TY - JOUR
T1 - Schottky barrier engineering with a metal nitride–double interlayer–semiconductor contact structure to achieve high thermal stability and ultralow contact resistivity
AU - Park, Euyjin
AU - Kim, Seung Hwan
AU - Yu, Hyun Yong
N1 - Funding Information:
This work was supported by the Basic Science Research Program within the Ministry of Science, ICT, and Future Planning through the National Research Foundation of Korea [Grant number 2020R1A2C2004029 ]; and the SK Hynix Inc., Korea .
Publisher Copyright:
© 2020
PY - 2020/11/30
Y1 - 2020/11/30
N2 - A new contact structure of a metal nitride-double interlayer-semiconductor structure with high thermal stability and ultralow contact resistivity is developed as a next-generation contact scheme via application of interface engineering. As conventional metal–interlayer–semiconductor structures exhibit degradation under thermal stressing owing to the intermixing of materials, three approaches for achieving enhanced thermal stability and ultralow contact resistance are applied. First, a metal nitride with high thermal stability and low reactivity is used as the contact metal. Second, a material with high crystallization temperature is used for the interlayer to prevent the grain boundary diffusion of metal through the interlayer. Lastly, a double interlayer structure is adopted to reduce the Schottky barrier height by utilizing the dipole effect. The corresponding contact was demonstrated to successfully sustain its structure after annealing of 550 ℃. Moreover, it exhibited a specific contact resistivity of 2.20 × 10−8 Ω·cm2, which is a reduction of ~198× and ~2.72× to those of the metal–semiconductor structure and the metal–interlayer–semiconductor structure, respectively. The proposed contact structure and interface engineering techniques in this study provide a valid method to achieve high thermal stability while maintaining low contact resistivity, which is a priority requirement for the emerging nanoscale technology.
AB - A new contact structure of a metal nitride-double interlayer-semiconductor structure with high thermal stability and ultralow contact resistivity is developed as a next-generation contact scheme via application of interface engineering. As conventional metal–interlayer–semiconductor structures exhibit degradation under thermal stressing owing to the intermixing of materials, three approaches for achieving enhanced thermal stability and ultralow contact resistance are applied. First, a metal nitride with high thermal stability and low reactivity is used as the contact metal. Second, a material with high crystallization temperature is used for the interlayer to prevent the grain boundary diffusion of metal through the interlayer. Lastly, a double interlayer structure is adopted to reduce the Schottky barrier height by utilizing the dipole effect. The corresponding contact was demonstrated to successfully sustain its structure after annealing of 550 ℃. Moreover, it exhibited a specific contact resistivity of 2.20 × 10−8 Ω·cm2, which is a reduction of ~198× and ~2.72× to those of the metal–semiconductor structure and the metal–interlayer–semiconductor structure, respectively. The proposed contact structure and interface engineering techniques in this study provide a valid method to achieve high thermal stability while maintaining low contact resistivity, which is a priority requirement for the emerging nanoscale technology.
KW - Fermi-level pinning
KW - Oxygen areal density
KW - Schottky barrier height lowering
KW - Source/drain contact
KW - Specific contact resistivity
KW - Thermal stability
UR - http://www.scopus.com/inward/record.url?scp=85088875641&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2020.147329
DO - 10.1016/j.apsusc.2020.147329
M3 - Article
AN - SCOPUS:85088875641
SN - 0169-4332
VL - 531
JO - Applied Surface Science
JF - Applied Surface Science
M1 - 147329
ER -