Effect of Thermal Treatment for Pd and PdSi Schottky Contacts on p-GaN

2006 ◽  
Vol 517 ◽  
pp. 242-246
Author(s):  
C.K. Tan ◽  
Azlan Abdul Aziz ◽  
F.K. Yam ◽  
C.W. Lim ◽  
Hassan Zainuriah ◽  
...  
Keyword(s):  
Thermal Treatment ◽  
Schottky Barrier ◽  
Leakage Current ◽  
Schottky Diode ◽  
Schottky Diodes ◽  
Schottky Contacts ◽  
Electrical Characteristics ◽  
Barrier Heights

Pd Schottky diode exhibited stable rectifying behavior up to 500°C for 35 minutes in sequential annealing; with the Schottky barrier heights (SBHs), ΦB (I-V) of 0.6-0.7eV with the leakage current (LC) of 20 A at -5V. With the same range of SBHs, PdSi diodes were stable up to 500°C for 5 minutes with the LC of 0.182mA at -5V. The electrical characteristics obtained in this study are also compared with those obtained for Pd and PdSi Schottky diodes on p-GaN.

High Temperature capable SiC Schottky diodes, based on buried grid design.

2014 ◽  
Vol 2014 (HITEC) ◽  
pp. 000058-000060
Author(s):  
Tomas Hjort ◽  
Adolf Schöner ◽  
Andy Zhang ◽  
Mietek Bakowski ◽  
Jang-Kwon Lim ◽  
...  
Keyword(s):  
High Temperature ◽  
Schottky Barrier ◽  
Leakage Current ◽  
Schottky Diode ◽  
Schottky Diodes ◽  
Electrical Characteristics ◽  
Schottky Barrier Diodes ◽  
Grid Design ◽  
High Temperature Operation

Electrical characteristics of 4H-SiC Schottky barrier diodes, based on buried grid design are presented. The diodes, rated to 1200V/10A and assembled into high temperature capable TO254 packages, have been tested and studied up to 250°C. Compared to conventional SiC Schottky diodes, Ascatron's buried grid SiC Schottky diode demonstrates several orders of magnitude reduced leakage current at high temperature operation.

Metallurgical and Electrical Characteristics of MoAlx Schottky Contacts to n-GaAs

1992 ◽  
Vol 260 ◽  
Author(s):  
T. S. Huang ◽  
J. G. Peng ◽  
C. C. Lin
Keyword(s):  
Thermal Processing ◽  
Annealing Temperature ◽  
Schottky Diodes ◽  
Schottky Contacts ◽  
Electrical Characteristics ◽  
Interfacial Stability ◽  
X Ray Diffraction ◽  
X Ray ◽  
Barrier Heights ◽  
Current Voltage

ABSTRACTThe interfacial stability, surface morphology and electrical characteristics of MoAlx contacts to n-GaAs have been investigated by using x-ray diffraction, scanning electron microscopy, sheet resistance and current-voltage measurements. The compositions of rf-cosputtered MoAlx films were x = 0.35, 2.7, and 7.0, respectively. The contacts were annealed by rapid thermal processing in the temperature range 500–1000 °C for 20 s. The interfaces of MoAl0.35/GaAs and MoAl2,7/GaAs were stable up to 900 °C, while the interfaces of MoAl7.0/GaAs were less stable and reactions occurred above 800 °C. The variations of sheet resistances and the barrier heights of the Schottky diodes as a function of annealing temperatures can be well correlated to the interfacial stability. The MoAl2.7/n-GaAs diodes exhibited the best stability and were characterized by the highest barrier height (0.98 V) and nearly unit ideality factor (1.11) after annealing at 900 °C. For all thermally stable MoAlx/n-GaAs Schottky diodes, the barrier heights increased with annealing temperature.

Electrical Characteristics of Schottky Contacts on Ge-Doped 4H-SiC

2014 ◽  
Vol 778-780 ◽  
pp. 706-709 ◽  
Author(s):  
Marilena Vivona ◽  
Kassem Al Assaad ◽  
Véronique Soulière ◽  
Filippo Giannazzo ◽  
Fabrizio Roccaforte ◽  
...  
Keyword(s):  
Schottky Barrier ◽  
Schottky Diodes ◽  
Sample Surface ◽  
Schottky Contacts ◽  
Electrical Characteristics ◽  
Conductive Atomic Force Microscopy ◽  
Near Surface ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After

We report on the electrical characteristics of Ni/4H-SiC Schottky contacts fabricated on a Ge-doped 4H-SiC epilayer. The morphology and the current mapping carried out by conductive atomic force microscopy on the epilayer allowed observing nanoscale preferential conductive paths on the sample surface. The electrical characteristics of Ni contacts have been studied before and after a rapid thermal annealing process. A highly inhomogeneous Schottky barrier was observed in as-deposited diodes, probably related to the surface electrical inhomogeneities of the 4H-SiC epilayer. A significant improvement of the Schottky diodes characteristics was achieved after annealing at 700°C, leading to the consumption of the near surface epilayer region by Ni/4H-SiC reaction. After this treatment, the temperature behavior of the ideality factor and Schottky barrier height was comparable to that observed on commercial 4H-SiC material.

Comparison of Electrical Characteristics of 4H-SiC(0001) and (000-1) Schottky Barrier Diodes

2006 ◽  
Vol 527-529 ◽  
pp. 927-930 ◽  
Author(s):  
Tomonori Nakamura ◽  
Toshiyuki Miyanagi ◽  
Isaho Kamata ◽  
Hidekazu Tsuchida
Keyword(s):  
Schottky Barrier ◽  
Annealing Temperature ◽  
Schottky Contact ◽  
Schottky Contacts ◽  
Electrical Characteristics ◽  
Schottky Barrier Diodes ◽  
Barrier Heights ◽  
Excess Current ◽  
Low Leakage ◽  
Low Leakage Current

We compared the electrical characteristics of 4H-SiC(0001) and (000-1) Schottky barrier diodes (SBDs), and derived the Schottky barrier heights (Hbs) of Ta, W, Mo, and Pd on {0001}. We investigated the annealing temperature dependence of Hbs in Mo and the W Schottky contacts for (0001) and (000-1). The Hbs are increased by annealing, except for the W Schottky contact on (0001). The yields of 0.25 cm2 as-deposited Mo-SBDs were 93.3% for (0001) and 71.1% for (000-1), respectively. We also demonstrated over 1 cm2 (0001) as-deposited Mo-SBD with a low leakage current, an excellent ideality factor, and no excess current, encouraging the enlargement of the active area in the SBD.

scholarly journals Reduction of reverse leakage current at the TiO2/GaN interface in field plate Ni/Au/n-GaN Schottky diodes

2021 ◽  
Vol 24 (04) ◽  
pp. 399-406
Author(s):  
A.M. Goriachko ◽  
◽  
M.V. Strikha ◽  
◽  
Keyword(s):  
Leakage Current ◽  
Schottky Diode ◽  
Schottky Diodes ◽  
Electrical Characteristics ◽  
Temperature Dependent ◽  
Field Plate ◽  
Reverse Leakage Current ◽  
Plate Length ◽  
Fabrication Procedure ◽  
Field Oxide

This paper presents the fabrication procedure of TiO2 passivated field plate Schottky diode and gives a comparison of Ni/Au/n-GaN Schottky barrier diodes without field plate and with field plate of varying diameters from 50 to 300 µm. The influence of field oxide (TiO2) on the leakage current of Ni/Au/n-GaN Schottky diode was investigated. This suggests that the TiO2 passivated structure reduces the reverse leakage current of Ni/Au/n-GaN Schottky diode. Also, the reverse leakage current of Ni/Au/n-GaN Schottky diodes decreases as the field plate length increases. The temperature-dependent electrical characteristics of TiO2 passivated field plate Ni/Au/n-GaN Schottky diodes have shown an increase of barrier height within the temperature range 300…475 K.

4H-SiC Trench Structure Schottky Diodes

2012 ◽  
Vol 717-720 ◽  
pp. 933-936 ◽  
Author(s):  
Masatoshi Aketa ◽  
Yuta Yokotsuji ◽  
Mineo Miura ◽  
Takashi Nakamura
Keyword(s):  
Schottky Barrier ◽  
Leakage Current ◽  
Voltage Drop ◽  
Schottky Diodes ◽  
The Novel ◽  
Barrier Heights ◽  
Switching Losses ◽  
Forward Voltage Drop ◽  
Key Issues ◽  
Trench Structure

This paper presents three different structures of Schottky diodes that were fabricated with low Schottky barrier heights. To reduce the forward voltage drop, the introduction of a lower Schttoky barrier is necessary. One of key issues associated with diodes having a low Schottky barrier height and a planar structure is an excessively high leakage current. By introducing the novel trench structure, the leakage current was reduced to a reasonable level. Furthermore it was confirmed that they have minimal switching time during turn-off and high avalanche capability. Thus trench structure Schottky diodes are able to reduce not only switching losses but also conductive losses and demonstrate sufficient robustness.

3.3 kV Rated Silicon Carbide Schottky Diodes with Epitaxial Field Stop Ring

2011 ◽  
Vol 679-680 ◽  
pp. 555-558 ◽  
Author(s):  
Konstantin Vassilevski ◽  
Irina P. Nikitina ◽  
Alton B. Horsfall ◽  
Nicolas G. Wright ◽  
C. Mark Johnson
Keyword(s):  
Silicon Carbide ◽  
Leakage Current ◽  
Schottky Diodes ◽  
Schottky Contacts ◽  
Blocking Layer ◽  
Donor Concentration ◽  
Ion Etching ◽  
Ambient Temperatures ◽  
Heavily Doped ◽  
The Impact

3.3 kV rated 4H-SiC diodes with nickel monosilicide Schottky contacts and 2-zone JTE regions were fabricated on commercial epitaxial wafers having a 34 m thick blocking layer with donor concentration of 2.2×1015 cm-3. The diodes were fabricated with and without additional field stop rings to investigate the impact of practically realizable stopper rings on the diode blocking characteristics. The field stop ring was formed by reactive ion etching of heavily doped epitaxial capping layer. The diodes with field stop rings demonstrated significantly higher yield and reduction of reverse leakage current. The diodes demonstrated blocking voltages in excess of 4.0 kV and very low change of leakage current at ambient temperatures up to 200 °C.

Phase Inhomogeneity and Electrical Characteristics of Nickel Silicide Schottky Contacts Formed on 4H-SiC

2009 ◽  
Vol 615-617 ◽  
pp. 577-580 ◽  
Author(s):  
Irina P. Nikitina ◽  
Konstantin Vassilevski ◽  
Alton B. Horsfall ◽  
Nicolas G. Wright ◽  
Anthony G. O'Neill ◽  
...  
Keyword(s):  
Nickel Silicide ◽  
Schottky Contacts ◽  
Electrical Characteristics ◽  
Adhesion Layer ◽  
Temperature Range ◽  
Barrier Heights ◽  
Phase Inhomogeneity ◽  
Layer 4 ◽  
State Chemical ◽  
Nisi Phase

Nickel silicide Schottky contacts were formed on 4H-SiC by consecutive deposition of a titanium adhesion layer, 4 nm thick, and nickel, 100 nm thick, followed by annealing at temperatures from 600 to 750 °C. It was found that contacts with barrier heights of 1.45 eV, consisting mainly of NiSi phase, formed in the 600-660 °C temperature range, while annealing at around 750 °C led to the formation of Ni2Si phase with barrier heights of 1.1 eV. Annealing at intermediate temperatures resulted in the nucleation of Ni2Si grains embedded in the NiSi film which were directly observed by micro-Raman mapping. It was concluded that the thermodynamically unfavourable NiSi phase appeared in the 600-660 °C temperature range due to the fact that the solid state chemical reaction between Ni and SiC at these temperatures is controlled by nickel diffusion through the titanium barrier.

Investigation of Stacking Faults Affecting on Reverse Leakage Current of 4H-SiC Junction Barrier Schottky Diodes Using Device Simulation

2014 ◽  
Vol 778-780 ◽  
pp. 828-831 ◽  
Author(s):  
Junichi Hasegawa ◽  
Kazuya Konishi ◽  
Yu Nakamura ◽  
Kenichi Ohtsuka ◽  
Shuhei Nakata ◽  
...  
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Leakage Current ◽  
Schottky Barrier Height ◽  
Schottky Diodes ◽  
Stacking Faults ◽  
Metal Electrode ◽  
Reverse Leakage Current ◽  
Electrode Interface ◽  
The Relationship

We clarified the relationship between the enhanced leakage current of SiC Junction Barrier Schottky diodes and the stacking faults in the SiC crystal at the SiC and metal electrode interface by measuring the electrical and optical properties, and confirm by using the numerical simulations. Numerical simulation considering local lowering of Schottky barrier height, which is 0.8 eV lower than that of 4H-SiC well explained the 2-4 orders of magnitude higher reverse leakage current caused by the SFs. We concluded that the locally lowering of the Schottky barrier height at the 3C-SiC layer in the 4H-SiC surface is a main cause of the large reverse leakage current.

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