KR101075940B1 - Led chip device structure, method for manufacturing the same, and led chip device obtained by the method - Google Patents

Abstract

According to the present invention, there is provided a diffraction grating structure having a concave-convex pitch of 300 nm or less on the surface of an LED chip element, the structure of the LED chip element and a method of manufacturing the LED chip obtained thereby An element is provided.

LED, irregularities, diffraction, nano

Description

LED CHIP DEVICE STRUCTURE, METHOD FOR MANUFACTURING THE SAME, AND LED CHIP DEVICE OBTAINED BY THE METHOD

The present invention relates to a structure of an LED chip element capable of increasing the luminous efficiency of the LED chip element, a manufacturing method thereof, and an LED chip element obtained thereby.

In order to improve the luminous efficiency of LED chip devices, methods such as chip device structure improvement, color material improvement, and substrate reflection performance have been mainly developed.

However, the development method of the surface of the LED chip device has not been developed very effective. In improving the surface of a chip element, the improvement of efficiency by raising the surface area by roughening the surface of a chip element is already generalized.

The present invention can provide a structure of a LED chip device having a high luminous flux output efficiency and a method of manufacturing the same, which are obtained by modifying a chip surface.

An object of the present invention is to design a diffraction grating structure, such as an approximately rectangular parallelepiped, a cuboid, or a cylindrical, having an uneven pitch of 300 nm or less on the surface of a wafer substrate as an LED chip element, thereby improving the light emission efficiency of the light emitted from the LED chip element. The present invention provides a structure, a method of manufacturing the same, and an LED chip device obtained thereby.

The structure of the structure of the LED chip element according to an aspect of the present invention for achieving the above object is formed on the surface of the LED chip element is a diffraction grating structure of 300 nm or less in pitch.

Preferably, the unevenness has any shape selected from the group consisting of a cube, a cube and a cylinder.

Preferably, the diffraction grating structure is formed on a GaP wafer substrate.

Preferably, the LED can be applied to a red LED of AlGaAs.

According to another aspect of the present invention, a method of manufacturing an LED chip device structure is provided.

(a) making a roll transfer mold in which a plurality of irregularities having a pitch of 300 nm or less are continuously formed;

(b) transferring the uneven shape processed on the roll transfer type surface to a plastic film to form an uneven transfer film;

(c) applying a photosensitive material such as UV-curable to the concave-convex surface of the concave-convex transfer film made in step (b), and then drying to form a layer to form a laminated film for resist;

(d) laminating the laminated film for resist made in step (c) on the wafer substrate to be an LED chip element, irradiating UV from the outside of the laminated film for resist to cure the photosensitive material, and transferring the uneven projections Peeling the film from the cured photosensitive material to form a photosensitive material cured layer having a concave-convex structure on the wafer substrate to be the LED chip element; And

(e) The uneven shape is etched to a depth of 500 nm or less on the wafer substrate to be the LED chip element on which the uneven photosensitive cured layer is formed, and after etching, the unnecessary photosensitive material is removed to form the LED chip element on the wafer substrate. Forming a diffraction grating structure having an uneven pitch of 300 nm or less.

Preferably, the uneven shape is any one selected from the group consisting of a cube, a cube and a cylinder.

Preferably, in the step (b), the plastic film is made of any one material selected from the group consisting of polyolefin, polyvinyl chloride and biaxially stretched polyethylene terephthalate.

Preferably, in step (c), the release film is coated on the surface of the photosensitive material, and the release film is peeled off before laminating on the wafer substrate in step (d).

Preferably, the step (b) is to apply the UV curable resin on the transfer film, in the state of contacting the surface of the UV curable resin coated on the transfer film in the roll transfer type, the roll transfer type and UV irradiation is performed on the opposite side of the surface of the transfer film in contact to transfer the opposite shape of the concave-convex shape to the surface of the transfer film to form an uneven transfer film.

Preferably, the UV curable resin is coated with a roll coater, a spin coater, a spray, a dipping coater, a wire bar coater, and gravure. The coating is applied using any one method selected from the group consisting of coater coating and air knife coater coating.

Preferably, the UV curable resin, 50 parts by weight of UA1 (urethane-based oligomer (average molecular weight: 7,000)), 50 parts by weight of 4EG-A (tetra ethylene glycol diacrylate (bifunctional monomer)), and photoinitiator (1 2 parts by weight of hydroxy cyclohexyl phenyl ketone).

Preferably, in step (d), the etching is performed using a reactive ion etching apparatus.

Preferably, in step (d), the unnecessary photosensitive material is removed by washing or ICP-RIE process using O2 gas.

Preferably, the photosensitive material is a polymer of negative shape or positive shape.

Preferably, the polymer is Polymer A using styrene, methyl methacrylate, ethyl acrylate, acrylic acid, glycidyl methacrylate copolymer resin.

Preferably, the photosensitive material is 70 parts by weight of polymer A, 30 parts by weight of pentaerythritol tetra acrylate (monomer), 2.2 parts by weight of Irgacure 369 (initiator), N, N-tetraethyl-4, 4'-dia 2.2 parts by weight of minobenzophenone (initiator), 492 parts by weight of propylene glycol monomethyl ether (solvent), 0.1 part by weight of p-methoxyphenol (polymerization inhibitor) and 0.01 part by weight of perfluoroalkyl alkoxylate (surfactant) Include.

An LED chip device according to another aspect of the present invention is obtained by cutting a wafer substrate having a LED chip device structure obtained by the method described above to a predetermined size.

At least 300 nm in height and 300 nm in pitch formed on the surface of the roll transfer die, roughly rectangular or cubic or cylindrical, such as roughly rectangular, cubic or cylindrical, in which a plurality of concave or iron shapes are continuously arranged, It differs from the shape of the diffraction grating structure formed on the wafer substrate which becomes an LED chip element, and becomes shallower than the predetermined depth of the diffraction grating formed on the wafer substrate for LED chip element. Reactive ion etching is one of microfabrication techniques classified into dry etching.

In principle, in the reaction chamber, an electromagnetic wave or the like is applied to the etching gas to make a plasma, and at the same time, a high frequency voltage is applied to the cathode having the sample. As a result, a self bias potential is generated between the sample and the plasma, and ions and radicals in the plasma accelerate and collide in the sample direction. At this time, sputtering by ions and chemical reaction of etching gas occur simultaneously, and etching is performed at a high degree suitable for micromachining.

As the RIE etching gas, based on tetrafluorocarbon CF ₄ , H ₂ , which is easy to react with fluorine and whose reaction product is expected to be volatile or easily desorbed, is added, and the flow rate of H ₂ gas to CF ₄ gas is added. The etching rate of each of the resist film and the SiO ₂ film can be changed by changing the mixing ratio. Moreover, a general UV hardening resin can be used for the photosensitive material used as a resist material.

When the H ₂ gas flow rate mixing ratio is about 30% or more with respect to the tetrafluorocarbon CF ₄ of the RIE etching gas, the resist film is hardly etched. In other words, the use of a thinner resist film compared to the dielectric film serving as an etch stop mask means that the resist pattern can be accurately transferred.

In addition, the depth of the concave-convex shape etched in the SiO ₂ film can be formed deeper than the depth of the concave-convex surface of the resist film.

The present invention provides a conventional photomask by laminating and UV-curing a transfer laminated film (photosensitive material coated product), which has been continuously manufactured by a roll process on a wafer substrate to be an LED chip element, onto a wafer substrate to be an LED chip element. Compared to the photo mask method, the process can be greatly shortened and a resist film for RIE processing is formed in a simple process.

RIE treatment is performed on a resist film formed on the wafer substrate to be the LED chip element, and a diffraction grating structure is formed on the surface of the wafer substrate for ELD chip element. The present invention can easily form a diffraction grating structure such as a rectangular parallelepiped, a cube, or a cylinder having an uneven pitch of 300 nm or less on a wafer substrate to be an LED chip element.

Since the diffraction grating can increase the amount of light emitted from the LED chip element as the first-order diffracted light described later, the light emission efficiency of the LED can be increased.

According to the present invention, the diffraction grating structure 9 can be formed on a wafer substrate 7 to be an LED chip element by a good and repeatable process, and the GaP type LED chip element 26 can be processed. It is possible to provide a structure and a method of manufacturing the same that can increase the light output efficiency in terms of 2.3 times.

The present invention will be described with reference to the drawings.

1 shows the roll transfer die 1 of the present invention. The shape may be yoga or iron, but the present description is described as a yaw shape. Since the depth and shape of the yaw also depend on the conditions of the RIE, it is necessary to set the shape in advance by experiment. Since this is not a subject of the present invention, it is omitted.

The outline process drawing until producing the roll transfer die 1 is shown in FIG.

The uneven shape spin-coats an electron beam resist (ZEP520: JAPAN ZEON) on the Si wafer substrate 27 to form a resist film 6 having a predetermined thickness.

Next, the pattern is drawn using an Electron Beam Recorder (EBR) device. As shown in FIG. 3, dots 100 mm in diameter, 200 nm in pitch, and 100 nm in thickness were formed. This shape may be roughly a cube or a cube.

Next, the resist film 6 was developed by the dipping method. The material used was ZED-N50 (Japan Zeon).

Next, an inductively coupled plasma (ICP) RIE apparatus 8 is used to form a yaw shape such as a cylinder.

In the etching conditions, a yaw shape such as a cylinder or the like was formed on the Si wafer substrate 27 by an ICP-RIE process using CF ₄ gas. The process was 30 sccm, the pressure was 0.5 Pa, and etching power was 80W.

The ICP-RIE apparatus 8 etches the Si wafer substrate 27 so that the depth of the 100 nm cylinder is 400 nm. After 400 nm etching, the resist film 6 is removed by an ICP-RIE process using O ₂ gas.

An Ag layer 28 is formed on the concave surface such as a cylinder formed on the Si wafer substrate 27 by the electroless plating method 54 to form a conductive layer of the Ni electroplating method.

An electroless plating method on which the Ag layer 28 was formed on the Si wafer substrate 27 was put in the Ni electroforming casting 36 and subjected to Ni electroplating. If the Ni electroplating layer 37 having a predetermined thickness is formed by this Ni electroplating, the Si wafer substrate 27 is taken out of the Ni electroforming bath 36. The uneven surface 30 of the electroplated surface of the Ni electroplated layer 37 is cut with a diamond bite planar processing machine 31 to smooth the plated surface of the non-plated surface of the Ni electroplated layer 37 and the Ni electroplated layer 37. Is a predetermined constant thickness. Thereafter, the Ni electrode layer 37 is peeled off from the Si wafer substrate 27 to produce a master electrode mold 29. By repeating this operation, the predetermined number of master electroforming molds 29 are placed on the glass substrate 32 whose surface is polished and smoothed, and adhesively fixed with a thermosetting adhesive such as epoxy.

The Ni electroplating layer 36 is then placed in the Ni electroforming die 36 to form a Ni electroforming layer 37 with a predetermined thickness. As in the case of the master electroforming die 29, the electroplating of the Ni electroforming layer 37 is a diamond bite. It cuts with a planar processing machine, makes the electroplating back surface smooth, and makes Ni electroplating layer 37 into predetermined fixed thickness.

The terminal of the strip | belt-shaped Ni electroplating layer 37 used as the roll transfer die 1 produced by this is welded, and the strip | belt-shaped roll transfer die 1 as shown in FIG. 1 is produced.

3 shows the legend shape of the yaw shape 38 applied to the roll transfer surface.

The uneven shape 38 of the roll transfer type is shallower than the diffraction grating structure 9 formed on the wafer substrate 7 serving as the LED chip element.

As a result, as described above, the resist film 6 is hardly etched by the etching gas selection of the RIE. That is, it is because the depth of the concave-convex shape etched in the SiO ₂ film can be deeper than the depth of the concave-convex depth of the resist film 6.

Next, the process of making the uneven transfer film 4 is demonstrated.

It is preferable that the plastic film 2 used as the uneven transfer film 4 is deformable, chemically and thermally stable. Examples of the material of the plastic film 2 include polyolefin, polyvinyl chloride, biaxially stretched polyethylene terephthalate, and the like. Among these, the most preferable is biaxially stretched polyethylene terephthalate which is excellent in dimensional stability.

4 shows an apparatus for manufacturing the uneven transfer film 4.

In the figure, (2) shows the supplied plastic film, and (16) shows the UV curing resin supply device. This device is a device for supplying a certain amount of UV resin 3 to be applied to the plastic film 2 accurately. 10 denotes a feed speed control roll, and 1 denotes a roll transfer type. Denoted at 12 is a UV lamp to cure the UV curing resin 3. (17) is for making the coating amount of the UV hardening resin 3 constant with a UV hardening resin gap roll. 11a and 11b point to a gap control roll, and are for making the UV hardening resin 3 apply | coated to the uneven transfer film 4 into a uniform thickness. (15) indicates a gap plate. This is to make the thickness of the UV hardening resin 3 more uniform. Denoted at 13 is a winding speed control roll on the tension side, and indicated at 14.

The said roll transfer die 1 is strip | belt-shaped made by Ni plating method, and becomes the speed | rate synchronized with the conveyance speed of the plastic film 2. As shown in FIG. The yaw shape as shown in FIG. 3 is designed in the surface of this roll transfer die 1.

The plastic film (2) is conveyed in the apparatus while the speed is controlled via the feed rate control roll (10), the UV curable resin (16) is uniformly coated on the surface of the plastic film (2) by the UV curable resin supply device (16) do. The roll transfer die 1 and the plastic film 2 are sandwiched between the gap control rolls 11a and 11b and the gap plate 15, and the UV lamps on the opposite side of the plastic film 2 to which the UV curable resin 3 is applied. 12), and the UV cured resin (3) was UV cured. Thereby, the uneven transfer film 4 can be manufactured continuously.

Since the uneven shape 38 of the roll transfer die 1 can be accurately formed on the surface of the uneven transfer film 4 by the manufacturing method according to this embodiment, the resist film 6 of the RIE apparatus 8 used later is By increasing the degree of thickness, the reproducibility of the diffraction grating structure 9 formed on the wafer substrate 7 for LED chip elements can be improved as a result.

In the present invention, the plastic film 2 may be made of polyolefin, polyvinyl chloride, biaxially oriented polyethylene telephthalate, or the like.

The UV hardening resin 3 can add a photoinitiator, the monomer which has an ethylene double bond, etc. beforehand. As the photosensitive type, either a negative shape material or a positive shape material may be used.

As a coating method of the UV curable resin (3) used in the present invention, roll coater coating, spin coater coating, spray coating, dipping coater coating, wire bar coater bar coater coating, gravure coater coating, and air knife coater coating.

5 is a cross-sectional view showing an example of the uneven transfer film 4 laminate in the present invention. The uneven UV cured resin layer 18 to which the uneven shape is transferred onto the plastic film 2 is laminated.

As the uneven UV-curable resin layer 18 in the transfer laminate, a deformable organic polymer, a composition containing the same, and the like can be used, but an organic polymer that can be wound into a film or a composition thereof is preferably used.

The uneven UV curable resin layer 18 is not particularly limited in hardness, refractive index, and spectral transmittance.

The UV hardening resin 3 can use either the negative photosensitive type material or the positive shape material which are commercially available. For example, the following components can be used.

Table 1. Composition of UV Curing Resin

ingredient Ratio (part by weight) UA1 (urethane oligomer (average molecular weight: 7,000)) 50 parts by weight 4EG-A (tetra ethylene glycol diacrylate)
(Kyoeishya, bifunctional monomer)) 50 parts by weight Photoinitiator (1-hydroxycyclohexylphenyl ketone
(Chiba specialty chemicals, brand name; Irgacure184)) 2 parts by weight

The uneven transfer film 4 obtained by this is used, and the photosensitive material material 5 is apply | coated to this uneven UV hardening resin layer 18 surface in a next process.

As a polymer of the photosensitive material to apply | coat, either a commercially available negative shape material or a positive shape material can be used.

Examples of the polymer include styrene, methyl methacrylate, ethyl acrylate, acrylic acid, glycidyl methacrylate copolymer (polymer A). The molecular weight is about 35000 and the acid value is 110. Parts by weight (the same as below)

Table 2. Photosensitive Material Blend

ingredient ratio Polymer A 70 parts by weight Pentaerythritol tetraacrylate (monomer) 30 parts by weight Irgacure 369
(Chiba specialty Chemicals brand name) (initiator) 2.2 parts by weight N, N-tetraethyl-4,4'-diaminobenzophenone (initiator) 2.2 parts by weight Propylene Glycol Monomethyl Ether (Solvent) 492 parts by weight p-methoxyphenol (polymerization inhibitor) 0.1 parts by weight Perfluoroalkylalkoxylates (surfactants) 0.01 parts by weight

The uneven UV-curable resin layer 18 of the concave-convex transfer film 4 is coated with a comma coater so as to have a film thickness of 1 μm or less using a comma coater. Then, it is dried. After drying, a protective film 19 such as a polyethylene film is coated for the purpose of dust adhesion and scratch prevention.

Thereby, the laminated | multilayer film for RIE resists 20 of the cross-sectional structure shown in FIG. 6 can be manufactured continuously.

The protective film 19 of the RIE resist laminated film 20 is peeled off, and the photosensitive material 5 surface of the RIE resist laminated film 20 is formed on the wafer substrate 7 serving as the LED chip element. Lamination is carried out using a laminator so as to contact the wafer substrate 7. At this time, preferably, the temperature of the wafer substrate 7 serving as the LED chip element is preferably 50 ° or more. The layer of photosensitive material 5 laminated on the wafer substrate 7 to be an LED chip element is opposite to the surface of the photosensitive material material 5 of the laminated film 20 for RIE resist, that is, the laminated film 20 for RIE resist. Irradiate with the UV lamp 12 from the outside of, and UV-curing the photosensitive material (5). Thereafter, the resist film 6 and the uneven transfer film 4 obtained by curing the photosensitive material 5 are peeled off to form a resist film 6 on the wafer substrate 7 serving as an LED chip element.

The laminated product of the resist film 6 formed on the wafer substrate 7 serving as the LED chip element is set in the RIE apparatus 8 in FIG. 7 and dry etched. These process outlines are shown in FIG.

BACKGROUND OF THE INVENTION Reactive ion etching (RIE) devices are used for etching devices in semiconductor manufacturing processes because high productivity can be obtained by synergistic effects of physical sputtering of ions and chemical etching of radicals.

As a mechanism of the reactive ion etching apparatus, an activated gas having a pressure of 1-100 Pa is introduced into an etching chamber evacuated, and an active gas plasma is generated in a room by plasma generation means such as high frequency, and the ion generated by separation of the active gas and Etching is done by bringing radicals to a wafer placed on an electrode. Many methods have been developed for a reactive ion etching (RIE) apparatus, such as a batch type process for processing a plurality of wafers simultaneously and a high-speed sheet type process for processing wafers one by one. 9 shows a schematic diagram of a production RIE apparatus. The vacuum chamber of the reactive ion etching apparatus includes an etching chamber 40, a transfer chamber 41, a rod chamber 42, and an unload chamber 43, which are each divided by gate valves 44. In the case of the two-room structure, a plurality of wafer substrates for LED chip elements before etching are stored in the load chamber 42 and sent to the etching chamber 40 by the vacuum robot 45 placed in the transfer chamber 41 under vacuum. Lose. At the end of etching, the vacuum robot 45 is similarly taken out and sent to the unload chamber 43.

Of course, it is also possible to use four to two to three chambers, depending on the purpose and size of the device. Since there is no need to do so, not only the productivity improvement by shortening of access time but also stabilization of an etching characteristic are connected.

Gas introduction into the etching chamber 40 is controlled by the massflow controller 46, and the operating pressure is adapted to control the exhaust velocity and maintain a predetermined pressure because the etching characteristics are affected by the gas flow rate. The exhaust gas has a turbomolecular pump 47 or the like, and the control during the exhaust gas control the opening degree of the conductance variable valve 48 on the inlet side.

The equipment used in this process includes heating, corrosion resistance, and reaction products to prevent clogging of gas that is liable to be condensed at room temperature such as SiCl ₄ and CCl ₄ which are frequently used as RIE. In addition, these process gases and reaction products are discharged to a pump such as a dry pump 49 through a turbo molecular pump 47 or the like.

Microfabrication technology in semiconductor devices or magnetic devices generally consists of two processes: lithography technology and etching technology. Etching techniques include a wet etching method and a dry etching method using a low vacuum plasma. In general, the latter is superior to the former in the degree of processing, the anisotropic processing according to the direction of the plasma, and the adhesion between the mask and the workpiece. In particular, when reactive species (CF ₄ , CCl _4, etc.) are reacted in the plasma with the surface of the workpiece, volatile reaction products CF ₄ , CCl _4, etc. use halogens to generate halogen compounds. Reactive ion etching (RIE), which is etched by removing it from the surface, is widely used as a technique for realizing finer processing, and has been greatly developed as a basic technology in the microfabrication process of various semiconductor devices including silicon ultra LSI. .

As an example of micromachining, since CO gas is disproportionately decomposed into carbon single particles and carbon dioxide molecules in the plasma, it is difficult to obtain active species of CO even when plasma is converted to CO gas. The etching does not proceed because it reacts with the element to form a transition metal carbide and protects the magnetic surface. In view of the fact that ammonia gas (NH ₃ ) has a function of inhibiting the decomposition of CO gas in the presence of transition metal, NH ₃ gas is added to the CO gas, thereby increasing the etching rate and improving the selectivity to the magnetic metal material. I could see that. Moreover, it is known that it is effective for the micromachining of a magnetic metal material, for example, to obtain a fine line grating | lattice of a sharp shape.

CO gas and NH ₃ gas are introduced in a vacuum, and they are excited at high frequency to generate plasma thereof, and a metal magnetic material is placed in the atmosphere with a thin film of the magnetic metal material of the material to be processed. Selectively etching only the material. This is also effective for fine processing of conductive materials such as gold and copper. By using a vacuum-resistant metal material with resistance to corrosion, such as titanium, in the construction of the RIE device, it is possible to prevent problems such as corrosion of the device and contamination of the workpiece, and to allow ultra-fine processing of magnetic metal materials. Lose.

In order to realize the optimum processing conditions excellent in the high aspect and high smoothness obtained from the nanostructure, a resist pattern formed by electron beam exposure or reduced projection sputtering exposure is transferred to a dielectric film such as silicon dioxide SiO ₂ or silicon nitride SiN serving as an etching mask. High-precision resist pattern transfer technology that can be accurately transferred to high dimensional accuracy is also omitted. RIE using carbon fluoride gas is widely used, but the improvement of the transfer degree requires improvement of the etching rate ratio (selectivity) of the resist film and the dielectric film, and the thinning of the resist. I think it will be a point.

As the etching gas, H ₂ , which is easy to react with fluorine based on tetrafluorocarbon CF ₄ , is expected to be volatile or easily desorbed, and H ₂ gas to CF ₄ gas is added. It is also known to vary the flow rate mixing ratio to vary the etching rate of each of the resist film and the SiO ₂ film. As the resist material, both negative and positive types can be used. When the H ₂ gas mixture flow rate ratio is 0%, the etching rate between the SiO ₂ film and the resist film is almost 1: 1, i.e., almost no selectivity, and is not very suitable for the condition that the resist pattern is transferred to the SiO ₂ film with high accuracy. .

In addition, as the flow rate mixing ratio of the H ₂ gas was increased, the etching rate of the resist film tended to decrease significantly, while the etching rate decrease of the SiO ₂ film was less than that of the resist film, and there was no significant change. It is also known that the resist film is hardly etched when the H ₂ gas flow rate mixing ratio is about 30% or more.

As a result, it is possible to use a thinner resist film as compared to the dielectric film serving as an etching mask, and thus, the resist pattern can be transferred with high precision, and the nanostructure can be transferred with a high precision resist pattern.

As a result, an excellent diffraction grating structure 9 can be formed on the wafer substrate 7 serving as the LED chip element.

In the nano-concave-convex structure, diffraction does not occur because it is an antireflection structure within the critical angle. The conditions under which the first order diffraction occurs at a wider angle than the critical angle can be estimated by the following equation.

In the diffraction grating structure as shown in Fig. 10, an appropriate unevenness interval was obtained from equation (1) of diffraction. The diffraction equation can be given as follows.

sinθ _k d-n _G sinθ _i = kλ / m (m = 0, ± 1, ± 2) (1)

(n _G : refractive index of GaP (3.2), θ _i : incident angle, θ _k : exit angle, λ: wavelength, d: gap of diffraction grating, k: diffraction order, diffraction order k is -1)

Table 3 shows the calculation results of the incident angles at which the light ray 50 can be emitted from the LED chip element 26 of the first diffraction light obtained by the equation (1).

Table-3.

Lattice spacing d (nm) 100 150 200 300 600 The outgoing angle of incidence of the first diffracted light (°) none 69-90 39-90 18-69 0-38

The diffraction did not occur when the gap between the irregularities was about 100 nm. It was found that diffraction in which the light beam 50 can be emitted from the LED chip element 26 occurs at an incidence angle of more than 18 ° at grain boundary intervals of 150, 200, and 300 nm. Moreover, at 600 nm where the unevenness interval is the same as the wavelength, the diffraction angle is within 38 °, which is not suitable. Therefore, it can be seen that the optimum unevenness interval of the uneven structure is around 200 nm.

By forming the diffraction grating structure 9 on the LED chip element wafer substrate 7 used for the LED chip element 26 as described above, the amount of light output from the LED chip element 26 is increased to achieve high luminance. The structure of the LED chip element 26 and its manufacturing method can be provided.

(Example)

As an example, an open cylindrical concave-convex shape 51 shown in Fig. 11 having a width of 100 nm, an interval of 200 nm, and a height of 100 nm was formed on the Si wafer substrate 27 by 8 inches by RIE dry etching.

This uneven shape 51 can also be formed by various methods, such as electron beam drawing, 3D laser exposure, and the photolithographic method.

The characteristic of this uneven shape 51 was described in the above-mentioned FIG. It is a feature of the present invention that it can be made significantly shallower than the depth of the diffraction grating structure 9 formed on the wafer substrate 7 of the LED chip element cell.

Mass production is possible with the film which made the resist film 6 formed on the wafer substrate 7 of the cell for LED chip elements continuous, and the uneven | corrugated UV hardening of the uneven transfer film 4 shown to FIG. 5 and FIG. It is a point that the depth of the uneven | corrugated shape of the resin layer 18 can fully be transferred.

A conductive layer for forming an Ag plating layer 28 by electroless plating on the uneven surface side of this 8-inch Si substrate 27 as shown in Figs. 2A and 2B described above, and producing a master electroforming mold 29. It is done.

Ni electroplating was carried out in the Ni electroforming casting 36, and the master electroforming die 29 was produced. In the Example, the thickness of the master electroforming die 29 was 200 m.

After completion of the electric pole, electric pole back surface irregularities 30 are cut with a diamond bite planar processing machine 31 to make the smoothness and thickness of the back surface constant.

This process is repeated to produce a predetermined number of master electroforming molds 29.

In the embodiment of the present invention, the master pole mold 29 thus obtained is disposed on the glass substrate 32 as shown in FIG. ).

An Ag layer 28 is formed in this master electroforming continuous batch type 33 by electroless plating, and a roll transfer die 1 is produced by Ni electroplating.

This roll transfer die 1 is attached to an apparatus for producing the uneven transfer film 4 shown in FIG. 4 described above.

The plastic film (2) used a PET film of the type to which Toyobo A4300 50 micrometer-thick UV resin etc. are easy to adhere | attach. This plastic film 2 is attached to the apparatus for manufacturing the uneven transfer film 4, and is brought into contact with the preceding roll transfer die 1 through the feed speed control roll 10 and the gap control rolls 11a and 11b. The plastic film 2 is arrange | positioned. Furthermore, it winds around the winding device 14 via the winding speed control roll 13. That is, the above-mentioned plastic film 2 is speed-controlled via the feed speed control roll 10, and has a structure conveyed into an apparatus. The UV curable resin supply device 16 supplies UV curable resins having the composition shown in Table 1 above.

UV curable resin of the said composition is precisely supplied to the UV curable resin supply apparatus 16 on the plastic film 2, and it apply | coats so that it may become 10 micrometer thickness on the plastic film 2 surface.

The applied UV cured resin 3 is further sandwiched by the gap control rolls 11a and 11b and the gap plate 15 to make the coating thickness of the UV resin 3 homogeneous.

In this state, light is irradiated with the UV lamp 12 on the outside of the plastic film 2 on the opposite side to which the UV resin 3 is applied, and the UV resin 3 is cured, and the roll transfer mold 1 surface The concavo-convex shapes having a diameter of 100 nm, an interval of 200 nm, and a height of 100 nm shown in Fig. 11 are continuously transferred. Thereby, the uneven transfer film 4 in which the uneven shape is continuously formed on the plastic film 2 can be produced. This is wound up by the winding-up device 14.

In order to accurately transfer the uneven shape of the roll transfer die 1, the feed rate of the feed speed control roll 10 and the take-up speed control roll 13 and the feed rate of the plastic film 2 of the roll transfer die 1 at a synchronized speed. It is.

According to the manufacturing method according to this embodiment, since the pattern of the roll transfer die 1 can be accurately transferred to the UV-curable resin 3, the forming degree is high, and this height is the resist of the RIE apparatus 8 used later. The degree of the thickness of the layer 6 can be increased and the reproducibility of the diffraction grating structure 9 can be improved.

The UV hardening resin 3 can add a photoinitiator, the monomer which has an ethylene double bond, etc. beforehand. As the photosensitive type, either a negative shape material or a positive shape material may be used.

The coating method of the UV curable resin 3 used in the present invention includes roll coater coating, spin coater coating, spray coater coating, dipping coater coating, wire bar coater coating, gravure coater coating, air knife coater coating, and the like. Since this is not a subject, detailed explanation is omitted. In this example, roll coater coating was used.

Thereby, the laminated body of the uneven transfer film 4 shown in FIG. 4 mentioned above can be manufactured continuously.

It is preferable to use the organic polymer which can be wound in a film form, or its composition as the uneven UV hardening resin layer 18 in the said transfer laminated body.

Next, the photosensitive material 5 of the composition solution shown in Table 2 was formed on the surface on which the uneven shape transfer film 4 produced as described above was formed with a comma coater. After applying so that the propylene glycol monomethyl ether (solvent) was dried and evaporated.

As a result, a layer of photosensitive material 5 having a thickness of about 0.15 or less is formed on the uneven surface of the uneven transfer film 4. After evaporating the solvent of this photosensitive material 5 layer, the polyethylene film is coat | covered with the release film 19 on it, and the surface of the photosensitive material 5 is protected.

In this process, the laminated film 20 for RIE resist can be manufactured continuously.

Next, as shown in FIG. 8 described above, the protective film 19 of the RIE resist laminated film 20 is peeled off and laminated on the wafer substrate 7 for LED chip elements.

The laminate uses a laminator (roll laminator) and laminates the photosensitive material 5 layer on the wafer substrate 7 for LED chip elements at a roll temperature of 85 °, a roll pressure of 8 kg / cm 2, and a speed of 1.0 m / min. Thereafter, UV irradiation is performed on the outside of the laminated film 20 for REI resist with a UV lamp 12, and the photosensitive material 5 is UV cured to form a resist film 6.

Next, the uneven transfer film 4 layer is peeled off from the wafer substrate 7 for LED chip elements. Thereby, the resist film 6 similar to the uneven shape of the roll transfer die 1 is formed on the wafer substrate 7 for LED chip elements.

Next, the resist film 6 is dry-etched by the RIE apparatus 8 that the resist film 6 was formed on the wafer substrate 7 for LED chip elements.

The etching chamber 40 of the RIE apparatus 8 is set in a vacuum state, controlled by the mass flow controller 46, and the active gas 53 is introduced into the etching chamber 40 at a pressure of 20-50 Pa.

The active gas 53 generates an active gas plasma indoors by plasma generation means such as high frequency by changing the flow rate mixing ratio of the H ₂ gas to the CF ₄ gas, thereby generating ions and radicals generated on the electrode by separating the active gas. etching by touching the placed wafer, but in this embodiment has a concentration of H ₂ gas for CF ₄ to 25%. This slows down the etching speed of the resist film.

As shown in Fig. 13, the thin portion of the resist film 6, that is, the curved portion 34 of the resist film, is etched at an early stage, and the processing surface of the wafer substrate 7 for LED chip elements is exposed.

Dry etching is further performed to reduce the etching rate of the acid portion 35 of the resist film shown in FIG. 13.

In addition, the curved portion 34 of the resist film has an uneven shape of the curved portion 34 of the resist film and the peak portion 35 of the resist film due to the exposure of the wafer substrate 7 for LED chip elements. It is formed on the wafer substrate 7 for LED chip elements.

This makes it possible to increase the aspect ratio, which is important for the diffraction grating structure 9. The present invention is also characterized in that a highly accurate resist film can be easily formed on the wafer substrate 7 for LED chip elements. As a result, a diffraction grating structure 9 is formed on the surface of the wafer substrate 7 for LED chip elements.

The diffraction grating structure 9 is formed on the wafer substrate 7 for the LED chip element, and as shown in FIG. 14, the linear light emitted from the LED chip element 26 increases the light energy due to the improved transmittance. In addition, in the conventional structure, the light emitted from the LED chip element 26 can be emitted from the LED chip element as the first-order diffracted light by the diffraction grating structure 9 even at an angle that cannot be transmitted in the LED chip element 26. Efficiency can be increased.

By forming the diffraction grating structure 9 of the LED chip element 26 on the GaP wafer substrate, the light output efficiency of 2.3 times as compared to the conventional one can be improved in the processing surface of the LED chip element 26.

It can also be applied to LED chip elements such as red lights such as Al Ga As.

1 is a view showing a roll transfer type of the present invention.

2A and 2B are process charts showing the production outline of the roll transfer die of the present invention.

Fig. 3 is a diagram showing a legend shape of a roll transfer type unevenness of the present invention.

4 is a view showing an apparatus for producing the uneven transfer film of the present invention.

5 is a cross-sectional view of the uneven transfer film laminate of the present invention.

It is sectional drawing of the laminated | multilayer film laminated body for RIE resist.

7 is a schematic diagram of an RIE apparatus.

8 is a schematic view of a RIE treatment process.

9 is a schematic diagram of a production RIE apparatus.

Fig. 10 shows the diffraction grating structure and the light path.

11 shows the concave-convex shape of the Si wafer substrate used in the embodiment of the present invention.

12 shows an example of master pole placement on a glass substrate of an embodiment of the present invention.

Fig. 13 shows the resist film shape and dry etching situation in the embodiment of the present invention.

14 shows a light emission situation according to an embodiment of the present invention.

≪ Description of reference numerals &

1 roll transfer type

2 plastic film

3 UV Curing Resin

4 uneven transfer film

5 photosensitive material

6 resist film

7 Wafer Board for LED Chip Device

8 RIE Device

9 Diffraction Grating Structure

10 Feed rate control roll

11a Gap Control Rolla

11b gap control roll b

12 UV lamp

13 winding speed control roll

14 winding device

15 gap plate

16 UV Curable Resin Feeder

17 UV Curing Resin Gap Roll

18 uneven UV curing resin layer

19 release film

20 laminated film for RIE resist

21 gap control roll

22 speed control roll

23 Mold Roll B

24 diffusion patterns

25 winding device

26 LED Chip Device

27 Si Wafer Substrate

28 Ag layer

29 master pole type

Unevenness behind 30 telephone poles

31 diamond bite planar processing machine

32 glass substrate

33 Master pole type Continuous batch type

34 Curve of Resist Film

35 Mountain of resist film

36 Ni precast

37 Ni pole layer

38 uneven shape of the roll transfer type

39 RIE vacuum chamber

40 Etching chamber

41 Transfer Seal

42 Load Room

43 Unload Room

44 Gate valve

44 vacuum robot

46 Mass flow controller

47 Turbo molecule pump

48 Conductance variable valve

49 Dry pump

50 rays

Concave-convex shape of 51 Si wafer substrate

52 Electroless Plating Method

53 Activated Gas

Claims (17)

delete delete delete delete (a) making a roll transfer mold in which a plurality of irregularities having a pitch of 300 nm or less are continuously formed; (b) transferring the concave-convex shape processed on the surface of the roll transfer mold to a plastic film to make a concave-convex transfer film; (c) applying a photosensitive material to the concave-convex surface of the concave-convex transfer film made in step (b), and then drying to form a layer to form a laminated film for resist; (d) laminating the laminated film for resist made in step (c) on the wafer substrate to be an LED chip element, irradiating UV from the outside of the laminated film for resist to cure the photosensitive material, and transferring the uneven projections Peeling the film from the cured photosensitive material to form a photosensitive material cured layer having a concave-convex structure on the wafer substrate to be the LED chip element; And (e) The uneven shape is etched to a depth of 500 nm or less on the wafer substrate to be the LED chip element on which the uneven photosensitive cured layer is formed, and after the etching, the unnecessary photosensitive material is removed to form the LED chip element. Forming a diffraction grating structure having a concave-convex pitch is 300nm or less. The method of manufacturing an LED chip element structure according to claim 5, wherein the uneven shape is any one selected from the group consisting of a cube, a cube and a cylinder. The method of claim 5, wherein in the step (b), the plastic film is made of any one material selected from the group consisting of polyolefin, polyvinyl chloride and biaxially stretched polyethylene terephthalate LED chip device structure manufacturing Way. 6. The LED of claim 5, wherein in step (c), the release film is coated on the surface of the photosensitive material and the release film is peeled off before laminating on the wafer substrate in step (d). Method for manufacturing a chip device structure. The method of claim 5, wherein the step (b) comprises applying the UV curable resin onto the plastic film and contacting the surface of the UV curable resin coated on the plastic film with the roll transfer type. And irradiating UV on the opposite side of the plastic film surface in contact with the plastic film to continuously transfer the opposite shape of the concave-convex shape to the plastic film surface to form an uneven transfer film. 10. The method according to claim 9, wherein the UV cured resin is coated with a roll coater, spin coater, spray, dipping coater, wire bar coater The method of manufacturing an LED chip device structure, characterized in that the coating using any one method selected from the group consisting of gravure coater (Gravure coater) coating and air knife coater (Air knife coater) coating. The UV curable resin according to claim 9, 50 parts by weight of UA1 (urethane oligomer (average molecular weight: 7,000)), 50 parts by weight of 4EG-A (tetra ethylene glycol diacrylate (bifunctional monomer)), and a photoinitiator (1-hydroxy cyclohexyl phenyl ketone) 2 parts by weight of the manufacturing method of the LED chip device structure characterized in that it comprises. 6. The method of claim 5, wherein in the step (e), the etching is performed using a reactive ion etching apparatus. 6. The method of claim 5, wherein in step (e), the unnecessary photosensitive material is removed by cleaning or ICP-RIE process using O ₂ gas. The method of manufacturing an LED chip device structure according to claim 5, wherein the photosensitive material is a polymer of negative shape or positive shape material. 15. The method of claim 14, wherein the polymer is a polymer A using styrene, methyl methacrylate, acrylate, acrylic acid, glycidyl methacrylate copolymer resin. The said photosensitive material is 70 weight part of polymer A, 30 weight part of pentaerythritol tetraacrylates (monomer), 2.2 weight part of Irgacure 369 (initiator), N, N-tetraethyl-4, 4 2.2 parts by weight of '-diaminobenzophenone (initiator), 492 parts by weight of propylene glycol monomethyl ether (solvent), 0.1 part by weight of p-methoxyphenol (polymerization inhibitor) and perfluoroalkyl alkoxylate (surfactant) Method for producing an LED chip device structure comprising 0.01 parts by weight. delete

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