WO2004040628A1 - レーザを用いた結晶膜の製造方法及び結晶膜 - Google Patents
レーザを用いた結晶膜の製造方法及び結晶膜 Download PDFInfo
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- WO2004040628A1 WO2004040628A1 PCT/JP2003/013141 JP0313141W WO2004040628A1 WO 2004040628 A1 WO2004040628 A1 WO 2004040628A1 JP 0313141 W JP0313141 W JP 0313141W WO 2004040628 A1 WO2004040628 A1 WO 2004040628A1
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- 238000000034 method Methods 0.000 title claims description 43
- 230000008569 process Effects 0.000 title claims description 7
- 239000013078 crystal Substances 0.000 claims abstract description 311
- 239000010409 thin film Substances 0.000 claims abstract description 64
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02656—Special treatments
- H01L21/02664—Aftertreatments
- H01L21/02667—Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
- H01L21/02675—Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth using laser beams
- H01L21/02686—Pulsed laser beam
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/20—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02367—Substrates
- H01L21/0237—Materials
- H01L21/02422—Non-crystalline insulating materials, e.g. glass, polymers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02436—Intermediate layers between substrates and deposited layers
- H01L21/02439—Materials
- H01L21/02441—Group 14 semiconducting materials
- H01L21/0245—Silicon, silicon germanium, germanium
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- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02436—Intermediate layers between substrates and deposited layers
- H01L21/02439—Materials
- H01L21/02488—Insulating materials
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02656—Special treatments
- H01L21/02664—Aftertreatments
- H01L21/02667—Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
- H01L21/02675—Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth using laser beams
- H01L21/02678—Beam shaping, e.g. using a mask
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02656—Special treatments
- H01L21/02664—Aftertreatments
- H01L21/02667—Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
- H01L21/02691—Scanning of a beam
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/26—Bombardment with radiation
- H01L21/263—Bombardment with radiation with high-energy radiation
- H01L21/268—Bombardment with radiation with high-energy radiation using electromagnetic radiation, e.g. laser radiation
Definitions
- the present invention relates to a method for manufacturing a crystal film and a crystal film, and more particularly to a method for manufacturing a crystal film in which a laser beam is incident on an amorphous film for crystallization.
- the crystal film can be used for a low-temperature polycrystalline TFT liquid crystal display, a solar cell panel, a single-panel liquid crystal display, an organic EL display, and the like.
- Excimer laser is applied to an amorphous silicon thin film to repeat melting and solidification, and to grow crystals in the lateral direction (in-plane direction of the thin film). It has been known. Hereinafter, the conventional SLS technology will be described.
- magnification of this imaging optical system is, for example, 1 /
- the width of the region irradiated with the laser beam on the surface of the amorphous silicon film is about 1 to 10 ⁇ m and the length is about 33.
- the beam intensity distribution in the width direction of the irradiated area is close to a rectangle.
- the amorphous silicon melts. Since the cooling rate near the edge of the melted region is faster than the internal cooling rate, solidification starts from the portion near the edge. The solidified part becomes a nucleus, and crystals grow from this nucleus toward the inside of the molten part. Since crystal growth starts from the longer two edges of the irradiated region, grain boundaries of crystal grains grown from both sides are formed almost at the center in the width direction of the irradiated region.
- the irradiation area of the pulsed laser beam is shifted in the width direction by about 50% of the width.
- One side of the grain boundary formed almost at the center of the irradiated area at the time of the first pulsed laser irradiation is re-melted.
- the crystal grains in the region not remelted become seed crystals, and the crystal grows in the region remelted.
- the crystal By repeating the laser irradiation while moving the irradiation area of the pulse laser beam, the crystal can be grown in the moving direction of the irradiation area.
- Patent Literatures 1 to 3 below describe a technology that uses a second harmonic of an Nd: YAG laser to shape the beam cross section into a linear shape, irradiates the amorphous silicon layer, and grows crystals laterally. Is disclosed. Patent Documents 4 and 5 disclose a technique of irradiating an amorphous silicon layer through a patterned mask using an excimer laser to grow crystals in a lateral direction.
- Patent Document 1 Japanese Patent Application Laid-Open No. 2000-260731
- Patent Document 2 Japanese Patent Application Laid-Open No. 2000-28086
- Patent Document 3 Japanese Patent Application Laid-Open No. 2000-2808611
- Patent Document 4 Japanese Patent Application Publication No. 2000-500-241
- Patent Document 5 Japanese Patent Application Laid-Open No. 2001-27074
- a step of preparing a workpiece on which a thin film made of an amorphous material is formed on a surface and (b) a pulse laser having a beam cross section long in one direction on the surface of the thin film.
- One beam is incident on the thin film, the thin film is melted and then solidified, and from the edge and the central axis of the area between the edge extending in the long axis direction of the beam incident area and the center line.
- a first band-shaped region defined by a virtual line separated by a distance of and a center line of the beam incident region crystal grains connected in the longitudinal direction are generated, and one of the center lines is formed.
- FIG. 1 is a schematic plan view of a laser annealing device used in the embodiment.
- FIG. 2A is a cross-sectional view of an object to be processed and a graph showing a pulse energy density distribution of a pulse laser beam used in the first embodiment on the surface of the object to be processed.
- FIG. 2B is a schematic plan view of a polycrystallized processing object.
- FIG. 3 is a sketch of an SEM photograph of a polycrystalline film produced by the method according to the first embodiment.
- FIG. 4A is a graph showing the relationship between the temperature of molten silicon and the crystal growth rate
- FIG. 4B is a graph showing the relationship between the temperature and the nucleation rate.
- Figure 5A is a graph showing the relationship between beam cross-section width and crystal grain size.
- 5B is a graph showing the relationship between the gradient of the pulse energy density distribution and the size of the crystal grains.
- FIG. 6 is a graph showing the relationship between the pulse width and the crystal grain size.
- FIG. 7 is a graph showing an example of a laser beam waveform when a two-shot pulse laser beam is incident on one location.
- FIG. 8 is a diagram schematically illustrating a cross section of a thin film in the course of manufacture in the method for manufacturing a polycrystalline film according to the second embodiment.
- FIG. 9 is a diagram in which an SEM photograph of a polycrystalline film manufactured by the method according to the second embodiment is sketched.
- FIG. 10 is a graph showing the relationship between the length of crystal growth per irradiation and the overlap ratio necessary for polycrystallizing the entire surface.
- FIG. 11 is a graph showing the wavelength dependence of the absorption coefficient of single crystal silicon and amorphous silicon.
- FIG. 12A is a diagram showing the relationship between the pulse energy density distribution of the pulse laser beam used in the method for manufacturing a polycrystalline film according to the third embodiment and the polycrystalline region, and FIG. It is a schematic plan view of the manufactured polycrystalline film.
- FIG. 13A is a diagram showing the relationship between the pulse energy density distribution of the pulse laser beam used in the method for manufacturing a polycrystalline film according to the fourth embodiment and the polycrystalline region
- FIG. FIG. 4 is a schematic plan view of a polycrystalline film obtained.
- FIG. 14 is a cross-sectional view of a substrate to be processed and a light shielding plate used in the method of manufacturing a polycrystalline film according to the fifth embodiment, and a graph showing a distribution of pulse energy density.
- FIGS. 158 to 15C are schematic diagrams showing a state of polycrystallization by the method of manufacturing a polycrystalline film according to the fifth embodiment.
- FIG. 16 is a cross-sectional view of a substrate to be processed and a light shielding plate used in the method for manufacturing a polycrystalline film according to the sixth embodiment, and a graph showing the distribution of pulse energy density.
- FIGS. 178 to 17C are schematic diagrams showing the state of polycrystallization by the method of manufacturing a polycrystalline film according to the sixth embodiment.
- FIG. 1 shows a schematic view of a laser annealing apparatus used in an embodiment of the present invention.
- the laser annealing device includes a processing chamber 40, a transfer chamber 82, a loading / unloading chamber 83, 84, a laser light source 71, a homogenizer 72, a CCD camera 88, and a video monitor 89.
- a linear motion mechanism 60 including a bellows 67, coupling members 63 and 65, a linear guide mechanism 64 and a linear motor 66 is attached to the processing chamber 40.
- the linear motion mechanism 60 can translate the stage 44 disposed in the processing chamber 60.
- the processing chamber 40 and the transfer chamber 82 are connected via a gate valve 85, and the transfer chamber 82 and the carry-in / out chamber 83, and the transfer chamber 82 and the carry-in / out chamber 84 are respectively connected to the gate valve 86. And 87 are linked. Vacuum pumps 91, 92 and 93 are attached to the processing chamber 40 and the loading / unloading chambers 83 and 84, respectively, so that the inside of each chamber can be evacuated.
- a transfer port pot 94 is housed in the transfer chamber 82. The transfer robot 94 transfers the processing substrate between the processing chamber 40 and the loading / unloading chambers 83 and 84.
- a quartz window 38 for transmitting a laser beam is provided on the upper surface of the processing chamber 40.
- a visible optical glass such as BK7 may be used instead of quartz.
- Laser The pulsed laser beam output from the light source 71 passes through Athens 76 and enters the homogenizer 72.
- the homogenizer 72 makes the cross-sectional shape of the laser beam slender and makes the intensity in the major axis direction uniform.
- the laser beam that has passed through the homogenizer 72 passes through an elongated quartz window 38 corresponding to the cross-sectional shape of the beam, and enters the processing substrate held on the stage 44 in the processing chamber 40.
- the relative position between the homogenizer 72 and the processing substrate is adjusted so that the surface of the substrate coincides with the homogenized surface.
- the direction in which the stage 44 is translated by the linear motion mechanism 60 is a direction orthogonal to the long direction of the quartz window 38. This makes it possible to irradiate a large area on the surface of the substrate with the laser beam and to polycrystallize the amorphous semiconductor film formed on the surface of the substrate.
- the substrate surface is photographed by a CCD camera 88, and the substrate surface being processed can be observed on a video monitor 89.
- FIGS. 2 and 3 a method of manufacturing a polycrystalline film according to the first embodiment will be described.
- FIG. 2A shows a cross-sectional view of the object 1 and an example of the distribution of the pulse energy density in the short axis direction of the laser beam on the surface of the object 1.
- the object to be processed 1 is a glass substrate 2 having a thickness of 0.7 mm, an oxide silicon film 3 having a thickness of 100 nm covering the surface thereof, and a silicon substrate 3 having a thickness of 50 nm formed on the surface thereof. It has a three-layer structure composed of an amorphous silicon film 4.
- the silicon oxide film 3 is formed by, for example, chemical vapor deposition (CVD) or sputtering.
- the amorphous silicon film 4 is formed by, for example, reduced-pressure C VD (LP-C VD) or plasma-excited C VD (PE-C VD).
- the distribution 5 of the pulse energy density in the minor axis direction of the beam cross section can be approximated by a Gaussian distribution.
- the amorphous silicon film 4 in the region 6 where the laser beam with the pulse energy density equal to or higher than the threshold value Eth for completely melting the amorphous silicon is completely melted.
- "completely” means that the silicon film melts over the entire thickness.
- the silicon film is partially melted.
- “partially” means that a part of the silicon film is melted, but a part which is not melted in the amorphous state remains.
- the amorphous silicon film 4 in the region 9 outside the position where the pulse energy density becomes Ec does not melt. When the molten silicon solidifies, silicon crystal grains are formed.
- the inventor of the present application has found that relatively large crystal grains are formed in the band-shaped region 7 near the position where the pulse energy density becomes the threshold value Eth, and small fine crystal grains are formed in the region 8 inside the band-shaped region 7.
- the region 12 it was found that crystal grains having a size intermediate between the size of the crystal grains in the region 8 and the size of the crystal grains in the band-shaped region 7 were randomly distributed.
- the “size of crystal grains” means the average size of crystal grains distributed in the region.
- FIG. 2B shows a schematic plan view of a region irradiated with the pulsed laser beam.
- the vertical direction in Fig. 2B corresponds to the long axis direction of the beam incident area.
- Long axis of beam incident area Between the edge 10 extending in the _ direction and the center line 11, a band-like region 7 extending in the long axis direction is arranged.
- the band-shaped region 7 is arranged at a certain distance from the edge 10 of the beam incident region.
- a large number of crystal grains 13 connected in the long axis direction are formed in the belt-shaped region 7.
- the intensity distribution of the pulse laser beam in the short axis direction is approximated by a Gaussian distribution.
- the half value width of the intensity distribution in the minor axis direction is called the beam width.
- both sides of the area corresponding to the beam width on the surface of the object to be processed are irradiated with the beam component at the foot of the Gaussian distribution.
- the edge 10 of the beam incident area can be defined as, for example, a portion where the maximum value of the pulse energy density is 10%.
- Figure 3 shows a sketch of a scanning electron micrograph (SEM) of a polycrystalline silicon film.
- the incident pulse laser beam is the second harmonic (wavelength 527 nm or 524 nm) of the Nd: YLF laser, and the pulse width is 100 ns.
- the length of the beam cross section on the workpiece surface in the major axis direction is 5 mm, and the beam width is 0.2 mm.
- the effective pulse energy density is 1 J / cm 2 .
- the pulse energy density is calculated by dividing the pulse energy by the area of the beam cross-section on the surface of the object to be processed, and relatively large crystal grains are formed in the belt-shaped region 7 and are connected in the long axis direction. You can see that it is.
- the length of these crystal grains in the short axis direction is about 1.5 to 2 tm, and the size in the long axis direction is about 0.7 to 1.5 xm.
- Figure 4A shows the temperature dependence of the growth rate of silicon crystals
- Figure 4B shows the temperature dependence of the nucleation rate of crystal growth.
- the vertical axis of FIG. 4 A represents the growth rate in the unit of "mZ s”
- the vertical axis in FIG. 4 B represents a nucleation rate in the unit of "l Z cm 3 's”
- the horizontal axis represents the temperature of both
- the unit is represented by “K”.
- the graphs in Fig. 4 ⁇ and Fig. 4 ⁇ are from the data collection of the 2nd FEM Seminar of the 2nd Simulation Integrated System Subcommittee of the Japan Society for Technology of Plasticity held on July 14, 1999. This is obtained from the technique of "Micro-analysis of dynamic crystal growth process of polycrystals" by Ohji Ichijima (Sumitomo Heavy Industries, Ltd.) published on page 27, pages 27-32.
- the growth rate is 0 at the melting point of single-crystal silicon (1683 K), and the growth rate increases as the temperature decreases. Near the temperature of 150 ° C., the growth rate shows the maximum value. Therefore, the lower the temperature of the molten silicon, the faster the growth rate.
- the growth rate also depends on the temperature gradient at the interface between the solid phase and the liquid phase. If the temperature gradient is steep, the growth rate is high.
- the nucleation rate increases as the temperature decreases from the melting point of silicon, and reaches a maximum value near the temperature of 600 ⁇ °.
- the band-like region 7 shown in FIG. 3 is considered to be a region where the nucleation rate is low and the growth rate is high, and the temperature and the temperature gradient at the solid-liquid interface are suitable.
- the region 12 between the band-shaped region 7 and the amorphous region 9 has a higher nucleation rate because the temperature is lower than that of the band-shaped region 7, and the growth rate is low because the temperature gradient at the solid-liquid interface is gentle. It is considered a late region. In this region, many nuclei were generated before growing into large crystals, so it is probable that the crystal grains could not be enlarged.
- nuclei are generated explosively due to the temperature drop, and it is considered that the nucleation is more dominant than the growth rate.
- crystal growth in the band-like region 7 is hindered by newly generated nuclei, and crystal growth stops. It is considered that the portion where the crystal growth has stopped corresponds to the boundary between the band-shaped region 7 and the microcrystalline region 8.
- crystal growth from nuclei generated inside the molten layer is considered to be dominant. It is considered that large crystal grains are formed at the boundary between the region where heterogeneous growth is dominant and the region where homogenous growth is dominant.
- the molten portion of silicon has a suitable temperature gradient and temperature with a high growth rate and a low nucleation rate. If the temperature gradient at the position of the band-like region 7 shown in FIG. 2A is steep, the region where a suitable temperature is maintained becomes narrow, and it is difficult to form large crystal grains. In order to form large crystal grains, it is preferable to make the gradient of the pulse energy density distribution in the vicinity of the band-like region 7 gentle.
- the gradient of the pulse energy density distribution is too steep, the nucleation rate increases. On the other hand, if the gradient of the pulse energy density distribution is too gentle, the growth rate becomes slow. Therefore, in order to obtain a suitable temperature at which the growth rate is high and the nucleation rate is low and a temperature gradient at the solid-liquid interface, it is considered that the gradient of the pulse energy density distribution has a suitable range that is neither too steep nor too gentle. .
- Figure 5A shows the relationship between crystal grain size and beam width on the surface of the workpiece.
- the horizontal axis represents the beam width in the unit of “m”, and the vertical axis represents the size of the crystal grains in the unit of “zm”.
- the size of the crystal grain was calculated using a crystal growth evaluation program disclosed in JP-A-2001-297983.
- the object to be processed is a 100-nm-thick silicon oxide film and a 50-nm-thick amorphous silicon film formed thereon.
- the wavelength of the pulse laser beam is 527 nm
- the pulse width (half width) is 140 ns
- the width of the beam incident area is 1 m outside and inside the position where the pulse energy density is half the peak value.
- the simulation was performed on a region having a width of 6 nm and a width of 5 nm. This is because the gradient of the pulse energy density distribution shows a maximum at a position where the value is half of the peak value, and large crystal grains are formed in this region.
- the intensity distribution in the minor axis direction of the beam incident area was a Gaussian distribution.
- Four beam widths of 5.0 m, 8.3 nm, 16.7 zm, and 83. O ⁇ m For each of, a simulation was performed with various peak intensities, and the size of the crystal grain under the condition that the maximum crystal grain was obtained was taken as the size of the crystal grain at the beam width.
- the maximum value of the pulse energy density is 1 l O OmJZcm 140 Om J / cm 2 .
- the maximum crystal grains were obtained under the conditions of 150 Om J / cm 2 and 150 Om J / cm 2 .
- FIG. 5B shows the relationship between the gradient of the pulse energy density distribution at the position showing half the peak intensity and the size of the crystal grains. For each evaluation point in Fig. 5A, the slope of the pulse energy density distribution was calculated, and the graph in Fig. 5B was created.
- the crystal grains gradually increase. This is thought to be due to the higher crystal growth rate.
- the gradient of the pulse energy density distribution is around 170 mJ / cm 2 / m, the crystal grain size shows the maximum value, and when the gradient is made larger than that, the crystal grain becomes smaller. This is thought to be because the gradient of the pulse energy density becomes steeper, the temperature gradient at the solid-liquid interface also becomes steeper, and the cooling rate increases due to the lateral heat diffusion. That is, it is considered that a sufficient crystal growth time is not secured, and a large number of nuclei are generated before the crystal grows large.
- the gradient at the position where the pulse energy density was 50 OmJX cm 2 was 13 mJ / cm 2 Z m.
- the size of the crystal grains in the short axis direction in the belt-shaped region 7 shown in FIG. 3 is about 1.5 to 2 ⁇ m, which is almost the same as the tendency of the simulation result shown in FIG. 5B. Even when the gradient was set to 18 mJ / cm 2 Zm, a tendency almost similar to the simulation result shown in FIG. 5B was obtained. If the gradient at a pulse energy density of 500 mJ / cm 2 is 1 Om JZcm 2 / m or more, a tendency similar to the simulation result shown in FIG. 5B will be obtained.
- the position of the band-like region 7 shown in FIGS. 2A and 2B (more precisely, the position outside the band-like region 7)
- the slope of the pulse energy density distribution at the edge) is 280mJZcm ..
- the gradient is preferably set to 1 OmJZcmSZm or more. Similar simulations were performed with the thickness of the amorphous silicon film set to 100 nm, and almost the same tendency was obtained as when the thickness was 5 Onm.
- a relatively high-intensity portion of the foot of the laser beam enters a region 12 where crystal grains are randomly distributed.
- the region 12 is irradiated with a relatively high-intensity laser beam, the temperature of this region rises. For this reason, the temperature of the band-shaped region 7 and the temperature gradient at the solid-liquid interface satisfy the conditions suitable for forming large crystal grains. In order to obtain a sufficient effect of increasing the crystal grain, it is preferable that the width W of the region 12 be 15 or more.
- FIG. 6 shows the relationship between the crystal grain size and the pulse width.
- the horizontal axis represents the pulse width in units of “ns”
- the vertical axis represents the size of crystal grains in units of “m”.
- the crystal grain size was calculated using the above-described crystal growth evaluation program.
- the object to be processed and the wavelength of the pulsed laser beam are the same as those described with reference to FIG.
- the beam width on the surface of the object was set to 16.7 m.
- the simulation method is the same as the method described in FIG.
- the longer the pulse width the larger the crystal grains formed. This is presumably because as the pulse width becomes longer, the temperature drop becomes gentler, and as a result, the molten portion is maintained at a suitable temperature and the time becomes longer.
- the pulse width is increased under certain conditions of the pulse energy, the peak intensity of the pulsed laser beam decreases, and a sufficient power density cannot be maintained. Therefore, the upper limit of the pulse width is limited by the output characteristics of the laser light source used.
- the pulse width is generally 7 Ons or less.
- all solid-state lasers such as an Nd: YLF laser have a pulse width of 20 to 30 ns or a pulse width of 100 ns or more.
- FIG. 7 shows an example of the waveform of a laser beam incident on the object to be processed.
- the horizontal axis represents the elapsed time, and the vertical axis represents the intensity of the laser beam.
- the first pulse laser beam S1 is incident, and at time t2, the second pulse laser beam S2 is incident.
- the pulse widths (half-width) of the first and second shots of the pulsed laser beam are PW1 and PW2, respectively.
- FIG. 7 shows a case where the peak intensity of the second shot pulsed laser beam is smaller than the peak intensity of the first shot pulsed laser beam, but both may be the same.
- the amorphous silicon film is melted by the injection of the first shot pulse laser beam S1 shown in FIG. Nuclei are generated as the temperature decreases, and crystals grow from the nuclei. Before cooling to a temperature that increases the nucleation rate, a second pulsed laser beam S 2 is injected and reheated. Thus, nucleation can be suppressed and crystal growth can be continued. Therefore, large crystal grains can be formed.
- the pulsed laser beam S2 of the second shot may be incident before the portion melted by the incidence of the first shot is completely solidified.
- the delay time from the first shot laser beam incidence to the second shot laser beam incidence may be set to about 300 to 150 ns.
- the delay time can be controlled more easily than when an excimer laser is used.
- the crystal grains once formed are less likely to melt than the amorphous state. For this reason, once formed crystal grains are unlikely to be re-melted by the irradiation of the second shot pulsed laser beam S2.
- the crystal grain size is about 2 ⁇ m. It was lm.
- the first shot of the peak value of the Parusueneru formic density 1 3 0 0 m JZ cm 2, 2 shot pulse energy density ..
- the size of crystal grains was about 4.4 xm. In this way, by providing a two-shot pulsed laser beam with a delay time provided, the crystal grains can be enlarged.
- the method of irradiating the pulsed laser beam of the second shot before the part melted by the incidence of the first shot is solidified is called a double pulse method. More generally, a method of irradiating a pulsed laser beam of two or more shots before molten silicon solidifies is referred to as a multi-pulse method.
- a mask for making the intensity distribution of the laser beam top flat is not used. For this reason, the energy use efficiency of the laser beam can be improved.
- the method of the first embodiment it is possible to form a crystal grain row in which the crystal grains are arranged in a row in the first direction.
- the average size of crystal grains in a direction orthogonal to the first direction can be set to 1.5 or more.
- FIGS. 8A to 8G shows a cross section of the silicon film, and the horizontal direction in the figure corresponds to the short axis direction of the incident area of the pulsed laser beam.
- the two belt-like regions 7 are positioned in the major axis direction (perpendicular to the plane of FIG. 8). A large number of continuous crystal grains are formed. In a region 8 sandwiched between the two band-like regions 7, fine crystal grains are formed.
- the width of each of the band-shaped regions 7 is, for example, 4 m.
- FIGS. 5A and 5B it is sufficiently possible to form crystal grains having a size of about 4 m by optimizing the conditions of laser beam incidence.
- FIG. 8B shows the crystallization state after the second irradiation has been performed by moving the incident position of the laser beam by 15 zm in the minor axis direction. For example, if the beam width is 100 m and the travel distance is 15 m, the overlap ratio will be 85%. ⁇
- a shaped region 20 is formed.
- the width of the band-shaped region 20 is 4 m.
- the amorphous silicon film, the fine crystal grains, and the small crystal grains in the region sandwiched between the two band-shaped regions 20 are melted, but the large crystal grains in the band-shaped region 7 are hardly melted as described later.
- the crystal grains in the band-shaped region 7 partially melt, but a part thereof remains as a crystal. As the temperature decreases, the crystal grains remaining in the band-like region 7 become seed crystals, and crystal growth occurs.
- the length of the crystal growing on both sides of the band-shaped region 7 is about 4 m. Therefore, a polycrystalline region 7a having a width of about 12 / m is formed around the band-like region 7 located on the front side in the moving direction.
- the width of the microcrystalline region 15 between the band-shaped region 7a and the band-shaped region 20 located on the front side in the movement direction is about 7. Since the amorphous silicon film, the fine crystal grains, and the small crystal grains around the band-shaped region 7 located on the rear side in the moving direction do not melt, no crystal growth occurs.
- Figure 8C shows the crystallization state after the laser beam incident position is further moved by 15 m in the short axis direction and the third irradiation is performed.
- a band-shaped region 21 in which crystal grains are connected is formed.
- the width of the band-shaped area 21 is 4 m. Furthermore, crystal growth occurs in the band-shaped region 7a and the crystal grains in the band-shaped region 20 located on the front side in the moving direction as seed crystals.
- a crystal of about 4 m grows from the belt-shaped region 7a toward the rear side in the moving direction. At the same time, a crystal of about 4 m grows from the belt-like region 20 toward the front side in the moving direction.
- a region 15 sandwiched between the band-shaped region 7a and the band-shaped region 20 crystal growth occurs from both sides toward the center. Since the width of the region 15 is about 7 / m, at the time of growing 3.5 m from each side, the crystal grains collide with each other and the crystal growth stops.
- a band-shaped region 7b having a width of 19.5 zm including the band-shaped region 7a is formed, and a band-shaped region 20a having a width of 11.5 / m including the band-shaped region 20 is formed.
- a number of crystal grains connected in the long axis direction are formed in the belt-like regions 7b and 20a. Grain boundaries are arranged along the center line 16 of the region 15. Note that the crystal grains may collide with each other. Therefore, a mountain-shaped convex portion is formed at the position of the center line 16.
- FIG. 8D shows the crystallization state after the laser beam incident position is further moved in the short axis direction by 15 and the fourth irradiation is performed.
- a band-shaped region 22 is formed at a position where the band-shaped region 21 is moved forward by 15 / zm in the moving direction.
- the crystal grains in the band-shaped region 20a as seed crystals, crystals grow on the front side in the moving direction, and the crystal grains in the band-shaped region 21 as seed crystals, and crystals grow on both sides thereof.
- a band-shaped region 20b having a width of 15 im and a band-shaped region 21a having a width of 11.5 / zm are formed.
- 8E to 8G show the crystallization state after the laser beam incident position is moved by 1 ⁇ ⁇ ⁇ in the short axis direction and the fifth to seventh irradiations are performed.
- a new band-shaped region 23 is generated, and at the same time, the band-shaped regions 21a and 22 are expanded, and the band-shaped regions 21b and 22a are formed.
- the band-shaped regions 22a and 23 are expanded, and the band-shaped regions 22b and 23a are formed.
- the band-shaped region 23a is expanded, and the band-shaped region 23b is formed.
- FIG. 9 shows a sketch of an SEM photograph of the polycrystalline film produced by the method shown in FIG. Multiple strips 25 are observed.
- Each band-like region 25 has a width of about 15 im, and in the band-like region 25, a large number of crystal grains connected in the major axis direction are formed.
- a mountain-shaped projection 26 is formed at the boundary between the belt-like regions 25 adjacent to each other.
- FIG. 10 shows the relationship between the length of crystal growth per irradiation and the required overlap ratio.
- the horizontal axis represents the length of crystal growth per irradiation in the unit of “m”, and the vertical axis represents the overlap ratio in the unit of “%”.
- the overlap ratio may be set to 70% or more. It can be seen that the shorter the length of crystal growth per irradiation becomes, the higher the variation rate required for polycrystallizing the entire surface becomes.
- the center line 16 of the microcrystalline region 15 is irradiated with the laser beam until the crystal grains growing from both sides of the microcrystalline region 15 shown in FIG.
- the overlap ratio may be set so as to fall within the silicon melting region.
- Figure 11 shows the wavelength dependence of the light absorption coefficient of amorphous silicon and single crystal silicon.
- the horizontal axis represents the wavelength in the unit of "nm”, is the ordinate and open circles in.
- View representing the absorption coefficient in the unit of "X 1 0 7 cm-, the absorption coefficient of the absorption coefficient and amorphous silicon, respectively monocrystalline silicon Is shown.
- the absorption coefficient of amorphous silicon is larger than the absorption coefficient of single crystal silicon in the wavelength region of about 350 nm or more.
- the absorption coefficient of amorphous silicon is at least one order of magnitude greater than that of single crystal silicon.
- the wavelength 34 is used to preferentially melt the amorphous region 9, the random distribution region 12 and the microcrystalline region 8 without melting the large crystal grains in the band region 7 shown in FIG. It is preferable to use a pulse laser beam of 0 nm or more. If the wavelength is too long, the absorption coefficient will decrease. Preferably, the wavelength of the beam is 900 nm or less.
- the absorption coefficient of amorphous silicon is higher than the absorption coefficient in the wavelength range of 340 to 900 nm. For this reason, absorption occurs only near the surface of the amorphous silicon film, and a temperature gradient occurs in the thickness direction.
- the laser beam penetrates into a relatively deep region of the amorphous silicon film and is heated almost uniformly in the thickness direction. Therefore, higher quality crystals can be formed.
- Figure 12A shows the relationship between the pulse energy density distribution in the minor axis direction of the irradiated laser beam and the region to be polycrystallized.
- Microcrystals are formed in the region 35 where the portion having the highest pulse energy density is incident, and band-shaped regions 3OA and 30B in which large crystal grains are connected in the long axis direction are formed on both sides thereof.
- the beam width is set such that the width of the region 35 where the microcrystal grains are formed is substantially equal to the width of each of the band-shaped regions 30A and 30B.
- the second laser irradiation is performed by moving the incident position of the laser beam in the minor axis direction by a distance equal to the width of the band-shaped region 3OA.
- a band-shaped region 31A in which large crystal grains are connected is formed between the band-shaped regions 3OA and 30B in which crystal grains have already been formed.
- a band-shaped region 31B is formed in front of the band-shaped region 30B located on the front side in the moving direction.
- the two irradiations form four strips 30A, 31A, 30B, and 3IB.
- the crystal grains in the belt-like regions adjacent to each other are in contact with each other.
- the entire surface can be polycrystallized. Note that, depending on the temperature conditions, crystal grains do not grow from nuclei generated in the region 35 shown in FIG. 12A, but rather crystal grains in the band-shaped regions 30 A and 30 B on both sides. As a seed crystal, crystal growth may occur.
- Figure 13A shows the relationship between the pulse energy density distribution in the minor axis direction of the irradiated laser beam and the region to be polycrystallized.
- band-shaped regions 36 A and 36 B in which large crystal grains are connected in the longitudinal direction are formed. Since the beam width is narrow, the crystal grains generated from the nuclei in the band-shaped region 36A and the crystal grains generated from the nuclei in the band-shaped region 36B come into contact with each other. Grain boundaries are arranged along the line 38 where they contact. .
- the laser beam incident position is moved in the short axis direction by the total width of the band-shaped regions 36 A and 36 B, and the second irradiation is performed.
- strip-shaped regions 37A and 37B that are in contact with each other are formed.
- the band-shaped region 37A located on the rear side in the moving direction contacts the band-shaped region 36B formed on the front side in the moving direction formed by the first irradiation.
- Crystal grains can be formed by setting the pulse energy density distribution of the pulsed laser beam irradiated in the third and fourth embodiments to the suitable shape described in the first embodiment.
- crystal grains can be made larger.
- FIG. 14 shows a cross-sectional view near the laser beam incident position of the object 1 and an example of the distribution of the pulse energy density in the minor axis direction of the beam cross section.
- the pulse energy density is obtained by dividing the pulse energy by the area of the beam cross section. Strictly speaking, the pulse energy density obtained by this calculation is the average value in the beam cross section. Since the light intensity within the beam cross section is not constant, the pulse energy density is not constant either. When the light intensity distribution is approximated by a Gaussian distribution, the pulse energy density distribution is also approximated by a Gaussian distribution.
- the object to be processed is a silicon oxide film 3 and an amorphous silicon film on a glass substrate 2, as in the case of the first embodiment described with reference to FIG. 2A.
- This is a laminated substrate on which the condenser film 4 is laminated.
- the incident position of the pulsed laser beam moves to the right in Fig. 14.
- a part of the laser beam that has passed through the homogenizer 72 shown in FIG. 1 is shielded by the light shielding plate 18 and enters the amorphous silicon film 4 via the imaging optical device 19.
- the light shielding plate 18 shields light at the foot of the pulse energy density distribution in the minor axis direction of the beam cross section.
- the imaging optical device 19 forms a beam cross section at the position where the light shielding plate 18 is arranged on the surface of the amorphous silicon film 4.
- the imaging magnification is, for example, 1 ⁇ .
- the distribution of the pulse energy density in the minor axis direction of the pulse laser beam on the surface of the amorphous silicon film 4 is approximated by a Gaussian distribution.
- the pulse energy density is strong at the center and weakens as it approaches the edge.
- the distribution of the pulse energy density does not necessarily have to be a Gaussian distribution, but may be a distribution that is generally strong at the center and weakens toward the edge.
- the light intensity did not immediately become 0 at the edge of the beam cross section shielded by the light shielding plate 18, and the beam cross section extended to about 6 m outside the shielded position.
- the edge of the beam cross section was located at a position where the light intensity became 20% of the peak value.
- a pulse laser beam having such a pulse energy density distribution is incident on the amorphous silicon film 4 for one shot.
- the region irradiated with the laser beam having a pulse energy density higher than the threshold value at which the amorphous silicon film 4 is completely melted is melted. If the pulse energy density E L is the threshold or more, the entire area irradiated with the pulse laser beam is melted. As the melt cools, crystals grow from the edge of the melt to the inside.
- a large number of crystal grains 100a arranged in the longitudinal direction of the beam cross section are formed on the rear edge of the pulse laser beam incident position in the moving direction, and Many crystal grains 101 a are formed on the side edge.
- Microcrystalline grains are formed in a region between the region where the crystal grain 100 a is formed and the region where the crystal grain 101 a is formed, as in the region 8 shown in FIG. .
- the length of the growing crystal depends on the temperature of the melt and the temperature gradient at the solid-liquid interface.
- the temperature and temperature gradient at the rear edge are different from the temperature and temperature gradient at the front edge. Therefore, the lengths of the crystals grown from both edges of the melted region are different from each other.
- the crystal grains 100 a formed at the rear edge are replaced with the crystal grains 101 a formed at the front edge. Larger than. For example, what is the lateral dimension of the crystal grain 100a formed on the rear edge? could be up to 8.
- the incident position of the pulsed laser beam is moved in the short axis direction of the beam cross section, and one pulse of the pulsed laser beam is incident.
- the moving distance of the incident position is such that the rear edge of the cross section of the newly irradiated pulse laser beam is in contact with or overlaps the crystal grain 100a.
- the crystal grains formed at the front edge during the previous irradiation are melted by the current irradiation.
- Fig. 15B As shown in Fig. 15B, at the rear edge of the region melted by this irradiation, crystals grow laterally using the crystal grain 100a as a seed crystal and include the crystal grain 100a. Very large crystal grains 100 b are formed. When the rear edge of the beam cross section of the pulsed laser beam irradiated this time touches the crystal grain 100a, the lateral dimension of the crystal grain 100b is about two times the dimension of the crystal grain 100a. Double to 14 to 16 xm.
- the pulse laser beam irradiation is repeated while moving the incident position of the pulse laser beam so that the area irradiated in the previous shot and the area irradiated in the current shot partially overlap.
- the moving distance is such that the rear edge of the beam section of the pulse laser beam to be newly irradiated touches or overlaps the rear crystal grain formed by the previous irradiation.
- the crystal grains grow laterally, and large crystal grains 100 c are formed.
- the small crystal grains 101 b formed on the front edge of the beam cross section are melted and extinguished by the subsequent irradiation of the pulsed laser beam.
- a crystal grows from the rear edge of the beam section defined by the light shielding plate 18.
- the band-shaped region 7 where large crystal grains occur is meandering.
- the continuous band-like region of the crystal grain 100a does not meander, and is substantially straight. Along the shape. Therefore, at the time of the second irradiation, positioning can be easily performed such that the rear edge of the beam cross section is in contact with the continuous band-shaped region of the crystal grains 100a.
- the direction of crystal growth is also aligned with the direction perpendicular to the major axis of the beam cross section.
- the current direction of the active element to be formed and the direction of crystal growth are made parallel to suppress a decrease in carrier mobility due to crystal grain boundaries. it can.
- the incident position is moved every time one pulse of the pulsed laser beam is incident.
- two pulsed laser beams are incident on the same position.
- a double pulse method or a multipulse method may be used. Thereby, the formed crystal grains can be enlarged.
- the preferred area of the pulse energy density distribution shown in Fig. 14 that should be shielded is evaluated by changing the size (width) of the light shield area. It can be determined by conducting experiments. Hereinafter, the results of the evaluation experiments actually performed will be described.
- the laser beam emitted from the laser light source was formed into a long beam having a beam cross section of 100 tm in width and 17 mm in length. Both sides of the beam cross section in the width direction were shielded by a light-shielding plate to form a cross section having a width of 22 m, and the beam cross section was imaged on the surface of the amorphous silicon film.
- the width of the beam cross section is the half width of the light intensity distribution.
- the first shot and the second shot of pulse rates one Zabimu, a pulse energy density in the amorphous silicon film surface, and each 5 5 O m JZ cm 2 and 5 OO m JZ cm 2, the delay time A double-pulse method with 100 ns was adopted.
- the tail portion where the pulse energy density is equal to or less than E H is shielded by the light shielding plate 18,
- the tail portion where the pulse energy density is equal to or less than EL is shielded by the light shielding plate 18.
- crystal grains 110b and 111b are formed. Since relatively large crystal grains 110a are hard to melt, they hardly melt by the irradiation after the next irradiation.
- the crystal grain 11 Ob grows from the front edge of the melted region toward the rear side (the crystal grain 110a side). The growth stops when the tip of the crystal growth reaches the crystal grain 110a.
- the moving pitch of the incident position of the pulsed laser beam can be longer than the width of the crystal grain 110a.
- relatively large crystal grains 110a to 110e are formed.
- relatively small crystal grains 11 1 c are formed at the rear edge of the beam cross section.
- the rear edge of the beam cross section is located inside the relatively large crystal grains 110a to 110e, so the molten portion is near the rear edge. Does not occur.
- a clear boundary is formed between the continuous band-shaped region of the crystal grain 110a and the continuous band-shaped region of the crystal grain 11 Ob. .
- the position of this boundary is determined artificially by the light shielding plate 18.
- the light shielding plate 18 For example, when an active element is formed on a polycrystalline silicon thin film, it is possible to arrange the boundaries of crystal grains so that the active element does not cross the boundaries of crystal grains. As described above, it is also possible to cover the entire surface of the substrate with the band-shaped region as shown in FIG.
- the laser beam emitted from the laser light source is shaped into a long beam with a beam cross section of 100 m wide and 17 mm long.
- the edge of the beam cross section on the front side in the scanning direction was shielded from light by a light shielding plate to form a cross section of 55 m in width, and this beam cross section was imaged on the surface of the amorphous silicon film.
- a pulse energy density in the amorphous silicon film surface, their respective and 710m JZcm 2 and 640MJZcm 2 double pulses of the delay time 200 ns The method was adopted.
- the width of the crystal grain 110a formed on the beam cross section on the front side in the running direction became 5.4 zm.
- a 12 xm wide band-like region in which crystal grains continued in the longitudinal direction of the beam cross section was formed.
- the crystal grains in the band-like regions adjacent to each other were in contact with each other at the boundary of the band-like region, and the entire surface could be polycrystallized.
- the width of crystal grains 110a formed in one irradiation is 5.4 zm '
- the width of the finally formed band-shaped area is 12 This is because the crystal grains with a width of 5.4 / m are used as seed crystals and subsequent irradiation causes lateral crystal growth. This growth process is the same as the crystal growth process described in FIGS. 8A to 8G.
- the double pulse method was adopted.
- the delay time from the input of the first shot pulse laser beam to the input of the second shot pulse laser beam is 100 to 1000 ns.
- This preferable delay time is slightly shorter than the case where the light shielding plate is not used. This is because the slope of the light intensity distribution is steep on both sides of the beam cross section, and the solidification rate is faster than when no light shielding plate is used.
- a seventh embodiment will be described.
- a part of the laser beam is shielded by the light shielding plate so that the light intensity distribution (or pulse energy density distribution) becomes asymmetrical in the width direction of the beam cross section.
- the light may be shielded so that When the light intensity distribution is symmetric, crystal grains having substantially the same size are formed at the front edge and the rear edge in the scanning direction. Therefore, the second embodiment described with reference to FIGS. 8A to 8G, the third embodiment described with reference to FIGS. 12A and 12B, or FIGS. Polycrystallization of the amorphous silicon film can be performed by a method similar to the method according to the fourth embodiment described with reference to 13B.
- the beam cross section at the position where the light shielding plate is arranged is imaged on the surface of the amorphous silicon film.
- the light shielding plate may be arranged close to the amorphous silicon film.
- the distance between the light shielding plate and the amorphous silicon film may be, for example, about 0.1 mm.
- a part of the laser beam is shielded by the light shielding plate to form a laser beam having an asymmetric light intensity distribution in the width direction of the beam cross section.
- the light intensity distribution may be asymmetric.
- a Dara radiation filter having a dot pattern of chromium (Cr) or the like arranged on the surface of quartz glass may be arranged in the optical path.
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Cited By (5)
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JP2005045209A (ja) * | 2003-07-09 | 2005-02-17 | Mitsubishi Electric Corp | レーザアニール方法 |
JP2008091509A (ja) * | 2006-09-29 | 2008-04-17 | Fujifilm Corp | レーザアニール技術、半導体膜、半導体装置、及び電気光学装置 |
JP2014528162A (ja) * | 2011-09-01 | 2014-10-23 | アプライド マテリアルズ インコーポレイテッドApplied Materials,Incorporated | 結晶化法 |
JP2020181923A (ja) * | 2019-04-26 | 2020-11-05 | 株式会社日本製鋼所 | 半導体膜の製造方法 |
JP2020537357A (ja) * | 2017-10-13 | 2020-12-17 | ザ トラスティーズ オブ コロンビア ユニヴァーシティ イン ザ シティ オブ ニューヨーク | スポットビーム及びラインビーム結晶化のためのシステムおよび方法 |
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KR100713895B1 (ko) * | 2006-04-06 | 2007-05-04 | 비오이 하이디스 테크놀로지 주식회사 | 다결정막의 형성방법 |
KR102657831B1 (ko) * | 2016-01-08 | 2024-04-16 | 더 트러스티이스 오브 콜롬비아 유니버시티 인 더 시티 오브 뉴욕 | 스폿 빔 결정화를 위한 방법 및 시스템 |
DE102017109809B4 (de) | 2016-05-13 | 2024-01-18 | OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung | Verfahren zur Herstellung eines Halbleiterchips |
DE102017109812A1 (de) | 2016-05-13 | 2017-11-16 | Osram Opto Semiconductors Gmbh | Licht emittierender Halbleiterchip und Verfahren zur Herstellung eines Licht emittierenden Halbleiterchips |
DE102017108949B4 (de) | 2016-05-13 | 2021-08-26 | OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung | Halbleiterchip |
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- 2003-10-14 CN CNB2003801024215A patent/CN100378919C/zh not_active Expired - Fee Related
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Publication number | Priority date | Publication date | Assignee | Title |
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JP2005045209A (ja) * | 2003-07-09 | 2005-02-17 | Mitsubishi Electric Corp | レーザアニール方法 |
JP2008091509A (ja) * | 2006-09-29 | 2008-04-17 | Fujifilm Corp | レーザアニール技術、半導体膜、半導体装置、及び電気光学装置 |
KR101372340B1 (ko) | 2006-09-29 | 2014-03-25 | 후지필름 가부시키가이샤 | 레이저 어닐 기술, 반도체 막, 반도체 장치, 및 전기 광학장치 |
JP2014528162A (ja) * | 2011-09-01 | 2014-10-23 | アプライド マテリアルズ インコーポレイテッドApplied Materials,Incorporated | 結晶化法 |
US10074538B2 (en) | 2011-09-01 | 2018-09-11 | Applied Materials, Inc. | Methods for crystallizing a substrate using a plurality of laser pulses and freeze periods |
JP2020537357A (ja) * | 2017-10-13 | 2020-12-17 | ザ トラスティーズ オブ コロンビア ユニヴァーシティ イン ザ シティ オブ ニューヨーク | スポットビーム及びラインビーム結晶化のためのシステムおよび方法 |
JP7335236B2 (ja) | 2017-10-13 | 2023-08-29 | ザ トラスティーズ オブ コロンビア ユニヴァーシティ イン ザ シティ オブ ニューヨーク | スポットビーム及びラインビーム結晶化のためのシステムおよび方法 |
JP2020181923A (ja) * | 2019-04-26 | 2020-11-05 | 株式会社日本製鋼所 | 半導体膜の製造方法 |
Also Published As
Publication number | Publication date |
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TW200416835A (en) | 2004-09-01 |
JP4211939B2 (ja) | 2009-01-21 |
CN101145518A (zh) | 2008-03-19 |
KR100685141B1 (ko) | 2007-02-22 |
CN100378919C (zh) | 2008-04-02 |
CN1708831A (zh) | 2005-12-14 |
CN100514561C (zh) | 2009-07-15 |
JPWO2004040628A1 (ja) | 2006-03-02 |
KR20050059322A (ko) | 2005-06-17 |
TWI240957B (en) | 2005-10-01 |
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