Transformation From Schottky to Ohmic Contact at High Temperature in Diamond Schottky Barrier Diode

Shuning Cui

doi:10.62051/a4b2zv15

Authors

Shuning Cui

DOI:

https://doi.org/10.62051/a4b2zv15

Keywords:

Diamond Schottky diode; Schottky barrier height; Schottky contact.

Abstract

Relations between Schottky contact and ohmic contact in diamond Schottky diode is attentively studied. Whether the metal-semiconductor contact forms metal carbide at high temperature on the interface of p-diamond is showed to determine the character of the contact. Formation of carbide and/or intermixing of metal and p-diamond at elevated temperature are believed to lower the Schottky barrier height and make Schottky contact “ohimicize” in a certain extent. This transformation can be advantageous for fabricating ideal ohmic contact, especially when boosted by annealing, but it can also be detrimental to maintaining high-quality Schottky contact at higher temperature. This suggests general criteria for identifying potential candidates for the two types of contact. Oxide and/or surface intermixture formed by metal and Oxygen-Terminals (OTs) on p-diamond, however, can resist the transformation trend at high temperature, thereby leading to better thermal stability. Nevertheless, the desorption of OTs at certain temperature may lead to re-reaction between metal and carbon, thus lowering the barrier again. Luckily, this temperature limit for certain metal is usually higher than the operating high-enough temperature and has less to do with the thermal stability and effectiveness of the functioning diode. Finally, careful selection of metal materials combined with adjustment of Schottky barrier height through high temperature can help fabricate desirable, robust and more economic diamond Schottky diode working at required higher temperature. Similar phenomenon may be observed for non-diamond Schottky diode as well and further researches can be conducted.

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References

[1] C. J. H. Wort, R. S. Balmer, Diamond as an electronic material, Materials Today 11 (2008) 22-28.

[2] P. Bo, L. Qi, J. Shumiao, F. Shuwei, W. Ruozheng, W. Hongxing, Research Progress of Diamond Schottky Barrier Diodes, Journal of Synthetic Crystals 52(5) (2023).

[3] S. Kono, T. Teraji, H. Kodama, K. Ichikawa, S. Ohnishi, A. Sawabe, Direct determination of the barrier height of Ti-based ohmic contact on p-type diamond (001), Diamond and Related Materials 60 (2015) 117-122.

[4] K. Das, V. Venkatesan, T. P. Humphreys, Ohmic contacts on diamond by B ion implantation and TiC-Au and TaSi2-Au metallization, J. Appl. Phys. 76(1994) 2208-2212.

[5] D. Zhao et al., Effects of rapid thermal annealing on the contact of tungsten/p-diamond, Appl. Surf. Sci. 443 (2018) 361-366.

[6] T. Tachibana, B. E. Williams, J. T. Glass, Correlation of the electrical properties of metal contacts on diamond films with the chemical nature of the metal-diamond interface. II. Titanium contacts: A carbide-forming metal, Phys. Rev. B 45 (1992) 11975-11981.

[7] Y. Wang et al., Ohmic contacts and interface properties of Au/Ti/p-diamond prepared by r.f. sputtering, Surf. Interface Anal. 29 (2000) 478-481.

[8] W. Wang et al., Palladium Ohmic contact on hydrogen-terminated single crystal diamond film, Diamond and Related Materials 59 (2015) 90-94.

[9] C. M. Zhen, X. Q. Wang, X. C. Wu, C. X. Liu, D. L. Hou, Au/p-diamond ohmic contacts deposited by RF sputtering, Appl. Surf. Sci. 255 (2008) 2916-2919.

[10] S. Koné et al., An assessment of contact metallization for high power and high temperature diamond Schottky devices, Diamond and Related Materials 27–28 (2012) 23-28.

[11] T. Teraji, Y. Garino, Y. Koide, T. Ito, Low-leakage p-type diamond Schottky diodes prepared using vacuum ultraviolet light/ozone treatment, J. Appl. Phys. 105 (2009) 126109.

[12] T. Teraji, Y. Koide, T. Ito, High‐temperature stability of Au/p‐type diamond Schottky diode, Physica Rapid Research Ltrs 3 (2009) 211-213.

[13] J. C. Piñero et al., Atomic composition of WC/ and Zr/O-terminated diamond Schottky interfaces close to ideality, Appl. Surf. Sci. 395 (2017) 200-207.

[14] A. Traoré, P. Muret, A. Fiori, D. Eon, E. Gheeraert, J. Pernot, Zr/oxidized diamond interface for high power Schottky diodes, Appl. Phys. Lett. 104 (2014) 052105.

[15] R. Monflier et al., Diamond Schottky diodes operating at 473 K, EPE Journal 27 (2017) 118-124.

[16] K. Ueda, K. Kawamoto, H. Asano, High-temperature and high-voltage characteristics of Cu/diamond Schottky diodes, Diamond and Related Materials 57 (2015) 28-31.

[17] K. Ueda, K. Kawamoto, T. Soumiya, H. Asano, High-temperature characteristics of Ag and Ni/diamond Schottky diodes, Diamond and Related Materials 38 (2013) 41-44.