CN1186802C - Surface Planarization of Silicon Thin Films During and After Processing by Sequential Lateral Solidification Method - Google Patents

Abstract

A system and method for reducing the surface roughness of polycrystalline or single-crystal thin films produced by a sequential transverse curing process are disclosed. In one configuration, the system includes an excimer laser (110) for generating a plurality of excimer laser pulses with predetermined flux amounts; an energy density modulator (120) for controllably adjusting the flux amounts of the excimer laser pulses to a level below that required to completely melt the thin film; a beam homogenizer (144) for homogenizing the adjusted laser pulses in a predetermined plane; a sample stage (170) for receiving the homogenized laser pulses to perform partial local melting of the polycrystalline or single-crystal thin film corresponding to the laser pulses; a translation device for controllably translating the relative position of the sample stage (170) with respect to the laser pulses; and a computer (110) for coordinating the generation and flux amount adjustment of the excimer pulses with the relative position of the sample stage (170) to process the polycrystalline or single-crystal thin film by sequential translation of the sample stage (170) with respect to the laser pulses.

Description

Surface Planarization of Silicon Thin Films During and After Processing by Sequential Lateral Solidification Method

technical field

The present invention relates to semiconductor processing technology, and more particularly to semiconductor processing that can be performed at low temperatures.

Background technique

In the field of semiconductor processing, several attempts have been made to convert amorphous silicon films into polycrystalline films using laser light. Traditional excimer laser annealing techniques are outlined in "Crystalline Si Film for Integrated Active-Matrix Liquid-Crystal Display" (11 MRS Bulletin 39 (1996)) by James Im et al. In systems for performing excimer laser annealing, an excimer laser beam is formed into a long beam, typically up to 30 cm in length and 500 microns or more in width. A shaped beam is scanned over a sample of amorphous silicon to cause it to melt and form polysilicon as the sample resolidifies.

For several reasons, the use of conventional excimer laser annealing techniques to produce polycrystalline or monocrystalline silicon can be problematic. First, the silicon produced during this process is typically small grains with an arbitrary microstructure, and/or the grains are non-uniform in size, which results in poor and non-uniform devices, resulting in lower yields. Second, the processing techniques required to achieve acceptable performance levels need to keep polysilicon production throughput low. In addition, processing typically requires controlled atmospheres and preheating of amorphous silicon samples, further reducing productivity. Finally, the fabricated films often exhibit unacceptable surface roughness, which can also cause problems for the performance of microelectronic devices.

There is a need in the art to produce higher quality polysilicon and monocrystalline silicon thin films at greater throughput rates. At the same time, there is a need for a fabrication technique that reduces the surface roughness of these polycrystalline and monocrystalline silicon thin films so that they can be used to fabricate higher quality devices such as flat panel displays.

Contents of the invention

An object of the present invention is to provide a technique for planarizing the surface of polycrystalline and monocrystalline silicon thin film semiconductors.

Another object of the present invention is to provide a surface planarization technique that can be applied as a post-processing step to polycrystalline and monocrystalline silicon thin film semiconductors produced during a sequential lateral solidification process.

It is a further object of the present invention to provide a surface planarization technique that can be applied as a processing step during the production of polycrystalline and monocrystalline silicon thin film semiconductors in a sequential lateral solidification process.

Yet another object of the present invention is to provide a technique for manufacturing high-quality semiconductor devices that can be used in the manufacture of displays and other products.

To accomplish these and other objects that will become apparent with reference to the description that follows, the present invention provides systems and methods for reducing the surface roughness of polycrystalline or monocrystalline thin films previously produced by a sequential lateral solidification process. In one configuration, the system includes an excimer laser for generating a plurality of excimer laser pulses with a predetermined fluence; for controllably adjusting the fluence of the excimer laser pulses such that the fluence is below An energy density adjuster for the fluence required to completely melt the film; a beam homogenizer for homogenizing the adjusted laser pulse in a predetermined plane; for receiving the homogenized laser pulse to perform polycrystalline or The portion of the single crystal thin film corresponds to a sample stage that is locally melted by the homogenized laser pulse; a translation device for controllably translating (translate) the relative position of the sample stage relative to the homogenized laser pulse; A computer that coordinates the generation of excimer pulses and fluence adjustment of relative positions to process polycrystalline or single crystal thin films by sequential translation of the sample stage relative to the homogenized laser pulses. The excimer laser is preferably an ultraviolet excimer laser for generating ultraviolet excimer laser pulses.

In one configuration, a beam homogenizer can be used to shape the laser pulses into a tophat distribution along the x and y directions. A fluence modulator can be used to decay the fluence of the excimer laser pulse to approximately 25% to 75% of the complete melting threshold of polycrystalline or single crystal thin films.

The translation stage advantageously comprises an X-direction translation section and a Y-direction translation section, each section being coupled to the computer and to each other and allowing movement in two orthogonal directions relative to the homogenized laser pulses, each section being computer controllable, to controllably translate the sample in the two orthogonal directions. In addition, a beam homogenizer can be used to shape the modulated laser pulses into a top-hat distribution in the x and y directions, and a translation device can be used to translate the polycrystalline or single crystal thin films, whereby sequentially homogenized laser pulses are incident on slightly overlapping regions of polycrystalline or single crystal thin films along these two directions.

In another configuration, the present invention provides systems and methods for processing amorphous silicon thin film samples into polycrystalline or single crystal silicon thin films with reduced surface roughness. In one configuration, the method includes forming a rigid capping layer on an amorphous silicon film sample thick enough to withstand shrinkage and expansion during melting and re-solidification of the silicon film in a sequential lateral solidification process. The method also includes generating a sequence of excimer laser pulses; controllably adjusting each excimer laser pulse in the sequence to a predetermined fluence; averaging each adjusted laser pulse in the sequence in a predetermined plane ; mask the portion of each fluence-controlled homogenization laser pulse in the sequence to produce a fluence-controlled pulse train with patterned sub-beams (beamlets); The sub-beam sequence irradiates the amorphous silicon thin film sample to partially melt it; the sample is controllably sequentially translated with respect to each of said fluence-controlled pulses with the patterned sub-beam, thereby turning the amorphous silicon thin film sample processing to a single crystal or polycrystalline silicon film with reduced surface roughness; and removing the capping layer from the processed single crystal or polycrystalline silicon film.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and serve to explain the principles of the invention.

Figure overview

Figure 1 is a functional diagram of a system for performing a preferred sequential lateral curing process for implementing the preferred process of the present invention;

Figure 2 is a graph showing the surface profile of a typical film that has been processed by the sequential lateral curing system of Figure 1;

3 is a functional diagram of a preferred system for planarizing the surface of polycrystalline or monocrystalline thin films produced during a sequential lateral solidification process in accordance with the present invention;

4a and 4b are schematic diagrams of a crystallized silicon film to be processed by the system of FIG. 3 using a narrow beam;

5 is a schematic diagram of a crystallized silicon film to be processed by the system of FIG. 3 using a broad beam;

6-7 are graphs showing the surface profiles of typical thin films before and after processing of the system of FIG. 3;

8 is a schematic diagram of a cross-section of a crystalline silicon film processed by the system of FIG. 1 according to a second embodiment of the present invention;

Figure 9 is a graph showing the surface distribution of a typical film that has been processed according to a second embodiment of the present invention;

FIG. 10 is a flowchart showing the steps performed in the system of FIG. 3 according to the first embodiment of the present invention; and

FIG. 11 is a flow chart showing steps performed in the system of FIG. 1 according to a second embodiment of the present invention.

Preferred Embodiments of the Invention

The present invention provides techniques for planarizing the surface of polycrystalline and single crystalline thin film semiconductors. In a preferred embodiment, the surface planarization technique is used as a post-processing step for polycrystalline and monocrystalline thin film semiconductors produced during a sequential lateral solidification process, or as a method for producing polycrystalline and monocrystalline thin films during a sequential lateral solidification process Processing steps during semiconductor. Accordingly, in order to fully understand these techniques, one must first understand the sequential lateral curing process.

The sequential lateral solidification process is a technique that produces large-grained silicon structures by making the silicon sample translate in small increments in one direction in the middle of sequential pulses emitted by an excimer laser. As each pulse is absorbed by the sample, a small region of the sample is completely melted and laterally resolidified into the crystalline region produced by the preceding pulse of a pulse set.

A particularly advantageous sequential lateral The curing process, as well as the equipment for performing the process, are incorporated herein by reference. Although the disclosure of the above techniques has been made with respect to the particular technique described in our co-pending patent application, it should be understood that other sequential lateral curing techniques can be readily applied to the present invention.

Referring to FIG. 1, our co-pending patent application describes as a preferred embodiment a system comprising an excimer laser 110, a fluence modulator 120 to rapidly vary the fluence of the laser beam 111, beam attenuation and a shutter 130 , optical elements 140, 141, 142 and 143, beam homogenizer 144, lens systems 145, 146 and 148, shielding system 150, lens systems 161, 162, 163, incident laser pulse 164, silicon thin film sample 170, sample translation stage 180 , granite block 190 , support systems 191 , 192 , 193 , 194 , 195 , 196 and management computer 100 . The translation of the silicon sample 170 in the X and Y directions can be achieved by moving the mask 710 in the masking system 150 or the movement of the sample translation stage 180 under the command of the computer 100 .

As described in our co-pending patent application, samples of amorphous silicon thin films are processed into single crystal or polycrystalline silicon thin films by: generating multiple excimer laser pulses with a predetermined fluence; Flux; average the adjusted laser pulse in a predetermined plane; shield the part of the averaged adjusted laser pulse to make it a patterned sub-beam; irradiate the amorphous silicon film with the patterned sub-beam the sample, having portions thereof melted corresponding to the beamlets; and controllably translating the sample relative to the patterned beamlets and with respect to the controllable adjustment, by sequentially translating the sample relative to the patterned beamlets, and by The sample is irradiated with patterned sub-beams with varying fluence at the corresponding sequential positions, and the amorphous silicon thin film sample is processed into a single crystal or polycrystalline silicon thin film.

While the sequential lateral solidification process is highly advantageous in producing single crystal or large-grain polysilicon thin films, the resulting crystals often exhibit rough surfaces due to the irrational nature of melting and solidification inherent in the crystal growth process. Thus, as shown in Figure 2, a 200nm thick crystal will exhibit height variations throughout the crystal length. In Figure 2, a height of 0 indicates the optimum height in a 200nm thick crystal, heights varying from 175nm to 225nm are shown to be common throughout the crystal length. Note that the large bump 210 is close to the boundary of the crystal where the crystal thickness is more than 350nm from the optimum thickness of 200nm.

Referring to Figures 3 and 4, a first embodiment of the present invention will now be described. Figure 3 shows a post-processing system for planarizing polycrystalline and single crystalline thin film semiconductors produced by a sequential lateral solidification process. The system includes an excimer laser 310, a beam attenuator and a shutter 320, a reflector 330, shrinkable lenses 331, 332, a reflector 333, a beam homogenizer 340, a condenser lens 345, a reflector 347, and a field (field) A lens 350 , a sample 360 , a sample translation stage 370 , an optical workbench 380 and a management computer 300 . A preferred laser 310, attenuator 320, pinch lenses 331, 332, homogenizer 340, and sample translation stage 370 capable of moving in orthogonal directions are all described in copending application Ser. No. 09/390,537. Workbench 380 may be as described in this patent document, or may be a common workbench. Preferably, for the homogenized beam 346 to form a top hat distribution in the x and y directions, the beam fluence must be lower than that required to completely melt the sample 360 .

Referring to Figures 4a and 4b, the sample 360 is shown in more detail. As the sample in this example has been processed, it already includes a large number of single crystal regions, which are shown schematically as mountain-shaped crystals 365 . A homogenized beam 346 is shown incident on a portion 361 of a sample 360 to locally melt it.

For a 200nm thick silicon film, the complete melting threshold is approximately 600mJ/cm2. Thus, to induce sufficiently localized melting of portion 361, beam 346 with an energy approximately 25% to 75% of the complete melting threshold should be utilized. If the energy of the beam is higher, the energy fluctuations inherent in excimer lasers will give rise to the possibility of complete melting of the sample region 361 . If the beam energy is low, sample portion 361 will not melt sufficiently to achieve satisfactory planarization.

As shown in FIG. 4 b , the sample 360 includes a silicon oxide base layer 400 and a silicon layer 410 . According to the invention, the outer surface of the silicon layer 410 is melted to a depth 420 . Upon re-solidification, rough surface 430 reforms in a more planar manner.

While a single homogenizing beam pulse of energy approximately 25% to 75% of the complete melting threshold is sufficient to cause localized melting of region 361, it is preferable to irradiate each such region with multiple beam pulses. Each subsequent beam pulse will cause localized melting of the region 361 whereby the re-solidification will exhibit a more planarized surface. Thus, using ten beam pulses per region 361 will produce a much smoother surface than using a single pulse.

Returning to FIG. 4 a , under the control of the computer 300 , the sample stage 370 is translated from right to left so that the homogenized beam 346 is scanned 450 from left to right on top of the sample 360 . Then, the platform 370 is moved in an orthogonal direction (shown as the Y direction) to reposition the sample in a new position 460, and translation 470 is initiated in the opposite direction. This process is repeated until the entire surface of the sample 360 has been scanned by the homogenizing beam 346 .

When translating the sample stage in the Y direction, it is advantageous to align the homogenizing beam to slightly overlap the area of the sample 360 that was previously scanned. Thus, if the area 361 is 1.2 x 1.2 cm, a Y-direction translation of 1.15 cm can be used to avoid edge effects caused by irregularities in the homogenized beam. Also, advantageously, there is a slight overlap with the translation in the X direction.

Although described above with respect to a square homogenized beam of top-hat distribution, other shaped beams may be utilized. Thus, as shown in FIG. 5, a homogenized beam 500 that is wide enough to eliminate the need for translation in the X direction can be utilized, with the advantage of requiring less movement of the translation stage 360 and thus greater throughput. Also, beams shaped with a Gaussian distribution along the X direction can be utilized if there is a large overlap between X translations.

As shown in Figures 6-7, the results of the process described with reference to Figures 3-4a are shown. The distribution of samples 360 fabricated according to the sequential lateral curing process is shown in Fig. 6a. The sample exhibited surface irregularities +/- 25nm from the optimum 200nm height. As shown in Figure 6b, these surface irregularities are significantly reduced after post-processing according to the invention with a single laser pulse. These results are also shown in FIG. 7 , which shows a reduction in surface roughness of more than 100% as a result of the post-processing according to the invention.

Referring again to Fig. 8, a second embodiment of the present invention will be described. In this embodiment, the planarization of the silicon thin film surface is maintained by utilizing a rigid capping layer during the sequential lateral curing process. Thus, FIG. 8 shows a thin silicon sample formed from an approximately 50-200 nm thick amorphous silicon layer 810 deposited on a silicon oxide base layer 820 . The sample was covered with a thick second silicon oxide layer 820 which was approximately 2 microns thick and was substantially rigid. The overlay must be thick enough to withstand the shrinkage and expansion during the melting and shaping cure of the silicon layer during the sequential lateral curing process.

Then, instead of sample 170, a sample with cover layer 830 was used in the lateral curing process, the full description of which is contained in the above-mentioned Ser. No. 09/390,537. After this processing, the capping layer 830 is removed from the sample by conventional wet or dry etching techniques. As shown in FIG. 9 , the result of the process described with reference to FIG. 8 is shown.

Referring to FIG. 10 , the steps performed by computer 300 to control the sequential lateral curing process of FIG. 1 and the surface planarization process performed with respect to FIG. 3 will be described. The electronics of the system are initialized 1000 by computer 300 to begin the process. Then, the sample is loaded onto the sample translation stage 1005 . It should be noted that this loading can be done manually or automatically under the control of computer 300 . Next, the sample is processed 1010 using the apparatus of FIG. 1 according to a sequential lateral curing process. The processed sample is positioned for planarization 1015. Optical elements of the system are brought into focus 1020 as necessary. The laser is then stabilized 1025 to the power level and reliability required to locally melt the sample according to the techniques of the present invention. Fine-tuning 1030 is made to the attenuation of the laser pulses, if desired.

Next, translation 1035 of the sample is started at a predetermined speed along a predetermined direction according to the sample region previously processed by sequential lateral curing. The shutter 1040 is opened to expose the sample to radiation and start the planarization process accordingly.

Sample translation and irradiation is continued until planarization has been completed 1045, 105, at which point the computer closes the shutter and stops translation 1055, 1060. If other areas on the sample are specified to be planarized, the sample is repositioned 1065, 1066 and the process is repeated on this new area. If it is specified that no areas need to be planarized, then the laser is turned off 1070, the hardware is turned off 1075, and the process ends 1080.

Referring next to FIG. 11 , the steps performed by the computer 100 to control the crystal growth process with respect to the surface planarization step performed with respect to FIG. 1 will be described. FIG. 10 is a diagram illustrating the basic steps performed in the system of FIG. 1 using the covered sample shown in FIG. 8 . An oxide layer is deposited on the substrate 1100 . Then, a silicon layer is deposited on the oxide buffer layer 1110 and a capping oxide is deposited on top of the sample 1120 .

Next, the samples were processed according to the sequential lateral curing process using the equipment of Figure 1. After processing, the covering oxide is removed, for example, by dilute hydrofluoric acid solution.

The foregoing merely illustrates the principles of the invention. Various modifications and alterations to the described embodiments will become apparent to those skilled in the art from the disclosure herein. For example, although a dilute hydrofluoric acid solution has been disclosed for removal of the overburden, the overburden may be removed by any conventional technique, such as dry etching. It will thus be appreciated that those skilled in the art can devise various systems and methods which, although not explicitly shown or described herein, embody the principles of the invention while remaining within the spirit and scope of the invention.

Claims (21)

1. system that is used to reduce the surface roughness of polycrystalline by the sequential lateral solidifcation explained hereafter or monocrystal thin films comprises:

(a) excimer laser is used to produce a plurality of quasi-molecule laser pulses with predetermined fluence;

(b) optical coupled is to the energy density adjuster of described excimer laser, be used for controllably regulating the fluence of the described quasi-molecule laser pulse of described excimer laser emission, thereby described fluence is lower than and makes described polycrystalline or monocrystal thin films melt required fluence fully;

(c) be coupled to the beam homogenizer of described energy density adjuster optically, be used for described laser pulse homogenizing in a predetermined plane through regulating;

(d) sample stage is used to receive the laser pulse of described homogenizing, so that the part of described polycrystalline or monocrystal thin films is corresponding to the laser pulse of described homogenizing and local the thawing;

(e) be coupled to the translating device of described sample stage, be used for the relative position of the described sample stage of controllably translation with respect to the laser pulse of described homogenizing; And

(f) be coupled to described excimer laser, the computer of described energy density adjuster and described translating device, be used to control the controlled fluence adjusting of described quasi-molecule laser pulse and the described controlled relative position of described sample stage and described homogenizing laser pulse, and the generation of described quasi-molecule pulse and the adjusting of described fluence are coordinated with the described relative position of described sample stage and described homogenizing laser pulse, thereby pass through with respect to the described sample stage of described homogenizing laser pulse order translation, the respective sequence position on described polycrystalline or monocrystal thin films processes it.

2. the system as claimed in claim 1 is characterized in that described excimer laser is the ultraviolet excimer laser that is used to produce ultraviolet quasi-molecule laser pulse.

3. the system as claimed in claim 1 is characterized in that described beam homogenizer can be used to make described laser pulse to form along the top cap of x and y direction and distributes.

4. the system as claimed in claim 1 is characterized in that described energy density adjuster can be used to make that the described fluence of described quasi-molecule laser pulse decays to described polycrystalline or monocrystal thin films melts 25% to 75% of threshold value fully.

5. the system as claimed in claim 1, it is characterized in that described sample stage comprises Y direction translating sections, described Y direction translating sections, allow to move along direction with described homogenizing laser pulse quadrature, and can be by described computer control, with along described orthogonal direction controllably described polycrystalline of translation or monocrystal thin films.

6. system as claimed in claim 5, it is characterized in that described beam homogenizer can be used to make described modulated laser pulse to form at least along the top cap with the described direction of the direction quadrature of described modulated laser pulse and distributes, described translating device can be used to along with the described polycrystalline of described direction translation or the monocrystal thin films of the direction quadrature of described modulated laser pulse, thereby the laser pulse of order homogenizing incides on the overlapping region slightly of described polycrystalline or monocrystal thin films.

7. the system as claimed in claim 1, it is characterized in that described sample stage comprises directions X translating sections and Y direction translating sections, each part all is coupled to described computer and intercouples, described X and Y direction translating sections allow to move along two orthogonal directions with respect to described homogenizing laser pulse, each part can be by described computer control, with along described two orthogonal directions described sample of translation controllably.

8. system as claimed in claim 7, it is characterized in that described beam homogenizer can be used to make described modulated laser pulse to form along the top cap of x and y direction and distributes, described translating device can be used to along with the described polycrystalline of both direction translation or the monocrystal thin films of the direction quadrature of described homogenizing laser pulse, thereby the laser pulse of order homogenizing incides on the overlapping region slightly of described polycrystalline or monocrystal thin films along described both direction.

9. method that is used to reduce the surface roughness of polycrystalline by the sequential lateral solidifcation explained hereafter or monocrystal thin films may further comprise the steps:

(a) produce a plurality of quasi-molecule laser pulses with predetermined fluence;

(b) controllably regulate the fluence of the described quasi-molecule laser pulse of described excimer laser emission, thereby described fluence is lower than and makes described polycrystalline or monocrystal thin films melt required fluence fully;

(c) described laser pulse homogenizing in a predetermined plane through regulating;

(d) part that makes described polycrystalline or monocrystal thin films is corresponding to the laser pulse of described homogenizing and local the thawing;

(e) controllably described polycrystalline of translation or monocrystal thin films with respect to the relative position of described homogenizing laser pulse, with by with respect to the described sample stage of described homogenizing laser pulse order translation, the respective sequence position on described polycrystalline or monocrystal thin films processes it.

10. method as claimed in claim 9 is characterized in that described quasi-molecule laser pulse comprises ultraviolet quasi-molecule laser pulse.

11. method as claimed in claim 9 is characterized in that described homogenization step comprises that described modulated laser pulse is all changed into the top cap that has along x and y direction to distribute.

12. method as claimed in claim 9, what it is characterized in that described regulating step comprises that the described fluence that makes described quasi-molecule laser pulse decays to described polycrystalline or monocrystal thin films melts 25% to 75% of threshold value fully.

13. method as claimed in claim 9, it is characterized in that described translation step comprise along with a direction of the direction quadrature of described homogenizing laser pulse controllably described polycrystalline of translation or monocrystal thin films.

14. method as claimed in claim 13, it is characterized in that described homogenization step comprises that described modulated laser pulse is all changed into the top cap that has at least along with the described direction of the direction quadrature of described modulated laser pulse to distribute, described translation step comprise along with the described polycrystalline of described direction translation or the monocrystal thin films of the direction quadrature of described homogenizing laser pulse, thereby the laser pulse of order homogenizing incides on the overlapping region slightly of described polycrystalline or monocrystal thin films.

15. method as claimed in claim 9 is characterized in that described translation step comprises edge two orthogonal directions vertical with described homogenizing path that laser pulse forms controllably described polycrystalline of translation or monocrystal thin films.

16. method as claimed in claim 15, it is characterized in that described homogenization step comprises that the top cap that described modulated laser pulse is all changed on the described both direction that has with the direction quadrature of described modulated laser pulse distributes, described translation step comprise along with the described polycrystalline of both direction translation or the monocrystal thin films of the direction quadrature of described homogenizing laser pulse, thereby incide on the overlapping region slightly of described polycrystalline or monocrystal thin films along described both direction through the laser pulse of order homogenizing.

17. method as claimed in claim 9, it is characterized in that the described part of described translation step described polycrystalline that has been included at least two homogenizing laser pulse irradiation or monocrystal thin films after, described polycrystalline of translation or monocrystal thin films.

18. one kind is used for the amorphous silicon membrane sample is processed into the monocrystalline that surface roughness reduces or the method for polysilicon membrane, may further comprise the steps:

(a) be enough to bear that described silicon thin film is melting and form the rigidity cover layer on the amorphous silicon membrane sample of the pucker ﹠ bloat of setting up period again at thickness;

(b) produce an excimer laser pulse train;

(c) each quasi-molecule laser pulse in the described sequence controllably is adjusted to predetermined fluence;

(d) each laser pulse homogenizing in a predetermined plane in the described sequence through regulating;

(e) cover the part of the controlled homogenizing laser pulse of each fluence in the described sequence, have the controlled pulse train of fluence of patterned beamlet to produce one;

(f),, the part of described amorphous silicon membrane sample is melted with corresponding to the controlled patterned beamlet pulse of each fluence in the described pulse train of patterned beamlet with the controlled patterned beamlet sequence irradiation amorphous silicon membrane sample of described fluence;

(g) with respect to through the controlled pulse of each described fluence of patterned beamlet, the described sample of order translation controllably, thus described amorphous silicon membrane sample is processed into monocrystalline or polysilicon membrane; And

(h) remove described cover layer from described monocrystalline or polysilicon membrane.

19. method as claimed in claim 18 is characterized in that described quasi-molecule laser pulse comprises ultraviolet quasi-molecule laser pulse.

20. method as claimed in claim 18 is characterized in that being included on the described amorphous silicon membrane sample and forming silicon oxide layer forming the tectal described step of rigidity on the described amorphous silicon membrane sample.

21. method as claimed in claim 18 is characterized in that forming the silicon oxide layer that the tectal described step of rigidity is included in formation 2 micron thickness on the described amorphous silicon membrane sample on the described amorphous silicon membrane sample.

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