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The high-temperature stability of a Pt/TaSi2/Ni/SiC ohmic contact metallization scheme was characterized using a combination of current-voltage measurements, Auger electron spectroscopy, and transmission electron microscopy imaging and associated analytical techniques. Increasing the thicknesses of the Pt and TaSi2 layers promoted electrical stability of the contacts, which remained ohmic at 600A degrees C in air for the extent of heat treatment; the specific contact resistance showed only a gradual increase from an initial value of 5.2 x 10(-5) Omega cm(2). We observed a continuous silicon oxide layer in the thinner contact structures, which failed after 36 h of heating. Meanwhile, thicker contacts with enhanced stability contained a much lower oxygen concentration that was distributed across the contact layers, precluding the formation of an electrically insulating contact structure., The original publication is available at www.springerlink.com:Ariel Virshup, Fang Liu, Dorothy Lukco, Kristina Buchholt, Anita Lloyd Spetz and Lisa M Porter, Improved Thermal Stability Observed in Ni-Based Ohmic Contacts to n-Type SiC for High-Temperature Applications, 2011, JOURNAL OF ELECTRONIC MATERIALS, (40), 4, 400-405.http://dx.doi.org/10.1007/s11664-010-1449-0Copyright: Springer Science Business Mediahttp://www.springerlink.com

The high-temperature stability of a Pt/TaSi2/Ni/SiC ohmic contact metallization scheme was characterized using a combination of current-voltage measurements, Auger electron spectroscopy, and transmission electron microscopy imaging and associated analytical techniques. Increasing the thicknesses of the Pt and TaSi2 layers promoted electrical stability of the contacts, which remained ohmic at 600A degrees C in air for the extent of heat treatment; the specific contact resistance showed only a gradual increase from an initial value of 5.2 x 10(-5) Omega cm(2). We observed a continuous silicon oxide layer in the thinner contact structures, which failed after 36 h of heating. Meanwhile, thicker contacts with enhanced stability contained a much lower oxygen concentration that was distributed across the contact layers, precluding the formation of an electrically insulating contact structure., The original publication is available at www.springerlink.com:Ariel Virshup, Fang Liu, Dorothy Lukco, Kristina Buchholt, Anita Lloyd Spetz and Lisa M Porter, Improved Thermal Stability Observed in Ni-Based Ohmic Contacts to n-Type SiC for High-Temperature Applications, 2011, JOURNAL OF ELECTRONIC MATERIALS, (40), 4, 400-405.http://dx.doi.org/10.1007/s11664-010-1449-0Copyright: Springer Science Business Mediahttp://www.springerlink.com

The high-temperature stability of a Pt/TaSi2/Ni/SiC ohmic contact metallization scheme was characterized using a combination of current-voltage measurements, Auger electron spectroscopy, and transmission electron microscopy imaging and associated analytical techniques. Increasing the thicknesses of the Pt and TaSi2 layers promoted electrical stability of the contacts, which remained ohmic at 600A degrees C in air for the extent of heat treatment; the specific contact resistance showed only a gradual increase from an initial value of 5.2 x 10(-5) Omega cm(2). We observed a continuous silicon oxide layer in the thinner contact structures, which failed after 36 h of heating. Meanwhile, thicker contacts with enhanced stability contained a much lower oxygen concentration that was distributed across the contact layers, precluding the formation of an electrically insulating contact structure., The original publication is available at www.springerlink.com:Ariel Virshup, Fang Liu, Dorothy Lukco, Kristina Buchholt, Anita Lloyd Spetz and Lisa M Porter, Improved Thermal Stability Observed in Ni-Based Ohmic Contacts to n-Type SiC for High-Temperature Applications, 2011, JOURNAL OF ELECTRONIC MATERIALS, (40), 4, 400-405.http://dx.doi.org/10.1007/s11664-010-1449-0Copyright: Springer Science Business Mediahttp://www.springerlink.com

The high-temperature stability of a Pt/TaSi2/Ni/SiC ohmic contact metallization scheme was characterized using a combination of current-voltage measurements, Auger electron spectroscopy, and transmission electron microscopy imaging and associated analytical techniques. Increasing the thicknesses of the Pt and TaSi2 layers promoted electrical stability of the contacts, which remained ohmic at 600A degrees C in air for the extent of heat treatment; the specific contact resistance showed only a gradual increase from an initial value of 5.2 x 10(-5) Omega cm(2). We observed a continuous silicon oxide layer in the thinner contact structures, which failed after 36 h of heating. Meanwhile, thicker contacts with enhanced stability contained a much lower oxygen concentration that was distributed across the contact layers, precluding the formation of an electrically insulating contact structure., The original publication is available at www.springerlink.com:Ariel Virshup, Fang Liu, Dorothy Lukco, Kristina Buchholt, Anita Lloyd Spetz and Lisa M Porter, Improved Thermal Stability Observed in Ni-Based Ohmic Contacts to n-Type SiC for High-Temperature Applications, 2011, JOURNAL OF ELECTRONIC MATERIALS, (40), 4, 400-405.http://dx.doi.org/10.1007/s11664-010-1449-0Copyright: Springer Science Business Mediahttp://www.springerlink.com

The high-temperature stability of a Pt/TaSi2/Ni/SiC ohmic contact metallization scheme was characterized using a combination of current-voltage measurements, Auger electron spectroscopy, and transmission electron microscopy imaging and associated analytical techniques. Increasing the thicknesses of the Pt and TaSi2 layers promoted electrical stability of the contacts, which remained ohmic at 600A degrees C in air for the extent of heat treatment; the specific contact resistance showed only a gradual increase from an initial value of 5.2 x 10(-5) Omega cm(2). We observed a continuous silicon oxide layer in the thinner contact structures, which failed after 36 h of heating. Meanwhile, thicker contacts with enhanced stability contained a much lower oxygen concentration that was distributed across the contact layers, precluding the formation of an electrically insulating contact structure., The original publication is available at www.springerlink.com:Ariel Virshup, Fang Liu, Dorothy Lukco, Kristina Buchholt, Anita Lloyd Spetz and Lisa M Porter, Improved Thermal Stability Observed in Ni-Based Ohmic Contacts to n-Type SiC for High-Temperature Applications, 2011, JOURNAL OF ELECTRONIC MATERIALS, (40), 4, 400-405.http://dx.doi.org/10.1007/s11664-010-1449-0Copyright: Springer Science Business Mediahttp://www.springerlink.com

We investigated the thermal stability of Pt/TaSi (x) /Ni/SiC ohmic contacts, which have been implemented in SiC-based gas sensors developed for applications in diesel engines and power plants. The contacts remained ohmic on lightly doped n-type (similar to 1 x 10(16) cm(-3)) 4H-SiC for over 1000 h in air at 300A degrees C. Although a gradual increase in specific contact resistance from 3.4 x 10(-4) Omega cm(2) to 2.80 x 10(-3) Omega cm(2) was observed, the values appeared to stabilize after similar to 800 h of heating in air at 300A degrees C. The contacts heated at 500A degrees C and 600A degrees C, however, showed larger increases in specific contact resistance followed by nonohmic behavior after 240 h and 36 h, respectively. Concentration profiles from Auger electron spectroscopy and electron energy-loss spectroscopy show that loss of ohmic behavior occurs when the entire tantalum silicide layer has oxidized.