LED chip wafer packaging alignment device and alignment method

Abstract

The present invention relates to an alignment device and an alignment method for LED chip wafer packaging. The device comprises a diaphragm carrier, a wafer stage, a microscope arranged above the wafer stage, a four-axis micrometer adjustment stage for adjusting the position of the wafer stage, a diaphragm pickup plate arranged above the diaphragm carrier, and a transverse movement mechanism for moving the diaphragm pickup plate to above the wafer stage; a plurality of vacuum suction ports are evenly arranged on the lower surface of the diaphragm pickup plate; the present invention can realize non-destructive picking of glass diaphragms through the diaphragm pickup plate, wherein high-precision alignment and bonding of wafers and glass diaphragms can be realized through the four-axis micrometer adjustment stage, and the bonding accuracy can reach within 2 microns, and the overall structure is simple, the volume is compact, the operation is convenient and quick, and the integration with the production line is high.

Description

Technical Field

[0001] The present invention relates to the technical field of high-precision wafer processing, and in particular to an alignment device and an alignment method for LED chip wafer packaging. Background Art

[0002] Wafer refers to the silicon wafer used in the production of silicon semiconductor integrated circuits. Because of its round shape, it is called a wafer. Various circuit component structures can be processed on the silicon wafer to become IC products with specific electrical functions. The original material of the wafer is silicon, and there is an inexhaustible supply of silicon dioxide on the surface of the earth's crust. Silicon dioxide ore is refined by an electric arc furnace, chlorinated with hydrochloric acid, and distilled to produce high-purity polysilicon with a purity of up to 99.999999999%. The wafer manufacturing plant then melts this polysilicon, plants seed crystals in the melt, and then slowly pulls it out to form a cylindrical single crystal silicon rod. Since the silicon rod is gradually generated from a seed crystal with a determined crystal plane orientation in the molten silicon raw material, this process is called "crystal growth". After the silicon rod is cut, rolled, sliced, chamfered, polished, laser engraved, and packaged, it becomes the basic raw material of the integrated circuit factory - silicon wafer, which is the "wafer".

[0003] In the LED industry, the wafer is also the core part of the LED. In fact, the main optoelectronic parameters of the LED, such as wavelength, brightness, and forward voltage, basically depend on the wafer material. The processing and production of LED related circuit components are all completed on the wafer, so wafer technology and equipment are the key to wafer manufacturing technology. The wafer needs to be cut before it becomes an LED chip, and before cutting, its surface needs to be encapsulated with a glass film. During the process, ultra-high precision alignment needs to be guaranteed. The current existing technology uses fully automatic equipment to achieve high precision, but this method will increase the purchase cost of the equipment, and the price of the equipment is tens of millions. Therefore, how to balance the equipment cost while ensuring production accuracy has become a major problem in the industry. To this end, we propose an LED chip wafer packaging alignment device and alignment method to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to provide an LED chip wafer package alignment device and alignment method in view of the deficiencies in the prior art, and the LED chip wafer package alignment device and alignment method can well solve the above-mentioned problems.

[0005] In order to achieve the above requirements, the technical solution adopted by the present invention to solve its technical problems is:

[0006] Provided is an LED chip wafer packaging alignment device, comprising a wafer stage, and a four-axis micrometer adjustment stage for adjusting the position of the wafer stage;

[0007] It also includes a film carrier, a film pickup plate arranged above the film carrier, and a lateral movement mechanism for the film pickup plate to be moved above the wafer table; a plurality of vacuum suction ports are evenly arranged on the lower surface of the film pickup plate;

[0008] Also included is a microscope arranged above the wafer stage.

[0009] The LED chip wafer package alignment device and alignment method described in the present invention further include a positioning mechanism for positioning the film pickup plate when the film pickup plate moves into position.

[0010] The LED chip wafer package alignment device and alignment method described in the present invention, wherein the positioning mechanism is provided with two and is respectively located at the initial end and the terminal end of the moving track of the film pickup plate, and the film pickup plate is located between the two positioning mechanisms.

[0011] The LED chip wafer package alignment device and alignment method described in the present invention, wherein the rear end of the diaphragm pickup plate is detachably provided with an airway adapter, the side wall of the diaphragm pickup plate is provided with multiple air supply ducts connected to the vacuum suction port, and the airway adapter is provided with an air inlet duct connected to the multiple air supply ducts.

[0012] In the LED chip wafer package alignment device and alignment method described in the present invention, the plurality of air supply channels are divided into two groups and are arranged in a crisscross pattern.

[0013] The LED chip wafer packaging alignment device and alignment method described in the present invention, wherein the film pickup plate is provided with an observation window.

[0014] The LED chip wafer packaging alignment device and alignment method described in the present invention, wherein the four-axis micrometer adjustment stage includes an X-axis fine-tuning stage, a Y-axis fine-tuning stage, a Z-axis fine-tuning stage and a rotation axis fine-tuning stage which are arranged in sequence from bottom to top.

[0015] The LED chip wafer package alignment device and alignment method described in the present invention, wherein the membrane carrier includes a carrying dish and a lifting mechanism for driving the carrying dish to rise and fall, and the upper surface edge of the carrying dish is recessed with an avoidance groove connected to its inner wall.

[0016] The LED chip wafer package alignment device and alignment method described in the present invention, wherein the microscope includes a microscope, a display for displaying an enlarged image of the microscope, and a moving mechanism for driving the microscope and the display to move horizontally.

[0017] A method for aligning an LED chip wafer package aligning device is also provided, the method comprising the following steps:

[0018] Step 1: Making a first marking position and a second marking position on the glass membrane and the wafer respectively, with the edge contours of the glass membrane and the wafer serving as the first marking position and the second marking position respectively;

[0019] Step 2: Move the film pickup plate away from the top of the film carrier through the transverse movement mechanism, and place the glass film on the film carrier, and reset the film pickup plate;

[0020] Step 3: Start the external negative pressure source and use the vacuum suction port to adsorb the glass membrane onto the membrane pickup plate;

[0021] Step 4: Move the membrane pickup plate with the glass membrane sucked on it to just above the wafer table through the lateral movement mechanism, adjust the relative position of the wafer table and the membrane pickup plate through the four-axis micrometer adjustment table, and make the projections of the first mark position and the second mark position overlap, wherein the lateral allowable error of the overlap is between 1-2 microns.

[0022] The beneficial effects of the present invention are as follows: the present invention can realize non-destructive picking up of glass membranes through the membrane pickup plate, wherein the high-precision alignment and bonding of the wafer and the glass membrane can be realized through the four-axis micrometer adjustment table, and the bonding accuracy can reach within 2 microns, and the overall structure is simple, the volume is small, the operation is convenient and fast, and the integration with the production line is high. Compared with the implementation method using fully automated equipment, the cost is greatly reduced, and the adaptability to different processing occasions is stronger, so that the cost and production quality are balanced. Consideration. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work:

[0024] Figure 1 It is an overall front view of the LED chip wafer packaging alignment device of the present invention.

[0025] Figure 2 It is an overall right side view of the LED chip wafer packaging alignment device of the present invention.

[0026] Figure 3 It is a structural diagram of a membrane carrier of an LED chip wafer packaging alignment device of the present invention.

[0027] Figure 4 The present invention is a bottom view of a film pickup plate of an LED chip wafer packaging alignment device.

[0028] Figure 5It is a top view of the film pick-up plate of the LED chip wafer packaging alignment device of the present invention.

[0029] Figure 6 It is an exploded view of the diaphragm pickup plate and the airway adapter of the LED chip wafer packaging alignment device of the present invention.

[0030] Figure 7 Position relationship diagram of the four-axis micrometer adjustment stage and the wafer stage of the LED chip wafer packaging alignment device of the present invention.

[0031] Figure 8 It is a flow chart of the steps of the alignment method of the LED chip wafer packaging alignment device of the present invention. DETAILED DESCRIPTION

[0032] The terms "first", "second", "third" and "fourth" etc. in the specification and claims of the present invention and the drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices.

[0033] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0034] "Multiple" means two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the related objects are in an "or" relationship.

[0035] Moreover, the terms "up, down, left, right, upper end, lower end, longitudinal" and the like indicating directions are all based on the posture and position of the device or equipment described in this solution during normal use.

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the following will be described clearly and completely in combination with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are partial embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention.

[0037] The LED chip wafer packaging alignment device of the preferred embodiment of the present invention is as follows: Figure 1-7 As shown, it includes a wafer table 1 for placing a wafer 100, and a four-axis micrometer adjustment table 2 for adjusting the spatial position of the wafer table 1;

[0038] The device further includes a membrane stage 3 for placing a glass membrane 200, a membrane pickup plate 4 disposed above the membrane stage 3, and a lateral movement mechanism 5 for moving the membrane pickup plate 4 to the top of the wafer table 1; specifically, the lateral movement mechanism 5 is a guide rail module, and in addition, an electrically driven screw motor module or a linear motor module may also be used. A plurality of vacuum suction ports 6 are evenly arranged on the lower surface of the membrane pickup plate 4 to suck up the glass membrane;

[0039] The device also includes a microscope 7 disposed above the wafer stage 1 , so that an operator can adjust the position of the wafer in coordination with the four-axis micrometer adjustment stage 2 .

[0040] In addition, in order to ensure the reasonable integration of the various components of the device, the microscope 7, the transverse movement mechanism 5 and the diaphragm carrier 3 are all arranged on the first mounting plate 8, and a second mounting plate 9 fixed thereto is provided below the first mounting plate 8. The four-axis micrometer adjustment table 2 and the diaphragm carrier 3 are both arranged on the second mounting plate 9, and a window 10 for exposing the four-axis micrometer adjustment table 2 is provided on the first mounting plate 8. A bracket is formed by the first mounting plate 8 and the second mounting plate 9, which can be easily moved and assembled.

[0041] The present invention can realize non-destructive picking up of glass membranes through the membrane pickup plate 4, wherein the high-precision alignment and bonding of the wafer and the glass membrane can be realized through the four-axis micrometer adjustment table 2, and the bonding accuracy can reach within 2 microns, and the overall structure is simple, the volume is small, the operation is convenient and fast, and the degree of integration with the production line is high. Compared with the implementation method using fully automated equipment, the cost is greatly reduced, and the adaptability to different processing occasions is stronger, so that the cost and production quality are well balanced.

[0042] Preferably, the device also includes a positioning mechanism 11 for positioning the diaphragm pickup disk 4 when it moves into position. Specifically, the positioning mechanism 11 is provided with two and is respectively located at the initial end and the terminal end of the moving trajectory of the diaphragm pickup disk 4, wherein the initial end and the terminal end are respectively located on the side opposite to the diaphragm carrier 3 and the wafer table 1, and the diaphragm pickup disk 4 is located between the two positioning mechanisms 11 to limit its stroke and prevent the diaphragm pickup disk 4 from accidentally moving. In practice, the positioning mechanism 11 is a magnetic stop member, and a magnet 12 is further provided on the diaphragm pickup disk 4 corresponding to the magnetic stop member, so that the positioning mechanism 11 and the magnet 12 are attracted and fixed to each other. Compared with other positioning methods such as snap positioning or latch positioning, the use of magnetic positioning can not only avoid the influence of the idle stroke difference caused by the processing accuracy of the equipment, but also facilitate the operator to easily separate the diaphragm pickup disk 4 from the positioning mechanism 11, without the operator having to perform too many unlocking actions on the diaphragm pickup disk 4, thereby greatly omitting unnecessary process steps and ensuring production efficiency.

[0043] Preferably, the rear end of the diaphragm picking plate 4 is detachably provided with an airway adapter 13, and the front end is provided with a handle 14 for easy manual pushing, the side wall of the diaphragm picking plate 4 is provided with a plurality of air supply ducts 15 connected to the vacuum suction port 6, the airway adapter 13 is provided with an air inlet duct 16 connected to the plurality of air supply ducts 15, and a suction nozzle 17 is provided at the inlet end of the air inlet duct 16. The provision of the airway adapter 13 can reduce the number of vacuum air pipes, simplifying the assembly process while reducing the equipment failure rate.

[0044] Preferably, the plurality of air supply channels 15 are divided into two groups and arranged in a crisscross pattern to ensure that the force at each position of the glass membrane is balanced when the glass membrane is sucked.

[0045] Preferably, the diaphragm pickup plate 4 is provided with a plurality of observation windows 18 to facilitate observation of the edge position of the glass diaphragm. Furthermore, the plurality of observation windows 18 are opened corresponding to the plurality of air supply passages 15 to form a hollow tic-tac-toe structure on the diaphragm pickup plate 4, thereby reducing weight and material.

[0046] Preferably, the four-axis micrometer adjustment stage 2 includes an X-axis fine-tuning stage 201, a Y-axis fine-tuning stage 202, a Z-axis fine-tuning stage 203 and a rotating axis fine-tuning stage 204, which are arranged in sequence from bottom to top, and the adjustment accuracy of the four is at the micrometer level or above, so as to achieve high-precision movement of the X\Y\Z axes, and horizontal rotation, wherein the horizontal rotation specifically includes initial adjustment and fine adjustment, the initial adjustment can achieve a 360-degree rotation, and the fine adjustment can achieve a minimum angle adjustment of 10 degrees.

[0047] Preferably, the diaphragm carrier 3 includes a carrying dish 301 and a lifting mechanism 302 for driving the carrying dish 301 to rise and fall. Specifically, the carrying dish 301 is arranged above the first mounting plate 8, and the lifting mechanism 302 is a cylinder and is arranged on the second mounting plate 9. The movable rod of the cylinder passes through the first mounting plate 8 and is connected to the carrying dish 301. The upper surface edge of the carrying dish 301 is recessed with an avoidance groove 19 connected to its inner wall, so that people can hold the glass diaphragm by hand until it is completely placed in the carrying dish 301 to avoid damaging the glass diaphragm.

[0048] Preferably, the microscope 7 includes a microscope 71, a display 72 for displaying an enlarged image of the microscope 71, and a moving mechanism 73 for driving the microscope 71 and the display 72 to move horizontally; specifically, the moving mechanism 73 is an XY-axis slide rail assembly to adjust the position of the microscope 7.

[0049] The wafer alignment method of the LED chip wafer packaging alignment device of the preferred embodiment of the present invention is as follows: Figure 8 As shown, the method comprises the following steps:

[0050] Step S10: making a first marking position and a second marking position on the glass film and the wafer respectively, with the edge contours of the glass film and the wafer serving as the first marking position and the second marking position respectively;

[0051] Step 2 S20: Move the film pickup plate 4 away from the top of the film carrier 3 through the lateral movement mechanism 5, and place the glass film on the film carrier 3, and the film pickup plate 4 is reset;

[0052] Step 3 S30: Start the external negative pressure source and cooperate with the vacuum suction port 6 to adsorb the glass membrane onto the membrane pickup plate 4;

[0053] Step 4 S40: Move the membrane pickup plate 4 with the glass membrane sucked thereon to the top of the wafer table 1 through the transverse movement mechanism 5, and adjust the XY axis relative position of the wafer table 1 and the membrane pickup plate 4 through the four-axis micrometer adjustment table 2 to make the projections of the first mark position and the second mark position coincide with each other, wherein the coincidence of the first mark position and the second mark position is displayed through the display 72, and the lateral allowable error of the coincidence is between 1-2 microns, and further, the wafer table 1 is lifted up through the Z-axis fine-tuning table 203 to adhere the wafer to the lower surface of the glass membrane, thereby completing the pre-packaging of the wafer.

[0054] In addition, when observing the alignment of the first marking position and the second marking position, at least two different positions of the first marking position and the second marking position are observed.

[0055] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. An LED chip wafer packaging alignment device, characterized in that: It includes a wafer stage, and a four-axis micrometer adjustment stage for adjusting the position of the wafer stage; It also includes a film carrier, a film pickup plate arranged above the film carrier, and a lateral movement mechanism for the film pickup plate to be moved above the wafer table; a plurality of vacuum suction ports are evenly arranged on the lower surface of the film pickup plate; Also included is a microscope disposed above the wafer stage; It also includes a positioning mechanism for positioning the film pickup plate when it moves into position, wherein two positioning mechanisms are provided and are respectively located at the initial end and the terminal end of the moving track of the film pickup plate, and the film pickup plate is located between the two positioning mechanisms; The rear end of the diaphragm pickup plate is detachably provided with an airway adapter, a plurality of air supply channels connected to the vacuum suction port are provided on the side wall of the diaphragm pickup plate, and an air inlet channel connected to the plurality of air supply channels is provided on the airway adapter; the plurality of air supply channels are divided into two groups and are arranged crisscross with each other; The membrane carrier comprises a carrier plate and a lifting mechanism for driving the carrier plate to lift and lower. The upper surface edge of the carrier plate is concavely formed with an avoidance groove communicating with the inner wall thereof.

2. The LED chip wafer packaging alignment device according to claim 1, characterized in that: The film picking plate is provided with an observation window.

3. The LED chip wafer packaging alignment device according to claim 1, characterized in that: The four-axis micrometer adjustment platform includes an X-axis fine-tuning platform, a Y-axis fine-tuning platform, a Z-axis fine-tuning platform and a rotating axis fine-tuning platform which are arranged in sequence from bottom to top.

4. The LED chip wafer packaging alignment device according to claim 1, characterized in that: The microscope includes a microscope, a display for displaying an enlarged image of the microscope, and a moving mechanism for driving the microscope and the display to move horizontally.

5. A wafer alignment method for an LED chip wafer packaging alignment device, according to the LED chip wafer packaging alignment device according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: Step 1: Making a first marking position and a second marking position on the glass membrane and the wafer respectively, with the edge contours of the glass membrane and the wafer serving as the first marking position and the second marking position respectively; Step 2: Move the film pickup plate away from the top of the film carrier through the transverse movement mechanism, and place the glass film on the film carrier, and reset the film pickup plate; Step 3: Start the external negative pressure source and use the vacuum suction port to adsorb the glass membrane onto the membrane pickup plate; Step 4: Move the membrane pickup plate with the glass membrane sucked on it to just above the wafer table through the lateral movement mechanism, adjust the relative position of the wafer table and the membrane pickup plate through the four-axis micrometer adjustment table, and make the projections of the first mark position and the second mark position overlap, wherein the lateral allowable error of the overlap is between 1-2 microns.

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