Publications

Allerman, A.A.; Crawford, Mary H.; Pickrell, Gregory P.; Kaplar, Robert K.; Armstrong, Andrew A.; Dickerson, Jeramy R.; Klein, Brianna A.; King, Michael P.; Van Heukelom, Michael V.

Abstract not provided.

Celio, Kimberlee C.; Leonard, Francois L.; Dickerson, Jeramy R.; King, Michael P.; Crawford, Mary H.; Armstrong, Andrew A.; Allerman, A.A.; Aktas, Ozgur A.; Kizilyalli, Isik C.; Talin, A.A.

Abstract not provided.

Pickrell, Gregory P.; Allerman, A.A.; Crawford, Mary H.; Armstrong, Andrew A.; Dickerson, Jeramy R.; King, Michael P.; Cross, Karen C.; Glaser, Caleb E.; Van Heukelom, Michael V.; Kaplar, Robert K.

Abstract not provided.

Kaplar, Robert K.; Allerman, A.A.; Armstrong, Andrew A.; Crawford, Mary H.; Baca, A.G.; Flicker, Jack D.; Pickrell, Gregory P.; Dickerson, Jeramy R.; Klein, Brianna A.; Douglas, Erica A.; Miller, Mary A.; Leonard, Francois L.; Talin, A.A.; Celio, Kimberlee C.; Reza, Shahed R.; King, Michael P.; Vizkelethy, Gyorgy V.; Coltrin, Michael E.

Abstract not provided.

Dickerson, Jeramy R.; Crawford, Mary H.; Allerman, A.A.; King, Michael P.; Kaplar, Robert K.

Abstract not provided.

Armstrong, Andrew A.; Allerman, A.A.; Fischer, Arthur J.; King, Michael P.; Van Heukelom, Michael V.; Moseley, Michael; Kaplar, Robert K.; Wierer, J.Jr.; Crawford, Mary H.; Dickerson, Jeramy R.; Jayawardena, A.J.; Ahyi, A.A.; Dhar, S.D.

Abstract not provided.

Kaplar, Robert K.; Allerman, A.A.; Armstrong, Andrew A.; Crawford, Mary H.; Dickerson, Jeramy R.; Fischer, Arthur J.; Leonard, Francois L.; Talin, A.A.; King, Michael P.; Baca, A.G.; Douglas, Erica A.

Abstract not provided.

Kaplar, Robert K.; Allerman, A.A.; Armstrong, Andrew A.; Crawford, Mary H.; Dickerson, Jeramy R.; Fischer, Arthur J.; Leonard, Francois L.; Talin, A.A.; King, Michael P.; Baca, A.G.; Douglas, Erica A.

Abstract not provided.

Allerman, A.A.; Armstrong, Andrew A.; Baca, A.G.; Crawford, Mary H.; Dickerson, Jeramy R.; King, Michael P.; Fischer, Arthur J.; Kaplar, Robert K.; Douglas, Erica A.

Abstract not provided.

Allerman, A.A.; Crawford, Mary H.; Armstrong, Andrew A.; Baca, A.G.; Dickerson, Jeramy R.; King, Michael P.; Kaplar, Robert K.; Lee, Stephen R.

Abstract not provided.

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.

Abstract not provided.

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/Al_0.85Ga_0.15N 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 I_on/I_off 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.

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 Al0_0.3Ga_0.7N 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 (V_br²/R_spec,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.

King, Michael P.; Wu, X.Q.; Eller, M.E.; Samavedam, S.S.; Shaneyfelt, Marty R.; Silva, Antoinette I.; Draper, Bruce L.; Rice, William C.; Meisenheimer, Timothy L.; Zhang, E.Z.; Haeffner, T.D.; Ball, D.R.; Shetler, K.J.; Alles, M.L.; Kauppila, J.S.; Massengill, Lloyd W.

Abstract not provided.

Vizkelethy, Gyorgy V.; King, Michael P.; Atkas, O.A.; Kizilyalli, I.C.K.; Kaplar, Robert K.

Abstract not provided.

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

Abstract not provided.

King, Michael P.; Wu, K.W.; Draper, Bruce L.; Meisenheimer, Timothy L.; Zhang, E.Z.; Shetler, K.J.; Haeffner, T.D.; Massengill, Lloyd W.

Abstract not provided.

King, Michael P.; Wu, Kevin W.; Eller, M.E.; Samavedam, S.S.; Draper, Bruce L.; Meisenheimer, Timothy L.; Zhang, E.Z.; Shetler, K.J.; Haeffner, T.D.; Massengill, Lloyd W.

Abstract not provided.

Roche, N.J.; Khachatrian, A.K.; King, Michael P.; Buchner, S.P.; Kaplar, Robert K.; Armstrong, Andrew A.; Kizilyalli, I.C.; Cunningham, P.D.; Melinger, J.S.; McMorrow, D.M.

Abstract not provided.

Kaplar, Robert K.; Kizilyalli, Isik C.; Aktas, Ozgur A.; Armstrong, Andrew A.; King, Michael P.; Vizkelethy, Gyorgy V.; Wampler, William R.; Fleming, Robert M.; Dickerson, Jeramy R.; Leonard, Francois L.; Talin, A.A.; Celio, Kimberlee C.; Neely, Jason C.; Zutavern, Fred J.; Mauch, Daniel L.

Abstract not provided.

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.

Abstract not provided.

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.

Kaplar, Robert K.; Allerman, A.A.; Armstrong, Andrew A.; Fischer, Arthur J.; Crawford, Mary H.; Dickerson, Jeramy R.; King, Michael P.; Baca, A.G.; Neely, Jason C.

Abstract not provided.

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.

Paisley, Elizabeth A.; Brumbach, Michael T.; Shelton, Christopher T.; Rost, Christina R.; King, Michael P.; Kaplar, Robert K.; Atcitty, Stanley A.; Maria, Jon-Paul M.; Ihlefeld, Jon I.

Abstract not provided.