Electrical Properties of Epitaxial Silicide-Silicon Interfaces

ABSTRACTThe Schottky barrier heights of single crystal NiSi2 layers on Si(111) have been studied by current-voltage, capacitance-voltage and activation energy techniques. Near ideal behavior is found for Schottky barriers grown on substrates cleaned at ∼820°C in ultrahigh vacuum. The Fermi level positions at the interfaces of single crystal type A and type B NiSi2 are shown to differ by ∼0.14 eV. Transmission electron microscopy demonstrated the epitaxial perfection of these suicide layers. At a cleaning temperature of 1050° C, the near surface region of lightly doped n-type Si was converted to p-type. The presence of a p-n junction was directly revealed by spreading resistance measurements and resulted in a high apparent Schottky barrier height (≥0.75 eV) which no longer bears immediate relationship to the interface Fermi level position.

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Effect of N2 Plasma Treatments on Dry Etch Damage in n- and p-type GaN

MRS Proceedings ◽

10.1557/proc-639-g3.16 ◽

2000 ◽

Vol 639 ◽

Author(s):

D.G. Kent ◽

K.P. Lee ◽

A.P. Zhang ◽

B. Luo ◽

M.E. Overberg ◽

...

Keyword(s):

Plasma Treatment ◽

Schottky Diodes ◽

Surface Region ◽

Chemical Effect ◽

Near Surface ◽

Current Voltage ◽

Extent Of Damage ◽

P Type ◽

Dry Etch ◽

N2 Plasma

ABSTRACTThe extent of damage recovery by N2 plasma treatment of previously damaged n- and p-GaN has been examined using current-voltage (I-V) characteristics from Schottky diodes. There are two contributions to the observed improvement in the I-V characteristics, namely a simple annealing effect and also a chemical effect from reactive nitrogen. However the N2 plasma treatment does not fully restore the initial electrical properties of the near-surface region.

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Schottky Barrier Height Dependence on the Metal Work Function for p-type Si Schottky Diodes

Zeitschrift für Naturforschung A ◽

10.1515/zna-2004-1112 ◽

2004 ◽

Vol 59 (11) ◽

pp. 795-798 ◽

Cited By ~ 9

Author(s):

Güven Çankaya ◽

Nazım Uçar

Keyword(s):

Fermi Level ◽

Schottky Barrier ◽

Schottky Diodes ◽

Metal Work Function ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Work Functions ◽

P Type ◽

Relationship Of ◽

Metal Work

We investigated Schottky barrier diodes of 9 metals (Mn, Cd, Al, Bi, Pb, Sn, Sb, Fe, and Ni) having different metal work functions to p-type Si using current-voltage characteristics. Most Schottky contacts show good characteristics with an ideality factor range from 1.057 to 1.831. Based on our measurements for p-type Si, the barrier heights and metal work functions show a linear relationship of current-voltage characteristics at room temperature with a slope (S=ϕb/ϕm) of 0.162, even though the Fermi level is partially pinned. From this linear dependency, the density of interface states was determined to be about 4.5 · 1013 1/eV per cm2, and the average pinning position of the Fermi level as 0.661 eV below the conduction band

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Growth Mechanism of Hydrogen Clusters

MRS Proceedings ◽

10.1557/proc-467-153 ◽

1997 ◽

Vol 467 ◽

Cited By ~ 1

Author(s):

N. H. Nickel ◽

G. B. Anderson ◽

N. M. Johnson ◽

J. Walker

Keyword(s):

Fermi Level ◽

Single Crystal ◽

Growth Mechanism ◽

Polycrystalline Silicon ◽

Single Crystal Silicon ◽

Surface Region ◽

Crystal Silicon ◽

Hydrogen Clusters ◽

Near Surface ◽

Crystallographic Planes

ABSTRACTIt is demonstrated that the exposure of polycrystalline silicon (poly-Si) to monatomic hydrogen results in the formation of H clusters. These H stabilized platelets appear in the near-surface region ( 100 nm) and are predominantly oriented along {111} crystallographic planes. Platelet concentrations of ≈5×1015, 1.5×1016-cm−3, and 2.4×1017 cm−3 were observed in nominally undoped poly-Si, phosphorous doped poly-Si (P=1017 cm−3), and phosphorous doped single crystal silicon (P>3×1018 cm−3), respectively. Results obtained on doped c-Si demonstrate that platelet generation occurs only at Fermi-level positions of Ec -EF < 0.4 eV.

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Nanoscale Mechanical Properties of In-Situ Tribofilms Generated from ZDDP and F-ZDDP with and without Antioxidants

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.905 ◽

2007 ◽

Vol 7 (12) ◽

pp. 4378-4390 ◽

Cited By ~ 26

Author(s):

Anuradha Somayaji ◽

Ramoun Mourhatch ◽

Pranesh B. Aswath

Keyword(s):

Electron Microscopy ◽

Wear Debris ◽

Surface Region ◽

Nucleation And Growth ◽

Near Surface ◽

Transmission Electron ◽

Dialkyl Dithiophosphates ◽

Wear Tests ◽

Diphenyl Amine

Tribofilms with thickness ranging from 100–200 nm were developed in-situ during wear tests using a zinc dialkyl dithiophosphates (ZDDP) and fluorinated ZDDP (F-ZDDP). The influence of the antioxidant alkylated diphenyl amine on the formation and properties of these tribofilm is examined. Results indicate that the thickness of the tribofilms formed when F-ZDDP is used is always thicker than the tribofilm formed with ZDDP. In addition, in the presence of antioxidants the tribofilm thickness is increased. The hardness of these tribofilms in the absence of the antioxidants is significantly higher at the near surface region (0–30 nm) when compared to the films formed in the presence of antioxidant. Nanoscratch tests conducted to examine the abrasion resistance of the tribofilms also indicate that the tribofilms formed by F-ZDDP are more resistant to scratch compared to films formed by ZDDP. In the presence of antioxidant, tribofilms formed by F-ZDDP are significantly thicker while both films behave in a similar fashion in nanoscratch tests. Transmission electron microscopy of the wear debris formed during the tests were examined and results indicate the nucleation and growth of nanoparticles of Fe3O4 with an approximate size of 5–10 nm embedded within an otherwise amorphous tribofilm.

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Amortization and Recrystallization of 6H-SiC by ion Beam Irradiation

MRS Proceedings ◽

10.1557/proc-339-197 ◽

1994 ◽

Vol 339 ◽

Cited By ~ 4

Author(s):

V. Heera ◽

R. Kögler ◽

W. Skorupa ◽

J. Stoemenos

Keyword(s):

Ion Irradiation ◽

Ion Beam ◽

Surface Region ◽

Ion Beam Irradiation ◽

Surface Layers ◽

Near Surface ◽

Transmission Electron ◽

Amorphous Surface ◽

Amorphous Sic

ABSTRACTThe evolution of the damage in the near surface region of single crystalline 6H-SiC generated by 200 keV Ge+ ion implantation at room temperature (RT) was investigated by Rutherford backscattering spectroscopy/chanelling (RBS/C). The threshold dose for amorphization was found to be about 3 · 1014 cm-2, Amorphous surface layers produced with Ge+ ion doses above the threshold were partly annealed by 300 keV Si+ ion beam induced epitaxial crystallization (IBIEC) at a relatively low temperature of 480°C For comparison, temperatures of at least 1450°C are necessary to recrystallize amorphous SiC layers without assisting ion irradiation. The structure and quality of both the amorphous and recrystallized layers were characterized by cross-section transmission electron microscopy (XTEM). Density changes of SiC due to amorphization were measured by step height measurements.

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Defects Introduced by Plasma Processing of Silicon

MRS Proceedings ◽

10.1557/proc-262-1027 ◽

1992 ◽

Vol 262 ◽

Cited By ~ 2

Author(s):

J. L. Benton

Keyword(s):

Bulk Material ◽

Surface Region ◽

Surface Damage ◽

Near Surface ◽

Enhanced Diffusion ◽

Interstitial Defect ◽

Comprehensive Picture ◽

Reaction Region ◽

Defect Reactions ◽

P Type

ABSTRACTThe electrical and optical properties of defects introduced by Reactive Ion Etching (RIE) in the near surface region of Si after dry etching with various gases and plasma conditions is studied with spreading Resistance (SR), photoluminescence (PL), and capacitance-voltage profiling (C-V). Plasma etching in chlorine and fluorine based gases produce donors at the surface in both n-type and p-type, Czochralski and float-zone silicon. Isochronal annealing reveals the presence of two distinct regions of dopant compensation. The surface damage region is confined to 1000 Å and survives heat treatment at 400°C, while the defect reaction region extends ≥ 1 μm in depth and recovers by 250°C. A comprehensive picture of the interstitial defect reactions in RIE silicon is completed. The interstitial defects, Ci and Bi, created in the ion damaged near surface region, undergo recombination enhanced diffusion caused by the presence of ultraviolet light in the plasma, resulting in the long range diffusion into the Si bulk. Subsequently, the interstitial atoms are trapped by the background impurities forming the defect pairs, CiOi, CSCi, or BiOi, which are observed experimentally. The depth of the diffusion-limited trapping and the probability of forming specific pairs depends on the relative concentrations of the reactants, oxygen, carbon or boron, present in the bulk material.

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Schottky Barrier Heights of Cr Contacts on n- and p-Type 6H-SiC

Chinese Physics Letters ◽

10.1088/0256-307x/14/6/017 ◽

1997 ◽

Vol 14 (6) ◽

pp. 460-463 ◽

Cited By ~ 1

Author(s):

Zhang Yong-gang ◽

Li Ai-zhen ◽

A G Milnes

Keyword(s):

Schottky Barrier ◽

Barrier Heights ◽

P Type

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Electrical and Structural Characterization of Boron Implanted Silicon Following Laser Thermal Processing

MRS Proceedings ◽

10.1557/proc-717-c1.10 ◽

2002 ◽

Vol 717 ◽

Cited By ~ 2

Author(s):

K. A. Gable ◽

K. S. Jones ◽

M. E. Law ◽

L. S. Robertson ◽

S. Talwar

Keyword(s):

Melting Temperature ◽

Thermal Processing ◽

Laser Annealing ◽

Substrate Surface ◽

Surface Region ◽

Process Window ◽

Near Surface ◽

Dopant Activation ◽

Transmission Electron ◽

Laser Thermal Processing

AbstractOne alternative to conventional rapid thermal annealing (RTA) of implants for ultra-shallow junction formation is that of laser annealing. Laser thermal processing (LTP) incorporates an excimer pulsed laser capable of melting the near surface region of the silicon (Si) substrate. The melt depth is dependent upon the energy density supplied by the irradiation source and the melting temperature of the substrate surface. A process window associated with this technique is able to produce similar junction depths over a range of energy densities due to the melting temperature depression established with pre-amorphization of the substrate surface prior to dopant incorporation. The process window of germanium (Ge) preamorphized, boron (B) doped Si was investigated. 200 mm (100) n-type Si wafers were preamorphized via 18 keV Ge+ implantation to 1x1015/cm2 and subsequently implanted with 1 keV B+ to doses of 1x1015/cm2, 3x1015/cm2, 6x1015/cm2, and 9x1015/cm2. The wafers were laser annealed from 0.50 J/cm2 to 0.88 J/cm2 using a 308 nm XeCl excimer irradiation source. Transmission electron microscopy (TEM) was used to determine the process window for each implant condition, and correlations between process window translation and impurity concentration were made. Four-point probe quantified dopant activation and subsequent deactivation upon post-LTP furnace annealing.

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