Ni silicidation on heavily doped Si substrates

AbstractThe formation of TiSi2 from deposited Ti layers on Si and the subsequent transformation of TiSi 2 from the C49 to the C54 phase have long been of concern, particular for the silicide formation on heavily doped, narrow polycrystalline Si lines. In this work, phase formation during rapid thermal annealing of Ti/Mo bilayers sequentially deposited on blanket Si wafers and on narrow polycrystalline Si lines (0.6 μm width) is studied. The Mo layer is always 0.5 nm thick, and the Ti either 45 nm or 60 nm. It is shown that the initial physical separation of Ti from Si by the interposed Mo layer leads to complete prevention of the formation of the C49 phase. Instead, a Mo-bearing silicide phase of hexagonal structure forms first, and the C54 phase nucleates and then grows on top of it via Si diffusion through the growing silicide layers. The significance of this finding is that the usual sequence for the formation of TiSi2,. e. the C49 phase forms as a result of the Ti-Si interaction and the C54 phase forms as the product of phase transformation, is altered by the interposition of a thin refractory metal layer, here Mo. The difficulties involved in nucleation and growth of the C54 phase are then overcome, yet by a different approach than the usually employed ones which rely on ion implantation to enhance the formation of the C49 phase and the subsequent transformation to the C54 phase.

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Photoluminescence Studies of Annealed GaAs Films Grown on Si Substrates

MRS Proceedings ◽

10.1557/proc-116-233 ◽

1988 ◽

Vol 116 ◽

Cited By ~ 8

Author(s):

M. Bugajski ◽

K. Nauka ◽

S.J. Rosner ◽

D. Mars

Keyword(s):

High Temperature ◽

Low Temperature ◽

Free Carrier ◽

Apparent Difference ◽

High Temperature Annealing ◽

Si Substrates ◽

Gaas Films ◽

Excitonic Emission ◽

Heavily Doped ◽

Photoluminescence Studies

AbstractLow temperature (T - 5K) photoluminescence (PL) has been measured on a variety of as-grown and annealed GaAs films grown on Si substrates by the MBE technique. The PL spectra of the annealed GaAs layers showed an apparent difference between the nomigally undoped samples with free carrier concentrations below 1015 cm−3 and the layers with dopant concentrations exceeding 1017 atoms cm−3 . The annealing caused an increase of both excitonic and defect related PL intensities in low doped samples. In heavily doped layers the annealing suppressed excitonic emission and strongly enhanced defect related luminescence bands. Observed post annealed infrared shifts of the PL peaks in the excitonic region are explained assuming a tetragonally distorted GaAs lattice under tensile stress, and an increase in stress after high temperature annealing.

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Thermoelectric properties of Mg2 Si coatings deposited by pack cementation assisted process on heavily doped Si substrates

physica status solidi (a) ◽

10.1002/pssa.201300140 ◽

2014 ◽

Vol 211 (6) ◽

pp. 1308-1314 ◽

Cited By ~ 4

Author(s):

D. Stathokostopoulos ◽

E. C. Stefanaki ◽

M. Ioannou ◽

G. S. Polymeris ◽

D. Chaliampalias ◽

...

Keyword(s):

Thermoelectric Properties ◽

Pack Cementation ◽

Si Substrates ◽

Heavily Doped

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Thermal stability of Ni silicide films on heavily doped n+ and p+ Si substrates

Microelectronic Engineering ◽

10.1016/j.mee.2008.04.001 ◽

2008 ◽

Vol 85 (7) ◽

pp. 1642-1646 ◽

Cited By ~ 11

Author(s):

Parhat Ahmet ◽

Takashi Shiozawa ◽

Koji Nagahiro ◽

Takahiro Nagata ◽

Kuniyuki Kakushima ◽

...

Keyword(s):

Thermal Stability ◽

Si Substrates ◽

Heavily Doped ◽

Thermal Stability Of

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Sb Diffusion in Heavily Doped Si Substrates

Journal of The Electrochemical Society ◽

10.1149/1.1391610 ◽

1999 ◽

Vol 146 (1) ◽

pp. 336-338 ◽

Cited By ~ 1

Author(s):

Kunihiro Suzuki ◽

Hiroko Tashiro ◽

Takayuki Aoyama

Keyword(s):

Si Substrates ◽

Heavily Doped

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Defects in Heavily-Doped MBE GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054704 ◽

1982 ◽

Vol 40 ◽

pp. 442-445

Author(s):

C.B. Carter ◽

D.M. DeSimone ◽

T. Griem ◽

C.E.C. Wood

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Heavily Doped

Molecular-beam epitaxy (MBE) is potentially an extremely valuable tool for growing III-V compounds. The value of the technique results partly from the ease with which controlled layers of precisely determined composition can be grown, and partly from the ability that it provides for growing accurately doped layers.

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Interactions Between Al and Cr Thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093158 ◽

1976 ◽

Vol 34 ◽

pp. 638-639

Author(s):

R. M. Anderson ◽

T. M. Reith ◽

M. J. Sullivan ◽

E. K. Brandis

Keyword(s):

Thin Films ◽

Room Temperature ◽

Vacuum System ◽

Processing Temperature ◽

Diffusion Couples ◽

Electronic Circuits ◽

Intermetallic Formation ◽

Si Substrates ◽

Aluminum Silicon

Thin films of aluminum or aluminum-silicon can be used in conjunction with thin films of chromium in integrated electronic circuits. For some applications, these films exhibit undesirable reactions; in particular, intermetallic formation below 500 C must be inhibited or prevented. The Al films, being the principal current carriers in interconnective metal applications, are usually much thicker than the Cr; so one might expect Al-rich intermetallics to form when the processing temperature goes out of control. Unfortunately, the JCPDS and the literature do not contain enough data on the Al-rich phases CrAl7 and Cr2Al11, and the determination of these data was a secondary aim of this work.To define a matrix of Cr-Al diffusion couples, Cr-Al films were deposited with two sets of variables: Al or Al-Si, and broken vacuum or single pumpdown. All films were deposited on 2-1/4-inch thermally oxidized Si substrates. A 500-Å layer of Cr was deposited at 120 Å/min on substrates at room temperature, in a vacuum system that had been pumped to 2 x 10-6 Torr. Then, with or without vacuum break, a 1000-Å layer of Al or Al-Si was deposited at 35 Å/s, with the substrates still at room temperature.

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Electron Energy Analysis of Germanium and Silica Layers on Silicon Substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114104 ◽

1975 ◽

Vol 33 ◽

pp. 96-97

Author(s):

R. W. Ditchfield ◽

A. G. Cullis

Keyword(s):

Epitaxial Growth ◽

Electron Energy ◽

Silicon Substrates ◽

Secondary Phases ◽

Si Substrates ◽

Transmission Electron ◽

Layer Structures ◽

Si Films ◽

Electron Energy Loss ◽

Growth Centres

An energy analyzing transmission electron microscope of the Möllenstedt type was used to measure the electron energy loss spectra given by various layer structures to a spatial resolution of 100Å. The technique is an important, method of microanalysis and has been used to identify secondary phases in alloys and impurity particles incorporated into epitaxial Si films.Layers Formed by the Epitaxial Growth of Ge on Si Substrates Following studies of the epitaxial growth of Ge on (111) Si substrates by vacuum evaporation, it was important to investigate the possible mixing of these two elements in the grown layers. These layers consisted of separate growth centres which were often triangular and oriented in the same sense, as shown in Fig. 1.

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Defects in β-SiC thin films grown on α-SiC substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010490x ◽

1988 ◽

Vol 46 ◽

pp. 568-569

Author(s):

Karren L. More

Keyword(s):

Thin Films ◽

Semiconductor Device ◽

Lattice Mismatch ◽

Chemical Vapor ◽

Substrate Material ◽

Growth Interface ◽

Si Substrates ◽

Thermal Expansion Coefficients ◽

Device Applications ◽

Expansion Coefficients

Beta-SiC is an ideal candidate material for use in semiconductor device applications. Currently, monocrystalline β-SiC thin films are epitaxially grown on {100} Si substrates by chemical vapor deposition (CVD). These films, however, contain a high density of defects such as stacking faults, microtwins, and antiphase boundaries (APBs) as a result of the 20% lattice mismatch across the growth interface and an 8% difference in thermal expansion coefficients between Si and SiC. An ideal substrate material for the growth of β-SiC is α-SiC. Unfortunately, high purity, bulk α-SiC single crystals are very difficult to grow. The major source of SiC suitable for use as a substrate material is the random growth of {0001} 6H α-SiC crystals in an Acheson furnace used to make SiC grit for abrasive applications. To prepare clean, atomically smooth surfaces, the substrates are oxidized at 1473 K in flowing 02 for 1.5 h which removes ∽50 nm of the as-grown surface. The natural {0001} surface can terminate as either a Si (0001) layer or as a C (0001) layer.

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Electron microscope characterization of MOCVD-grown gap layers on Si

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144991 ◽

1986 ◽

Vol 44 ◽

pp. 724-725

Author(s):

K.M. Jones ◽

M.M. Al-Jassim ◽

J.M. Olson

Keyword(s):

Atmospheric Pressure ◽

Vapour Deposition ◽

Chemical Vapour ◽

Organic Chemical ◽

Lattice Match ◽

Si Substrates ◽

Metal Organic ◽

Good Lattice ◽

Antiphase Domains

The epitaxial growth of III-V semiconductors on Si for integrated optoelectronic applications is currently of great interest. GaP, with a lattice constant close to that of Si, is an attractive buffer between Si and, for example, GaAsP. In spite of the good lattice match, the growth of device quality GaP on Si is not without difficulty. The formation of antiphase domains, the difficulty in cleaning the Si substrates prior to growth, and the poor layer morphology are some of the problems encountered. In this work, the structural perfection of GaP layers was investigated as a function of several process variables including growth rate and temperature, and Si substrate orientation. The GaP layers were grown in an atmospheric pressure metal organic chemical vapour deposition (MOCVD) system using trimethylgallium and phosphine in H2. The Si substrates orientations used were (100), 2° off (100) towards (110), (111) and (211).

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