Ion Mixing During Film Deposition: Growth of Metastable Semiconducting and Metallic Alloys

MRS Proceedings ◽

10.1557/proc-7-93 ◽

1981 ◽

Vol 7 ◽

Cited By ~ 1

Author(s):

K.C. Cadien ◽

M.A. Ray ◽

S.M. Shin ◽

J.M. Rigsbee ◽

S.A. Barnett ◽

...

Keyword(s):

Activation Barrier ◽

Essential Feature ◽

Rf Sputtering ◽

Ion Bombardment ◽

Film Deposition ◽

Low Energy ◽

Diffusion Annealing ◽

Transformation Rate ◽

High Temperature Stability ◽

Two Phase

ABSTRACTEpitaxial metastable (GaSb)1−Gex alloys with compositions across the pseudobinary phase diagram have been grown on (100) GaAs substrates by multitarget rf sputtering. An essential feature allowing the growth of these unique materials was low energy ion bombardment of the growing film during deposition to promote collisional mixing and enhance adatom diffusion. Annealing experiments indicated that the metastable films exhibit good high temperature stability. While the free energy difference between the single phase metastable and two phase equilibrium states is only ∼ 20 meV/atom, the activation barrier for the transformation is ∼ 3 eV. All films were ptype with room temperature carrier concentrations and mobilities between 1016 and 1019 cm−3 and 10 and 720 cm2/V∼sec, respectively, depending on film composition. Collisional mixing due to low energy ion bombardment of the growing film was also found to affect both the transformation rate kinetics as well as the reaction path during subsequent annealing of amorphous GaSb/Ge mixtures deposited on glass at 60°C. Finally, some initial results on the deposition of metastable fcc Cu/Cr alloys are presented.

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The Role of Low-Energy Ion/Surface Interactions During Crystal Growth From the Vapor Phase

MRS Proceedings ◽

10.1557/proc-74-59 ◽

1986 ◽

Vol 74 ◽

Cited By ~ 1

Author(s):

J. E. Greene ◽

A. Rockett ◽

J.-E. Sundgren

Keyword(s):

Surface Segregation ◽

Ion Irradiation ◽

Ion Bombardment ◽

Thin Film Deposition ◽

Film Deposition ◽

Low Energy ◽

Nucleation Kinetics ◽

Wear Resistant Coatings ◽

Average Grain Size

AbstractLow-energy (often < 100 eV) ion bombardment during thin film deposition is commonly used in such diverse application areas as microelectronics, optical coatings. magnetic recording layers. and hard wear resistant coatings to modify the microstructure and microchemistry of films deposited by a variety of techniques (e.g. sputtering, primary ion deposition, plasma-assisted CVD, and accelerated-beam MBE). Ion irradiation has been shown to affect every phase of deposition including nucleation and growth kinetics, crystal structure and phase stability, the average grain size and degree of preferred orientation of polycrystalline films, the epitaxial temperature of single-crystal films, defect concentrations, elemental incorporation probabilities, surface segregation, and, hence, film properties. As discussed in this brief review, a detailed understanding of many of these processes is beginning to emerge. Effects such as trapping, preferential sputtering, enhanced diffusion, and collisional mixing have been used to interpret and, in some cases, model experimental results. Nevertheless, there are still large gaps in our knowledge of the role of ion bombardment on fundamental processes such as nucleation kinetics.

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The Role of Low-Energy Ion/Surface Interactions During Crystal Growth From the Vapor Phase

MRS Proceedings ◽

10.1557/proc-75-39 ◽

1986 ◽

Vol 75 ◽

Cited By ~ 3

Author(s):

J. E. Greene ◽

A. Rocketr ◽

J.-E. Sundgren

Keyword(s):

Surface Segregation ◽

Ion Irradiation ◽

Ion Bombardment ◽

Thin Film Deposition ◽

Film Deposition ◽

Low Energy ◽

Nucleation Kinetics ◽

Wear Resistant Coatings ◽

Average Grain Size

AbstractLow-energy (often < 100 eV) ion bombardment during thin film deposition is commonly used in such diverse application areas as microelectronics, optical coatings, magnetic recording layers, and hard wear resistant coatings to modify the microstructure and microchemistry of films deposited by a variety of techniques (e.g. sputtering, primary ion deposition, plasma-assisted CVD. and accelerated-beam MBE). Ion irradiation has been shown to affect every phase of deposition including nucleation and growth kinetics, crystal structure and phase stability, the average grain size and degree of preferred orientation of polycrystalline films, the epitaxial temperature of single-crystal films, defect concentrations, elemental incorporation probabilities, surface segregation, and, hence, film properties. As discussed in this brief review, a detailed understanding of many of these processes is beginning to emerge. Effects such as trapping, preferential sputtering, enhanced diffusion, and collisional mixing have been used to interpret and, in some cases, model experimental results. Nevertheless, there are still large gaps in our knowledge of the role of ion bombardment on fundamental processes such as nucleation kinetics.

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