greater for the smaller sensitive volumes that are characteristic of highly scaled technologies. End-of-range effects of stopping ions do not lead to significant inaccuracies in radiation environments with low solar activity unless the sensitivevolume thickness is 100 μm or greater. In contrast, end-of-range effects for stopping ions lead to significant inaccuracies for sensitive- volume thicknesses less than 10 μm in radiation environments with high solar activity.

More Details
62 Results
62 Results