標題: Effects of Rapid Thermal Annealing on Ar Inductively Coupled Plasma-Treated n-Type 4H-SiC Schottky and Ohmic Contacts
作者: Cheng, Jung-Chien
Tsui, Bing-Yue
電子工程學系及電子研究所
Department of Electronics Engineering and Institute of Electronics
關鍵字: Inductively coupled plasma (ICP) treatment;ohmic contact;Schottky-barrier diode (SBD);Schottky-barrier height (SBH);silicon carbide (SiC);specific contact resistance
公開日期: 1-Sep-2018
摘要: The effects of Ar inductively coupled plasma (ICP) treatment followed by a 600 degrees C-1000 degrees C rapid thermal annealing (RTA) on the n-type 4H-silicon carbide (SiC) Schottky-barrier diodes and n(+)-implanted ohmic contacts were investigated. The ICP treatment created a 3-nm-thick, sp(2)-C-rich, and amorphous layer at the SiC surface. The RTA repaired the bombardment-induced damages before metal deposition to avoid current degradation. This ICP + RTA-treated surface strongly pinned the Schottky- barrier height (SBH) at a minimum of 0.88 eV. In theory, the low SBH is beneficial to decrease the specific contact resistance (rho(C)). rho(C) of the ICP + RTA-treated Ti ohmic contacts decreased to lower than 10(-5) Omega.cm(2) after 400 degrees C post-metal deposition annealing (PMDA). However, the additional O atoms, fixed in the amorphous layer by RTA, affected the rho(C) reduction. Fortunately, due to the chemical affinity for O of Ti, the in-diffused Ti could contend for the O atoms against the Si-O bonds during the PMDA. Therefore, the oxidized barricade was decomposed gradually, leading to the lowest rho(C), 1.3 x 10(-6) Omega.cm(2), after 600 degrees C PMDA. The lowest rho(C) is 25x and 8x lower than that of the Ni silicide and the nontreated Ti contacts, respectively, at the same doping concentration.
URI: http://dx.doi.org/10.1109/TED.2018.2859272
http://hdl.handle.net/11536/148039
ISSN: 0018-9383
DOI: 10.1109/TED.2018.2859272
期刊: IEEE TRANSACTIONS ON ELECTRON DEVICES
Volume: 65
起始頁: 3739
結束頁: 3745
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