TWI353675B - Manufacturing method of two-dimensional photonic c - Google Patents

Description

1353675 23541twf.doc/〇〇6 IX. Description of the Invention: [Technical Field] The present invention relates to a method for fabricating a two-dimensional photonic crystal in a light-emitting diode, and particularly relates to a disposable A one-shot exposure operation to form a large-area two-dimensional photonic crystal. [Prior Art] ^ Since the luminescence phenomenon of the illuminating diode is not a thermal luminescence or a discharge luminescence, but a cold luminescence, the lifetime of the illuminating diode device can be as long as 100,000 hours or more, and no warming time is required ( Idlingtime). In addition, the light-emitting one-pole device has the advantages of fast reaction speed (about 1 〇·9 seconds), small volume, low power consumption, low pollution (no mercury), high reliability, and suitable mass production, so its application The field is very extensive. In general, the light emitting diode mainly comprises a substrate, a light emitting layer and a plurality of electrodes, wherein the light emitting layer is sequentially stacked by the P type doping layer, the active layer and the N type doping layer. Forming a -potential scale between the type of miscellaneous layer and the p-type doped layer, electrons and fabrics combine in the active layer to generate light. The luminous efficiency of the above-described light-emitting diode mainly depends on the quantum efficiency of the active layer and the extraction efficiency of the light-emitting diode. Among them, the improvement of the quantum efficiency of the active layer mainly depends on the crystal quality of the active layer and its structure, and the efficiency of light extraction depends on the effective utilization of the light emitted by the active layer. In the prior art, many methods for utilizing the surface pattern of the element to improve the light extraction efficiency of the light-emitting body are proposed, such as photonic crystal (photonic 1353675 2354Itwf'doc/006 is a way of seeing, mainly in the light-emitting two A photonic crystal structure is formed in the polar body to change the refractive mode of the light emitted by the active layer to reduce the total reflection of the light and relatively increase the ratio of the light intensity emitted to the outer surface of the light-emitting diode. Therefore, the light of the light-emitting diode can be effectively improved. Extraction efficiency. In recent years, more relevant research has realized the application of two-dimensional photonic crystal (2DPC) on light-emitting diodes. It has been verified that such two-dimensional photonic crystals can be used in light-emitting diodes. The light extraction efficiency provides a better improvement effect. The S-known technology mostly forms the above-mentioned two-dimensional photonic crystal on the surface of the light-emitting layer of the light-emitting diode by electron beam lithography (e_beam lithography) technology. The method requires an electron beam to form a microstructure on the surface of the light-emitting laminate one by one, so the process time is long and the area size of the microstructure is also Will be restricted 'not meeting the needs of actual mass production.

Kim et al., in the journal Appl. Phys. Lett. 87, 203508 (2005), proposes a two-stage holographic exposure (two_step h〇1〇graphic 6 father 511 generation) technique to form a square array (1). ^(^1^111&1_grabbing) the method of two-dimensional photonic crystal of a hole, although it can solve some of the problems of the above-mentioned electron beam process', but since it is necessary to rotate the light-emitting diode in the process, it is The geometric stability of the one-dimensional photonic crystal structure is not good. On the other hand, in terms of manufacturing, it is also important to make a large-area two-dimensional photonic crystal in the light-emitting diode. Topic. In the current report, the area of two-dimensional photonic crystals is mostly about several hundred micrometers (μπι) in length and width. This area is not large enough for mass production applications. 23541twf.doc/〇〇6 [Invention The present invention relates to a method for fabricating a large-area two-dimensional photonic crystal in a borehole, which can improve the light extraction effect of the (four) diode.

The process is simple and can form a two-dimensional photonic crystal with high geometric stability. The invention further relates to an optical system that can be used for large-area two-dimensional optical paths, which can directly provide a large-area two-dimensional interference pattern, to form a large-area two-dimensional photonic crystal having a corresponding lattice arrangement. 9 To specifically describe the contents of the present invention, a method of fabricating an inner two-dimensional photonic crystal is proposed herein. First of all, provide - send Zhao

And forming a layer of photosensitive material on the light emitting diode. Next, at least three light-domain optical material layers are provided, and the above-mentioned money is formed in the photosensitive material layer - a large-area two-dimensional interference _ to expose by the two-dimensional interference pattern. The photosensitive material layer ' of the exposed or unexposed portion is removed to form a mask pattern on the photosensitive material layer. Transferring the mask pattern on the photosensitive material layer to the light-emitting diode / forming a microstructure of a large-area two-dimensional photonic crystal on the 'diode. X. In the present invention - the actual wipe, the transfer cover The method of the curtain pattern to the light-emitting diode is, for example, directly shouting the light material to form a mask to pattern the light-emitting diode, and then removing the photosensitive material layer. In the present invention, the light-reducing material can be further used. Before the layer is formed, the intermediate layer is formed on the light-emitting diode. In addition, the method of transferring the military curtain pattern to the hair-light body is, for example, first patterning the interlayer by using the photosensitive material layer as a mask. Then, The photosensitive material layer is removed, and the patterned intermediate layer is used as a mask to pattern the light-emitting diodes. Thereafter, the intermediate layer 353ύ75 23541 twf.doc/006 is removed. In the embodiment of the present invention, the above microstructure Multiple holes or microcolumns. In addition, the resulting two-dimensional dry, : ί column configuration of the light intensity cycle changes, may include square or three: j case 疋 array row (coherent) ^ ^ 〇 ^ ^

The light intensity distribution of the pattern can be expressed, for example, as: v = (10) shouting, u = 123 where /(W) represents the light intensity of the two-dimensional optical interference pattern in the xy ^ direction 'five represents the electric field strength of the light representing the direction of the light, The initial phase of the ray, the angle representing the polarization direction of the two adjacent human emitters. In one embodiment of the invention, the triangular array period of the two-dimensional interference pattern may be the heart A/tVIsir^/2)], which also represents the wavelength of the light, and 0 represents the angle between the two adjacent incident rays.

In one embodiment of the invention, light is provided on the layer of photosensitive material, for example, by an optical system. The optical system includes a light source, a beam expanding module, a beam splitting module, and an optical lens assembly. The light source can provide a main ray to the beam expander module to obtain a wide beam of light. The expanded light then enters the beam splitting module, splitting the light into three or more broad beams of light. The optical multi-beam light beam is guided onto the photosensitive material layer by the optical lens group ' to form a large-area two-dimensional interference pattern. The invention directly forms a two-dimensional interference pattern by using multiple rays, and is used to make 1353675 23541 twf.doc/006, and the microstructure of the photonic crystal is not only simple and rapid, but also because the 疋 is transferred by the exposure action. The two-dimensional interference pattern makes the formed two-dimensional photonic crystal structure have better geometric stability. The above and other objects, features and advantages of the present invention will become more apparent. The following detailed description of the embodiments of the present invention will be described in detail as follows: [Embodiment] Θ 1, θ. A production process of a two-photon crystal in a light-emitting diode in an embodiment. First, as shown in step UG, a = light-emitting diode is provided, and a layer of photosensitive material is formed on the light-emitting diode. The photosensitive material layer of this ^ can be a generally common positive photoresist material or a negative photoresist material. Next, as shown in step 120, a plurality of rays are provided on the photosensitive material layer, and the light is formed on the photosensitive material layer to form a large-area two-dimensional interference pattern, thereby performing the photosensitive material layer by the two-dimensional interference pattern. exposure. The number of rays described above is usually three or more, which is, for example, light having a high homology to form an effective interference effect. 2 is a two-dimensional interference pattern of a triangular array formed by the present invention, wherein the bright spots 21 〇 represent the positions where constructive interference occurs between the light rays, and the bright spots 21 〇 are arranged in a triangular array. By projecting the two-dimensional interference pattern onto the photosensitive material layer, the photosensitive material layer can be exposed while a corresponding exposure pattern is formed on the photosensitive material layer. " In practical applications, for example, a laser light source can be applied and a large-area two-dimensional interference pattern described above can be formed via the action of optical elements. Fig. 3 is a diagram showing a light source system which can produce a large-area two-dimensional interference pattern according to an embodiment of the present invention. As shown in FIG. 3, the light source system 3 includes a light source 31A, a beam expander module 320, a beam splitting module 330, and an optical mirror group 340. The armor optical module can be composed of a first beam splitting element 33a and a second beam splitting element 33a, and the mirror group 340 can be composed of a plurality of mirrors 34A. The light source 31 is, for example, a laser light source that outputs a laser beam to the beam expander module 32A. Laser light: After the beam module 320, its beam area is enlarged to become the expanded laser light L. The expanded laser light L is incident on the first beam splitting element 33, and the first beam splitting element 330a splits the expanded laser light L into a first light ray L1 and a second light ray L2. The second beam splitting element 33〇b receives the second light line L2 and further splits the second light beam L2 into a third light and a fourth light. The mirror 340a of the optical lens group 340 reflects the first light L1, the third light L3, and the fourth light to the same position of the light emitting diode 350 to form a two-dimensional interference pattern. In the present embodiment, since the first light ray U, the third light ray L3, and the fourth green light L4 are all broad ray rays, a large-area two-dimensional interference pattern can be formed. It is worthwhile to think that the above-mentioned optical system or two-dimensional interference pattern is merely used as an example, and is not the only two-dimensional interference pattern applicable to the present invention or an optical system that can generate two-dimensional interference. After referring to the description of the above embodiments, those skilled in the art can adjust the structure of the optical system, such as the type, quantity and position of the optical components, according to actual conditions, and the formed two-dimensional interference pattern can also be required according to requirements. different. Referring to FIGS. 2 and 3 at the same time, the light intensity distribution of the two-dimensional interference pattern formed above can be expressed, for example, as follows: 1353675 23541twf.doc/006 ί: 2: The two manufacturing methods are only required for the light-emitting diode - Sub-large area two-dimensional photonic crystal structure is also formed

Si, the light extraction efficiency of the diode. Another aspect I invention I: The beam system to obtain a wide beam of light, and can borrow: a two-dimensional: two-dimensional photonic crystal structure. In this way, the production time of the large-area-dimensional photonic crystal can be greatly shortened, which is advantageous for mass production. The text will be further exemplified by the application of the present invention. Please refer to FIG. 6, the luminosity of the present invention - the implementation of luminescence with a two-dimensional photonic crystal: polar body. The light-emitting diode 600 can be a common blue, green, white light photo-polar material, and the example is used to illustrate, but it is not limited to its application range. The light-emitting diode _ mainly includes a substrate _, a light-emitting layer 620, a transparent conductive layer 630, an electrode 642, an electrode 644, an insulating layer 650, and the like. The substrate 610 is, for example, an epitaxial substrate, and the light-emitting layer 62 is placed on the substrate 610, and the two-dimensional photonic crystal 66 is formed on the surface of the light-emitting layer 620. In more detail, the above-mentioned light-emitting layer 62 is composed of, for example, a semiconductor doping layer 622, an active layer 624 and a first semiconductor doping layer 626 from bottom to top, and a two-dimensional photonic crystal. 660 疋 is located on the surface of the uppermost second semiconductor doped layer 626. The transparent conductive layer 630 is located on the surface of the second semiconductor doped layer 626, and the electrodes 642 and 644 are respectively located on the first semiconductor doped layer 622 and the transparent conductive layer 630. Further, the insulating layer 650 is positioned under the transparent conductive layer 630 to separate the electrode 642 from the second semiconductor doped layer 626. 14 C S ) 1353675 2354Itwf.doc/006

In the present embodiment, the first semiconductor doped layer 622 and the second semiconductor doped layer 626 are, for example, an n-type gallium nitride (secret) layer and a gallium ((four)) layer, respectively. (10), the present invention does not (4) the first semiconductor doping layer 622, the first semiconductor doping layer 026, the active layer π4 or even other material layers of the material 'the structure of the light-emitting diode _ shown in Figure 6 is not used Gu Fanshou of the present invention is defined. The two-dimensional photonic crystal can be formed by using the fabrication method of the present invention to improve the luminous efficiency. The main function of the two-dimensional photonic crystal 66 is to change the refraction of light so that the light emitted by the active layer 624 can be smoothly diffused without being totally reflected into the interior of the light-emitting body 600, so that the above two-dimensional photon The light-emitting diode 600 of the crystal 660 will have a higher light extraction efficiency. Figure 7A shows a conventional light-emitting diode (LED) and a light-emitting diode (PCLED) incorporating the photovoltaic photonic crystal of the present invention, which works. Characteristic curve of voltage and driver current. Both of the two types of light-emitting diodes have an area of 1 χ 1 mm 2 . As can be seen from FIG. 7A, the light-emitting diode proposed by the present invention

(PCLED) has a voltage-current characteristic curve similar to that of the conventional one, which can conform to conventional standards. σ In addition, Fig. 7A shows a characteristic curve of driving current and luminous intensity of a conventional light emitting diode (LED) and a light emitting diode (PCLED) of the present invention. As can be seen from Fig. 7B, the luminous intensity of the light-emitting diode (PCLED) of the present invention is twice or more the luminous intensity of a conventional light-emitting diode (LED) under the same driving current. In other words, the technique proposed by the present invention can effectively increase the light extraction efficiency of the light-emitting body and the light-emitting efficiency. 15 23541twf.doc/〇〇6 The heart of the other two Figure 8 shows the traditional light-emitting diodes) disk of the invention first hairpin (PCLED silk distribution, shirt cloth money corner 2 3 two 5 light The intensity is normalized (the one-after the knot can be used to know the ancient material). The two-dimensional photonic crystal of the invention is not only more advanced, but if it is =:), it will help to improve the display. = (: The present disclosure has been disclosed above by way of example. However, it is not intended to limit the ordinary knowledge in the field of God 2, and without any departure from the present invention, when a little change and refinement can be made, Therefore, the present invention [as defined in the appended patent application scope. The photon-embodiment of the two-dimensional pattern in the light-emitting diode Figure 2 shows the two-dimensional interference of a triangular array formed by the present invention. Dry 剌 — 实施 实施 实施 实施 实施 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 可 - - - - - - - - - - - - - - - - - - - - - - Schematic diagram of the process of the sub-crystal. The invention of the invention - the implementation of the species has a two-dimensional photonic crystal 1353675 23541twf.doc / 006 Figure 7A The luminous diode of the traditional light-emitting diode and the sister crystal is shown, and the two-dimensional light diagram of the # 〇 发 发 示 示 示 示 示 示 示 示 示 示 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征 特征The light-emitting diode of Figure 4 shows the traditional 孓-emitting diode and the light-emitting type distribution. The light-emitting diode of X

[Description of main component symbols] 210: Highlights d: Period of two-dimensional interference pattern 300: Light source system 310: Light source 320: Expanding module 330: Beam splitting module 330a, 330b: Beam splitting element 340: Optical mirror group

340a: mirror 350: light-emitting diodes L, L1 to L4, L': light: any two adjacent rays have an angle 410: light-emitting diode 410a: two-dimensional photonic crystal 420: photosensitive material layer 422: after exposure Part of the photosensitive material layer 420a: mask pattern 17 1353675 23541twf.doc/006 510: light-emitting diode 510a: two-dimensional photonic crystal 520: photosensitive material layer 522: exposed portion of photosensitive material layer 530: intermediate layer 520a, 530a: first mask pattern 600: light emitting diode 610: substrate 620: light emitting layer 622, 626: semiconductor doping layer 624: active layer 630: transparent conductive layer 642: electrode 644: electrode 650: insulating layer 660: Two-dimensional photonic crystal 18

Claims (1)

1353675 * * | ρ年月月 修日修 (more) 正 ii〇0'3'2 X. Patent application scope: 1. - A method for producing two-dimensional photonic crystals in a light-emitting diode, including: providing a light a diode-forming photo-sensitive material layer on the light-emitting diode, wherein the photosensitive material layer is one of a positive-type photoresist material and a negative-type photoresist material; providing at least two light rays on the photosensitive material layer, And causing the light to form a two-dimensional interference pattern on the photosensitive material layer to expose the photosensitive material layer by the two-dimensional interference pattern +, wherein the light is laser light; if the photosensitive material layer is positive The photoresist material removes the photosensitive material layer of the exposed portion. If the photosensitive material layer is a negative photoresist material, the unexposed portion of the photosensitive material layer is removed to be on the photosensitive material layer. Forming a mask pattern; and transferring the mask pattern on the photosensitive material layer onto the light emitting diode to form a microstructure of the two-dimensional photonic crystal on the light emitting diode. 2. The method according to claim 2, wherein the method of transferring the mask pattern onto the light emitting diode comprises: patterning the photosensitive material layer as a mask a light emitting diode; and removing the photosensitive material layer. 3. The method for fabricating a two-dimensional photonic crystal according to claim 1, further comprising forming an intermediate layer on the light-emitting diode before forming the photosensitive material layer, wherein the intermediate layer is sensitive to the light-emitting diode The material layer and the hair 19 1353675 100-3-2 photodiode have an etching selection effect. 4. The method for the two-dimensional photonic crystal described in U.S. Patent No. 3, wherein the t-transfer material 瞧(10) is on the illuminating diode: the photographic material layer is used as a mask to pattern the An intermediate layer; removing the photosensitive material layer; patterning the light emitting diode with the patterned intermediate layer as a mask; and removing the intermediate layer. The hometown (4) refers to the method of making a traitor, and the microstructure includes a plurality of holes or microcolumns arranged in an array. 6. As in the production of the two-dimensional photonic crystal described in item 5 of the patent application, Xuan _ _ squama striate changes, in order to form the array of the holes or micro-columns strong and weekly. For example, in the method described in the scope of claim i, the + is performed on the layer of the eleventh day of the eleventh day, and the first is Lt: the first line is provided for the photosensitive material: the main line ' The chief ray is a laser beam; the beam expanding module enlarges the beam of the incident chief ray. The main priming knife first becomes at least three rays; and the optical mirror group is configured to illuminate the light puncturing material layer. . 20 1353675 23541TW_J 110 120 130 140 1353675 23541TW-J S) 1353675 23541TV/.J 420 410 420 410 Figure 4B ΓΊΓΊΓΊΠΓΊΓΊΓΊΠ 420α 420 410 Figure 4C Figure 4D 420α 420 410 410α Figure 4Ε 410 1353675 m vuiw^i^^aemiM%mMV.Mt--^=: Figure 5A Figure 5B - 520 • 530 - 510 520α imnnnnnrnnf Figure 5C 1353675 23541 TW_J 520α 520 530 510 Figure 5D 530α 530α 530 510 Figure 5Ε 530α 530 510 Figure 5F 510α 510α Figure 5G 1353675 23541 TW_J 642 620 [626 624 622 644 610 600 1353675 GQ ffi (•n*D) mm Id——Gywl®—I (yuu) r-MLlscOJ 1353675 23541TW_J ----Traditional IID PCLED Angle (Deg.) β ι