TY - JOUR
T1 - Study on solid-phase reactions in Ti/p+-Si1-x-yGexCy/Si(100) contacts
AU - Tobioka, A.
AU - Tsuchiya, Y.
AU - Ikeda, Hiroya
AU - Sakai, A.
AU - Zaima, S.
AU - Murota, J.
AU - Yasuda, Y.
N1 - Funding Information:
This work was partly supported by a Grant-in-Aid for Scientific Research on Priority Areas (Number 11232203) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
PY - 2002/2/14
Y1 - 2002/2/14
N2 - We have investigated the solid phase reactions between Ti and p+-Si1-x-yGexCy (x=0-0.470, y=0-0.020) alloys in Ti/p+-Si1-x-yGexCy/Si(100) systems using two-step annealing. For Si-rich samples, a C49-Ti(SiGe)2 phase is formed after the first annealing at 550 °C. After the second annealing, the C49-Ti(SiGe)2 phase is transformed into a C54-Ti(SiGe)2 phase, which has low sheet resistance. For Ge-rich samples, on the other hand, Ti6Ge5 is formed after the first annealing. At the same time, discontinuous Si-rich SiGeC regions are formed at the Ti6Ge5/p+-Si1-x-y GexCy interface. After the second annealing, the C49-Ti(SiGe)2 film appears in the form of agglomerated morphology. The agglomeration is considered to be due to preferential consumption of the discontinuous Si-rich SiGeC regions during the formation of the C49-Ti(SiGe)2 phase. As a result of the agglomeration of the C49-Ti(SiGe)2 film, the C54-Ti(SiGe)2 film also becomes discontinuous. Moreover, it is found that the C atoms in the p+-Si1-x-yGexCy layer have an effect of elevating the transformation temperature from C49-Ti(SiGe)2 to C54-Ti(SiGe)2. By contrast, the sheet resistance of the C54-Ti(SiGe)2 film is hardly influenced by Ge and C atoms.
AB - We have investigated the solid phase reactions between Ti and p+-Si1-x-yGexCy (x=0-0.470, y=0-0.020) alloys in Ti/p+-Si1-x-yGexCy/Si(100) systems using two-step annealing. For Si-rich samples, a C49-Ti(SiGe)2 phase is formed after the first annealing at 550 °C. After the second annealing, the C49-Ti(SiGe)2 phase is transformed into a C54-Ti(SiGe)2 phase, which has low sheet resistance. For Ge-rich samples, on the other hand, Ti6Ge5 is formed after the first annealing. At the same time, discontinuous Si-rich SiGeC regions are formed at the Ti6Ge5/p+-Si1-x-y GexCy interface. After the second annealing, the C49-Ti(SiGe)2 film appears in the form of agglomerated morphology. The agglomeration is considered to be due to preferential consumption of the discontinuous Si-rich SiGeC regions during the formation of the C49-Ti(SiGe)2 phase. As a result of the agglomeration of the C49-Ti(SiGe)2 film, the C54-Ti(SiGe)2 film also becomes discontinuous. Moreover, it is found that the C atoms in the p+-Si1-x-yGexCy layer have an effect of elevating the transformation temperature from C49-Ti(SiGe)2 to C54-Ti(SiGe)2. By contrast, the sheet resistance of the C54-Ti(SiGe)2 film is hardly influenced by Ge and C atoms.
KW - Cross-sectional transmission electron microscope
KW - Metal/semiconductor contact
KW - SiGeC alloy
KW - Solid-phase reaction
KW - Titanium
KW - X-ray diffraction
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U2 - 10.1016/S0921-5107(01)00832-7
DO - 10.1016/S0921-5107(01)00832-7
M3 - Article
AN - SCOPUS:0037074828
VL - 89
SP - 373
EP - 377
JO - Materials Science and Engineering B: Solid-State Materials for Advanced Technology
JF - Materials Science and Engineering B: Solid-State Materials for Advanced Technology
SN - 0921-5107
IS - 1-3
ER -