The semiconductor-dielectric interface from PN junction edge and the voltage dependence of leakage reverse current

The isothermal charging current and the isothermal discharging current in low mobility materials are analyzed either in terms of polarization mechanisms or in terms of charge injection/extraction at the metal-dielectric interface and the conduction current through the dielectric material. We propose to measure the open-circuit isothermal charging and discharging currents just to overpass the difficulties related to the analysis of the conduction mechanisms in dielectric materials. We demonstrate that besides a polarization current there is a current related to charge injection or extraction at the metal-dielectric interface and a reverse current related to the charge trapped into the shallow superficial or near superficial states of the dielectric and which can move at the interface in the opposite way that occurring during injection. Two important parameters can be determined (i) the highest value of the relaxation time for the polarization mechanisms which are involved into the transient current and (ii) the height of the potential barrier W0 at the metal-dielectric interface. The experimental data demonstrate that there is no threshold field for electron injection/extraction at a metal-dielectric interface.

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Formation of radiation-disturbed layer in Al/SiO2/n-Si structures irradiated by helium ions with energy 5 MeV

HUE UNIVERSITY JOURNAL OF SCIENCE NATURAL SCIENCE ◽

10.26459/hueuni-jns.v129i1d.5765 ◽

2020 ◽

Vol 129 (1D) ◽

Author(s):

Vo Quang Nha ◽

Le Vinh Thang ◽

Huynh Thi Thuy Linh ◽

Gorbachuk Nikolai Ivanovich ◽

Ngo Xuan Cuong

Keyword(s):

Frequency Dependence ◽

Voltage Dependence ◽

Charged Particles ◽

Reverse Current ◽

Helium Ions ◽

Continuous Radiation ◽

Disturbed Layer ◽

Agilent E4980a

This paper focuses on researching the change in the volt-farad characteristic of the Al/SiO2/n-Si structure irradiated by helium ions with the energy of 5 MeV in different frequencies of 1 kHz; 10 kHz; 100 kHz and 1 MHz. The voltage dependence of the capacitance and the frequency dependence of the dissolution angle are measured by LCR Agilent E4980A and Agilent 4285A meter. The complex electrical module’s hodograph of irradiated structure shows that there is a formation of quasi-continuous radiation-disturbed layer at fluence 1012 cm-2 with U < -7 V and at 1013 cm-2 with U < -20 V, which enhances the speed of charged particles, thereby increasing the reverse current in the irradiated structure.

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Experimental Investigation on the Leakage Reverse Current Component Flowing at the Semiconductor PN Junction Periphery

7th. Int. Conf. on Thermal, Mechanical and Multiphysics Simulation and Experiments in Micro-Electronics and Micro-Systems ◽

10.1109/esime.2006.1644014 ◽

2006 ◽

Cited By ~ 2

Author(s):

V.V.N. Obreja ◽

C. Codreanu

Keyword(s):

Experimental Investigation ◽

Reverse Current ◽

Current Component ◽

Pn Junction

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Variant of Excess Current in 4H-SiC pn Structures

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.859 ◽

2014 ◽

Vol 778-780 ◽

pp. 859-862 ◽

Cited By ~ 2

Author(s):

Anatoly M. Strel'chuk ◽

Evgenia V. Kalinina ◽

Alexander A. Lebedev ◽

Irina K. Boricheva ◽

Vladimir V. Pavshukov

Keyword(s):

Voltage Dependence ◽

Schottky Barriers ◽

Excess Current ◽

Pn Junction ◽

Current Voltage ◽

Carbon Coated ◽

Coated Surfaces

Excess currents and defects were investigated in the 4H-SiC p+nn+ structures created by implantation. It was found that the principal p+n junction is shunted by several or multiple Schottky barriers connected in parallel to the principal pn junction and formed by a contact of Al on the surface of p+-layer with n-layer perhaps with participation of carbon coated surfaces of the pits or other defects. Amount and area of Schottky barriers vary for different pn structures, in connection with which vary as the value of the excess current and character of the current-voltage dependence, and, apparently, that was observed in some cases, the instability of excess current.

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Breakdown Behavior of 900-V 4H-SiC Schottky Barrier Diodes Terminated with Boron-Implanted pn-Junction

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.955 ◽

2008 ◽

Vol 600-603 ◽

pp. 955-958

Author(s):

Pavel A. Ivanov ◽

Igor V. Grekhov

Keyword(s):

Schottky Barrier ◽

Breakdown Voltage ◽

Reverse Current ◽

Differential Resistance ◽

Avalanche Breakdown ◽

Schottky Barrier Diodes ◽

Boron Diffusion ◽

Reverse Voltage ◽

Pn Junction ◽

Pulse Reverse

High-voltage (900 V) 4H-SiC Schottky-barrier diodes (SBD) terminated with guard pnjunction were fabricated and investigated. The guard pn-junction was formed by room temperature boron implantation followed by high temperature annealing. Owing to the transient enhanced boron diffusion during anneal, the depth of guard pn-junction is about 1.7 μm, that is approximately 1 μm deeper than the expected average range of 11B ions in 4H-SiC. The maximum reverse voltage of 4H-SiC SBD produced has been found to be limited by the avalanche breakdown in cylindrical portion of planar pn-junction. The value of the breakdown voltage of 910 V is close to theoretical one calculated for the dopant density = 2.5×1015 cm-3, n-base thickness d = 12.5 μm and junction curvature rj = 1.7 μm. Dynamic (pulse) reverse current-voltage characteristics were measured in the breakdown regime. It was found that dynamic breakdown voltage increases with shortening the pulse duration. Due to homogeneous avalanche breakdown at the edge of the quard pn-junction and high differential resistance in the breakdown regime, the diodes under test are able to withstand, with no degradation, pulse reverse voltage at least 1600 V.

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