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Electron energy loss spectroscopy studies of the amorphous to crystalline transition in FeF3 were conducted. The time-resolved studies reveal that the coordination polyhedra in amorphous FeF3 were randomly arranged FeF6 octahedra which are retained in amorphous FeF3. The change in the d-band occupancy by one electron and the sensitivity of the ratio of Fe L3 and L2 edges to the charge state of the iron ion are clearly illustrated using electron energy loss spectroscopy.

The impact of extended heat treatment on the metal induced lateral crystallization (MILC) rate of amorphous silicon (a-Si) is studied using transmission electron microscopy and orientation image microscopy. Results show that extended heat treatment reduces the MILC rate possibly due to the constantly changing state of the a-Si and decreasing Ni from the Ni covered area. MILC length also increased with the radii of the Ni disc patterns with the longest MILC lengths generated by straight-edged Ni patterns due to their infinite radii of curvature.

Nickel induced crystallization of amorphous silicon (a-Si) was investigated by selective deposition of Ni on a-Si thin films. The a-Si below and adjacent to the Ni-covered regions were observed to be crystallized after heat treatment at 500 deg C from 1 to 90 hrs. A substantial amount of Ni remained in the region under the original Ni coverage. The crystallized film below the Ni coverage was made up of randomly oriented fine grains while those outside the Ni coverage mainly consisted of large (110)-oriented grains.

The crystallization of amorphous selenium films was conducted by exposing them to simultaneous irradiation of a 488.0 nm line of Ar+ and a 676.4 nm line of a Kr+ laser by cross-band-gap and sub-band-gap light irradiation. It was observed that the crystallized amorphous selenium films displayed Raman spectra similar to that of trigonal crystalline. Results indicate that the crystallization process is delayed when the material is expose to both of the sources simultaneously.

A study was conducted on the vertical crystallization rates of various types of amorphous Si: implantation-amorphized bulk-crystal Si substrates, implantation-amorphized crystal Si layers epitaxially grown by ultrahigh vacuum CVD on bulk-crystal Si substrates, and amorphous layers directly deposited on bulk-crystal Si substrates by low-pressure CVD. The results suggest a close relationship between the mechanism of low-temperature crystallization of amorphous Si containing hydrogen atoms in polyhydride states and the mechanism of ion-beam-induced epitaxial crystallization.

The solid phase crystallization of amorphous silicon films using microwave heating was investigated. The amorphous silicon thin films were deposited in the temperature range of 100-400 degrees C by plasma enhanced chemical vapor deposition and annealed by microwave heating at 550 degrees C in nitrogen. Results indicate that microwave heating lowered the annealing temperature and reduced the annealing time for complete crystallization. Other observations are discussed.

In situ thermal pulse annealing of amorphous substrate to effect amorphous-germanium thin film phase transformation showed a film microstructure dependent on annealing ambient and exposure time. Air annealing showed hillock growth mode, while vacuum annealing produced a shift from microgranular to dendritic grain growth. The results indicate the possibility of Ge film presence in supercooled semiconductive liquid condition prior to crystallization.

Segregation and trapping of Er during solid-phase crystallization of amorphous Si on crystalline Si were investigated. Amorphous surface layers were prepared on Si(100) by 250 keV Er ion implantation, recrystallized at 600 degrees C and then studied by high-resolution Rutherford backscattering spectrometry. The segregation coefficient k was strongly affected by Er concentration. Results were in agreement with a model in which it is assumed that defects in the a-Si near the interface function as traps for the Er.

An amorphous Ge-Au(a-Ge-Au) film produced by vacuum deposition was examined in situ and irradiated by an electron beam in a transmission electron microscope. The amorphous Ge-Au film can be crystallized rapidly and locally by electron beam irradiation, forming polycrystalline metastable Ge0.4Aug0.6 tetragonal phase and then decomposing to polycrystalline Ge and polycrystalline Au at increased irradiation dose. Findings showed that the crystallization of a-GeAu film, the formation of Ge0.4Aug0.6 and the decomposition of the metastable Ge0.4Au0.6 are dependent on the temperature of the irradiation process.

Impurity-mediated crystallization dynamics occur in amorphous Ge films deposited on Si(iii):7 by 7 substrates. The dynamic processes generate non-dimensional strips of crystalline Ge. These one-dimensional stripes are oriented epitaxially on the substrates. A few of the stripes are epitaxially oriented on the buried reconstruction. The few strips provide a two dimensional feature to the substrates. The defects in the crystallization region and in the buried surface react with each other and retard further crystallization.

Amorphous CoSi2 is studied to determine the effect of ion beam irradiation on crystalline kinetics of amorphous CoSi2. Three dimensional growth of existing nuclei influences the crystallization kinetics of as-deposited CoSi2. The existing nuclei is amorphized by ion beam irradiation of as-deposited CoSi2. Direct amorphization is caused by heavy-ion irradiation. Variation in the growth mode from three-dimensional to two-dimensional decreases the density of preexisting nuclei.

The concentration of As doped into a-Si:H films increases with the increase of the crystallization temperatures of a-Si:H deposited on GaAs substrates by glow-discharge method. Crystallization of the a-Si:H films with a large concentration of As increases the temperature to 1050 degrees centigrade. Large quantities of H and SiH3 are found in these a-Si:H films.

A study was conducted to show that the crystallization temperature of Ni/a-Si can be minimized to 380 degrees C during the presence of an electric field. Raman spectroscopy was carried out to determine the structural and electrical features of the nickel-metal induced crystallization poly-silicon films. Results indicated that the structure of the poly-silicon crystallized in an electric field correlated with the thickness of the nickel layer on the a-Si.