Low Specific Contact Resistance to 3C-SiC Grown on (100) Si Substrates

In this work, ohmic contacts, formed by 100nm Ni layer RTA annealed or not, were investigated on 3C-SiC epilayers exhibiting different nitrogen doping levels. The epilayers were grown on (100) silicon. Doping level (N) and eventual dopant contamination (Al) were analyzed by C-V and/or SIMS. The specific contact resistance was determined by using Transmission Line Model (TLM) patterns for each condition (doping and annealing). Our results clearly evidence that very low specific contact resistance (~10-51.cm²) is obtained on highly doped 3C-SiC epilayers, enlightening the interest of both material and Ni contacts for future devices fabrication.

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Investigation of specific contact resistance of ohmic contacts to B-doped homoepitaxial diamond using transmission line model

Diamond and Related Materials ◽

10.1016/j.diamond.2004.07.001 ◽

2004 ◽

Vol 13 (11-12) ◽

pp. 2121-2124 ◽

Cited By ~ 18

Author(s):

Y.G. Chen ◽

M. Ogura ◽

S. Yamasaki ◽

H. Okushi

Keyword(s):

Contact Resistance ◽

Transmission Line ◽

Ohmic Contacts ◽

Specific Contact Resistance ◽

Transmission Line Model ◽

Line Model ◽

Specific Contact

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Ohmic Contacts on N-Type Hg0.4Cd0.6Te.

MRS Proceedings ◽

10.1557/proc-216-155 ◽

1990 ◽

Vol 216 ◽

Cited By ~ 3

Author(s):

Patrick W. Leech ◽

Geoffrey K. Reeves ◽

Martyn H. Kibel

Keyword(s):

Contact Resistance ◽

Transmission Line ◽

Schottky Barrier ◽

Optical Communications ◽

Ohmic Contacts ◽

Specific Contact Resistance ◽

Electrical Characteristics ◽

Schottky Barrier Diodes ◽

Transmission Line Model ◽

Specific Contact

ABSTRACTThe electrical characteristics of In, Sn, Au and Pt contacts on n-type Hg0.4Cd0.6Te formed in the presence and absence of prior In2+ implantation have been examined. Measurements of specific contact resistance made using a Transmission Line Model have shown that the unimtlanted In/Hg0.4Cd0.6 and Sn/Hg0.4Cd0.6 junctions gave values of pc = 3.0x10−3 to 4.0x10−3 ohm.cm2. Auger sputter profiles of the asdeposited In/Hg0.4Cd0.6 and Sn/Hg0.4Cd0.6 interfaces have shown a significant in-diffusion of the metal overlayer. The influence of shallow In2+ implantation prior to metallization was an increase in pc which occurred above a dose of 1013 ions/cm2. In contrast, Pt and Au formed Schottky barrier diodes on n-type Hg0.4Cd0.6 with øb=0.69eV for Pt and øb=0.79eV for Au. With prior In2+ implantation, both Pt and Au contacts exhibited an ohmic behaviour with pc= 2x10−1 ohm.cm2. These results have significance in the fabrication of devices for 1.0 -2.5μm optical communications.

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Electrical Modelling and Characterisation of Alloyed Ohmic Contacts

MRS Proceedings ◽

10.1557/proc-318-153 ◽

1993 ◽

Vol 318 ◽

Cited By ~ 3

Author(s):

Geoffrey K. Reeves ◽

Patrick W. Leech ◽

H. Barry Harrison

Keyword(s):

Contact Resistance ◽

Transmission Line ◽

Ohmic Contact ◽

Ohmic Contacts ◽

Realistic Model ◽

Specific Contact Resistance ◽

Transmission Line Model ◽

Semiconductor Interface ◽

Line Model ◽

Specific Contact

ABSTRACTThis paper briefly reviews the standard Transmission Line Model (TLM) commonly used to measure the specific contact resistance of a planar ohmic contact. It is proposed that in the case of a typical Au-Ge-Ni alloyed ohmic contact, a more realistic model would need to take into account the presence of the alloyed layer at the metal-semiconductor interface. An alternative is described which is based on three contact layers and the two interfaces between them, thus forming a Tri-Layer Transmission Line Model (TLTLM). Expressions are given for the contact resistance Rc and the contact end resistance Re of this structure, together with a current division factor, f. Values for the parameters of this model are inferred from experimentally reported values of Rc and Re for two types of contact.

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Modelling Geometrical Effects of Parasitic and Contact Resistance of FET Devices

MRS Proceedings ◽

10.1557/proc-427-147 ◽

1996 ◽

Vol 427 ◽

Cited By ~ 1

Author(s):

Geoffrey K. Reeves ◽

H. Barry Harrison ◽

Patrick W. Leech

Keyword(s):

Contact Resistance ◽

Material Properties ◽

Ohmic Contacts ◽

Difficult Problem ◽

Specific Contact Resistance ◽

Metal Silicide ◽

Transmission Line Model ◽

Specific Contact ◽

Geometrical Effects ◽

Contact Parameters

AbstractThe continual trend in decreasing the dimensions of semiconductor devices results in a number of technological problems. One of the more significant of these is the increase in contact resistance, Rc. In order to understand and counteract this increase, Rc needs to be quantitatively modelled as a function of the geometrical and material properties of the contact. However the use of multiple semiconductor layers for ohmic contacts makes the modelling and calculation of Rc a more difficult problem. In this paper, a Tri-Layer Transmission Line Model (TLTLM) is used to analyse a MOSFET ohmic contact and gatedrain region. A quantitative assessment of the influence on Rc of important contact parameters such as the metal-silicide specific contact resistance, the silicide-silicon specific contact resistance and the gate-drain length can thus be made. The paper further describes some of the problems that may be encountered in defining Rc when the dimensions of certain types of contact found in planar devices decrease.

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A New Electrical Model for Calculating the Sheet Resistance Parameter in Alloyed Ohmic Contacts

MRS Proceedings ◽

10.1557/proc-337-275 ◽

1994 ◽

Vol 337 ◽

Cited By ~ 1

Author(s):

Geoffrey K. Reeves ◽

H. Barry Harrison

Keyword(s):

Transmission Line ◽

Sheet Resistance ◽

Ohmic Contact ◽

Ohmic Contacts ◽

Metal Layer ◽

Semiconductor Layer ◽

Specific Contact Resistance ◽

Transmission Line Model ◽

Line Model ◽

Specific Contact

ABSTRACTThis paper briefly reviews the standard Transmission Line Model (TLM) commonly used to measure the specific contact resistance ρc and the sheet resistance Rsk beneath a planar ohmic contact. In the case of an alloyed ohmic contact, a more realistic three layer (Tri-Layer Transmission Line Model (TLTLM)) can be used for the analysis. This model is based on three layers (metal layer, alloyed semiconductor layer and the unalloyed semiconductor layer) and the two interfaces between them. By using appropriate TLTLM parameters, it is possible to calculate the sheet resistance Rsk that has been experimentally derived from the standard TLM. The new TLTLM model predicts that values of Rsk greater and less than Rsh (the unmodified epitaxial layer sheet resistance) are possible in agreement with experimentally reported observations.

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The Reliability of Multilevel Metallization on InGaAs/GaAs Layers

MRS Proceedings ◽

10.1557/proc-337-387 ◽

1994 ◽

Vol 337 ◽

Author(s):

Edward Y. Chang ◽

J.S. Chen ◽

J.W. Wu ◽

K.C. Lin

Keyword(s):

Contact Resistance ◽

Ohmic Contacts ◽

Molecular Beam ◽

Specific Contact Resistance ◽

Transmission Line Model ◽

X Ray Diffraction ◽

X Ray ◽

Specific Contact ◽

Secondary Ion ◽

Contact Metal

ABSTRACTNon-alloyed ohmic contacts using Ti/Pt/Au and Ni/Ge/Au on InGaAs/GaAs layers grown by Molecular Beam Epitaxy (MBE) have been investigated. The n-type InGaAs film has a doping concentration higher than 1X1019 cm-3. Specific contact resistance below 2X10-7 Ωcm2 could be easily achieved with Ti/Pt/Au. Due to the layer intermixing and outdiffusion of In and Ga, the specific contact resistance and sheet resistance increase after thermal treatment. When Ni/Ge/Au is used as the contact metal, the outdiffusion of In and Ga atoms is more severe than that of Ti/Pt/Au. After annealing at 450°C for two minutes, the Au4In formed and the characteristics of the contact became worse. All the phenomena illustrated above have been observed and investigated by Transmission Line Model, X-ray diffraction, Auger Electron Spectroscopy and Secondary Ion Mass Spectrum. As far as the thermal stability is concerned, it is convinced that Ti/Pt/Au is the best one of these two non-alloyed ohmic contact studied.

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