Melting and Solidification Dynamics in Zone Melting of Si Films.

1987 ◽  
Vol 107 ◽  
Author(s):  
D. Dutartre
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Zone Melting ◽  
Silicon On Insulator ◽  
Experimental Conditions ◽  
Melting Front ◽  
Physical Mechanisms ◽  
Si Films ◽  
Melting And Solidification

AbstractWe discuss the physics involved in the melting and solidification of Silicon On Insulator thin films (SOI) using lamp or graphite strip heaters. The melting front, called “explosive melting”, controls to a large part the final morphological quality of the SOI film. It exhibits instabilities which can (i) nucleate the dewetting of the film, (ii) cause voids, and (iii) produce a poor surface morphology. The morphologies of the solidification fronts are analyzed. We show that, depending on the experimental conditions, different physical mechanisms are responsible for the front breakdown. Thus we propose that the variety of front morphologies results from the variety of the mechanisms involved, and of their combinations with the “faceting effects”.

Microscopy of Thin Si Films During Lamp Zone Melting

1985 ◽  
Vol 53 ◽  
Author(s):  
D. Dutartre ◽  
M. Haond ◽  
D. Bensahel
Keyword(s):  
Zone Melting ◽  
Silicon On Insulator ◽  
Spatial Modulation ◽  
Freezing Front ◽  
Melting Front ◽  
Scan Speed ◽  
Entrainment Effect ◽  
Si Films ◽  
Melting And Solidification

ABSTRACTThe melting and solidification fronts of thin Silicon On Insulator (SOI) films have been observed in-situ. The melting front does not advance continuously but by bursts. This so called “explosive melting” allows to explain the appearance of defects (such as voids and surface roughness) observed in the recrystallized film. The freezing front is observed in the case where a pattern for the entrainment of the defects has been etched in the underlying oxide: we show that the entrainment effect is due to the spatial modulation of the solidification front by the structure. Furthermore, the scan speed influences the morphology of the liquid/solid interface and the defect entrainment efficiency.

Magnetic Anisotropy of Strained La0.7Sr0.3MnO3 Thin Films Studied by MOKE

2001 ◽  
Vol 690 ◽  
Author(s):  
M. Koubaa ◽  
A.M. Haghiri-Gosnet ◽  
P. Lecoeur ◽  
W. Prellier ◽  
B. Mercey
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Scaling Law ◽  
Hysteresis Loops ◽  
Magnetic Behavior ◽  
Growth Conditions ◽  
Structural Quality ◽  
Lattice Strains ◽  
Stress States

ABSTRACTThe effects of the growth conditions and the lattice strains of pulsed laser deposited (PLD) La0.7Sr0.3MnO3 (LSMO) thin films upon the magnetic behavior have been studied using magneto-optical Kerr effect (MOKE) at room temperature. First, the structural quality of the films was investigated by XRD and the surface morphology was studied using AFM. It is shown that both surface morphology and crystallinity are optimized when the target-to-substrate distance and the oxygen pressure are chosen in agreement with a PD3 scaling law. Secondly, hysteresis loops have been recorded along the [100], [110] and [001] directions and the easy directions of magnetization have been determined for both stress states, i.e. tension on SrTiO3 and compression on LaAlO3. In tensile films, the whole plane is found to be easy, whereas, in compressive films, the easy axis should be an intermediate direction between the film's plane and its normal. Moreover, tensile films deposited under optimized growth conditions exhibit the largest anisotropy coefficient (K1eff = -6.9×105 erg/cm3).

Recent Advances in Si And Ge Zone-Melting Recrystallization

1984 ◽  
Vol 35 ◽  
Author(s):  
C. K. Chen ◽  
M. W. Gels ◽  
H. K. Choi ◽  
B-Y. Tsaur ◽  
John C. C. Fan
Keyword(s):  
Zone Melting ◽  
Recent Advances ◽  
Si Films

ABSTRACTBy improving the thermal uniformity and stability of our graphite-strip-heater oven, we have been able to significantly improve the overall quality of ZMR Si films. We have observed unbranched subboundaries and new types of defects that are less extended than the usual sub-boundaries. The overall wafer flatness has been improved so that total warp is less than 4 μm for 3-inch wafers. We have also utilized the ZMR technique for producing thin Ge-on-insulator films.

Growth -Front Modulation in Lamp Zone Melting of Si on SiO2

1986 ◽  
Vol 74 ◽  
Author(s):  
D. Dutartre ◽  
D. Bensahel ◽  
M. Haond
Keyword(s):  
Solidification Front ◽  
Growth Front ◽  
Zone Melting ◽  
Silicon On Insulator ◽  
Polysilicon Film ◽  
Defect Localization ◽  
In Situ Observations ◽  
Periodical Variation

AbstractWe present 3 techniques of defect localization we have studied in order to produce Silicon On Insulator films obtained by Lamp Zone Melting. They consist in a periodical variation of the thickness of either the oxide cap, or the polysilicon film, or the underlying oxide layer. We compare the crystallographic quality of the resulting films and in-situ observations of the solidification front for each structure.

Silicon-On-Insulator Mosfets Fabricated in Zone-Melting-Recrystallized Poly-Si Films on SiO2

1981 ◽  
Vol 4 ◽  
Author(s):  
B­Y. Tsaur ◽  
M. W. Gels ◽  
John C. C. Fan ◽  
D. J. Silversmith ◽  
R. W. Mountain
Keyword(s):  
Carrier Mobility ◽  
High Surface ◽  
Zone Melting ◽  
Silicon On Insulator ◽  
Surface Electron ◽  
Leakage Currents ◽  
Si Substrates ◽  
Enhancement Mode ◽  
Low Leakage ◽  
Si Films

ABSTRACTN- and p-channel enhancement-mode MOSFETs have been fabricated in Si films prepared by zone-melting recrystallization of poly-Si deposited on SiO2-coated Si substrates. The transistors exhibit high surface mobilities, in the range of 560–620 cm2/V−s for electrons and 200–240 cm2/V−s for holes, and low leakage currents of the order of 0.1 pA/μm (channel width). Uniform device performance with a yield exceeding 90% has been measured in tests of more than 100 devices. The interface between the Si film and the SiO2 layer on the substrate is characterized by an oxide charge density of 1–2 × 1011 cm−2 and a high surface carrier mobility. N-channel MOSFETs fabricated inSi films recrystallized on SiO2-coated fused quartz subtrates exhibit surface electron mobilities substantially higher than those of single-crystal Si devices because the films are under a large tensile stress.

Capping Techniques for Zone-Melting-Recrystallized Si-On-Insulator Films

1985 ◽  
Vol 53 ◽  
Author(s):  
C.K. Chen ◽  
L. Pfeiffer ◽  
K.W. West ◽  
M.W. Gels ◽  
S. Darack ◽  
...  
Keyword(s):  
Crystallographic Texture ◽  
Auger Spectroscopy ◽  
Zone Melting ◽  
Silicon On Insulator ◽  
Capping Layer ◽  
Spectroscopy Studies ◽  
Si Films ◽  
Film Annealing

ABSTRACTTo prepare silicon-on-insulator (SOI) films by graphite-strip-heater zone-melting recrystallization (ZMR), a capping technique must be used to insure wetting by the molten Si zone. We have demonstrated two new capping techniques that result in reproducible wetting without degrading the crystallographic texture of the recrystallized film: annealing SiO2- capped Si films in NH3 and depositing two SiNx layers with carefully controlled compositions on the SiO2 capping layer. Wetting is promoted by the incorporation of trace amounts of nitrogen at the Si-SiO2 interface. Both N implantation experiments and Auger spectroscopy studies establish that the presence of less than a monolayer of nitrogen at this interface is sufficient to insure wetting.

Thermal Profiles in Silicon-On-Insulator (Sod Material Recrystallized With Scanning Light Line Sources

1984 ◽  
Vol 35 ◽  
Author(s):  
Katsuhiko Kubota ◽  
Charles E. Hunt ◽  
Jeffrey Frey
Keyword(s):  
Zone Melting ◽  
Silicon On Insulator ◽  
Source Zone ◽  
Two Dimensional ◽  
Phase Boundaries ◽  
Multilayered Structures ◽  
Experimental Conditions ◽  
Dimensional Solution ◽  
Solidification Model ◽  
Light Line

ABSTRACTA two dimensional solution of the classical heat equation is obtained and used to predict thermal profiles during line source zone melting recrystallization of silicon on insulators. A macroscopic solidification model is used to find the extent of the molten zone in multilayered structures. The problems of convergence associated with moving phase boundaries are reduced by using transformed temperature and the enthalpy model The resultant isotherms, obtained at varying zone scan speeds, indicate optimum experimental conditions.

Effect of Annealing Temperature on Two-Step Method of GaN Films

2012 ◽  
Vol 629 ◽  
pp. 9-13
Author(s):  
Mei Liu ◽  
Xue You Xu ◽  
Bao Yuan Man ◽  
De Min Kong
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Annealing Temperature ◽  
Laser Energy ◽  
Pulsed Laser ◽  
Nitrogen Atmosphere ◽  
Laser Source ◽  
Step Method ◽  
Experimental Conditions ◽  
Force Microscopy

GaN thin films have been deposited on Si (111) substrates by pulsed laser deposition (PLD) of a GaN target in nitrogen atmosphere. An Nd: YAG pulsed laser with a wavelength of 1064 nm was used as a laser source. The results indicate that the GaN thin films deposited only by PLD are amorphous. By annealing in an NH3 atmosphere, the quality of the GaN thin films is improved, and the crystallzinity GaN thin films were obtained. The influence of annealing temperature on the crystallinity, structure, surface morphology and optical properties of GaN films have been examined by X-ray diffraction (XRD), atomic force microscopy (AFM) and infrared spectrum. In our experimental conditions, the GaN thin films deposited by PLD with a laser energy of 250 mJ, growth temperature of 800 °C and annealed at 1000 °C have the best surface morphology and crystalline quality.

scholarly journals Microstructure of Pulsed-Laser Deposited Pzt on Polished and Annealed Mgo Substrates

1996 ◽  
Vol 433 ◽  
Author(s):  
Simon L. King ◽  
Luigi G. Coccia ◽  
J.G.E. Gardeniers ◽  
Ian W. Boyd
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Lead Zirconate Titanate ◽  
Pulsed Laser ◽  
Lead Zirconate ◽  
The Other ◽  
Crystalline Quality ◽  
Pzt Films ◽  
Atomically Flat

AbstractThin films of Lead-Zirconate-Titanate (PZT) have been grown by pulsed-laserdeposition (PLD) onto polished MgO substrates both with and without pre-annealing.The surface morphology of polished MgO substrates, which are widely used for deposition, is examined by AFM. Commercially available, mechanically-polished substrates are shown to be microscopically very rough and seem unlikely to present a surface suitable for the growth of the highest quality thin films. Annealed MgO substrates, on the other hand, comprise atomically flat terraces. The use of annealed substrates is found to enhance considerably the crystalline quality of PZT films deposited thereon.

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