2002 Fiscal Year Final Research Report Summary
Study of low resistance contact structure using composition-modulated interface layer for 0.1-μm generation ULSI
| Project/Area Number |
12555005
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 展開研究 |
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| Research Field |
Applied materials science/Crystal engineering
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| Research Institution | Nagoya University |
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Principal Investigator |
YASUDA Yukio Nagoya University, Graduate School of Engineering Professor, 工学研究科, 教授 (60126951)
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| Co-Investigator(Kenkyū-buntansha) |
NAKATSUKA Osamu Nagoya University, Center for Integrated Research in Science and Engineering Assistant Professor, 理工科学総合研究センター, 助手 (20334998)
IKEDA Hiroya Nagoya University, Graduate School of Engineering Assistant Professor, 工学研究科, 助手 (00262882)
SAKAI Akira Nagoya University, Graduate School of Engineering Associate Professor, 工学研究科, 助教授 (20314031)
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| Project Period (FY) |
2000 – 2002
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| Keywords | Ultra low resistance contact / modulated interface / Silicon germanium / Rapid thermal annealing / Titanium / Silicide / Germanosilicide / Source / Drain |
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| Research Abstract |
In this project, in order to realize reducing the parasitic resistance such as the contact resistivity at the metal/Si contact and the ultra shallow junction at source/drain regions, we aimed to the establishment of the applicable contact structure for sub-0.1 μm ULSI devices. We have clarified the relationship between the solid phase reactions and the electrical properties at the Ti/SiGe(C)/Si contact structure.
(1) The reaction products change from Ti5Ge_6, to C49-TiSi_2, C54-Ti(Si_<1_y>Ge_y)_2 with an increase in annealing temperature. The transformation temperature to C54-Ti(Si_<1-y>Ge_y)_2 in this structure is higher than that in the Ti/SiGe/Si structure. The Ti(SiGe)_2/Ge-rich SiGe/Si structure with the composition-modulated interface of Ge can be formed with annealing the Ti/Ge/Si structure.
(2) The Schottky barrier height estimated from the I-V measurement of the Ti/p-SiGe/p-Si structure decreases with the increase in the Ge composition. This structure is expected to be effective to reduce the contact resistivity.
(3) In the Ti/SiGeC/Si sample with the low Ge composition, C49-Ti(SiGe)_2 is formed after the 550℃-annealing and the transformation to C54-phase occurs after 750℃ RTA. On the other hand, in the case of the high Ge composition, Ti_6Ge_5 is formed at 550℃, C49-Ti(SiGe)_2 is formed with RTA at 650〜700℃, and the transformation to the C54-phase completes at 750℃. Almost Ge in the SiGe layer can be mixed in the C54-phase by using the RTA method.
(4) In the Ti/SiGeC/Si sample with the high Ge composition, while the Ti_6Ge_5 is formed with the conformal layer-structure, -grains of C49- and C54-phase agglomerate and the discontinuous film is formed. The reason why that occurs is the inhomogenization of the Ge composition in the reaction layer with the formation of the Ti_6Ge_5. On the other hand, in the sample with the low Ge composition, the conformal and flat layer of C49- and C54-phase can be formed.
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