Characterization of the Al/RuO2 Interface Upon Thermal Annealing

1990 ◽  
Vol 181 ◽  
Author(s):  
Quat T. Vu ◽  
E. Kolawa ◽  
M-A. Nicolet
Keyword(s):  
Contact Resistance ◽  
Annealing Temperature ◽  
Electrical Measurement ◽  
Specific Contact Resistance ◽  
Annealing Duration ◽  
Type Model ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Specific Contact

ABSTRACTWe have characterized the Al/RuO2 interface after annealing at temperatures in the range 450° C-550° C for durations up to several hours by backscattering spectrometry, cross-sectional transmission electron microscopy, and electrical four point probe measurement of specially designed structures. The electrical measurement yields the specific contact resistance of the interface by applying a transmission line type model developped for this purpose. An interfacial aluminum-oxygen polycrystalline compound is shown to grow with annealing temperature and duration, with a concurrent reduction of a thin layer of RuO2. However, the specific contact resistance between Al and RuO2 is found to decrease with annealing duration at 500°C. This last result indicates that the interfacial reaction does not lead to an insulating interface as could have been expected if the growth were pure and dense A12O3.

Improvement of the Specific Contact Resistance on P-Type 4H-SiC by Using a Highly P-Typed Doped 4H-SiC Layer Selectively Grown by VLS Transport

2014 ◽  
Vol 806 ◽  
pp. 57-60
Author(s):  
Nicolas Thierry-Jebali ◽  
Arthur Vo-Ha ◽  
Davy Carole ◽  
Mihai Lazar ◽  
Gabriel Ferro ◽  
...  
Keyword(s):  
Contact Resistance ◽  
Ohmic Contacts ◽  
Schottky Barrier Height ◽  
Annealing Temperature ◽  
Process Condition ◽  
Specific Contact Resistance ◽  
High Doping Level ◽  
Annealing Temperatures ◽  
Specific Contact ◽  
P Type

This work reports on the improvement of ohmic contacts made on heavily p-type doped 4H-SiC epitaxial layer selectively grown by Vapor-Liquid-Solid (VLS) transport. Even before any annealing process, the contact is ohmic. This behavior can be explained by the high doping level of the VLS layer (Al concentration > 1020 cm-3) as characterized by SIMS profiling. Upon variation of annealing temperatures, a minimum value of the Specific Contact Resistance (SCR) down to 1.3x10-6 Ω.cm2 has been obtained for both 500 °C and 800 °C annealing temperature. However, a large variation of the SCR was observed for a same process condition. This variation is mainly attributed to a variation of the Schottky Barrier Height.

Effect of Au distribution in NiO/Au film on the ohmic contact formation to p-type GaN

2005 ◽  
Vol 20 (2) ◽  
pp. 456-463 ◽  
Author(s):  
Jiin-Long Yang ◽  
J.S. Chen ◽  
S.J. Chang
Keyword(s):  
Electron Microscopy ◽  
Ohmic Contact ◽  
Incident Angle ◽  
Specific Contact Resistance ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
Ohmic Behavior ◽  
Transmission Electron ◽  
Specific Contact ◽  
P Type

The distribution of Au and NiO in NiO/Au ohmic contact on p-type GaN was investigated in this work. Au (5 nm) films were deposited on p-GaN substrates by magnetron sputtering. Some of the Au films were preheated in N2 ambient to agglomerate into semi-connected structure (abbreviated by agg-Au); others were not preheated and remained the continuous (abbreviated by cont-Au). A NiO film (5 nm) was deposited on both types of samples, and all samples were subsequently annealed in N2 ambient at the temperatures ranging from 100 to 500 °C. The surface morphology, phases, and cross-sectional microstructure were investigated by scanning electron microscopy, glancing incident angle x-ray diffraction, and transmission electron microscopy. I-V measurement on the contacts indicates that only the 400 °C annealed NiO/cont-Au/p-GaN sample exhibits ohmic behavior and its specific contact resistance (ρc) is 8.93 × 10−3 Ω cm2. After annealing, Au and NiO contact to GaN individually in the NiO/agg-Au/p-GaN system while the Au and NiO layers become tangled in the NiO/cont-Au/p-GaN system. As a result, the highly tangled NiO-Au structure shall be the key to achieve the ohmic behavior for NiO/cont-Au/p-GaN system.

scholarly journals Behavior of W and WSix Contact Metallization on n- and p- Type GaN

1999 ◽  
Vol 4 (S1) ◽  
pp. 684-690
Author(s):  
X. A. Cao ◽  
F. Ren ◽  
J. R. Lothian ◽  
S. J. Pearton ◽  
C. R. Abernathy ◽  
...  
Keyword(s):  
Contact Resistance ◽  
Annealing Temperature ◽  
Specific Contact Resistance ◽  
Ohmic Behavior ◽  
Contact Metallization ◽  
Specific Contact ◽  
Heavily Doped ◽  
Sputter Deposited ◽  
Optimum Annealing Temperature ◽  
P Type

Sputter-deposited W-based contacts on p-GaN (NA∼1018 cm−3) display non-ohmic behavior independent of annealing temperature when measured at 25°C. The transition to ohmic behavior occurs above ∼250°C as more of the acceptors become ionized. The optimum annealing temperature is ∼700°C under these conditions. These contacts are much more thermally stable than the conventional Ni/Au metallization, which shows a severely degraded morphology even at 700°C. W-based contacts may be ohmic as-deposited on very heavily doped n-GaN, and the specific contact resistance improves with annealing up to ∼900°C.

scholarly journals Ohmic contacts to Si-implanted and un-implanted n-type GaN

1995 ◽  
Vol 395 ◽  
Author(s):  
J. Brown ◽  
J Ramer ◽  
K. ZHeng ◽  
L.F. Lester ◽  
S.D. Hersee ◽  
...  
Keyword(s):  
Contact Resistance ◽  
Ohmic Contacts ◽  
Annealing Temperature ◽  
Contact Resistivity ◽  
Contact Structures ◽  
Specific Contact Resistance ◽  
Resistance Variation ◽  
Specific Contact ◽  
Metal Layers ◽  
Nitrogen Vacancies

ABSTRACTWe report on ohmic contacts to Si-implanted and un-implanted n-type GaN on sapphire. A ring shaped contact design avoids the need to isolate the contact structures by additional implantation or etching. Metal layers of Al and Ti/Al were investigated. On un-implanted GaN, post metalization annealing was performed in an RTA for 30 seconds in N2 at temperatures of 700, 800, and 900°C, A minimum specific contact resistance (rc) of 1.4×10−5 Ω-cm2 was measured for Ti/Al at an annealing temperature of 800°C. Although these values are reasonably low, variations of 95% in specific contact resistance were measured within a 500 µm distance on the wafer. These results are most likely caused by the presence of compensating hydrogen. Specific contact resistance variation was reduced from 95% to 10% by annealing at 900°C prior to metalization. On Si-implanted GaN, un-annealed ohmic contacts were formed with Ti/Al metalization. The implant activation anneal of 1120°C generates nitrogen vacancies that leave the surface heavily n-type, which makes un-annealed ohmic contacts with low contact resistivity possible.

Electrical & Structural Properties of TiSi2 Films

1988 ◽  
Vol 116 ◽  
Author(s):  
N.M. Ravindra ◽  
T. Fink ◽  
R.P. Moerkirk ◽  
D. Fathy
Keyword(s):  
Contact Resistance ◽  
Structural Properties ◽  
Specific Contact Resistance ◽  
Electrical Measurements ◽  
Temperature Dependent ◽  
Measurement Temperature ◽  
Transmission Electron ◽  
Device Structures ◽  
Specific Contact ◽  
Ti Films

AbstractStudies of the electrical and structural properties of TiSi2 films formed during the fabrication of shallow junctions by ion implanting As+ into p–Si through Ti films are reported here. Electrical measurements of the temperature dependent specific contact resistance and structural measurements such as transmission electron microscopy have been performed on these device structures. The specific contact resistance is seen to decrease with increasing measurement temperature. These studies have been carried out on furnace and rapid thermally annealed films.

scholarly journals Behavior of W and WSix Contact Metallization on n- and p- Type GaN

1998 ◽  
Vol 537 ◽  
Author(s):  
X. A. Cao ◽  
F. Ren ◽  
J. R. Lothian ◽  
S. J. Pearton ◽  
C. R. Abernathy ◽  
...  
Keyword(s):  
Contact Resistance ◽  
Annealing Temperature ◽  
Specific Contact Resistance ◽  
Ohmic Behavior ◽  
Contact Metallization ◽  
Specific Contact ◽  
Heavily Doped ◽  
Sputter Deposited ◽  
Optimum Annealing Temperature ◽  
P Type

AbstractSputter-deposited W-based contacts on p-GaN (NA∼1018cm-3) display non-ohmic behavior independent of annealing temperature when measured at 25°C. The transition to ohmic behavior occurs above ∼250°C as more of the acceptors become ionized. The optimum annealing temperature is ∼700°C under these conditions. These contacts are much more thermally stable than the conventional Ni/Au metallization, which shows a severely degraded morphology even at 700°C. W-based contacts may be ohmic as-deposited on very heavily doped n-GaN, and the specific contact resistance improves with annealing up to ∼900°C.

Nano-Electro-Structural Evolution of Ni-Si Ohmic Contacts to 3C-SiC

2009 ◽  
Vol 615-617 ◽  
pp. 569-572
Author(s):  
Jens Eriksson ◽  
Fabrizio Roccaforte ◽  
Filippo Giannazzo ◽  
Raffaella Lo Nigro ◽  
Giuseppe Moschetti ◽  
...  
Keyword(s):  
Ohmic Contacts ◽  
Annealing Temperature ◽  
Structural Evolution ◽  
Electrical Characterization ◽  
Nickel Silicide ◽  
Specific Contact Resistance ◽  
Specific Contact ◽  
Nanoscale Measurements

This paper reports on the macro- and nanoscale electro-structural evolution, as a function of annealing temperature, of nickel-silicide Ohmic contacts to 3C-SiC, grown on 6H-SiC substrates by a Vapor-Liquid-Solid (VLS) technique. The structural and electrical characterization of the contacts, carried out by combining different techniques, showed a correlation between the annealing temperature and the electrical characteristics in both the macro- and the nanoscale measurements. Increasing the annealing temperature between 600 and 950 °C caused a gradual increase of the uniformity of the nanoscale current-distribution, with an accompanying reduction of the specific contact resistance from 5 x 10-5 to 8.4 x 10-6 Ωcm2. After high temperature annealing (950 °C) the structural composition of the contacts stabilized, as only the Ni2Si phase was detected. A comparison with previous literature findings suggests a superior crystalline quality of the single domain VLS 3C-SiC layers.

Electrical Properties of (Zn, Mn) Containing Multilayer Metallizations to p-Type InGaAs/InP

1995 ◽  
Vol 382 ◽  
Author(s):  
Patrick W. Leec ◽  
Geoffrey K. Reeves ◽  
Wei Zhou
Keyword(s):  
Electrical Properties ◽  
Contact Resistance ◽  
Layer Thickness ◽  
Annealing Temperature ◽  
Specific Contact Resistance ◽  
Annealing Temperatures ◽  
Specific Contact ◽  
A Minor ◽  
P Type ◽  
Metal Layers

ABSTRACTThe specific contact resistance, pc, of Au/Zn/Au, Ni/Zn/Ni/Au, Pd/Zn/Pt/Au and Pd/Mln/Sb/Pd/Au contacts to p-In0.47Ga0.53As/ InP has been measured as a function of layer thickness of Zn or Mn. All of the as-deposited contacts were ohmic, with pc = 1−2 × 10−5 Ω cm2. Increasing thickness of the Zn layer above 200 Å in the Au/Zn/Au contacts resulted in a minor decrease in pc while producing no change in the Ni/Zn/Ni/Au metallization. For the as-deposited Pd/Mn/Pd/Au contacts, the value of pc was independent of thickness of the Mn layer but differences in pc emerged at annealing temperatures of ≥ 250°. The analysis of these structures by RBS has shown an extensive intermixing of the metal layers at an annealing temperature of 450 °. In the Pd/Zn/Pt/Au contacts, the value of pc was reduced to a minimum value of 8 × 10−6 Ω cm2 by annealing at a temperature of 500 °. An examination of the Pd/Zn/Pt/Au configuration by RBS has shown that the Pt layer acted as a barrier for the indiffusion of the Au.

Growth and Characterization of Epitaxial CoSi2-Contacts

1990 ◽  
Vol 181 ◽  
Author(s):  
C. Adamski ◽  
S. Meiser ◽  
D. Uffmann ◽  
L. Niewöhner ◽  
C. Schäffer
Keyword(s):  
Contact Resistance ◽  
Specific Contact Resistance ◽  
Dopant Distribution ◽  
Silicide Formation ◽  
Specific Contact ◽  
Ion Implanted

ABSTRACTThe growth of epitaxial CoSi2 by means of SPE on heavily ion implanted Si(111) was investigated with LEED, RBS and TEM. After silicide formation, the dopant distribution in silicide and silicon was determined by means of SIMS. In a self-aligned process epitaxial CoSi2/Si p+ contacts have been produced. The specific contact resistance was found to be lower than for polycrystalline CoSi2 contacts.

Pd/Ge Contacts to n-TYPE InP

1993 ◽  
Vol 300 ◽  
Author(s):  
Ping Jian ◽  
Douglas G. Ivey ◽  
Robert Bruce ◽  
Gordon Knight
Keyword(s):  
Contact Resistance ◽  
Amorphous Phase ◽  
Surface Region ◽  
Electron Beam Evaporation ◽  
Phase Changes ◽  
Specific Contact Resistance ◽  
Transmission Electron ◽  
Specific Contact ◽  
Different Thickness ◽  
Inp Surface

ABSTRACTMultilayer metallizations of Pd/Ge/Pd, with different thickness ratios of Ge and Pd, were deposited onto n-type InP by means of electron beam evaporation. The specimens were then annealed in flowing N2 gas at temperatures ranging from 250 to 425°C for various times. Transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDX) and electron diffraction were used to identify the phase changes during reaction. The four point probe method was used for electrical resistance measurements. A Pd-In-P amorphous phase and a Pd2Ge compound formed during deposition. Subsequent annealing resulted in crystallization of the amorphous phase followed by epitaxial growth of Pd2InP(II) on InP at 350°C. At 425°C, Pd2InP(II) with Ge in solution, decomposed producing a contact with a lower specific contact resistance. The lowest contact resistances achieved were ∼10−5 Ωcm2. Further annealing led to more decomposition of InP, including presumably the Ge doped InP surface region, which corresponded to an increase in contact resistance.

Sign in / Sign up

Export Citation Format

Share Document