TWI331228B - Laser beam delivery system and method thereof, and laser lift-off method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a laser beam delivery system and method thereof, and more particularly to a laser beam delivery system for separating a thin touch from a substrate and • The method, and more particularly, a laser beam delivery system and method thereof can be applied to laser lift-off technology (LLO, Laser Lift-Off), which is a k-type vertical light-emitting diode (LED) Indispensable steps • [Prior Art] In general, excimer laser devices have a variety of applications in processing materials, for example, to precisely process and separate two different materials that are combined with each other. Recently, since the stability and load of the excimer laser beam have been improved, the range of use has been gradually expanded to include processing semiconductor materials, and, in particular, including separating a film from a wafer to fabricate a device. There are many different types of films that are separated, including composite semiconductors, copper, ingots, gold, and polymers. In order to separate the different thin films, the laser beam has substantial elements such as target energy density, target energy uniformity, and target exposure range. The following will explain the conventional art and the present invention according to the laser stripping technique, which is a necessary step for manufacturing a vertical type light-emitting diode. However, the field of the invention is not limited to laser stripping. The second system is a semiconductor device that converts current into light. When the electrons of the active layer fall back to the valence band, the electrons of the sustaining layer are activated by the valence band of the semiconductor across the corresponding 'gap' TW3624PA/ OP06-QM-002-TW-00 5 I3·312?8. The wavelength and color of the light depend on the bandgap energy, and because the bandgap energy is one of the properties associated with the material, the wavelength and color of the light are also affected by the semiconductor material. - Light-emitting diodes emit different ranges of colored light, such as red light, green light, and light and yellow light. However, the light-emitting diode has a limitation of a monochromatic light source. In some cases, the light-emitting diode must emit white light containing three types of light: red, green, and blue. For example, a backlight unit of a liquid crystal display must emit white light. Usually, white light is provided by an incandescent light bulb or a fluorescent light. Although incandescent bulbs are relatively inexpensive, they have a short life span and low luminous efficiency. However, the limited service life is a disadvantage of the township light, but it is more efficient than the incandescent light bulb. In addition, fluorescent lamps require an additional relatively large, heavy, and expensive part, such as a voltage regulator. One of the white light-emitting diodes is fabricated by bringing the light-emitting diodes such as red, green, and blue light into close proximity to each other, and by causing each of the light-emitting diodes to emit an appropriate proportion of light. However, it is not easy to manufacture a blue light-emitting diode because of the difficulty in manufacturing a proper crystal with a corresponding band gap. In particular, it is difficult to polymerize a good-quality blue light-emitting diode with a composite semiconductor such as Inp, GaAs, and Gap. In addition to the above difficulties, a blue light-emitting diode based on gallium nitride (GaN) has been commercially used since it was introduced to the market in 1994. Gallium nitride (GaN) blue light-emitting diode technology is rapidly evolving, making it a leader in the field of white light bulbs and fluorescent bulbs. Meanwhile, if a light-emitting diode based on InP, GaAs or Gap is used, since these types of semiconductor layers can be grown on a conductive substrate, it is difficult to manufacture TW3624PA/QP06-QM-002-TW-00 6 i3?1228 with A vertical type light emitting diode in which the positive and negative electrodes are joined. However, if a gallium nitride (GaN)-based light-emitting diode, a non-conductive sapphire (Alz〇3) substrate is used to reduce crystal defects, this defect can occur during the growth of the gallium nitride film, and because sapphire As a non-conductive substance, a horizontal type light-emitting diode having first and second electrodes on the top surface of the upper layer has been gradually adopted. 1A and 1B show a schematic view of a vertical type light emitting diode structure of the prior art. Fig. 1A shows a cross-sectional view of one of the vertical type light-emitting diodes of the prior art. Referring to Fig. 1A, an n-type nitrided layer of Ganu, a plurality of quantum well-activated layers 12, a germanium-type gallium nitride layer 13 and a transparent conductive layer 14 are successively formed on a sapphire substrate. Then, a first electrode 15 is formed on a specific portion of the transparent conductive layer 14. Further, a photoresist pattern (not shown) is formed on the transparent conductive layer 14 including the first electrode 15, and therefore, part of other parts of the transparent conductive layer 14 which is not formed of the first electrode 15 is not covered. Photoresist pattern. The transparent conductive layer 14, the P-type gallium nitride layer 13, and the active layer 12 are selectively etched using a photoresist pattern as a mask. At this time, a portion of the n-type gallium nitride layer 11 is slightly etched. Wet etching is preferred over dry etching because the gallium nitride layer is not easily etched. Therefore, the photoresist pattern is removed through a removal process, and a second electrode 16 is formed on the exposed portion of the layer 11 n. As shown in FIG. 1B, the figure (3) is a conventional technique. The top view of the LED is that the electrode tube 15 and the second electrode tube 16 need to be combined with the wire TW3624PA/OP06-QM-002-TW-00 7 1331228 • f. Therefore, the chip of the LED should be large enough to protect. In this electrode region, the wafer acts as an obstacle to the increase in output per unit of wafer. In addition, the complicated wire bonding in the packaging process increases the production cost. • Furthermore, since the sapphire substrate is not conductive, it is very It is difficult to generate static electricity to increase the possibility of producing poor devices and to reduce the effectiveness of the device. In addition, because sapphire has low thermal conductivity, sapphire does not easily emit heat radiation for high output power LEDs when LEDs are used. The characteristics limit the high current of the light-emitting diode. • To solve the limitations and disadvantages of the horizontal light-emitting diode, the vertical light-emitting diode, especially without the sapphire substrate Straight light emitting diodes have been extensively studied. - If the vertical type light emitting diode does not have a sapphire substrate, a gallium nitride epitaxial layer is formed on a sapphire substrate, and a metal supporting layer is formed on the epitaxial layer. Since the sapphire layer is removed from the §Haixian layer, the telecrystal layer may be supported by the metal support layer, so it is feasible to separate the sapphire layer from the surface layer. In general, a laser lift-off (LLO) technique is used. Separating the sapphire® layer from the worm layer. The basic theory of laser stripping technology is that a material with a band gap is permeable to light below the band gap energy, but absorbs light above the band gap energy. For example, a KrF 氪fluoroexcimer laser beam with a wavelength of 248 nm, and a fluorine-based JrF excimer laser beam with a wavelength of 193 nm, a band gap of about 3.3 eV for gallium nitride and a band of about 10. OeV for sapphire. The energy between the two, the excimer laser beam penetrates the sapphire substrate and is absorbed into the gallium nitride epitaxial layer. Therefore, the excimer laser TW3624PA/ OP06-QM-002- penetrates the sapphire substrate. TW-00 8 beam is heated and The epitaxial layer of the interface is separated by the + crystal layer. The sapphire substrate is generally divided into two groups based on how the illuminating technique has multiple luminescent stripping techniques, and the wafer of the 5 device is scanned. When using the scanning method, there are some methods and pulse methods. The part that is repeatedly irradiated may be broken or may be avoided repeatedly to avoid this problem, preferably by the phenomenon of pulse I疋 rupture. The beam pulse is applied to a unit illumination P method, that is, the area to be irradiated is applied, and a laser beam is applied to the field; the field is moved to the next picture, and then the steps are repeated until the area of the wafer is irradiated Although the pulse method is employed, the target area is illuminated. The shape and size correspond exactly to the unit illumination area f-beam point, and the part of the beam is irradiated to the single part ===break or crack. On the other hand, if the pure domain is used, the gemstone substrate can not be separated from the nitrided crystal layer. Even if the size and shape of the beam spot completely correspond to the unit illumination area, the above problem still occurs if the energy intensity does not uniformly distribute the entire area of the beam spot. That is, as shown in Fig. 2, since the energy intensity of the original laser beam section is Gauss's law, the original laser beam has a higher energy intensity at the center portion and a lower energy in the surrounding portion. Therefore, if the energy intensity of the laser beam is sufficiently large to ensure that the sapphire substrate is separated by the gallium nitride epitaxial layer of the peripheral portion of the unit irradiation region, defects may occur in the central portion of the unit irradiation region. Another TW3624PA/ OP06-QM-002-TW-00 9 1331228 ^ * Aspect 'If the energy intensity of the laser beam is low to prevent defects in the center of the unit illumination area, the sapphire substrate cannot be illuminated by the unit. The gallium nitride epitaxial layer is separated. In summary, the use of an original laser beam that does not have any adverse effect on throughput, compared to the number of all light-emitting diode devices, yields the number of light-emitting diode devices that may be manufactured from a single wafer. Therefore, as shown in Figs. 3A to 3C, a beam homogenizer φ ι 〇 0 is used to increase the uniformity of the energy intensity of the beam spot. The beam homogenizer 100 of the prior art includes a first compound eye microlens 11 〇 and a second compound eye microlens 12 〇, and a concentrating lens 13 重叠 for overlapping a plurality of ion beams, the first and second compound eye microlenses The laser beam is used to separate the laser beam from a laser beam source into a plurality of small ion beams (not shown) and to adjust the dispersion angle of the small ion beam. However, the first compound eye microlens 11 〇 and the first compound eye microlens 12 习 of the prior art are cylindrical. The cylindrical compound-eye microlens 11 () is composed of two mutually combined plates 111 and 112, wherein each plate ill φ I12 is composed of a plurality of cylindrical lenses arranged in parallel with each other, and wherein the plate 111 The cylindrical lens is perpendicular to the other plate 112, thus forming a plurality of lenslets. For the cylindrical compound-eye microlenses 11 〇 and 12 〇, the distance of the lenslets as a compound-eye microlens is about 5 mm, and because of the structure of the fly-eye lens, the lenslets are not easily reduced in the length of the cymbal. Therefore, as shown in Fig. 3D, increasing the number of effective lenslets is limited by the fact that the effective lenslets actually penetrate the laser beam, and therefore it is also limited to increase the small beam dispersed by the laser beam. Therefore, because the cylindrical compound eye microlens small beam TW3624PA/ OP06-QM-002-TW-00 10 1331228

I. The limit of the increase of the target is that it is difficult to obtain the energy intensity of the beam point of the good hook, and therefore, compared with all the light-emitting diodes that may be fabricated by one wafer: the number of 'is the yield, good quality The number of light-emitting diodes will have an adverse effect on the party. , in addition to ¥, in order to increase the number of effective lenslets, by the beam diffusing telescope (βΕΤ) between the laser beam source and the beam homogenizer 100 (not in the figure, not in the figure), the cross section of the laser beam The size may be enlarged and a cylindrical compound eye microlens of sufficient size to receive the expanded laser beam is used. However, due to the limitation of system size, the energy intensity is still limited. In addition, because of the necessity to use a beam-diffusing telescope at the same time, the complexity of manufacturing the entire laser beam delivery system is increased, and the production cost is also increased. In addition, the beam transmission of the system is reduced because the laser beam must penetrate an additional optical component, which is the beam diverging telescope. Furthermore, in terms of beam transmission, the cylindrical compound-eye microlens η〇 and 120 have a major problem 'because the laser beam cannot penetrate the cylindrical compound-eye microlens between the cylindrical lens type interface, and a cylinder The type compound eye microlens comprises two layers, which are optical elements that allow the laser beam to penetrate. As a result, the light beam representing the size of the original beam passing through the entire system and being transferred to the wafer is small. Therefore, the output of the light-emitting diode per unit time is significantly limited. SUMMARY OF THE INVENTION A laser beam delivery system and method thereof, and a laser stripping method are used to substantially eliminate the limitations or disadvantages of the prior art. TW3624PA/OP06-QM-002-TW-00 11 1331228 One or more problems The man point system provides a certain method of light, the method of the knee, and the method of the laser beam transmission system, so that all the beam points are connected to the At曰~ field and the method of the method. The energy intensity of the point i is also significantly increased. ΊΊ 増 増 ,, and thus add another aspect of the invention - the advantage is that

The beam is woven, and this is improved. Each of the 彳 · · 方 方 七 - - - - - - - - - - - - - - - - - 优点The method, and the laser method, the laser stripping method, the production system is simplified, the production cost is reduced, and thus the competitiveness of the light-emitting body market is improved. Other advantages and features of the present invention will be set forth in the following examples, which may be more apparent from the examples. And the structure and drawings shown in the patent specification, and the advantages thereof, can be achieved and achieved. π ° In order to achieve the above advantages and to meet the objectives of the present invention, a beam delivery system is proposed. The laser beam delivery system comprises: a laser beam - a source, a beam homogenizer, a reticle, and an image lens, wherein the beam source is used to emit a laser beam - the beam homogenizer - a microlens type compound eye a lens for accommodating the uniformity of the energy intensity of the laser beam, the reticle covering the area around one of the sections of the laser beam, and penetrating the beam homogenizer at a focal plane, and the image lens is used to make the beam The beam of light is illuminated in a unit radiation area of a target. TW3624PA/ OP06-QM-002-TW-00 12 1331228 Another aspect of the invention provides a method of transmitting a laser beam, the method comprising: emitting a quasi-molecular laser beam, using a microlens type fly-eye lens, to emit The excimer laser beam is divided into a plurality of small beams, and the plurality of small beams are partially overlapped, thereby producing a homogeneous laser beam, covering a surrounding area of the homogenized laser beam, and homogenizing the cover The laser beam acts on the target.

Another aspect of the present invention provides a laser stripping method comprising: forming a gallium nitride epitaxial layer on a sapphire substrate, emitting a pseudo-molecular laser beam, and using a microlens type fly-eye lens The emission is 7 molecules, the beam is divided into a plurality of small beams, and the plurality of small beams are partially overlapped. Thus, a homogeneous laser beam is produced, and a homogenized lightning beam is covered: the surrounding area of the beam, and the covered area is homogenized. The laser beam acts on the sapphire == laser area 'and the vermiculite substrate from the coffee

TW3624PA/ OP06-QM-002-TW-00 1331228

[Embodiment] The reference material will be described in detail in an embodiment of the present invention, and an example thereof will be described in the following drawings. It will be appreciated that in addition to the following description and illustration, a laser beam delivery system further includes any optical component, such as a mirror, which is also within the scope of the invention. 4A to 4G are cross-sectional views showing an assembly method of a vertical type light emitting diode according to the present invention. Referring to FIG. 4A, a plurality of successive layers 30 include a gallium nitride buffer layer 31, an N-type gallium nitride layer 32, an InGaN/GaN/AlGalnN active layer 33 having a multi-quantum well, and a P-type nitrogen. The gallium layer 34 is successively formed on a sapphire substrate 20 by a conventional semiconductor technology, such as metal oxide chemical vapor deposition (M〇CVD, Metal 〇xide).

Chemical Vapor Deposition) and molecular beam epitaxy (MBE,

Molecular Beam Epitaxy). If a gallium nitride film directly forms φ on a sapphire (A1203) (001) substrate, the lattice inconsistency may be detrimental to the surface uniformity of the film. Therefore, it is more desirable to first form a buffer layer 31 and then form a gallium nitride based layer on the buffer layer 31. Typically, the sapphire substrate 20 has a thickness of about 330 // m to 40 // m. The thickness of the entire continuous gallium nitride based layer 30 is less than about 5/zm. As shown in Fig. 4B, a plurality of trenches 40 are formed on the continuous nitrided graft layer 30a and through the nitride substrate 30a. These trenches may extend to the sapphire substrate 20a at a predetermined depth to avoid any defects. In addition, these defects may occur in the sapphire substrate 2A by gasification recorded TW3624PA/OP06-QM-002-TW-00 14 1331228 The base layer 30a is separated from the subsequent steps. The trench 4 is used to define individual light emitting diode devices and to assist in a subsequent wafer separation step. Each of the other light-emitting diode semiconductors is advantageously a square of - large f. The trench 40 is advantageously narrower and extends deeper than 5#m to the sapphire substrate 2〇a. Because of the hardness of the sapphire substrate 20 and the gallium nitride base layer 3, the formation of the trench 4 is more advantageous by using a reactive ion etching system.

It should be lightly combined with the electric reaction type ion #1 (? RIE). Since the first step is to form the trench 40, a photoresist (not shown) is spin-coated on the gallium nitride based layer 30 and then patterned by use and development techniques. After development, an inductively coupled plasma reactive ion etch (IcpRi process 'shows as a photoresist as a mask, and selectively #base 30 and sapphire substrate 20, thus forming the trench 4〇. #照第4C @ '(4) After the formation of the canal 40 is formed on the entire upper surface of the nitrogen 3〇a and the sapphire substrate 20a, forming a conductive base layer

50. Therefore, the trench 40 is filled with a conductive support layer 5〇. Although 4 = layer 5 〇 can be composed of any non-metallic substance, for example, it has excellent (four) conductivity. However, it is well-formed by the Lai vapor deposition method vapor deposition method or fit, such as copper gold and aluminum. nΜ may be formed in a step to strengthen a layer between the two (not shown), including Cr or gold, adhesion between the gallium nitride base layer 30a and the conductive support layer 5〇. Referring to FIG. 4D, according to this Invented laser beam delivery system

TW3624PA/ OP06-QM-002-TW-00 丄 228, = after holding the 5G domain, 'When the vacuum pad makes the sapphire substrate 2Qa deviate from the gallium base layer 30a, the laser beam is irradiated onto the sapphire substrate, so that The sapphire substrate 20a is separated from the .A u 匕 gallium base layer 30a by a tantalum nitride. This process will be described in detail below. As in Fig. 4E, the lower surface ' of the gallium nitride based layer 30a with respect to the conductive support layer 5 is cleaned by vaporized hydrogen and then polished to smooth the surface. Referring to Fig. 4F, a plurality of contact layers 60 are formed on the unmasked surface of the gallium nitride based layer 3?a. Each of the contact layers 6A includes an interfacial layer μ and a contact pad 62, the interfacial layer 61 directly contacts the gallium nitride based layer 3A, and the contact pad 62 is positioned over the interfacial layer 61. It is more desirable that the interface layer 61 contains a titanium element or an aluminum element, and the contact pad contains Cr and Au-based elements. After the plurality of contact layers 60 are formed, the steps of dividing into small squares are performed to separate the structures in Fig. 4 into individual light emitting diode devices. This _ dicing step can be performed by different mechanisms or using different chemical methods. Figure 4 shows the final product of a light emitting diode device. In the above steps, the process of separating the sapphire substrate 20a from the gallium nitride base layer 30a can be efficiently achieved by the laser beam delivery system of the present invention. For a detailed description of this step, refer to FIG. 5 to 8 picture. Figure 5 is a schematic illustration of a laser beam delivery system in accordance with the present invention. Referring to Fig. 5, the laser beam delivery system of the present invention comprises a Ray TW3624PA/〇P〇6-QM.〇〇2-TW-00 16 1331228 beam source 210. Because the KrF excimer laser beam with a wavelength of 248 nm and the ArF excimer laser beam with a wavelength of 193 nm have an energy, it is between the 3·3eV band gap of GaN and the sapphire. 〇eV band The molecular beam (4) beam penetrates the sapphire substrate 2Qa but is absorbed in the gas=gallium base layer 30a. Thus, both laser beams can be considered as the laser beam source 210 of the present invention. However, the KrF excimer laser beam is better than the two-F quasi-sub-field laser beam because the ArF quasi-split beam may be less absorbed in the sapphire substrate 20a. * The laser beam source 210 emits a laser beam in a pulse wave manner. The pulse wave energy of the laser beam can be adjusted by a different attenuator (the picture is not: the field is precisely adjusted. 'Substantially, because the energy intensity of the cross section of the laser beam emitted by the laser beam source 210 is Gaussian. Therefore, it is necessary to increase the energy of the beam point to produce three sentences. In this case, the laser beam is cut by the direction of the vertical direction of the beam. 〇°Using a light east homogenizer to boost energy=:2=The energy intensity curve of the entire section of the laser beam is (4) where the laser beam is at the focus 220. The detailed structure and its functional description are as pi as beam homogenizer As shown in Fig. 5, in order to adjust the distance between the planes of the beam homogenizer 2, the focus plane has been worn by "one ten ten," then the local beam emission system _ can include the first beam homogenizer (10) Between the focal plane and the focal plane - the laser beam delivery system of the present invention includes a focus; TW3624PA / OP06-QM-002-TW-00 γη 1331228 reticle 240, the position of the focal plane by the image field The lens mo is adjusted, so the light is transmitted Homogenization; the circumference of the beam* beam is shielded from the focal plane. Therefore, the entire section of the shielded laser beam has a complete and uniform energy intensity. The shielded laser beam is transmitted through an imaging lens 25 Going to a unit irradiation area of one wafer 300. Once the entire surface of the wafer 3 is sequentially irradiated, the sapphire substrate 20a is separated by the gallium nitride base layer 3A. 6A to 6C are in accordance with the present invention. A beam homogenizer 22 permeable view 'a top view and a side view. According to an embodiment of the invention, the beam homogenizer 22 includes a microlens type one of the first fly-eye lens 221 and a second fly-eye lens 222 and a concentrating lens 223, wherein the first fly-eye lens 221 splits the laser beam 21 〇 emitted by the laser beam into a plurality of small beams, and the second fly-eye lens 222 is used to spread the plurality of small beams in 5 weeks. The concentrating lens 223 is used to adjust the plurality of small beam dispersion angles of the knives, so that the intercepting surface of the laser beam has a uniform energy intensity curve at the focal plane. That is, the beam of the present invention. Homogenizer 2 2 〇 is a microlens type fly-eye lens 221 and 222. A microlens type fly-eye lens refers to a single stone lens having a plurality of small lenses, and is formed into a lens plate by using a semiconductor etching step. The lens of the mode is used to manufacture the microlens type fly-eye lens. Therefore, there is no interface between the lenslets of the microlens type fly-eye lenses 221 and 222, and the beam of the cylindrical type fly-eye lens 11〇 and 12〇 is compared with the prior art. The penetration rate 'because the loss of the laser beam occurs at the interface, so there is more than TW3624PA/ OP06-QM-002-TW-00 18 1331228 « 1 high beam penetration rate. Purely knowing the skill, because the recording is less, The optical element 'is therefore the transmissive beam of the present invention, and the uniform beam reduction rate is further improved.

According to the present invention, 'because the microlens type fly-eye lenses 221 and 222 are manufactured by the semiconductor fairy step (four), the pitch can be reduced to several hundred (four) by the pitch (piteh). Therefore, as shown in Fig. 6D 'The fly-eye lens 221# 222 of the present invention has a smaller lenslet that the laser beam actually passes through than the cylindrical fly-eye lenses 110 and 120 of the prior art, and thus can divide the laser beam into more Small beam of light. Therefore, as shown in Figs. 7 and 8, the beam homogenizer 220 of the present invention can greatly improve the uniformity of the energy intensity of the laser beam section, which is far superior to the conventional beam homogenizer. . Although the reduction of the pitch of the fly-eye lenses 221 and 222 of the present invention can improve the uniformity of the energy intensity of the laser beam, if the pitch of the lenslet is too small, the small Wei H becomes too short to be read. The size of the beam, where the complex light on the flank plane follows the f: reference, the graph 'detailedly, the following formula should be = 足夕彰: the small beam of the shovel heavy tile, and the focal plane can be somewhat large fLAi<; a < fLA1 + fLA2 隹: Chinese and Japanese LA1 Lianghe-U are the distance between the first and second fly-eye lenses 221 and 222, respectively, and the distance between the second and second fly-eye lenses 221 and 222. TW3624PA/ OP06-QM-002-TW-00 19 1331228 ———[(/L41+Da] The size of the cross section is proportional to (where f*FL is the focal length of the condenser 223.) because the lens 221 '222 and Each focal length of 223 is constant, so the cross-sectional size of the focal plane of the laser beam is determined by a, that is, the distance between the first fly-eye lens 221 and the second fly-eye lens 222. If the focal length of the lenslet is too short Since a must conform to the above formula, the adjustable range of a is limited, and therefore the beam cross-section size can only be adjusted within a certain limit. Therefore, the size of the focal plane laser beam and the uniformity of energy intensity are considered. The pitch of the first fly-eye lens 221 and the second fly-eye lens 222 must be optimized. According to a preferred embodiment of the present invention, both the first fly-eye lens and the second fly-eye lens have a range of 到. 5 to 2 〇ηπι The pitch is as long as the above-mentioned 'cylinder type fly-eye lens 11' is required to be far away from the microlens type fly-eye lens 221' to divide the laser beam into the same number of small beams as the micro-type compound eye lens 221. Furthermore, each of the lenslets of the cylindrical lens 110 must be provided with an additional optical element, and 51 is a beam telescope added between the laser source and the cylindrical fly-eye lens 11〇. Since the beam homogenizer 22 of the present invention does not require such an extended telescope, the steps of manufacturing the system can be reduced, the cost of the system can be reduced, and the competitiveness in the market of the light-emitting diodes can be increased. In addition, the system of the invention of the invention uses fewer optical components than the prior art, so that the lightning can pass, so the overall beam penetration rate is improved, and the amount of 1331228 is 2 TW3624PA/ OP06-QM-002-TW-00 It also increased. In accordance with an embodiment of the present invention, the original KrF excimer laser beam section is a rectangle having a length of 10 nm and a width of 23 nm. Since each of the small lenses of the first fly-eye lens 221 has a pitch of 〇15 nm, the laser beam is split into about 230 small beams through the first fly-eye lens 221. According to an embodiment of the present invention, the first and second fly-eye lenses 221 and 222 are each a rectangle having a length of 15 nm and a width of 30 nm. In another aspect, in accordance with another embodiment of the present invention, each of the fly-eye lenses has a rectangular shape having a horizontal length of spring and a vertical length, and a ratio of a horizontal length to a vertical length of each of the fly-eye lenses is emitted from the laser source. The ratio of the horizontal length to the vertical length of the laser beam section is the same. Meanwhile, as shown in Fig. 5, although the distance sheet between the condensing mirror 223 and the focal plane is adjusted by the field lens 230, the field lens 230 is omitted in Fig. 6C for convenience of explanation. The focal plane 'through the laser beam passing through the beam homogenizer 220 of the present invention has an approximately square cross section, and the energy intensity of the entire section has a substantially improved uniformity. However, compared with other regions, the area around the wearing surface has Lower energy intensity. Thus, a reticle 240 is placed in the focal plane to shield the surrounding area such that only about eighty percent of the laser beam may be an effective beam. The shaded laser beam is directed through an imaging lens 250 to a unit illumination area of a wafer 300. Once the entire surface of the wafer 300 is sequentially irradiated, the sapphire substrate 2〇a is separated by the gallium nitride base layer 30a. Laser stripping technology is indispensable for the manufacture of a vertical LED. TW3624PA/ OP06-QM-002-TW-00 21 1331228

The technology of II, although the laser stripping technology has been used to illustrate the prior art and the present invention, the laser beam delivery system and method of the present invention are not limited to laser stripping technology, but can be applied to other semiconductor manufacturing. The step, in particular, is to separate a film on a wafer to make a device. In accordance with the present invention, various films, such as a composite semiconductor, copper, aluminum, gold, polymers, and the like, can be separated. As described above, according to the present invention, the uniformity of the energy intensity of the entire beam spot is increased, and thus the processing yield is also remarkably increased. In addition, the beam penetration rate increases and the yield per unit time increases. In addition, production steps are simplified, production costs are reduced, and their competitiveness in the market for light-emitting diodes is increased. In view of the above, the present invention has been disclosed in a preferred embodiment, and is not intended to limit the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims. TW3624PA/ OP06-QM-002-TW-00 22 1331228 [Simple Description of the Drawing] Fig. 1A is a cross-sectional view showing a horizontal type of light-emitting diode of the prior art. Fig. 1B is a top plan view showing a horizontal type of light-emitting diode of the prior art. Figure 2 is a graph showing the energy intensity of a section of an original laser beam. Figures 3A through 3C are respectively a perspective view, a top view and a side view of a beam homogenizer of the prior art. Fig. 3D is a diagram showing an effective lenslet of a cylindrical fly-eye lens used in a beam homogenizer of the prior art. 4A to 4G are cross-sectional views showing a method of assembling a vertical type light emitting diode. Figure 5 is a schematic illustration of a laser beam delivery system in accordance with the present invention. 6A through 6C are a perspective view - a top view and a side view of a beam homogenizer in accordance with the present invention. Fig. 6D shows an effective lenslet of a microlens type fly-eye lens used in a beam homogenizer according to the present invention. The photographs and graphs of Fig. 7 show a graph of the intensity of the cross section of a conventional laser beam, which is passed through a mask at the focal plane. The photographs and graphs of Fig. 8 show a plot of the intensity of the cross-section of the laser beam in accordance with the present invention, which is passed through a reticle at the focal plane. TW3624PA/ QP06-QM-002-TW-00 23 1331228 [Description of main component symbols] 2 0 : Rare stone substrate 30: continuous gallium nitride base layer 31: gallium nitride buffer layer 32: N-type gallium nitride layer 33: Activation layer 34: P-type gallium nitride layer 40: trench 50: conductive support layer 60: contact layer 61: interface layer 62: contact pad 100: a conventional beam homogenizer 100 110, 120: cylindrical compound-eye microlens 200 : Laser beam delivery system 210 : Laser source 220 : Beam homogenizer 221 : First fly-eye lens 222 : Second fly-eye lens 223 : Condenser lens 24 TW3624PA / OP06-QM-002-TW-00 1331228 i » : Image Field Lens: Photomask: Imaging Lens: Wafer TW3624PA/ QP06-QM-002-TW-00 25

Claims (1)

1331228 2010/6/10 Amendment 10, the scope of application for patents: 1. A laser beam delivery system comprising: a laser source to emit a laser beam, a beam homogenizer to improve the uniformity of the energy intensity of the laser beam The beam homogenizer includes a microlens type fly-eye lens, the monocular lens having a plurality of small lenses; a reticle to shield a surrounding area of a section of the laser beam, the ray The beam of light is directed through the beam homogenizer at a focal plane; and • an imaging lens to apply the laser beam to a unit illumination area of a target. 2. The laser beam delivery system of claim 1, wherein the beam homogenizer comprises: - a first fly-eye lens to split the laser beam emitted by the laser source into a plurality of small beams, a second fly-eye lens to adjust the dispersion angle of the plurality of small beams; and a concentrating mirror to partially overlap the dispersion angles of the plurality of small beams that have been adjusted. 3. The laser beam delivery system of claim 2, wherein the first fly-eye lens and the second fly-eye lens are both microlens type. 4. The laser beam delivery system of claim 2, wherein the first and second fly-eye lenses have a pitch of 0.5 to 2. Onm. 5. The laser beam delivery system of claim 2, wherein the first and second fly-eye lenses are each a rectangular shape having a horizontal 26 1331228 2010/6/10 corrected length and a vertical length, wherein The ratio of its horizontal length to vertical length is substantially equal to the ratio of the horizontal length to the vertical length of the laser beam cross section. 6. The laser beam delivery system of claim 2, wherein when the focal lengths of the first and second fly-eye lenses are fLA1 and fLA2, respectively, a distance between the first and second fly-eye lenses is greater than fLAi, but less than fLAl+fLA 〇7. The laser beam delivery system of claim 1, wherein the laser beam is a KrF excimer laser beam or an ArF excimer laser beam. 8. The laser beam delivery system of claim 1, further comprising an attenuator for adjusting the power of the laser light emitted by the laser source. 9. The laser beam delivery system of claim 1, further comprising an image field lens between the beam homogenizer and the reticle to adjust between the beam homogenizer and the reticle a distance. 10. A method of transmitting a laser beam, the method comprising: • emitting an excimer laser beam; splitting the emitted excimer laser beam, and emitting the excimer laser beam by a microlens type fly-eye lens Dividing into a plurality of small beam beams, the microlens type fly-eye lens is a monolithic lens having a plurality of small lenses; partially overlapping the plurality of small beams, thereby producing a homogeneous laser beam; shielding the homogeneous laser beam a surrounding area; and causing the masked homogenized laser beam to act on a target. 27 比1228 11·如申社直刹伙网仿, 狮细修正匙括^ u The method described in the first item, 兮方,去·# includes, partially overlapping the complex beam method 4 method more beam Dispersion angle. Then, adjusting the plurality of small meetings 22: 2, the method described in the patent application 1 ,, the back of the basin: = a plurality of small beams including a method of adjusting the plurality of small beam portions / sub-overlapping light 2 Among them, the thunder bundle. + Knife field first beam, arbitrarily ArF excimer laser light 14. The method of claim 1, wherein the laser beam is split into at least 23 small beams. X " 15. The method of claim 1, wherein the effect of concealing the average flb laser beam comprises aggregating the masking homogenized laser beam to impart a precise effect on the laser beam. The method of claim 1, wherein the excimer laser beam is emitted in a pulsed manner. 17. The laser stripping method comprises: forming a nitrogen a gallium delphi layer on a sapphire substrate; emits a quasi-molecular laser beam; and splits the emitted excimer laser beam 'by the microlens type fly-eye lens' to reduce the excimer laser to a small county (4) the microlens type fly-eye lens is a single stone lens having a plurality of small lenses; the portion does not overlap the plurality of small beams, thereby producing a homogenized laser 28 Ί 331228 t 2010/6/10 correction beam; Homogenizing a surrounding area of the laser beam; applying the masked homogenized laser beam to a unit illumination area of the sapphire substrate; and - separating the sapphire substrate by the gasification recording layer. The method of claim 17, further comprising physically separating the sapphire layer from the gallium nitride epitaxial layer. 19. The method of claim 17, further comprising The dispersion angle of the plurality of small beams is adjusted before the plurality of small beams. 20. The method of claim 17, wherein the quasi-molecule laser beam is emitted in a pulsed pattern.