After a pattern is transferred on silicon film crystallized by annealing, the silicon film is annealed by radiation of intense rays for a short time. Especially, in the crystallizing process by annealing, an element which promotes crystallization such as nickel is doped therein. The area not crystallized by annealing is also crystallized by radiation of intense rays and a condensed silicon film is formed. After a metal element which promotes crystallization is doped, annealing by light for a short time is performed by radiating intense rays onto the silicon film crystallized by annealing in an atmosphere containing halide. After the surface of the silicon film is oxidized by heating or by radiating intense rays in a halogenated atmosphere and an oxide film is formed on the silicon film, the oxide film is then etched. As a result, nickel in the silicon film is removed.

Process for fabricating thin film transistor

At present, a forming process of a base film through an amorphous silicon film is conducted in respective film forming chambers in order to obtain satisfactory films. When continuous formation of the base film through the amorphous silicon film is performed in a single film forming chamber with the above film formation condition, crystallization is not sufficiently attained in a crystallization process. By forming the amorphous silicon film using silane gas diluted with hydrogen, crystallization is sufficiently attained in the crystallization process even with the continuous formation of the base film through the amorphous silicon film in the single film forming chamber.

Method of Manufacturing a Semiconductor Device

There are disclosed TFTs that have excellent characteristics and can be fabricated with a high yield. The TFTs are fabricated, using an active layer crystallized by making use of nickel. Gate electrodes are comprising tantalum. Phosphorus is introduced into source/drain regions. Then, a heat treatment is performed to getter nickel element in the active layer and to drive it into the source/drain regions. At the same time, the source/drain regions can be annealed out. The gate electrodes of tantalum can withstand this heat treatment.

Semiconductor device and method of fabricating same

A semiconductor device comprising at least two thin film transistors on a substrate having an insulating surface thereon, provided that the thin film transistors are isolated by oxidizing the outer periphery of the active layer of each of the thin film transistors to the bottom to provide an oxide insulating film.

Semiconductor device and process for fabricating the same

The object of the invention is to provide a method for fabricating a semiconductor device having a peeled layer bonded to a base material with curvature. Particularly, the object is to provide a method for fabricating a display with curvature, more specifically, a light emitting device having an OLED bonded to a base material with curvature. An external force is applied to a support originally having curvature and elasticity, and the support is bonded to a peeled layer formed over a substrate. Then, when the substrate is peeled, the support returns into the original shape by the restoring force, and the peeled layer as well is curved along the shape of the support. Finally, a transfer object originally having curvature is bonded to the peeled layer, and then a device with a desired curvature is completed.

Method for fabricating a semiconductor device

Explosive crystallization of Cu implanted amorphous silicon during irradiation by a 32‐ns FWHM ruby laser pulse has been studied using time‐resolved reflectivity measurements and Rutherford backscattering spectrometry. From interferences in the reflectivity, the position and the velocity of the self‐propagating melt have been deduced as a function of time. A maximum average velocity of 13±2 m/s has been obtained. The reflectivity behavior indicates the presence of crystalline nuclei in the melt.

Time‐resolved reflectivity measurements during explosive crystallization of amorphous silicon

Si amorphized by Cu implantation has been irradiated by spatially uniform pulses of 7.5 ns duration from a frequency‐doubled neodymium:yttrium aluminum garnet laser. After irradiation the samples were examined by cross‐section transmission electron microscopy. A laterally random pattern of polycrystalline Si patches was found imbedded in amorphous material. At low‐energy densities a considerable fraction of the regrown Si was polycrystalline. With increasing energy density the amount of polycrystalline Si decreased, both at the surface and in total. These results are discussed in terms of the time available for the nucleation of polycrystalline Si at a liquid‐solid interface and the temperature profile in both the liquid and the solid material.

Between explosive crystallization and amorphous regrowth: Inhomogeneous solidification upon pulsed‐laser annealing of amorphous silicon

Amorphized Si has been irradiated using a 7.5‐ns frequency‐doubled neodymium:yttrium aluminum garnet laser. For low energy density pulses, time‐resolved reflectivity measurements and Rutherford backscattering spectrometry of Cu implantation profiles show that the melted layer solidifies from the surface as well as from the liquid‐solid interface. From interferences in the reflectivity, growth from the surface is found to occur at a velocity of 1.5 m/s. At higher energy densities sufficient to obtain epitaxial regrowth of the amorphous layer, solidification from the surface does not occur.

Direct observation of resolidification from the surface upon pulsed-laser melting of amorphous silicon

The transition between amorphous regrowth and explosive crystallization of a 220nm thick amorphous Si layer on a crystalline Si substrate has been studied using time-resolved reflectivity, transmission electron microscopy, and Rutherford backscattering spectroscopy. Upon irradiation by 7.5ns FWHM pulses from a frequency-doubled Nd:YAG laser, interferences in the reflectivity indicate growth of amorphous Si from the surface. The observation of a narrow Cu peak, buried below the surface, points towards solidification from both the rear and the front. Transmission electron microscopy studies revealed the occurrence of small patches of polycrystalline Si. The relative amount of this polycrystalline Si is increased by longer laser pulses, higher substrate temperatures, and thicker amorphous Si layers. The results are discussed in terms of the temperature distribution and the time available for the nucleation of polycrystalline Si at the liquid-solid interface.

J. J. P. Bruines

Papers

Time‐resolved reflectivity measurements during explosive crystallization of amorphous silicon

Between explosive crystallization and amorphous regrowth: Inhomogeneous solidification upon pulsed‐laser annealing of amorphous silicon

Direct observation of resolidification from the surface upon pulsed-laser melting of amorphous silicon

The Transition Between Amorphous Regrowth and Explosive Crystallization