SEMICONDUCTING RHENIUM SILICIDE THIN-FILMS ON SI(111)

被引:25
作者
TAN, TAN
VEUILLEN, JY
MURET, P
KENNOU, S
SIOKOU, A
LADAS, S
RAZAFINDRAMISA, FL
BRUNEL, M
机构
[1] UNIV PATRAS, HT, ICE, SURFACE SCI LAB, GR-26500 RIO PATRAS, GREECE
[2] UNIV PATRAS, DEPT CHEM ENGN, GR-26500 RIO PATRAS, GREECE
[3] CNRS, CRISTALLOG LAB, F-38042 GRENOBLE 9, FRANCE
[4] UNIV IOANNINA, DEPT PHYS, GR-45110 IOANNINA, GREECE
关键词
D O I
10.1063/1.358780
中图分类号
O59 [应用物理学];
学科分类号
摘要
The crystallographic, electronic, and optical properties of thin ReSi 2 films (∼20-300 Å) have been investigated in situ by low energy electron diffraction (LEED) and photoelectron spectroscopy (XPS and UPS), ex situ by glancing incidence x-ray diffraction (GIXD), and optical absorption measurements. Thin Re layers were evaporated under ultrahigh vacuum on Si(111) (7×7) surfaces, maintained at room temperature, or heated at 650°C. The films were subsequently annealed at increasing high temperature and the silicide formation was followed by in situ surface techniques. For very thin films (≲35 Å) LEED shows a faint (1×1) pattern after annealing at 750°C, which improves slightly up to ∼900°C. For thick films (∼50-300 Å) only a bright background is observed. XPS indicates that the ReSi2 composition is attained upon annealing at 600°C. In the Re-Si bonding the charge transfer is negligible: the energy positions of the corelevels (Si 2p and Re 4f) are the same in the compound and in the elements. As the energy shift of the Si KLL Auger is negligible also, the extra-atomic relaxation energy for Si atoms is the same in silicide as in silicon, indicating that ReSi2 has a semiconducting character. UPS results confirm this assumption: the density of states near EF decreases strongly upon ReSi2 formation and at the same time the valence band edge shifts from EF to lower binding energy. GIXD gives sharp diffraction peaks, characteristic of ReSi2 (110) in epitaxy on Si(111). This technique also reveals that the films present an additional orientation near the interface. Optical absorption measurements performed on ReSi2 films of ∼300 Å thick indicate that this silicide is a semiconductor with an indirect energy gap of 0.15 eV, in agreement with previous studies. © 1995 American Institute of Physics.
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页码:2514 / 2518
页数:5
相关论文
共 17 条
[1]  
ALVAREZ J, 1992, SURF SCI, V270, P1011
[2]   ELECTRONIC-STRUCTURE OF REFRACTORY-METAL SILICIDE THIN-FILMS [J].
AZIZAN, M ;
BAPTIST, R ;
TAN, TAN ;
VEUILLEN, JY .
APPLIED SURFACE SCIENCE, 1989, 38 (1-4) :117-124
[3]  
BATTACHARYYA BK, 1986, PHYS REV B, V33, P3947
[4]   LOCALIZED EPITAXIAL-GROWTH OF RESI2 ON (111) AND (001) SILICON [J].
CHU, JJ ;
CHEN, LJ ;
TU, KN .
JOURNAL OF APPLIED PHYSICS, 1987, 62 (02) :461-465
[5]   SEMICONDUCTING SILICIDE SILICON HETEROSTRUCTURES - GROWTH, PROPERTIES AND APPLICATIONS [J].
DERRIEN, J ;
CHEVRIER, J ;
LETHANH, V ;
MAHAN, JE .
APPLIED SURFACE SCIENCE, 1992, 56-8 :382-393
[6]   LOW-TEMPERATURE SURFACE CLEANING OF SILICON AND ITS APPLICATION TO SILICON MBE [J].
ISHIZAKA, A ;
SHIRAKI, Y .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1986, 133 (04) :666-671
[7]  
ITOH S, 1990, 20TH P INT C PHYS SE, V1, P135
[8]   CHARACTERIZATION OF SI-28+ AND AR-40+ ION-IMPLANTED EPITAXIAL RESI2 FILMS ON AN N-SI(100) SUBSTRATE [J].
KIM, KH ;
KIM, DH ;
NAM, ST ;
LEE, JJ ;
KIM, IH ;
KIM, SC ;
LEE, JY ;
NICOLET, MA ;
BAI, G .
JOURNAL OF APPLIED PHYSICS, 1993, 74 (02) :1046-1050
[9]  
KRONTIRAS L, 1988, THIN SOLID FILMS, V161, P167
[10]   THE INFLUENCE OF GROWTH TECHNIQUES ON THE STRUCTURE OF EPITAXIAL ERSI1.7 ON SI(111) [J].
LOLLMAN, DBB ;
TAN, TAN ;
VEUILLEN, JY ;
MURET, P ;
LEFKI, K ;
BRUNEL, M ;
DUPUY, JC .
APPLIED SURFACE SCIENCE, 1993, 65-6 :704-711