TY - JOUR

T1 - Negative Differential Resistance Observation and a New Fitting Model for Electron Drift Velocity in GaN-Based Heterostructures

AU - Atmaca, Gokhan

AU - Narin, Polat

AU - Kutlu, Ece

AU - Malin, Timur Valerevich

AU - Mansurov, Vladimir G.

AU - Zhuravlev, Konstantin Sergeevich

AU - Lisesivdin, Sefer Bora

AU - Ozbay, Ekmel

N1 - Funding Information: Manuscript received September 3, 2017; revised November 24, 2017 and December 26, 2017; accepted January 15, 2018. Date of publication February 8, 2018; date of current version February 22, 2018. This work was supported in part by the International Bilateral Research Project between RFBR and TUBITAK under Project 113F364, in part by the Projects DPT-HAMIT, DPT-FOTON, NATO-SET-193, and TUBITAK through the Nanotechnology Research Center, Bilkent University, Turkey under Project 113E331, Project 109A015, and Project 109E301, in part by the Distinguished Young Scientist Award of Turkish Academy of Sciences (TUBA-GEBIP 2016), and in part by the Ministry of Education and Science of the Russian Federation with the unique identifier of the project RFMEFI57717X0250. The work of E. Özbay was supported by the Turkish Academy of Sciences. The review of this paper was arranged by Editor K. Kalna. (Corresponding author: Gökhan Atmaca.) G. Atmaca, P. Narin, E. Kutlu, and S. B. Lis¸esivdin are with the Lisesivdin Research Group, Faculty of Science, Department of Physics, Gazi University, 06500 Ankara, Turkey (e-mail: gokhanatmaca@ kuark.org). Publisher Copyright: © 1963-2012 IEEE.

PY - 2018/3

Y1 - 2018/3

N2 - The aim of this paper is an investigation of electric field-dependent drift velocity characteristics for Al0.3Ga0.7N/AlN/GaN heterostructures without and with in situ Si3N4 passivation. The nanosecond-pulsed current-voltage ( {I}-{V} ) measurements were performed using a 20-ns applied pulse. Electron drift velocity depending on the electric field was obtained from the {I}-{V} measurements. These measurements show that a reduction in peak electron velocity from \text {2.01} \times \text {10}^{\text {7}} to \text {1.39} \times \text {10}^{\text {7}} cm/s after in situ Si3N4 passivation. Also, negative differential resistance regime was observed which begins at lower fields with the implementation of in situ Si3N4 passivation. In our samples, the electric field dependence of drift velocity was measured over 400 kV/cm due to smaller sample lengths. Then, a well-known fitting model was fitted to our experimental results. This fitting model was improved in order to provide an adequate description of the field dependence of drift velocity. It gives reasonable agreement with the experimental drift velocity data up to 475 kV/cm of the electric field and could be used in the device simulators.

AB - The aim of this paper is an investigation of electric field-dependent drift velocity characteristics for Al0.3Ga0.7N/AlN/GaN heterostructures without and with in situ Si3N4 passivation. The nanosecond-pulsed current-voltage ( {I}-{V} ) measurements were performed using a 20-ns applied pulse. Electron drift velocity depending on the electric field was obtained from the {I}-{V} measurements. These measurements show that a reduction in peak electron velocity from \text {2.01} \times \text {10}^{\text {7}} to \text {1.39} \times \text {10}^{\text {7}} cm/s after in situ Si3N4 passivation. Also, negative differential resistance regime was observed which begins at lower fields with the implementation of in situ Si3N4 passivation. In our samples, the electric field dependence of drift velocity was measured over 400 kV/cm due to smaller sample lengths. Then, a well-known fitting model was fitted to our experimental results. This fitting model was improved in order to provide an adequate description of the field dependence of drift velocity. It gives reasonable agreement with the experimental drift velocity data up to 475 kV/cm of the electric field and could be used in the device simulators.

KW - 2-dimensional electron gas (2DEG)

KW - AlGaN

KW - drift velocity

KW - gallium nitride (GaN)

KW - negative differential resistivity (NDR)

KW - SiN passivation

UR - http://www.scopus.com/inward/record.url?scp=85041827103&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/1c081956-b469-34c8-8486-40b5b98fafbc/

U2 - 10.1109/TED.2018.2796501

DO - 10.1109/TED.2018.2796501

M3 - Article

AN - SCOPUS:85041827103

VL - 65

SP - 950

EP - 956

JO - IEEE Transactions on Electron Devices

JF - IEEE Transactions on Electron Devices

SN - 0018-9383

IS - 3

ER -