TY - JOUR
T1 - Medium energy ion scattering for the high depth resolution characterisation of high-k dielectric layers of nanometer thickness
AU - Van Den Berg, J.A.
AU - Reading, M. A.
AU - Bailey, P.
AU - Noakes, T. Q. C.
AU - Adelmann, C.
AU - Popovici, M.
AU - Tielens, H.
AU - Conard, T.
AU - De Gendt, S.
AU - Van Elshocht, S.
PY - 2013/9/15
Y1 - 2013/9/15
N2 - Medium energy ion scattering (MEIS) using, typically, 100-200 keV H + or He+ ions derives it ability to characterise nanolayers from the fact that the energy after backscattering depends (i) on the elastic energy loss suffered in a single collision with a target atom and (ii) on the inelastic energy losses on its incoming and outgoing trajectories. From the former the mass of the atom can be determined and from the latter its depth. Thus MEIS yields depth dependent compositional and structural information, with high depth resolution (sub-nm near the surface) and good sensitivity for all but the lighter masses. It is particularly well suited for the depth analysis of high-k multilayers of nanometer thickness. Accurate quantification of the depth distributions of atomic species can be obtained using suitable spectrum simulation. In the present paper, important aspects of MEIS including quantification, depth resolution and spectrum simulation are briefly discussed. The capabilities of the technique in terms of the high depth resolution layer compositional and structural information it yields, is illustrated with reference to the detailed characterisation of a range of high-k nanolayer and multilayer structures for current microelectronic devices or those still under development: (i) HfO2 and HfSiOx for gate dielectric applications, including a TiN/Al2O3/HfO 2/SiO2/Si structure, (ii) TiN/SrTiO3/TiN and (iii) TiO2/Ru/TiN multilayer structures for metal-insulator-metal capacitors (MIMcaps) in DRAM applications. The unique information provided by the technique is highlighted by its clear capability to accurately quantify the composition profiles and thickness of nanolayers and complex multilayers as grown, and to identify the nature and extent of atom redistribution (e.g. intermixing, segregation) during layer deposition, annealing and plasma processing. The ability makes it a valuable tool in the development of the nanostructures that will become increasingly important as device dimensions continue to be scaled down. © 2013 Published by Elsevier B.V. All rights reserved.
AB - Medium energy ion scattering (MEIS) using, typically, 100-200 keV H + or He+ ions derives it ability to characterise nanolayers from the fact that the energy after backscattering depends (i) on the elastic energy loss suffered in a single collision with a target atom and (ii) on the inelastic energy losses on its incoming and outgoing trajectories. From the former the mass of the atom can be determined and from the latter its depth. Thus MEIS yields depth dependent compositional and structural information, with high depth resolution (sub-nm near the surface) and good sensitivity for all but the lighter masses. It is particularly well suited for the depth analysis of high-k multilayers of nanometer thickness. Accurate quantification of the depth distributions of atomic species can be obtained using suitable spectrum simulation. In the present paper, important aspects of MEIS including quantification, depth resolution and spectrum simulation are briefly discussed. The capabilities of the technique in terms of the high depth resolution layer compositional and structural information it yields, is illustrated with reference to the detailed characterisation of a range of high-k nanolayer and multilayer structures for current microelectronic devices or those still under development: (i) HfO2 and HfSiOx for gate dielectric applications, including a TiN/Al2O3/HfO 2/SiO2/Si structure, (ii) TiN/SrTiO3/TiN and (iii) TiO2/Ru/TiN multilayer structures for metal-insulator-metal capacitors (MIMcaps) in DRAM applications. The unique information provided by the technique is highlighted by its clear capability to accurately quantify the composition profiles and thickness of nanolayers and complex multilayers as grown, and to identify the nature and extent of atom redistribution (e.g. intermixing, segregation) during layer deposition, annealing and plasma processing. The ability makes it a valuable tool in the development of the nanostructures that will become increasingly important as device dimensions continue to be scaled down. © 2013 Published by Elsevier B.V. All rights reserved.
KW - High-k nanolayers
KW - Medium energy ion scattering analysis
KW - High resolution depth profiling
KW - Metal–insulator–metal capacitor (MIMcap) layers
UR - https://www.scopus.com/inward/record.uri?eid=2-s2.0-84880330600&doi=10.1016%2fj.apsusc.2013.02.003&partnerID=40&md5=4aac87946eb7b1ec7508c2889f3b9086
U2 - 10.1016/j.apsusc.2013.02.003
DO - 10.1016/j.apsusc.2013.02.003
M3 - Article
VL - 281
SP - 8
EP - 16
JO - Applications of Surface Science
JF - Applications of Surface Science
SN - 0169-4332
ER -