LED device and manufacturing method thereof

Abstract

The invention relates to the technical field of LED preparation, in particular to an LED device and a manufacturing method thereof. The manufacturing method comprises the steps that a first conducting layer and a second conducting layer which are communicated with each other are attached to the two surfaces of a second substrate, a first substrate provided with an LED chip in an attached mode is attached to the first conducting layer of the second substrate, and the LED chip is electrically connected with the first conducting layer; etching the first conductive layer to form a plurality of conductive salient points, wherein each conductive salient point is conducted with the LED chip and the second conductive layer; and packaging the first substrate and the second substrate, and carrying out circuit forming processing on one side of the second conductive layer of the second substrate. The manufacturing method has no requirement for the transfer precision of the LED chip, the precision requirement for transfer equipment and line etching equipment is low, and the problems of high precision requirement, low yield and high cost of mass transfer caused by LED miniaturization are solved.

Description

Technical Field

[0001] The invention relates to the technical field of LED preparation, and in particular to an LED device and a preparation method thereof. Background Art

[0002] Light-emitting diode (LED) light sources have the advantages of high brightness, high contrast, high color gamut, long life, strong anti-collision ability, and high reliability. With the rapid development of LED technology, the brightness and life of LEDs have been greatly improved, making the application of LEDs more and more extensive. They are widely used in high-definition display fields such as high-end rental, car display, theater live broadcast, virtual shooting, etc. However, due to the limitations of manufacturing technology, LED devices have the problems of high cost and low yield.

[0003] Currently, one of the major problems restricting the cost, yield and miniaturization of LED devices is the mass transfer method of LED chips. The mass transfer technology is to transfer LED chips to a specific driver substrate. Through this technology, multiple small LED chips can be correctly and efficiently transferred to a large carrier, thereby producing a display screen with higher resolution and higher brightness.

[0004] In the related technologies, mass transfer methods include: electrostatic force adsorption transfer, fluid assembly transfer, elastic mold transfer, laser selective release transfer, etc. These methods are either not efficient enough or have low transfer accuracy. Too low efficiency will lead to insufficient output, while low transfer accuracy will cause a decrease in yield. Therefore, it is difficult for traditional production methods to take into account both yield and output, and there are certain difficulties in practical application. Therefore, how to achieve low-cost and efficient mass transfer of LED devices has become a difficult problem that practitioners need to solve urgently. Summary of the invention

[0005] In the related technology, the manufacturing method of LED devices is limited by the transfer accuracy, and it is difficult to take into account the yield rate and output requirements of LED device manufacturing.

[0006] In a first aspect, an embodiment of the present application provides a method for manufacturing an LED device, which includes: A first conductive layer and a second conductive layer that are conductive to each other are attached to two surfaces of the second substrate, the first substrate with the LED chip attached is attached to the first conductive layer of the second substrate, and the LED chip is electrically connected to the first conductive layer; Etching the first conductive layer to form a plurality of conductive bumps, each of the conductive bumps being electrically connected to the LED chip and the second conductive layer; The first substrate and the second substrate are packaged, and a circuit forming process is performed on one side of the second conductive layer of the second substrate.

[0007] In combination with the first aspect, in one embodiment, the first conductive layer and the second conductive layer that are electrically connected to each other are affixed on the two surfaces of the second substrate, including: opening at least one through hole on the second substrate, and filling conductive material on both side surfaces and the through hole of the second substrate, so as to form the first conductive layer and the second conductive layer on the two side surfaces of the second substrate, and at the same time, form a third conductive part that is electrically connected to the first conductive layer and the second conductive layer in the through hole of the second substrate.

[0008] In combination with the first aspect, in one implementation, filling both side surfaces and through holes of the original substrate with conductive material includes: electroplating conductive metal on both side surfaces of the second substrate.

[0009] In combination with the first aspect, in one embodiment, electroplating conductive metal on both side surfaces of the second substrate includes: Conductive metal is electroplated on the surface of the second substrate to form the first conductive layer, and the height of the first conductive layer in the thickness direction of the second substrate is smaller than the height of the pins of the LED chip in the thickness direction of the first substrate.

[0010] In combination with the first aspect, in one implementation, both the first substrate and the second substrate are made of glass substrates.

[0011] In combination with the first aspect, in one implementation, packaging the first substrate and the second substrate includes: filling a packaging colloid between the first substrate and the second substrate, wherein a thermal conductive material is mixed in the packaging colloid.

[0012] In combination with the first aspect, in one implementation, the thermally conductive material includes boron nitride powder.

[0013] In combination with the first aspect, in one embodiment, laminating the first substrate with the LED chip on it onto the second substrate comprises: The first substrate is laminated to the first conductive layer of the second substrate, and the pins of the LED chip are connected to the first conductive layer by soldering.

[0014] In combination with the first aspect, in one embodiment, the circuit forming process of the second conductive layer of the second substrate includes: using an exposure process to process the second conductive layer into conductive pins In a second aspect, an embodiment of the present application provides an LED device, comprising: an LED device manufactured using any of the above-mentioned methods for manufacturing an LED device.

[0015] The beneficial effects brought by the technical solution provided by the embodiment of the present application include at least: The present application sets a first conductive layer and a second conductive layer that are mutually conductive on the large surfaces on both sides of the substrate, uses the large area conductive layer to electrically connect with the LED chip, and then etches away the redundant conductive layer. Since the LED chip pins can be directly electrically connected to the conductive layer, there is no requirement for the transfer accuracy of the LED chip, and the accuracy requirements for the transfer equipment and the circuit etching equipment are low, thus solving the problems of high precision requirements, low yield, and high cost of mass transfer caused by LED miniaturization. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A cross-sectional view of the LED device in the embodiment of the present application from the main viewing angle; Figure 2 A bottom view of the LED device in the embodiment of the present application; Figure 3 A cross-sectional view of the first substrate in the embodiment of the present application from a main viewing angle; Figure 4 A cross-sectional view of the LED device in the embodiment of the present application at the main viewing angle in step S3; Figure 5 This is a cross-sectional view of the main viewing angle of the LED device in step S4 in the embodiment of the present application. Figure 6 A partial cross-sectional view of the LED device in step S4 in the embodiment of the present application; Figure 7 A cross-sectional view of the LED device at the main viewing angle in step S5 in the embodiment of the present application; Figure 8 A cross-sectional view of the LED device in the embodiment of the present application at the main viewing angle in step S6a; Fig. 9 A cross-sectional view of the LED device at the main viewing angle in step S6b in the embodiment of the present application; Fig.10 It is a cross-sectional view of the LED device in the embodiment of the present application at the main viewing angle in step S6c.

[0018] In the figure: 1. LED chip; 11. pin; 12. solder paste; 2. first substrate; 3. second substrate; 31. through hole; 4. first conductive layer; 41. conductive bump; 5. second conductive layer; 51. conductive pin; 6. third conductive part; 7. packaging colloid; 8. photosensitive dry film; 9. insulating ink. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0020] In the related technology, the manufacturing method of LED devices is limited by the transfer accuracy, and it is difficult to take into account the yield rate and output requirements of LED device manufacturing.

[0021] In a first aspect, the present application provides a method for manufacturing an LED device, which comprises the following steps: Step S1: transferring the LED chip 1 to the first substrate 2 by mass transfer technology.

[0022] Preferably, the first substrate 2 can be a glass substrate.

[0023] It is worth mentioning that using a glass substrate as a base can greatly improve the flatness of LED devices, which is beneficial to improving the accuracy of mass transfer and the production of micro LED devices.

[0024] Specifically, transparent glue can be applied on the surface of the first substrate 2 to tightly adhere the transferred LED chip 1 to the first substrate 2. Figure 3 As shown, solder paste 12 is attached to the pins 11 of the LED chip 1 to form the LED chip 1 with tin electrodes.

[0025] It can be understood that the solder paste 12 is used to connect the LED chip 1 to the conductive layer through a soldering process in a subsequent step.

[0026] Step S2, a first conductive layer 4 and a second conductive layer 5 which are conductive to each other are attached to two surfaces of the second substrate 3.

[0027] It is worth noting that the first conductive layer 4 and the second conductive layer 5 located on the upper and lower surfaces of the second substrate 3 are connected to each other. The first conductive layer 4 is used to electrically connect with the LED chip 1. Since the first conductive layer 4 has a large area, it is relatively easy to electrically connect the pins 11 of the LED chip 1 with the first conductive layer 4. Therefore, the transfer accuracy requirement for the LED chip 1 is relatively low.

[0028] The above step S2 specifically includes: Step S2a: opening at least one through hole 31 on the second substrate 3 .

[0029] Preferably, the second substrate 3 may be a glass substrate.

[0030] It is worth mentioning that using a glass substrate as a base can greatly improve the flatness of LED devices, which is beneficial to improving the accuracy of mass transfer and the production of micro LED devices.

[0031] Step S2b, filling conductive material on both side surfaces of the second substrate 3 and in the through hole 31 to form a first conductive layer 4 and a second conductive layer 5 on both side surfaces of the second substrate 3, and forming a third conductive part 6 in the through hole 31 of the second substrate 3 that is conductive to the first conductive layer 4 and the second conductive layer 5.

[0032] It can be understood that, in the above embodiment, the first conductive layer 4 and the second conductive layer 5 are connected by the conductive material in the through hole 31. Furthermore, by increasing the number of through holes 31 in the second substrate 3, the through holes 31 are densely arranged on the second substrate 3, thereby increasing the number of conductive paths between the first conductive layer 4 and the second conductive layer 5, so as to reduce the precision requirement for etching the second conductive layer 5 in the subsequent steps.

[0033] In a preferred implementation of the above step S2b, Figure 4 As shown, by electroplating conductive metal on both side surfaces of the second substrate 3, a first conductive layer 4 and a second conductive layer 5 are formed on both side surfaces of the second substrate 3, and a third conductive portion 6 is formed in the through hole 31 of the second substrate 3.

[0034] It is understandable that after drilling the second substrate 3 to form the through hole 31, a metal layer is electroplated on the upper and lower surfaces of the second substrate 3 to form the first conductive layer 4 and the second conductive layer 5. In this process, the through hole 31 in the second substrate 3 is also plated with metal to form the third conductive part 6. Further, the third conductive part 6, the first conductive layer 4 and the second conductive layer 5 are all made of conductive metal materials, which can provide the function of electrical connection for the LED device on the one hand, and on the other hand, since the thermal conductivity of general metals can reach more than 400 W / m·K, the thermal conductivity of metal materials can be used to improve the all-round heat dissipation capacity of the LED device.

[0035] In the above-mentioned process of electroplating a metal layer on the surface of the second substrate 3, some preferred implementations include: electroplating a conductive metal on the surface of the second substrate 3 to form the first conductive layer 4, and making the height of the first conductive layer 4 in the thickness direction of the second substrate 3 smaller than the height of the pins 11 of the LED chip 1 in the thickness direction of the first substrate 2.

[0036] It is understandable that if Figure 6 As shown, the higher the height H1 of the pin 11 is, the larger the gap between the bottom of the LED chip 1 and the first conductive layer 4 is, which is beneficial for the etching solution to flow into the bottom of the LED chip 1 to etch away the excess metal on the first conductive layer 4 in the subsequent etching process.

[0037] Step S3 , attaching the first substrate 2 with the LED chip 1 attached thereto onto the first conductive layer 4 of the second substrate 3 , and electrically connecting the LED chip 1 to the first conductive layer 4 .

[0038] Specifically, after the LED chip 1 is attached to the first conductive layer 4, Figure 4 As shown, the solder paste on the pins 11 of the LED chip 1 is melted by heating to melt the solder, thereby tightly connecting the LED chip 1 to the first conductive layer 4 .

[0039] It is worth noting that the solder paste welding process is mature and has low cost. Further, the process of connecting the LED chip 1 and the first conductive layer 4 in step S3 of the present application is not limited to the above specific implementation, and other feasible connection methods (such as laser welding) can be used as needed.

[0040] Step S4 , etching the first conductive layer 4 to form a plurality of conductive bumps 41 , each of the conductive bumps 41 being electrically connected to the LED chip 1 and the second conductive layer 5 .

[0041] Specifically, the first conductive layer 4 is placed in an etching solution, and only the portion of the first conductive layer 4 connected to the solder paste 12 is retained during the etching process, and the rest of the first conductive layer 4 is completely etched away. Figure 5 As shown, the remaining portion of the first conductive layer 4 is the conductive bump 41 connected to the solder paste 12 .

[0042] It is worth noting that all the excess metal material of the first conductive layer 4 needs to be etched away. If the etching is not thorough, it will cause a short circuit between the positive and negative electrodes, thereby affecting the lighting of the RGB chip. Further, as mentioned above, since a plurality of tiny through holes 31 are provided in the second substrate 3, the through holes 31 are densely arranged, thereby increasing the number of conductive paths between the first conductive layer 4 and the second conductive layer 5, so as to ensure that even if the conductive bumps 41 formed on the first conductive layer 4 after etching can still be conductively connected to the second conductive layer 5 through the third conductive portion 6 in some of the through holes 31.

[0043] Step S5: packaging the first substrate 2 and the second substrate 3.

[0044] Specifically, Figure 7 As shown, a packaging colloid 7 is filled between the first substrate 2 and the second substrate 3 to complete the packaging. A transparent colloid or a black colloid can be used according to actual needs.

[0045] It is understandable that the packaging process is to protect the LED chip 1 from the influence of the external environment (such as humidity, dust and chemicals, etc.).

[0046] In some preferred embodiments, a thermal conductive material is mixed into the packaging colloid 7. The thermal conductive material may include boron nitride (BN) powder.

[0047] It is worth noting that in traditional technologies, LED packaging devices are all encapsulated by insulating colloids and various resins, and the thermal conductivity of insulating colloids and resins is extremely low, generally less than 1W / m·K. This results in extremely poor heat dissipation capacity of LED devices, and excessive heat will affect the color temperature and brightness of the LED chip 1, causing light decay and affecting the final display effect. In the above preferred embodiment of the present application, the thermal conductivity of boron nitride powder can reach 200-400 W / m·K, which helps the all-round heat dissipation capacity of LED devices.

[0048] Step S6, performing circuit forming processing on one side of the second conductive layer 5 of the second substrate 3.

[0049] In a specific implementation manner, the second conductive layer 5 is processed into the conductive pin 51 by using an exposure process, and the specific processing method includes: Step S6a, Figure 8 As shown, a layer of photosensitive dry film 8 is pre-coated on the surface of the second conductive layer 5, and the circuit diagram is accurately projected onto the copper clad layer of the circuit board using LDI (laser direct imaging) technology.

[0050] It is understandable that after being irradiated by strong ultraviolet light, some areas of the photosensitive dry film 8 are initially cured, and this process determines the final circuit shape.

[0051] Step S6b, after the photosensitive dry film 8 is cured, the conductive metal in the area of ​​the second conductive layer 5 not covered by the photosensitive dry film 8 is removed by development, and the conductive metal in the area of ​​the second conductive layer 5 not covered by the photosensitive dry film 8 is obtained. Fig. 9 The conductive pin 51 is shown.

[0052] Step S6c: Fig.10 As shown, a layer of insulating ink 9 is sprayed on the remaining photosensitive dry film 8 and the surface of the second substrate 3 .

[0053] Preferably, the thickness of the sprayed insulating ink 9 should be smaller than the thickness of the conductive pins 51 to facilitate the subsequent removal of the remaining photosensitive dry film 8 .

[0054] Step S6d: Use an alkaline agent to remove the photosensitive dry film 8, and obtain Figure 2 LED device shown.

[0055] It is worth mentioning that circuit exposure technology can achieve high-precision circuit design with an accuracy of up to 0.01 mm, which is suitable for miniaturization and high-density circuit design. In addition, the exposure time is short, which is suitable for large-scale production and can significantly improve production efficiency. Compared with traditional manufacturing methods, circuit exposure technology has lower costs and economic benefits.

[0056] In a second aspect, the present application provides an LED device manufactured using any one of the above-mentioned manufacturing methods.

[0057] In some specific embodiments, Figure 1 As shown, the LED device comprises: a first substrate 2 and a second substrate 3; wherein, A first substrate 2 is provided with an LED chip 1 thereon; a second substrate 3 is provided in contact with the first substrate 2, a surface of one side of the second substrate 3 is provided with a plurality of conductive bumps 41, and a surface of the other side of the second substrate 3 is provided with conductive pins 51, the conductive bumps 41 are electrically connected to the LED chip 1, and the conductive pins 51 are conductively connected to the conductive bumps 41.

[0058] Furthermore, at least one through hole 31 is formed on the second substrate 3, and the through hole 31 is filled with a third conductive portion 6 that is conductively connected to the conductive bump 41 and the conductive pin 51. Preferably, a plurality of densely arranged through holes 31 are formed on the second substrate 3.

[0059] It is worth noting that, in the above embodiment, the first conductive layer 4 and the second conductive layer 5 are connected by the conductive material in the through hole 31. Furthermore, by increasing the number of through holes 31 in the second substrate 3, the through holes 31 are densely arranged on the second substrate 3, thereby increasing the number of conductive paths between the first conductive layer 4 and the second conductive layer 5, thereby reducing the precision requirement for etching the second conductive layer 5 in the manufacturing process, and improving the production efficiency of the LED device.

[0060] In some preferred implementations, the conductive bumps 41 , the conductive pins 51 and the third conductive portion 6 are all made of conductive metal.

[0061] It is worth noting that the third conductive part 6, the first conductive layer 4 and the second conductive layer 5 are all made of conductive metal materials, which can provide electrical connection for the LED device on the one hand, and on the other hand, since the thermal conductivity of general metals can reach more than 400 W / m·K, the thermal conductivity of metal materials can be used to improve the all-round heat dissipation capacity of the LED device.

[0062] Furthermore, a packaging colloid 7 is filled between the first substrate 2 and the second substrate 3, and a heat-conducting material is mixed in the packaging colloid 7. The heat-conducting material may include boron nitride (BN) powder.

[0063] It is worth noting that in traditional technologies, LED packaging devices are all encapsulated by insulating colloids and various resins, and the thermal conductivity of insulating colloids and resins is extremely low, generally less than 1W / m·K. This results in extremely poor heat dissipation capacity of LED devices, and excessive heat will affect the color temperature and brightness of the LED chip 1, causing light decay and affecting the final display effect. In the above preferred embodiment of the present application, the thermal conductivity of boron nitride powder can reach 200-400 W / m·K, which helps the all-round heat dissipation capacity of LED devices.

[0064] In summary, the LED device manufacturing method of the present application is to set a first conductive layer and a second conductive layer that are connected to each other on the large surfaces on both sides of the substrate, and then use the large area of ​​the conductive layer to electrically connect with the LED chip, and then etch away the excess conductive layer. Since the LED chip pins can be directly electrically connected to the conductive layer, there is no requirement for the transfer accuracy of the LED chip, and the transfer process has low requirements for the accuracy of the transfer equipment and the circuit etching equipment, which solves the problems of high precision requirements, low yield and high cost of massive transfer caused by the miniaturization of LEDs. Furthermore, the present application sets a plurality of densely arranged through holes in the substrate, and the surface of the through holes is plated with conductive metal. By connecting the upper and lower surfaces by through holes, the etching accuracy requirements for the device pins are not high when the LED device is manufactured, which is also conducive to the low-cost and high-efficiency manufacturing of conductive pins. Finally, the LED device can enhance the all-round heat dissipation capacity of the LED device by mixing the insulating colloid of the high thermal conductivity powder and the metal in the through hole of the substrate.

[0065] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0066] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0067] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for manufacturing an LED device, characterized in that: include: A first conductive layer (4) and a second conductive layer (5) which are electrically connected to each other are attached to two surfaces of a second substrate (3); the first substrate (2) on which an LED chip (1) is attached is attached to the first conductive layer (4) of the second substrate (3); and the LED chip (1) is electrically connected to the first conductive layer (4); Etching the first conductive layer (4) to form a plurality of conductive bumps (41), each of the conductive bumps (41) being electrically connected to the LED chip (1) and the second conductive layer (5); The first substrate (2) and the second substrate (3) are packaged, and a circuit forming process is performed on one side of the second conductive layer (5) of the second substrate (3).

2. The method for manufacturing an LED device according to claim 1, characterized in that: The first conductive layer (4) and the second conductive layer (5) which are conductive to each other are attached to the two surfaces of the second substrate (3), comprising: at least one through hole (31) is opened on the second substrate (3), and conductive material is filled on both side surfaces of the second substrate (3) and in the through hole (31), so that the first conductive layer (4) and the second conductive layer (5) are formed on the two side surfaces of the second substrate (3), and a third conductive part (6) which is conductive to the first conductive layer (4) and the second conductive layer (5) is formed in the through hole (31) of the second substrate (3).

3. The method for manufacturing an LED device according to claim 2, characterized in that: The step of filling the conductive material on both side surfaces of the original substrate and in the through hole (31) comprises: electroplating the conductive metal on both side surfaces of the second substrate (3).

4. The method for manufacturing an LED device according to claim 3, characterized in that: The electroplating of conductive metal on both sides of the second substrate (3) comprises: Conductive metal is electroplated on the surface of the second substrate (3) to form the first conductive layer (4), and the height of the first conductive layer (4) in the thickness direction of the second substrate (3) is smaller than the height of the pins (11) of the LED chip (1) in the thickness direction of the first substrate (2).

5. The method for manufacturing an LED device according to claim 1, wherein: The first substrate (2) and the second substrate (3) are both made of glass substrates.

6. The method for manufacturing an LED device according to claim 1, characterized in that: The packaging of the first substrate (2) and the second substrate (3) comprises: filling a packaging colloid (7) between the first substrate (2) and the second substrate (3), wherein a heat-conducting material is mixed in the packaging colloid (7).

7. The method for manufacturing an LED device according to claim 6, characterized in that: The thermally conductive material includes boron nitride powder.

8. The method for manufacturing an LED device according to claim 1, wherein: The step of laminating the first substrate (2) having the LED chip (1) affixed thereto on the second substrate (3) comprises: The first substrate (2) is laminated to the first conductive layer (4) of the second substrate (3), and the pins (11) of the LED chip (1) are connected to the first conductive layer (4) by soldering.

9. The method for manufacturing an LED device according to claim 1, wherein: The circuit forming process of the second conductive layer (5) of the second substrate (3) comprises: using an exposure process to process the second conductive layer (5) into conductive pins (51).

10. An LED device, characterized in that: include: An LED device manufactured using the method for manufacturing an LED device as claimed in any one of claims 1 to 9.

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