Phase Formation and Kinetic Processes in Silicide Growth.

1983 ◽  
Vol 25 ◽  
Author(s):  
G. Ottaviani
Keyword(s):  
Boundary Conditions ◽  
Phase Formation ◽  
Growth Kinetics ◽  
Metal Layer ◽  
Silicide Phase ◽  
Reaction Products ◽  
Silicon Structures ◽  
Silicide Growth ◽  
Kinetic Processes ◽  
Kinetics Of

ABSTRACTTwenty years of research have now been devoted to investigating reaction products obtained by annealing metal-layer/silicon structures. A wide variety of cases have been analyzsed and a considerable amount of data has been produced. Despite the vast amount of information available, several aspects concerning phase formation and kinetic processes are not yet well established. The purpose of this paper is to investigate the mechanisms of phase formation and to show the importance of kinetic factors in the appearance of various compounds. Results will be shown for a single metal layer deposited on silicon, for bilayers. and for alloys. Depending upon the starting structure, metal-rich or silicon-rich silicides can be formed. Moreover, by modifying the boundary conditions, it is possible to change the growth kinetics of the silicide phase that forms.

Silicon Transport in Lateral Silicide Growth of CrSi2

1986 ◽  
Vol 71 ◽  
Author(s):  
L. R. Zheng ◽  
L. R. Doolittle ◽  
J. W. Mayer
Keyword(s):  
Growth Kinetics ◽  
Lateral Diffusion ◽  
Diffusion Couples ◽  
Si Substrates ◽  
Impurity Segregation ◽  
Silicide Growth ◽  
Device Geometry ◽  
Metal Layers ◽  
Kinetics Of ◽  
Influence Of Impurities

AbstractSilicide formation and growth are studied in three geometries: conventional planar thin films, lateral diffusion couples formed by depositing metal layers on Si islands, and device geometry couples formed by depositing metal on oxide-patterned Si substrates. The influence of impurities is studied by implanting arsenic and krypton into conventional and device geometry structures.Here we present growth kinetics of CrSi2 where the presence of impurities has a strong influence. Si transport dominates in disilicide formation and leads to erosion of contacts around the periphery of oxide windows. Implantation of arsenic suppresses CrSi 2 formation; with krypton implantation, the growth kinetics shifts from linear to square-root in character. We attribute these results to impurity segregation at interfaces or grain boundaries.

Interdiffusion and Phase Formation During Thermal Annealing of Ti/Mo Bilayers on Si Substrates

1996 ◽  
Vol 427 ◽  
Author(s):  
A. Mouroux ◽  
S.-L. Zhang ◽  
W. Kaplan ◽  
S. Nygren ◽  
M. Östling ◽  
...  
Keyword(s):  
Thermal Annealing ◽  
Phase Formation ◽  
Metal Layer ◽  
Hexagonal Structure ◽  
Silicide Phase ◽  
Silicide Formation ◽  
Physical Separation ◽  
Subsequent Transformation ◽  
Si Substrates ◽  
Heavily Doped

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.

In-Situ resistance Measurements During Rapid Thermal Annealing for Process Characterization

1995 ◽  
Vol 387 ◽  
Author(s):  
E. G. Colgan ◽  
C. Cabral ◽  
L. A. Clevenger ◽  
J. M. E. Harper
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Silicide Phase ◽  
Heating Rates ◽  
Process Characterization ◽  
Process Learning ◽  
Silicon Structures ◽  
The Stability ◽  
Kinetics Of

AbstractMeasurement of resistance in-situ during rapid thermal annealing is a powerful technique for process characterization and optimization. A major advantage of in-situ resistance measurements is the very rapid process learning. With silicides, in-situ resistance measurements can quickly determine an appropriate thermal process in which a low resistance silicide phase is formed without the agglomeration or inversion of silicide/polycrystalline silicon structures. One example is an optimized two step anneal for CoSi2 formation which was developed in less than one day. Examples of process characterization include determining the phase formation kinetics of TiSi2 (C49 and C54), Co2Si, and CoSi2 using in-situ ramped resistance measurements. The stability of TiSi2 or CoSi2/poly-Si structures has also been characterized by isothermal measurements. Resistance measurements have been made at heating rates from 1 to 100°C/s and temperatures up to 1000°C. The sample temperature was calibrated by melting Ag, Al, or Au/Si eutectics.

In-Situ Resistance Measurements During Rapid Thermal Annealing for Process Characterization

1995 ◽  
Vol 389 ◽  
Author(s):  
E.G. Colgan ◽  
C. Cabral ◽  
L.A. Clevenger ◽  
J.M.E. Harper
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Silicide Phase ◽  
Heating Rates ◽  
Process Characterization ◽  
Process Learning ◽  
Silicon Structures ◽  
The Stability ◽  
Kinetics Of

ABSTRACTMeasurement of resistance in-situ during rapid thermal annealing is a powerful technique for process characterization and optimization. A major advantage of in-situ resistance measurements is the very rapid process learning. With silicides, in-situ resistance measurements can quickly determine an appropriate thermal process in which a low resistance silicide phase is formed without the agglomeration or inversion of silicide/polycrystalline silicon structures. One example is an optimized two step anneal for CoSi2 formation which was developed in less than one clay. Examples of process characterization include determining the phase formation kinetics of TiSi2 (C49 and C54), Co2Si, and CoSi2 using in-situ ramped resistance measurements. The stability of TiSi2 or CoSi2/poly-Si structures has also been characterized by isothermal measurements. Resistance measurements have been made at heating rates from 1 to 100°C/s and temperatures up to 1000°C. The sample temperature was calibrated by melting Ag, Al, or Au/Si eutectics.

Kinetics of Interfacial Reaction in SiCf/Ti6Al4V Composites

2007 ◽  
Vol 546-549 ◽  
pp. 1627-1632 ◽  
Author(s):  
Yan Qing Yang ◽  
X.H. Lu ◽  
X. Luo ◽  
Z.J. Ma ◽  
J.K. Li ◽  
...  
Keyword(s):  
Interfacial Reaction ◽  
Reaction Zone ◽  
Growth Kinetics ◽  
Diffusion Theory ◽  
Element Distribution ◽  
Reaction Products ◽  
Sic Fiber ◽  
Diffusion Controlled ◽  
Kinetics Of

The Ti6Al4V composites reinforced with Chinese SiC fiber was manufactured and then thermally exposed at 800°C, 900°C and 1000°C, respectively, for up to 500h. The interfacial reaction products were identified as TiC between Ti6Al4V and the C-coating of the SiC fiber. However, if the SiC fiber has no C-coating, the interfacial reaction forms TiC, Ti3SiC2, Ti5Si3(Cx) and Ti3Si(Cx). The thickness of the interfacial reaction zone was measured and it is found that the thickening rate is slower in the samples in which the SiC fiber has the C-coating. The growth of the interfacial reaction products is diffusion-controlled and the parameters of the growth kinetics, k0 and Q, were determined, respectively. The profile of the element distribution was calculated according to the diffusion theory and is well consistent with the expeimental data.

Kinetics of formation of silicides: A review

1986 ◽  
Vol 1 (1) ◽  
pp. 205-221 ◽  
Author(s):  
F. M. d'Heurle ◽  
P. Gas
Keyword(s):  
Phase Formation ◽  
Reaction Rate ◽  
Diffusion Control ◽  
Specific Effects ◽  
Diffusion Controlled ◽  
Kinetics Of Formation ◽  
Amorphous Compounds ◽  
Silicide Growth ◽  
Rate Controlled ◽  
Kinetics Of

The kinetics of silicide growth are classified into three different categories: (a) diffusion controlled, (b) nucleation controlled, (c) others (reaction rate controlled). These are analyzed with the aim of understanding both the phenomenology of growth and the specific atomic mechanisms of phase formation. Diffusion-controlled growth is discussed with respect to the Nernst-Einstein equation. Stress relaxation is considered as a possible cause of reaction-rate control. The relative merits of two different types of marker experiments are compared. A few silicides are discussed in terms of what can be inferred about diffusion mechanisms. The competition between reaction-rate and diffusion control phenomena is shown to have specific effects on the sequence of phase formation; it is also related to the formation of some amorphous compounds. Reactions between silicon and alloyed metal films are used to illustrate the respective influences of mobility and driving force factors on the kinetics of silicide growth; they can also be used to underline the dominance of nucleation over diffusion in some silicide formation processes.

The Ordered Phase Formation in Ti-Al-Ga Alloys

1970 ◽  
Vol 28 ◽  
pp. 440-441
Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Titanium Alloys ◽  
Growth Kinetics ◽  
Stoichiometric Composition ◽  
Good Potential ◽  
Alpha Titanium ◽  
Cold Rolled ◽  
Kinetics Of ◽  
Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

The Kinetics of Inhibition of the Action of Thrombin by the Fibrinopeptides Formed during the Clotting of Fibrinogen

1966 ◽  
Vol 16 (01/02) ◽  
pp. 277-295 ◽  
Author(s):  
A Silver ◽  
M Murray
Keyword(s):  
Amino Acids ◽  
Competitive Inhibition ◽  
Amorphous Material ◽  
Peptide Bond ◽  
Initial Reaction ◽  
Reaction Products ◽  
Coagulation Mechanism ◽  
Kinetics Of ◽  
Kinetics Of Inhibition ◽  
Burk Plot

SummaryVarious investigators have separated the coagulation products formed when fibrinogen is clotted with thrombin and identified fibrinopeptides A and B. Two other peaks are observed in the chromatogram of the products of coagulation, but these have mostly been dismissed by other workers. They have been identified by us as amino acids, smaller peptides and amorphous material (37). We have re-chromatographed these peaks and identified several amino acids. In a closed system of fibrinogen and thrombin, the only reaction products should be fibrin and peptide A and peptide B. This reasoning has come about because thrombin has been reported to be specific for the glycyl-arginyl peptide bond. It is suggested that thrombin also breaks other peptide linkages and the Peptide A and Peptide B are attacked by thrombin to yield proteolytic products. Thrombin is therefore probably not specific for the glycyl-arginyl bond but will react on other linkages as well.If the aforementioned is correct then the fibrinopeptides A and B would cause an inhibition with the coagulation mechanism itself. We have shown that an inhibition does occur. We suggest that there is an autoinhibition to the clotting mechanism that might be a control mechanism in the human body.The experiment was designed for coagulation to occur under controlled conditions of temperature and time. Purified reactants were used. We assembled an apparatus to record visually the speed of the initial reaction, the rate of the reaction, and the density of the final clot formed after a specific time.The figures we derived made available to us data whereby we could calculate and plot the information to show the mechanism and suggest that such an inhibition does exist and also further suggest that it might be competitive.In order to prove true competitive inhibition it is necessary to fulfill the criteria of the Lineweaver-Burk plot. This has been done. We have also satisfied other criteria of Dixon (29) and Bergman (31) that suggest true competitive inhibition.

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