Low Specific Contact Resistivity Measurements using a New Test Structure and its Reduction to 10−9 ohm-cm2 in p-type SiGe/Metal Contacts using Flash Lamp Annealing

We present a numerical method to extract specific contact resistivity (SCR) for three-dimensional (3-D) contact structures using a two-electrode test structure. This method was developed using Finite Element Modeling (FEM). Experimental measurements were performed for contacts of 200 nm nickel (Ni) to p+-type germanium (Ge) substrates and 200 nm of Titanium (Ti) on 4H-Silicon Carbide (SiC). The SCR obtained was (2.3-27)?10-6 ??cm2 for the Ni-Ge contacts and (1.3-2.4)?10-3 ??cm2 for the Ti-SiC.

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Two-contact Circular Test Structure for Determining Specific Contact Resistivity

MRS Proceedings ◽

10.1557/opl.2013.864 ◽

2013 ◽

Vol 1553 ◽

Author(s):

Y. Pan ◽

G. K. Reeves ◽

P. W. Leech ◽

P. Tanner ◽

A. S. Holland

Keyword(s):

Ohmic Contacts ◽

Electrical Characterization ◽

Contact Resistivity ◽

Test Structure ◽

Metal Contacts ◽

Circular Test ◽

Specific Contact ◽

Specific Contact Resistivity ◽

Analytical Expressions ◽

Geometrical Dimensions

ABSTRACTAs ohmic contacts decrease in size and approach nanoscale dimensions, accurate electrical characterization is essential, requiring the development of suitable test structures for this task. We present here a new test structure derived from the standard three-contact circular transmission line model (CTLM) [1], for determining the specific contact resistivity of ohmic contacts. This test structure minimizes sources of error which arise from the CTLM by – (i) reducing the number of contacts within one test pattern from three to two, (ii) ensuring the assumption of equipotential metal contacts used in modelling is more easily attained experimentally, and (iii) allowing the fabrication of reduced geometrical dimensions essential for determining low specific contact resistivity values. The analytical expressions are presented and experiment results are undertaken to demonstrate the accuracy of the technique. There are no error corrections required for determining contact parameters using the presented test structure.

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Development of Low Resistance Al/Ti Stacked Metal Contacts to p-Type 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.697 ◽

2007 ◽

Vol 556-557 ◽

pp. 697-700 ◽

Cited By ~ 2

Author(s):

Michael R. Jennings ◽

Amador Pérez-Tomás ◽

D. Walker ◽

Lin Zhu ◽

Peter A. Losee ◽

...

Keyword(s):

Microstructural Analysis ◽

Contact Resistivity ◽

Metal Contact ◽

Metal Contacts ◽

Low Resistance ◽

Specific Contact ◽

Specific Contact Resistivity ◽

P Type ◽

Post Deposition

In this work, we have investigated triple and innovative multiple stacked contacts onto ptype SiC in order to evaluate whether or not there is any improvement in morphology or specific contact resistivity. The stacked metal contacts are based on Al, Ti and Ni with the specific contact resistivity measured at a low value of 5.02×10-6'cm2 for an Al(100 nm)/Ti(100 nm)/Al(10 nm) (where a “/” indicates the deposition sequence) triple stacked metal contact. XRD microstructural analysis and SEM measurements have been carried out and it has been discovered that the contacts, which formed the compound Ti3SiC2 at the metal/SiC interface, more readily display low-resistance ohmic characteristics after a post deposition anneal. Although the same amount of Ti (100 nm in total) has been deposited closer to the metal/SiC interface, none of the multiple stacked structures displayed ohmic behaviour after a post deposition anneal.

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