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Thin-film transistors (TFTs) were fabricated on polycrystalline silicon (poly-Si) films formed by position-controlled large-grain growth technology using an excimer laser. The field-effect mobility, on-off transition slope, and threshold voltage were 914 cm2 V-1 s-1, 93 mV/decade, and 0.58 V for the n-channel device, and 254 cm2 V-1 s-1, 122 mV/decade, and -0.43 V for the p-channel device, respectively. These values indicate that TFTs had an ultrahigh performance comparable to that of {100}-oriented crystal-silicon metal–oxide–semiconductor (MOS) transistors. Furthermore, their effective mobilities had the same effective field and temperature dependences as those of MOS transistors, indicating that electrons and holes were predominantly scattered not by random grain boundaries or defects in the Si film, but by phonons at the SiO2–Si interface, similarly to those of crystal-silicon MOS transistors. These attractive results were obtained as a result of the fact that the TFT channel region was made up of nearly {100}-oriented single grains.

The factors affecting the elongation of Si grains were investigated for the excimer-laser-induced lateral grain growth method. The length of Si grains was found to depend on the laser light intensity profile, the waveform of the laser light pulse, particularly at its tail region, and the sample structure. Grains as long as 25 µm were successfully grown at room temperature using a combination of a V-shaped light intensity profile, a light pulse waveform with a long tail, and a stacked sample structure with a cap layer. Grains of 11 µm in length were also grown in a capless sample.

We have developed a method of preselecting a lucky nucleus among many simultaneously born nuclei for the growth of position-controlled large single Si grains by excimer-laser-induced lateral crystallization. Using this method, arrays of large Si grain of almost 5 ×5 µm2 size were successfully grown with a single shot. The result of electron backscattering diffraction pattern (EBSP) analysis indicated that most of the large Si grains had no random boundaries inside, which means that each grain grew from only a preselected lucky nucleus. It was confirmed that the margins to the vertical mispositioning of the sample surface from the focal point and also to the fluctuation of average irradiation light intensity were sufficiently large. Therefore, our method seems to be very attractive for industrial applications.

A wide process window has been achieved for "the phase-modulated excimer-laser annealing" method of Si thin films. Ordinary and extraordinary light rays resulting from the birefringence effects of a crystal quartz plate, which is newly introduced within the optical path of the annealing system, generate a pair of projected images of a phase modulator. By adjusting their separation to be half the modulator pattern pitch, undesirable deformations, which appear in pair images owing to defocus, cancel each other out, resulting in a stable superposed image (light intensity profile) on the sample surface. It is shown by optical simulation and experiment that this "double-image method" widens the depth of focus from less than 2 µm to as wide as about ±6 µm.

The dependences of field-effect mobility, threshold voltage, and subthreshold slope on temperature for low-temperature polycrystalline silicon (LTPS) thin film transistors (TFTs) with large grains were investigated. It was shown that the temperature dependences of field-effect mobility and threshold voltage are affected by the temperature dependence of negatively charged grain-boundary-related interface traps near the surface of polycrystalline silicon, which is explained by considering that the degree of band bending at the surface when gate voltage is equal to threshold voltage decreases with increasing temperature. It was also shown that the behavior of a subthreshold slope can be explained using a term of the grain-boundary-related interface traps near the surface. Moreover, the effects of grain boundaries on hot-carrier generation and hot-carrier-induced degradation were investigated separately, and both processes were experimentally found to be affected by the grain boundaries.

The fluctuation of the light intensity distribution on a sample surface has an adverse effect in lateral Si crystallization methods, such as phase-modulated excimer-laser annealing (PMELA). Consequently, the origins of various fluctuations must be examined precisely and suppressed satisfactorily and independently. In particular, the phase modulator, which mainly determines the microscopic light intensity distribution, must be checked carefully. We have developed a stand-alone visible-light check system for phase modulators, by taking different wavelength effects into account, and have confirmed the usefulness of the system.

Polycrystalline silicon (poly-Si) complementary metal–oxide–semiconductor (CMOS) circuits have been fabricated by using an advanced excimer-laser annealing method and a plasma-oxidation method. The 1-µm-long thin-film transistors (TFTs) were fabricated on arrays of laterally grown long and narrow grains, so that the majority of carriers were free from scattering at grain boundaries during propagation through the channel. The propagation delay time measured by a 21-stage ring oscillator was 175 ps and a power-delay product of 9×10-13 J/gate was obtained at a supply voltage of 3.3 V. The obtained propagation delay time was almost the same as those of bulk Si devices having the same gate length. Furthermore, we expect that 1-µm-long CMOS TFT circuits on glass will have a performance superior to that of 1-µm-long bulk Si devices when the short channel effect and threshold voltage fluctuation are controlled well.

We have investigated the effects of impurities in starting silicon films on excimer-laser-induced lateral growth characteristics. The films should have a low concentration of impurities to achieve long lateral growth, since impurities, such as carbon, nitrogen, oxygen, and fluorine, in the films were found to affect the lateral growth characteristics severely. A stacked structure with a capping layer is also considered essential for maintaining pure molten Si during lateral growth.

Excellent characteristics of polycrystalline silicon (poly-Si) thin-film transistors (TFTs) with long and narrow grains aligned one-dimension have been experimentally clarified for the first time. The field effect mobility and on-off transition slope of n-channel and p-channel devices were as high as 685 cm2 V-1 s-1 and 190 mV/decade and 145 cm2 V-1 s-1 and 104 mV/decade, respectively. Fluctuations of characteristics were considerably reduced by widening the channel, and uniform characteristics were observed when there were approximately twenty long grains within the channel. These results were obtained when the TFT channel was formed within a region free from grain boundaries formed by head-on collision of laterally growing grains and seeds used to initiate lateral grain growth. Material properties are discussed from the viewpoint of device characteristics.

Characteristics have been investigated for both KrF excimer-laser light and KrF excimer-laser crystallization of Si thin films. The results were applied to design an optical system for growing densely packed and large grains. A high-resolution beam profiler confirmed that the laser light intensity distribution on the sample surface had a nearly ideal triangular form with a maximum-to-minimum intensity ratio of approximately 2, as designed. This distribution could grow 5-µm-long grains with a packing efficiency close to 100% by a single laser light pulse.

Microtexture was analyzed for Si films crystallized by a phase-modulated excimer laser annealing method, using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Electron Back-Scattering Pattern (EBSP). Threshold fluences were identified for crystallization, lateral growth and film braking, by comparing the surface morphology and the microscopic excimer laser light intensity profile. It was found that {001} and {110} orientations are preferable for lateral growth direction but the surface orientation is random. A possible origin of preferable orientations for laterally grown film was discussed.

60-µm-long grains were grown laterally in a 50-nm-thick Si layer on thermally grown oxide by a single shot irradiation of an excimer-laser-light pulse. The origin of such a marked (about 10 times) enlargement of grains can be found in a newly introduced photosensitive capping layer on the Si layer, which has been heated uniformly to extremely high temperatures by absorbing a fraction of excimer-laser-light and gradually transfers the stored heat to the Si layer after the laser irradiation, resulting in the extension of the liquid-phase duration of the Si layer. Ultrathinning the Si layer can effectively reduce the lateral heat loss along the highly heat-conductive, liquid or crystallized Si layer, and, in turn, extend the liquid-phase duration further. SiON and SiOC films are good candidates for the photosensitive capping layer, although SiOC is preferable since it can be etched by a buffered HF solution and has an appropriate light absorption coefficient for a broad band of laser-light-wavelengths.

One-monolayer deposition characteristics have been investigated for Ge on the Si(1 0 0) surface and Si on the Ge(1 0 0) surface by using a co-axial impact collision ion scattering spectroscopy. A subtracted spectrum method has been proposed for the detailed analysis of the interface structure. Incident angle dependence of the signal intensity shows that both Ge/Si and Si/Ge hetero-interfaces are atomically abrupt without intermixing and surface segregation.

Optimization has been done theoretically for the phase-modulated excimer-laser annealing method to grow highly packed large grains in the Si film, where the divergence of the laser light beam plays an important role. Generalized optimum annealing conditions were given graphically as a function of the maximum-to-minimum light intensity ratio. Theoretical results were verified also experimentally by growing grains as large as 7 μm with 10 μm-pitch using a single shot of excimer-laser light pulse. It is pointed out that there is a room for improving the packing density to almost 100% by simply shortening the pitch of the phase shifters.

Advanced excimer-laser-annealing (ELA) technologies of Si thin films on glass have been reviewed. ELA-induced lateral grain growth seems attractive from an application view point since grains more than several microns in length can be grown by single shot of an excimer-laser light pulse. There are two technological ways for enhancing lateral growth kinetics. The one is introduction of non-uniform light intensity on the sample surface. Different values of thermal energy density stored in the molten Si film results in its solidification time delay along the sample surface, which triggers the long lateral grain growth. The other is an application of a non-uniform sample structure, which causes a non-uniform heat removal rate, resulting in the solidification time delay. An underlayer plays also very important role in ELA. By using organic SOG as the underlayer, grains more than 20 microns in length could be grown, and by using porous silica the grain size became more than 0.1 mm. These lateral growth technologies seem applicable not only to thin-film transistors but also to solar cells.

Silica films with various types of alkyl groups were grown from the liquid phase, at room temperature, using alkyl tri-alkoxy silane compounds. From Fourier transform infrared (FTIR) absorption measurements, a majority of Si-alkyl bonds in the source molecules were found to remain in the grown film, while Si-alkoxy bonds were completely removed. Electrical and thermal properties have been measured comparatively for various films having dense alkyl groups. The films with the methyl group are promising for silicon production in ultra large-scale integrated circuits (Si-ULSIs) and the film having the vinyl group for non-heat-tolerant compound-semiconductor large-scale integrated circuits (LSIs).

Chemical vapor deposition parameters have been investigated for low (∼200°C) temperature deposited and hydrogen-free SiO 2 films from a mixture of tetra-iso-cyanate-silane and various kinds of tertiary-alkyl-amine. Di-methyl mono-ethyl amine was found the most suitable partner gas for H free low temprature CVD source gas mixture. Addition of small amount of H 2 O (0.5% of tertiary-alkyl-amine) was effective for decreasing the deposition temperature up to 50°C without serious drawbacks on the film properties such as hydration and electric properties. The deposition rate increased to higher temperatures by using those best partner gases, di-methyl mono-ethyl amine, with tetra-iso-cyanate-silane. The resistivity defined at 1 MV cm −2 was >10 16 Ω cm, and breakdown field strength at 1 μA cm −2 was >6 MV cm −2 . The fixed-charge density and interface sate density near midgap were ∼4 × 10 12 cm −2 and ∼10 12 eV −1 cm −2 respectively.

An advanced excimer-laser annealing method, named phase-modulated excimer-laser annealing method, has been reviewed for large-grain growth in Si thin-films. The laser-light intensity is modulated two-dimensionally on the Si film surface that triggers a lateral motion of the melt–solid interface, resulting in the lateral grain growth. The intensity distribution can be designed well by a phase-shift concept. Large grains were grown at pre-designed positions at 500°C, and are expected to possibly be aligned with less than 30 μm in pitch. The method seems attractive for high-performance and quasi single-crystal thin-film devices, which include thin-film transistors, silicon-on-insulator-based ULSIs, solar-cells and porous Si photonic devices.

Reaction process has been studied for an atomic hydrogen-induced abstraction of methyl groups on the Ge surface. The reaction rate estimated from experiments had a very large activation energy and depended on a surface coverage of methyl groups; they are not expected for a `pure' Eley–Rideal mechanism. The process can be explained by the `modified' Eley–Rideal mechanism or the `precursor' mechanism based on two-dimensionally bound hydrogen atoms on the surface.

We achieved the atomic-layer-deposition of SiO2 with an extremely low H content for the first time by using Si(NCO)4 and N(C2H5)3. The deposition rate was independent of the exposure times of both sources. The saturated deposition rate was about 1.2 A/cycle at 150°C. AFM observation revealed that the increase of roughness after 50 deposition cycles was only about 0.4 A in root mean square. The FT-IR spectra showed that the deposited film was SiO2 without Si–H, Si–OH or NCO bond.

Atomic layer epitaxy of silicon has been studied by alternating exposures of atomic hydrogen and SiH2Cl2. An ideal growth rate of 1 monolayer per cycle has been achieved with a wide temperature window from 550 °C to 610 °C under long SiH2Cl2 residence time and high pressure conditions. These requirements seem to come from the generation of dense SiHCl, the desirable precursor, by gas-phase reaction of SiH2Cl2.

We have proposed heterojunction thin-film transistors having a stacked structure of poly-crystal silicon-carbon (SiC/sub x/) and Si thin films, both of which are prepared by an excimer-laser crystallization method. A Si/SiC/sub x/ interface after intense excimer-laser irradiation for crystallization, was as abrupt as that of the as-deposited and amorphous structure. The device had a relatively high mobility of about 4 cm/sup 2//Vs and a sufficiently low leakage current of an order of 10/sup -14/ A//spl mu/m even under intense light illumination conditions.

Atomic-layer-epitaxy (ALE) of germanium has been analyzed by a kinetic model and a thermodynamic model. Chlorogermanes are found to be unsuitable since they cannot satisfy the self-limiting adsorption condition due to quick thermal desorption of HCl from the surface. On the other hand, the ideal growth rate of one monolayer per cycle is expected for dimethylgermane. This is because there exists no recombinative desorption reaction between surface methyl groups and H that will break the self-limiting adsorption condition. It has also been confirmed, from thermodynamic considerations, that the elemental chemical reactions used in this ALE, i.e., self-limiting adsorption and reduction of surface methyl groups by atomic hydrogen, are spontaneous.

Atomic layer etching of Ge has been investigated experimentally based on the surface chemistry that Cl can adsorb on the clean Ge surface at room temperature and desorb thermally as GeCl 2 at high temperatures. The ideal etching rate of one monolayer per cycle has been achieved. The critical Cl 2 dosage for the saturated etching rate was about 7.2×10 6 L. Increase of the surface roughness after etching of 100 cycles was about 3.5 monolayers.

A kinetic model has been presented for atomic layer epitaxy of Si using cyclic exposures of SiH 2 Cl 2 and atomic hydrogen. This model is based on the surface reaction of adsorbates formed by gas-phase reaction of SiH 2 Cl 2 . The ideal growth rate of one monolayer per cycle is achieved only when the dominant precursor is SiHCl. Limiting factors of the ALE window are also discussed.

Self-limiting monolayer adsorption of Ge has been demonstrated on Si(100) at 520°C using dimethylgermane as a self-limiting molecular precursor. This opens a way for hetero-ALE of Ge on the Si surface.

A new poly-crystal silicon thin-film transistor (poly-Si TFT) with a transparent bottom-gate electrode has been fabricated by XeF excimer-laser light irradiation from the glass substrate side. Compared with poly-Si TFTs made by XeF or ArF excimer-laser light irradiation to the top Si surface, the new TFT shows a higher electron mobility of about 100 cm/sup 2//Vs, independent of the Si film thickness. Therefore, poly-Si driver TFTs and amorphous-silicon (a-Si) TFTs for the matrix can be formed with the same channel-etch type bottom-gate structure simultaneously on the same glass substrate by using the same starting materials. This is expected to open the way for making driver monolithic and active matrix liquid crystal displays.

Atomic layer epitaxy of germanium has been demonstrated successfully by alternating exposures of atomic hydrogen, which acts as a reactant for extracting hydrocarbon from the surface, and of dimethylgermane as a self-limiting molecular precursor. The ideal growth rate of one monolayer per cycle has been achieved with a wide ALE temperature window between 420°C and 528°C.

Based on the first result of the layer-by-layer deposition of silicon dioxide films by a cyclic exposure of water and tetra isocyanate silane, Si(NCO) 4 , new isocyanate compounds preferable to Si(NCO) 4 have been proposed for ideal layer-by-layer deposition characteristics. Preliminary results are also presented for one of the substances.

Two methods are proposed and demonstrated successfully for low temperature atomic layer epitaxy (ALE) of Si, where H atoms play essential roles. The first method is the use of H as a self-limiting factor. Trisilane (Si3H8) was used as source gas and the substrate temperature was modulated in order to alternate steps in an ALE cycle. When the temperature was less than 380°C in the adsorption step and more than 520°C in the desorption step, respectively, the grown layer thickness per cycle was 0.8 ML/cycle. The second method is the use of atomic H as an active reducer of a self-limiting factor. A clean surface was exposed to dichlorosilane (SiH2Cl2) as source gas to grow an Si monolayer covered with CI. Next, atomic H was injected to reduce CI from the surface. An ideal monolayer growth was obtained with the substrate temperature over 540°C.

Novel atomic layer epitaxy (ALE) methods have been proposed for Ge, where the elemental kinetics of the chemical vapor deposition method are divided into two sequential phases, i.e., a monolayer adsorption phase and a subsequent desorption phase for the surface-terminating species. Ge-ALE has been achieved, for the first time, with an ideal growth rate of one monolayer per cycle, under constant substrate temperature conditions. The detailed ALE method and growth characteristics have been presented. Furthermore, atomic hydrogen exposure is shown to be effective for widening the Ge-ALE window.

Two ALE methods of Si are successfully demonstrated, where H atoms play an essential role. In the first method, H atoms are used as self-limiting species over the grown layer. Si3H8 was used as source gas and the substrate temperature was modulated in order to switch two steps, i.e. an adsorption step and a desorption step, in an ALE cycle. When the temperature was lower than 380°C in the adsorption step and higher than 520°C in the desorption step, the grown layer thickness per cycle was saturated at 0.8 ML/cycle, closer to the ideal value than in the SiH4 or Si2H6 cases. In the second method, atomic H is used as an active reducer of the self-limiting species. SiH2Cl2 as source gas and atomic H were irradiated to the surface, alternately. An ideal monolayer growth per cycle was obtained with the substrate temperature over 540°C, much lower than in the case of the molecular H2 reducer.

SiO2 films were deposited layer by layer from a new silicon source gas, i.e. tetra-iso-cyanate-silane (Si(NCO)4). An average growth rate of about 0.17 nm per cycle was achieved by a cyclic process of alternating reaction of the substrate surface with Si(NCO)4 and H2O respectively. The detailed deposition characteristics together with chemical and physical properties of the deposited film were evaluated with ellipsometry, Fourier transform IR spectroscopy, X-ray photoelectron spectroscopy and Auger electron spectroscopy.

We have found that an undesirable SiNH component is reduced drastically from the low-temperature-deposited SiN surface by intense ArF excimer-laser irradiation on the low-temperature-deposited SiN film. This pre-annealing of the SiN film is very effective in forming an abrupt Si/SiN interface, and thus plays a very important role in high-performance excimer-laser-crystallized poly-Si/SiN thin-film transistors aiming at high-quality liquid-crystal displays. Annealing characteristics are also presented for the various SiN film thickness and for both the ArF and KrF excimer-laser lights.

A microstructure has been introduced into the channel of amorphous-silicon thin-film transistors with poly-silicon sources and drains. A slant-photolithography method was introduced for fabricating this device without additional photomasks. The off-characteristics have been improved without sacrificing originally good on-characteristics. Temperature dependence is also discussed for the transistor characteristics. >

Atomic H is proposed for the reducer gas in the atomic layer epitaxy (ALE) of Si. Its high reactivity makes it possible to remove surface-terminating adsorbates, which cause the self-limitation of unwanted successive deposition of Si compounds, at low temperature. The ALE growth was attempted by the alternating exposure of the Si(111) substrate to SiH 2 Cl 2 and H. Ideal monolayer growth was obtained and the growth rate was independent of the gas volumes and the substrate temperature. The lower ALE limit of the substrate temperature was 540 °C, about 250 °C lower than the case of H 2 as the reducer gas.

High-mobility poly-Si thin-film transistors (TFTs) were fabricated by a novel excimer laser crystallization method based on dual-beam irradiation. The new method can reduce the solidification velocity of the top Si layer by heating the bottom Si layer of the Si/SiO/sub 2//Si/glass substrate structure by means of laser irradiation not only from the front side but also from the back side. The grain size of poly-Si film was enlarged up to 2 mu m. The field-effect mobilities of the TFT exceeded 380 cm/sup 2//V-s for electrons and 100 cm/sup 2//V-s for holes. >

The characteristics of amorphous silicon thin-film transistors fabricated by chemical vapor deposition method is discussed in detail in conjunction with posthydrogenation. As the hydrogenation around an active interface starts, the transistor performance is abruptly improved and then does not change with further hydrogenation. A critical condition for hydrogenation for such an abrupt improvement may be accounted for based on a simple formula using a transit time of hydrogen atoms. A desirable thickness of amorphous silicon films for high performance TFT is thicker than 100 nm. In addition, it is recommended that hydrogenation is to be made at a temperature as low as possible as long as it can be possible.

A new Si thin-film transistor (TFT) has been proposed where only one grain-boundary exists at the center of channel, and the source and drain are within single grains with good crystallinity. The device fabricated by an excimer-laser crystallization method at the maximum temperature of 500/spl deg/C, had the on-off current ratio /spl cong/10/sup 6/, the field-effect mobility /spl cong/330 cm/sup 2//Vs and the subthreshold swing /spl cong/1.1 V/dec, respectively, For the device processed at 800/spl deg/C, they are >10/sup 6/, >450 cm/sup 2//Vs and /spl cong/0.51 V/dec, respectively.

Hot ion-implantation has been applied to threshold voltage control of amorphous-silicon thin-film transistors. A threshold voltage shift as large as 13 V has been achieved without deterioration of the field-effect mobility. The technique was also used to form distributed-threshold voltage transistors which have a microstructure inside the channel. It was verified that the off-characteristics were greatly improved. >

Low-temperature CVD method has been investigated for silicon-nitride films by using higher silanes and hydrazine aiming at thin-film transistor application. The deposition temperature has been reduced to as low as 350°C, i.e., by about 400°C lower than the typical temperature. Atomic N/Si ratio was more than 4/3, i.e., the film was stoichiometric SiN, and hydrogen content was as high as 20 atomic%. Breakdown field strength, specific resistivity and MIS interface state density were about 6MV/cm, 6x1015 Ωcm and 1x1011cm-2eV-1, respectively.

Amorphous silicon (a-Si) Thin Film Transistors (TFT) will continue to play an important role in large-area liquid crystal displays (LCD), however, there is also a strong demand for ultra-high performance TFTs aimed at intelligent small (or medium) size displays. For this reason, “Crystal Si on glass” has become an increasingly attractive solution. This paper reviews recent work performed at ALTEDEC (Advanced LCD Technologies Development Center Co., Ltd, with regard to growing an array of large Si grains at low temperature. The results obtained so far indicate that satisfactory progress has been made towards the achievement of this goal.

Experimental and theoretical results are reviewed for an excimer-laser-based Si large-grain growth method aiming at a 'system-on-panel' technology. Temperature in the Si thin layer should have a gentle slope along the one direction for growing large grains and should have a steep dip along the other direction for controlling their positions. In order to produce such a temperature distribution using an excimer- laser light pulse, phase-shifter patterns that generate the 2D distribution of the light intensity on the sample surface by Fresnel effects should be independently optimized for both directions. The sample should be of a stacked structure of the heat storage layer, the Si layer and the underlayer with low heat diffusing power. The Si layer thickness is a critical parameter for long grain growth, and should be very thin under the condition of the thick heat storage layer. The growth large grains seem to have excellent crystallinity although experimental data is not sufficient.

This paper reviews an excimer-laser annealing (ELA) method of Si thin-films on glass studied in the Tokyo Institute of Technology, aiming at position-controlled ultra-large grain growth with high packing density by a single shot irradiation of a laser-light pulse. Key concepts are (I) 2-D modulation of the laser light intensity on the sample surface, (II) reduction of the heat removal rate from the molten Si thin layer of high temperature, and (III) enlargement of the effective specific-heat while keeping the effective thermal-conductivity low for annealed layers. There were two possible solutions for the condition (I). The first solution is of an application of a cross-coupled phase-shifter formed on a transparent quartz plate. The second solution is of a half-tone phase-modulation method (PAMELA method) using semi-transparent thin films on quartz substrate with phase-shifter. The condition (II) is satisfied by changing the SiO2 underlayer to the porous or organic silica underlayer for reducing vertical heat flow flux to the cool underlayer, and by thinning the Si layer for reducing heat flow flux along the highly conductive Si layer. The condition (III) is satisfied, by the SiON capping layer for a KrF excimer laser, and by the SiOC capping layer for a XeCl excimer laser, since they have a reasonable light absorption coefficient, low thermal conductivity, large specific-heat and sufficient heat tolerance.

Stoichiometric boron‐nitride films have been successfully deposited at temperatures as low as 400 °C by chemical vapor deposition using diborane (B2H6) and hydrogen azide (HN3). The film deposited on the silicon substrate at 475 °C was amorphous and contained hydrogen atoms with a density of 1.3×1022 cm−3. The breakdown field strength and the low‐field resistivity were 2.8 MV/cm and 1015 Ω cm, respectively. The optical and low‐frequency dielectric constants were 3.6 and 4.0, respectively. Metal‐insulator‐metal device equipped with this film showed steep current‐voltage characteristics.

An excimer-laser-induced large-grain growth method has been proposed which utilizes non-uniform heat diffusion along the Si thin-film and also along the underlayer. A single-shot of KrF excimer-laser light pulse with uniform intensity could crystallize a circularly pre-patterned Si thin-film of 20νm in diameter, much larger than TFT feature size in present AM-LCD panels.