In situ x‐ray diffraction analysis of the C49–C54 titanium silicide phase transformation in narrow lines

ABSTRACTThe C54 phase formation process of titanium silicide was studied after selective chemical vapor despostion (CVD) onto very small silicon structures, to ascertain the efficacy of CVD to form low resistance contacts in sub-quarter micron technology. Because the selective CVD process forms silicide on any exposed silicon in a CMOS device, the process was studied on both polysilicon and Si (100) chips. The structures consisted of arrays of about 106 identical lines, 0.1 2.0 μm in width, depending on the chip. The CVD process employed TiCl4 and SiH4 for the most part as process gases and the depostion temperature ranged from 730–825°C. X-ray diffraction (XRD) was used to document the amount of C54 phase present after deposition. In some cases samples were annealed after deposition and the phase transformation behavior studied by in-situ XRD. The latter technique employed a synchrotron radiation source providng for rapid XRD spectra collection, so that the C49-C54 phase transformation could be examined with great precision in real time during rapid thermal annealing. The results of CVD depositions were compared to titanium silicide formed by sputter deposition of Ti on identical silicon chips, followed by a typical salicide protocol. Although the phase formation is affected by both film thickness and substrate temperature during CVD, the general result is that the C54 formation is more facile using the CVD process, especially for the smallest line dimensions. The findings are discussed with respect to nucleation processes occurring during growth and post-deposition thermal processing.

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In Situ Rapid Thermal Hydrogenation Pretreatment of Ti for Salicide RTA

MRS Proceedings ◽

10.1557/proc-429-187 ◽

1996 ◽

Vol 429 ◽

Author(s):

K. Ando ◽

T. Ishigami ◽

Y. Matsubara ◽

T. Horiuchi ◽

S. Nishimoto

Keyword(s):

Crystal Structure ◽

Phase Transition ◽

Diffraction Analysis ◽

Sheet Resistance ◽

Rapid Thermal Annealing ◽

Titanium Silicide ◽

Silicide Formation ◽

X Ray Diffraction ◽

X Ray

AbstractAn in situ rapid thermal hydrogenation (RTH) pretreatment of titanium prior to rapid thermal annealing (RTA), or RTH/RTA, is proposed as a silicide formation annealing in a CMOS self-aligned silicide (salicide) process. The in situ RTH is found to enhance silicidation, to reduce nitridation, and even to lower the resultant sheet resistance of titanium silicide.During in situ RTH (e.g., at 550°C), amorphous Ti silicide (e.g., 15-nm thick) grows selectively on Si. Furthermore, Ti nitridation during subsequent RTA (690°C, N2, 10 Torr, 30 s) is reduced depending on RTH (H2, 10 Torr, 30 s) temperature. Accordingly, for 550°C RTH and an initial Ti thickness of 15 nm, the sheet resistance obtained at the 0.27-μm-wide n+ poly-Si gate after a phase transition annealing (800°C, Ar, 10 s) was lower (11.7 Ω /□, st. dev. = 6%) than that of conventional Ti silicide (15.8 Ω/□, st. dev. = 10%). The silicidation enhancement and nitridation reduction are related to crystal structure metamorphosis or to hydrogen interstitial incorporation in the Ti layer during RTH as observed by x-ray diffraction analysis. It is concluded that in situ RTH pretreatment before RTA is very promising as a sub-quarter-micron CMOS salicide process.

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Is Selective Cvd an Improvement for the Titanium Silicide Process in Sub-Quarter Micron Technology? A Phase Formation Study Using X-Ray Diffraction

MRS Proceedings ◽

10.1557/proc-514-439 ◽

1998 ◽

Vol 514 ◽

Cited By ~ 1

Author(s):

Ronnen Roy ◽

Cryil Cabral ◽

Christian Lavoie ◽

Jean Jordan-Sweet ◽

R. Viswanathan ◽

...

Keyword(s):

Phase Transformation ◽

Phase Formation ◽

Chemical Vapor ◽

Titanium Silicide ◽

X Ray Diffraction ◽

X Ray ◽

Silicon Chips ◽

In Situ Xrd ◽

Silicon Structures

ABSTRACTThe C54 phase formation process of titanium silicide was studied after selective chemical vapor despostion (CVD) onto very small silicon structures, to ascertain the efficacy of CVD to form low resistance contacts in sub-quarter micron technology. Because the selective CVD process forms silicide on any exposed silicon in a CMOS device, the process was studied on both polysilicon and Si (100) chips. The structures consisted of arrays of about 106 identical lines, 0.1 2.0 μm in width, depending on the chip. The CVD process employed TiCl4 and SiH4 for the most part as process gases and the depostion temperature ranged from 730–825°C. X-ray diffraction (XRD) was used to document the amount of C54 phase present after deposition. In some cases samples were annealed after deposition and the phase transformation behavior studied by in-situ XRD. The latter technique employed a synchrotron radiation source providng for rapid XRD spectra collection, so that the C49-C54 phase transformation could be examined with great precision in real time during rapid thermal annealing. The results of CVD depositions were compared to titanium silicide formed by sputter deposition of Ti on identical silicon chips, followed by a typical salicide protocol. Although the phase formation is affected by both film thickness and substrate temperature during CVD, the general result is that the C54 formation is more facile using the CVD process, especially for the smallest line dimensions. The findings are discussed with respect to nucleation processes occurring during growth and post-deposition thermal processing.

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Insertion of Phosphenium Ions into a Bicyclo[1.1.0]Tetraphosphabutane Iron Complex

Molecules ◽

10.3390/molecules26133920 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3920

Author(s):

Martin Weber ◽

Gábor Balázs ◽

Alexander V. Virovets ◽

Eugenia Peresypkina ◽

Manfred Scheer

Keyword(s):

Diffraction Analysis ◽

Room Temperature ◽

31P Nmr ◽

Spectroscopic Studies ◽

Iron Complex ◽

The Novel ◽

X Ray Diffraction ◽

X Ray ◽

Phosphenium Ions

By reacting [{Cp‴Fe(CO)2}2(µ,η1:1-P4)] (1) with in situ generated phosphenium ions [Ph2P][A] ([A]− = [OTf]− = [O3SCF3]−, [PF6]−), a mixture of two main products of the composition [{Cp‴Fe(CO)2}2(µ,η1:1-P5(C6H5)2)][PF6] (2a and 3a) could be identified by extensive 31P NMR spectroscopic studies at 193 K. Compound 3a was also characterized by X-ray diffraction analysis, showing the rarely observed bicyclo[2.1.0]pentaphosphapentane unit. At room temperature, the novel compound [{Cp‴Fe}(µ,η4:1-P5Ph2){Cp‴(CO)2Fe}][PF6] (4) is formed by decarbonylation. Reacting 1 with in situ generated diphenyl arsenium ions gives short-lived intermediates at 193 K which disproportionate at room temperature into tetraphenyldiarsine and [{Cp‴Fe(CO)2}4(µ4,η1:1:1:1-P8)][OTf]2 (5) containing a tetracyclo[3.3.0.02,7.03,6]octaphosphaoctane ligand.

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Stress induced phase transformation in Ti60Cu14Ni12Sn4Ta10 nanostructure dendrite composite: In situ high-energy X-ray diffraction study

Materials Letters ◽

10.1016/j.matlet.2016.09.008 ◽

2016 ◽

Vol 185 ◽

pp. 376-379 ◽

Cited By ~ 1

Author(s):

T. Wang ◽

Q.G. Xie ◽

Y.D. Wu ◽

J.J. Si ◽

X.D. Hui ◽

...

Keyword(s):

Phase Transformation ◽

Diffraction Study ◽

High Energy ◽

X Ray Diffraction ◽

X Ray

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In Situ Stress Tensor Determination during Phase Transformation of a Metal Matrix Composite by High-Energy X-ray Diffraction

Materials ◽

10.3390/ma11081415 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1415 ◽

Cited By ~ 4

Author(s):

Guillaume Geandier ◽

Lilian Vautrot ◽

Benoît Denand ◽

Sabine Denis

Keyword(s):

Phase Transformation ◽

Stress Tensor ◽

Metal Matrix Composite ◽

Matrix Composite ◽

Metal Matrix ◽

High Energy ◽

X Ray Diffraction ◽

Synchrotron Source ◽

X Ray

In situ high-energy X-ray diffraction using a synchrotron source performed on a steel metal matrix composite reinforced by TiC allows the evolutions of internal stresses during cooling to be followed thanks to the development of a new original experimental device (a transportable radiation furnace with controlled rotation of the specimen). Using the device on a high-energy beamline during in situ thermal treatment, we were able to extract the evolution of the stress tensor components in all phases: austenite, TiC, and even during the martensitic phase transformation of the matrix.

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