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A number of researchers have demonstrated the potential of a series of β-diketonate Cu(I) compounds, (β-diketonate)CuL n , where L is Lewis base and n = 1 or 2, that fulfill most of the criteria outlined for precursor design before. These species were chosen as copper precursors for the following reasons:

  • They contain the β-diketonate ligand which generally imparts volatility to metal-organic complexes, particularly when fluorinated, as a result of a reduction in hydrogen-bonding in the solid-state.
  • They are capable of systematic substitution through both the β-diketonate and Lewis base ligands to tailor volatility and reactivity.
  • Lewis bases such as phosphines, olefins and alkynes are unlikely to thermally decompose at temperatures where copper deposition occurs.
  • These precursors can deposit copper via thermally induced disproportionation reactions and no ligand decomposition is required since the volatile Lewis base the Cu(II) disproportionation products are transported out of the reactor intact at the disproportionation temperature.

Reaction mechanism

A general feature of the reactions of Cu(I) precursors is that they thermally disproportionate, a mechanism likely to be responsible for the high purity of the copper films observed since ligand decomposition does not occur. The disproportionation mechanism is shown in [link] for (β-diketonate)CuL. The unique capabilities of this class of compounds result from this reaction mechanism by which they deposit copper. This mechanism is based on the dissociative adsorption of the precursor to form Cu(hfac) and L, disproportionation to form Cu(hfac) 2 and Cu and desorption of Cu(hfac) 2 and L.

Schematic diagram of the disproportionation mechanism. Adapted from T. Kodas and M. Hampden-Smith, The Chemistry of Metal CVD , VCH Publishers Inc., New York, NY (1994).

Thus, the starting material acts as its own reducing agent and no external reducing agent such as H 2 is required. Another advantage of the Cu(I) β-diketonates over the Cu(II) β-diketonates is that in the former the ligand L can be varied systematically, allowing the synthesis of a whole series of different but closely related compounds.


Selectivity deposition has been studied in both hot- and cold-wall CVD reactors as a function of the nature of the substrate, the temperature of the substrate and the nature of the copper substituents. Selectivity has usually been evaluated by using Si substrates on which SiO 2 has been grown and patterned with various metals by either electron-beam deposition, CVD or sputtering. Research has suggested that selectivity on metallic surfaces is attributable to the biomolecular disproportionation reaction involved in precursor decomposition.


  • J. R. Creighton, and J. E. Parmeter, Critical Review in Solid State and Materials Science , 1993, 18 , 175.
  • L. H. Dubois and B. R. Zegarski, J. Electrochem. Soc. , 1992, 139 , 3295.
  • J. J. Jarvis, R. Pearce, and M. F. Lappert, J. Chem. Soc. , Dalton Trans. , 1977, 999.
  • A. E. Kaloyeros, A. Feng, J. Garhart, K. C. Brooks, S. K. Ghosh, A. N. Sazena, and F. Luehers, J. Electronic Mater., 1990, 19 , 271.
  • T. Kodas and M. Hampden-Smith, The Chemistry of Metal CVD , VCH Publishers Inc., New York, NY (1994).
  • C. F. Powell, J. H. Oxley, and J. M. Blocher Jr., Vapor Deposition , John Wiley, New York (1966).
  • S. Shingubara, Y. Nakasaki, and H. Kaneko, Appl. Phys. Lett., 1991, 58 , 42.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
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Adin Reply
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what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
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Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
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Source:  OpenStax, Chemistry of electronic materials. OpenStax CNX. Aug 09, 2011 Download for free at http://cnx.org/content/col10719/1.9
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