In the past, we
have used optical emission spectroscopy, optical time-of-fligt (TOF), UV
target reflectivity measurements and ion-mass spectrometry during PLAD
of various ceramic and metal targets.
More recently,
we have developed a system, based on absorption spectroscopy of atomic
and molecular oxygen, able to investigate in the details the modifications
of the molecular oxygen environment used during deposition of ceramic materials.
Information that can be obtained through this diagnostics span over time-
and space-resolved mapping of atomic oxygen produced following dissociation
of the environment gas, gas temperature derived by absoprtion line profiles,
occurrence of shock-waves during plume expansion, presence of different
reactive-collisional mechanisms involving ablated species, environment
gas, and electrons produced during PLAD.
Here following is a table where the
most relevant results obtained with those techniques are summarized.
Since from
the early beginning of our work with PLAD, we have been interested in investigating
the basic physical phenomena involved in the process, with the twofold aim of controlling
the deposition process and unraveling the role of the deposition
parameters.
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Modifications of plume composition during its expansion | Occurrence of reactive-collisional processes and formation of oxidized molecules |
| G. Masciarelli,
F. Fuso, M. Allegrini and E. Arimondo, "Observation of metal oxide bands
in the plume of photoablated superconductive materials", J. Mol. Spectrosc.
153 96 (1992).
B. H. Feng, G. Masciarelli, F. Fuso, M. Allegrini and E. Arimondo, "Laser deposition of high Tc superconductive thin films and plume diagnostic from in-situ fluorescence", pag. 777 in High Temperature Superconductors (BHTSC '92), Z. X. Zhao, Z. Z. Gan and S. S. Xie Editors., World Scientific, Singapore, 1993. |
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| Optical Time-Of-Flight | Expansion velocity and translational temperature of ablated materials | |
| F. Fuso, G. Masciarelli, M. Allegrini, F. Lazzeri and E. Arimondo, "Pulsed laser deposition of thin films and in-situ diagnostics of the process", p. 43 in "Advances in Inorganic Films and Coatings", P. Vincenzini Ed. (Techna, Faenza. 1995). | ||
| Stark broadening of emission lines and presence of plasma continuum emission | Characterization of the plasma created by PLAD (ne and Te) | |
| F.
Fuso, L.N. Vyacheslavov, G. Masciarelli, and E. Arimondo, "Stark
broadening diagnostics of the electron density in pulsed laser ablation
of YBCO and PZT ", J. Appl. Phys.
76 8088 (1994).
M. Allegrini, F. Fuso, G. Lorenzi, L.N. Vyacheslavov, and E. Arimondo, " Spectroscopy as in-situ diagnostics for pulsed laser deposition of superconductive and ferroelectric thin films", Appl. Surf. Sci. 106 438 (1996). ) A. Camposeo, F. Cervelli, F. Fuso, M. Allegrini and E. Arimondo, ÒMechanisms for O2 dissociation during pulsed-laser ablation and depositionÓ, Appl. Phys. Lett. 76 2402 (2001). |
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| Time-resolved UV reflectivity of the target | Absorption of UV radiation by the plasma created following laser-matter interaction | |
| F. Fuso, L. Vyacheslavov, G. Lorenzi, M. Allegrini and E. Arimondo, "Optical Diagnostics of the Laser-Target and Laser-Plume Interaction in Pulsed Laser Ablation", Appl. Surf. Sci. 96/98 181 (1996). | ||
| Time- and space-resolved oxygen absorption spectroscopy | Absorption by O and O2 | |
| F.
Cervelli, F. Fuso, M. Allegrini,
and E. Arimondo, "In-situ diagnostics of pulsed laser ablation through atomic oxygen
absorption spectroscopy", Appl. Surf. Sci. 127/129 679 (1998).
A. Camposeo, F. Cervelli, F. Fuso, M. Allegrini and E. Arimondo, "Analysis of plume-buffer gas interactions through molecular and atomic oxygen absorption", Appl. Phys. A 69 S509 (1999). A. Camposeo, F. Cervelli, F. Fuso, M. Allegrini and E. Arimondo, ÒMechanisms for O2 dissociation during pulsed-laser ablation and depositionÓ, Appl. Phys. Lett. 76 2402 (2001). |
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| Ion-mass spectrometry | Modifications of plume composition during its expansion (ionized fraction) | Formation of clusters and doping of C60 |
| A.
Iembo, F. Fuso, M. Allegrini, E. Arimondo, V. Berardi, N. Spinelli, F.
Leccabue, B. E. Watts, G. Franco and G. Chiorboli, "In-situ diagnostics
of pulsed laser deposition of ferroelectric Pb(Ti0.48 Zr0.52)O3
on Si", Appl. Phys. Lett. 63 1194 (1993).
M. Allegrini, E. Arimondo, C. Callegari, F. Fuso, A. Iembo, G. Masciarelli, V. Berardi, N. Spinelli, S. Rossini and R. Danieli, "Laser Ablation and Deposition of Graphite, Lanthanum and Lanthanum-Doped Fullerene", pag. 31 in Fullerene Status and Perspectives, C. Taliani, G. Ruani, and R. Zamboni Editors (World Scientific, Singapore, 1992). E. Arimondo, F. Calderazzo, G. Masciarelli, C. Toffi and F. Fuso, "Carbon Laser Vaporization in the Presence of Carbon Dioxide", Appl. Phys. A 66 407 (1998). |
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| Statistical analysis of TOFMS data on a shot-to-shot basis | Identification of main reactive channels leading to formation of clusters | |
| V.
Berardi, N. Spinelli, R. Velotta, M. Armenante, F. Fuso, M. Allegrini and
E. Arimondo, "Correlation analysis of laser ablated ions from YBCO",
Phys. Lett. A 179 116 (1993).
V. Berardi, S. Amoruso, N. Spinelli, R. Velotta, F. Fuso, M. Allegrini and E. Arimondo, "Diagnostics of YBCO laser plume by Time of Flight Mass Spectrometry", J. Appl. Phys. 76 8077 (1994). S. Amoruso, V. Berardi, N. Spinelli, A. Dente, M. Armenante, R. Velotta, F. Fuso, M. Allegrini and E. Arimondo, "Laser Ablation of PZT Target: Characterization and Evolution of Charged Species", J. Appl. Phys. 78 494 (1995). A. Camposeo, F. Fuso, E. Arimondo, and A. Tuissi, " Pulsed laser deposition and in--situ diagnostics of the process applied to shape memory alloys ", Appl. Phys. A, in press (2002). |
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Presently, our efforts are devoted mostly to: