Seed crystal bonding apparatus and method

Abstract

A seed crystal bonding device and method, wherein the seed crystal bonding device comprises a base for carrying the seed crystal, a limiting device arranged on the base and used for limiting the position of the seed crystal on the base, an adhesive processing device comprising a processing bin and a glue applying unit, the processing bin being connected with the glue applying unit, the processing bin being used for heat-activating the adhesive, and the glue applying unit being used for applying the heat-activated adhesive to the base, and a pressing device, a movable end of the pressing device being adapted to move in a vertical direction to press the seed crystal to the base. The seed crystal bonding device and method provided by the embodiments of the present application can improve the bonding strength and quality between the seed crystal and the base.

Description

Technical Field

[0001] This invention relates to the field of crystal growth technology, and in particular to a seed crystal bonding device and method. Background Technology

[0002] In the field of crystal growth technology, it is usually necessary to bond the seed crystal and the substrate together to provide stable and precise support for the subsequent crystal growth and ensure that the single crystal grows in an orderly manner along the crystal orientation of the seed crystal. Therefore, the bonding quality between the seed crystal and the substrate directly affects the growth quality of the crystal.

[0003] However, current seed crystal and substrate bonding technologies still suffer from problems such as inaccurate seed crystal positioning, residual air bubbles after bonding, and low bonding quality. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a seed crystal bonding device and method, which is beneficial to improving the bonding strength and bonding quality between the seed crystal and the substrate.

[0005] To address the aforementioned technical problems, this invention provides a seed crystal bonding device, comprising: a base for supporting the seed crystal; a limiting device disposed on the base for limiting the position of the seed crystal on the base; an adhesive processing device including a processing chamber and an adhesive application unit, the processing chamber being connected to the adhesive application unit, the processing chamber being used to perform thermal activation treatment on the adhesive, and the adhesive application unit being used to apply the thermally activated adhesive to the base; and a pressing device, the movable end of which is adapted to move vertically to press the seed crystal onto the base.

[0006] Optionally, it may also include an intermediate layer adapted to be pressed between the base and the seed crystal.

[0007] Optionally, the base is provided with a first flow channel, and the intermediate layer is provided with a second flow channel. When the intermediate layer is placed on the base, the second flow channel and the first flow channel are aligned with each other in the vertical direction.

[0008] Optionally, the seed crystal has microgrooves on its bonding surface for bonding with the base.

[0009] Optionally, it may also include: a base fixing platform, the base fixing platform being used to place the base, the base fixing platform being provided with a positioning member, the positioning member being adapted to be sleeved around the base and concentrically arranged with the base, the top height of the positioning member being lower than the top height of the base.

[0010] Optionally, the inner wall of the positioning component is provided with an adsorption groove, which is connected to an external vacuum device to create a negative pressure at the adsorption groove to adsorb the base.

[0011] Optionally, the positioning member is further provided with an exhaust groove and a guide groove. The exhaust groove is disposed on the outer wall of the positioning member, and the guide groove connects the exhaust groove and the inner wall of the positioning member.

[0012] Optionally, the depth of the guide groove gradually increases in the vertical direction from the inner wall of the positioning member to the outer wall of the positioning member.

[0013] Optionally, the limiting device includes a limiting frame, which is sleeved around the base and concentrically arranged with the base, and the top height of the limiting frame is higher than the top height of the base.

[0014] Optionally, the height of the limiting frame in the vertical direction is 2 to 3 times that of the seed crystal.

[0015] Optionally, the limiting device further includes an elastic buffer layer, which is disposed on the inner wall of the limiting frame. The elastic buffer layer has a plurality of elastic protrusions, which are evenly distributed in a ring along the inner wall of the elastic buffer layer.

[0016] Optionally, the processing chamber is provided with a first heating unit and a first temperature sensor. The first heating unit is used to control the temperature inside the processing chamber, and the first temperature sensor is used to detect the temperature inside the processing chamber.

[0017] Optionally, the processing chamber includes an insulation layer, which is disposed on the chamber wall.

[0018] Optionally, the adhesive application unit includes an adhesive storage container, an adhesive application nozzle, and a peristaltic pump. The adhesive storage container is connected to the processing chamber and the adhesive application nozzle. The peristaltic pump is used to deliver the adhesive in the adhesive storage container to the adhesive application nozzle, and the adhesive application nozzle is used to apply the adhesive to the surface of the base.

[0019] Optionally, the adhesive application unit further includes a first moving device connected to the adhesive application nozzle, the first moving device being used to control the movement of the adhesive application nozzle.

[0020] Optionally, the glue application unit further includes a flow controller, which is disposed between the peristaltic pump and the glue application nozzle, and is used to control the glue output of the glue application nozzle.

[0021] Optionally, the adhesive application unit further includes a first pressure controller, which is disposed on the adhesive application nozzle and is used to control the adhesive dispensing pressure of the adhesive application nozzle.

[0022] Optionally, the adhesive application unit further includes a distance sensor for measuring the distance between the adhesive application nozzle and the base surface.

[0023] Optionally, it further includes: a control unit, which is electrically connected to the first moving device, the flow controller, the first pressure controller and the ranging sensor, and the control unit is used to control the moving speed of the first moving device according to the signal of the ranging sensor, and / or control the first pressure controller to adjust the dispensing pressure of the adhesive nozzle, and / or control the flow sensor to adjust the dispensing volume of the adhesive nozzle.

[0024] Optionally, the adhesive treatment device further includes an inert gas purging unit, which is used to purge inert gas between the adhesive nozzle and the base.

[0025] Optionally, the pressing device includes a guide rod arranged in a vertical direction, and the movable end includes a movable pressure plate and a pressure head. The movable pressure plate is sleeved on the guide rod, and the pressure head is disposed at the bottom of the movable pressure plate. The movable pressure plate can slide up and down along the guide rod, thereby driving the pressure head to move in the vertical direction.

[0026] Optionally, the pressing device further includes a driving unit for driving the movable pressure plate to slide along the guide rod.

[0027] Optionally, the diameter of the pressure head is 1 / 3 to 1 / 2 of the diameter of the seed crystal.

[0028] Optionally, the pressing device further includes a second pressure controller, which is connected to the movable end and is used to control the pressure applied by the pressure head to the seed crystal.

[0029] Optionally, the pressure head is provided with a dynamic micro-vibration unit, which is used to make the pressure head vibrate with a vibration frequency between 10 Hz and 50 Hz and an amplitude of less than or equal to 0.05 mm.

[0030] Optionally, it may also include: a second moving device, the second moving device being used to control the movement of the pressing device in the horizontal direction.

[0031] Optionally, it may also include: a base heating unit, which is annular and arranged around the inside of the base.

[0032] Accordingly, this invention also provides a seed crystal bonding method using the aforementioned seed crystal bonding equipment, comprising: placing a base under an adhesive treatment device; performing thermal activation treatment on the adhesive using a treatment chamber; applying the thermally activated adhesive to the surface of the base using a coating unit; placing the adhesive-coated base on a base fixing platform; placing the seed crystal in a limiting device on the base; and controlling the movable end of the pressing device to move vertically to press the seed crystal onto the base.

[0033] Optionally, it further includes: providing an intermediate layer, placing the intermediate layer on the surface of the substrate coated with adhesive, and then placing the seed crystal on the intermediate layer.

[0034] Optionally, before placing the base under the adhesive treatment device, the method further includes: performing plasma activation treatment on the base, the intermediate layer, and the seed crystal.

[0035] Optionally, the thermal activation treatment includes three stages: the first stage is to keep warm at 10℃~35℃ for 3 minutes, the second stage is to raise the temperature to 20℃~60℃ and keep warm for 2 minutes, and the third stage is to keep warm at 15℃~40℃ for 1 minute.

[0036] Optionally, when the pressing device presses the seed crystal, it further includes: using a second moving device to control the pressing device to move in the horizontal direction, so that the pressing device rolls the seed crystal.

[0037] Optionally, after the pressing device rolls the seed crystal, the method further includes: activating the dynamic micro-vibration unit in the pressing head of the pressing device.

[0038] Optionally, when the dynamic micro-vibration unit is activated, the base heating unit located inside the base is also activated simultaneously to perform stepped heating. The stepped heating includes two stages: the first stage is to heat from 10℃ to 30℃ at a rate of 5℃ / min to 45℃ and hold for 2s to 5s; the second stage is to heat from 45℃ to 55℃ at a rate of 5℃ / min and hold for 8s to 12s.

[0039] Compared with the prior art, the technical solution of the embodiments of the present invention has the following beneficial effects: The seed crystal bonding equipment provided in this technical solution can limit the position of the seed crystal on the base through a limiting device, thereby achieving precise positioning of the seed crystal and facilitating a stable bond between the seed crystal and the base. Simultaneously, before bonding, the adhesive treatment device first performs a thermal activation treatment on the adhesive, increasing its activity and viscosity, thus improving the bond strength between the seed crystal and the base. Furthermore, the thermal activation process can also initially remove air bubbles from the adhesive, further reducing residual air bubbles between the seed crystal and the base, thereby improving the bonding quality.

[0040] Furthermore, a first flow channel is provided on the base, and a second flow channel is provided on the intermediate layer. When the intermediate layer is placed on the base, the second flow channel and the first flow channel are aligned vertically. The intermediate layer between the seed crystal and the base forms a buffer layer between them and prevents seed crystal slippage, thereby improving the adhesion between the seed crystal and the base. Additionally, the flow channels on both the intermediate layer and the base are aligned with each other. During the pressing of the seed crystal and the base, the first and second flow channels can serve as both overflow channels and venting channels, further reducing air bubbles between the seed crystal and the base and improving the bonding quality.

[0041] The seed crystal bonding method provided in this technical solution uses a treatment chamber to thermally activate the adhesive, which can improve the activity and viscosity of the adhesive and initially remove air bubbles in the adhesive. After bonding the seed crystal and the substrate, it can improve the bonding strength between the seed crystal and the substrate and reduce air bubbles between the seed crystal and the substrate, thereby improving the bonding quality. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of a seed crystal bonding device in one embodiment of the present invention; Figure 2 This is a schematic diagram of the adhesive coating unit in one embodiment of the present invention; Figure 3 This is a schematic diagram of the pressing device in one embodiment of the present invention; Figure 4 This is a schematic diagram of the movement of the pressing device in one embodiment of the present invention. Detailed Implementation

[0043] As described in the background section, current seed crystal bonding technologies still suffer from problems such as residual air bubbles and poor bonding quality.

[0044] To address the aforementioned problems, embodiments of the present invention provide a seed crystal bonding device and method. The bonding device includes a base, a limiting device, an adhesive treatment device, and a pressing device. The limiting device is disposed on the base to restrict the position of the seed crystal on the base. The adhesive treatment device performs thermal activation treatment on the adhesive, which can improve the activity of the adhesive and thus increase its viscosity, and can also remove some air bubbles in the adhesive. Finally, the pressing device presses the seed crystal onto the base, thereby improving the bonding strength between the seed crystal and the base, reducing air bubbles between the seed crystal and the base, and improving the bonding quality.

[0045] To make the above-mentioned objectives, features and beneficial effects of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0046] refer to Figure 1 The seed crystal bonding device 1 includes: a base 10 for supporting the seed crystal; a limiting device (not shown) disposed on the base 10 for limiting the position of the seed crystal on the base 10; an adhesive processing device (not shown) including a processing chamber (not shown) and an adhesive application unit 31, the processing chamber being connected to the adhesive application unit 31, the processing chamber being used to perform thermal activation treatment on the adhesive, and the adhesive application unit being used to apply the thermally activated adhesive to the base 10; and a pressing device 40, the movable end of which is adapted to move along the vertical direction Z (reference). Figure 4 The movement is used to press the seed crystal onto the base 10.

[0047] In this embodiment, the base 10 is a graphite base, and the seed crystal is a silicon carbide seed crystal.

[0048] In this embodiment, the seed crystal bonding device 1 further includes a base fixing platform 11, which is used to place the base 10. A positioning member 12 is provided on the base fixing platform 11. The positioning member 12 is adapted to be sleeved around the base 10 and is concentrically arranged with the base 10. The top height of the positioning member 12 is lower than the top height of the base 10.

[0049] Furthermore, an adsorption groove is provided on the inner wall of the positioning member 12, and the adsorption groove is connected to an external vacuum device to create a negative pressure at the adsorption groove to adsorb the base 10.

[0050] In this embodiment, the positioning element 12 is annular and its shape is adapted to the shape of the base 10. The base 10 is embedded in the annular positioning element 12, and the base 10 is fixed in the positioning element 12 by the adsorption groove on the inner wall of the positioning element 12, thereby realizing the radial positioning of the base 10. In the subsequent bonding process with the seed crystal, it can ensure that the position is aligned with the seed crystal and improve the bonding quality.

[0051] Furthermore, the positioning member 12 is also provided with an exhaust groove and a guide groove. The exhaust groove is located on the outer wall of the positioning member 12, and the guide groove connects the exhaust groove and the inner wall of the positioning member.

[0052] Specifically, the guide groove can be set at the bottom of the positioning member 12, extending from the inner wall of the positioning member 12 to the outer wall, guiding the gas inside the positioning member 12, overflowing colloid, etc. to the external exhaust groove.

[0053] During the pressing process between the seed crystal and the base 10, gas, water vapor, and some adhesive colloid may be generated at the bottom of the base 10. Therefore, venting grooves and guide grooves are opened on the positioning part 12 to provide venting and overflow channels for the base 10 around and at the bottom, so as to avoid the situation where the base is lifted up due to the inability of gas to be discharged. This is conducive to the stable placement of the base 10, which in turn is conducive to the stability of subsequent adhesive application and bonding.

[0054] Furthermore, from the inner wall of the positioning member 12 to the outer wall of the positioning member 12, the depth of the guide groove gradually increases in the vertical direction. From the inner wall to the outer wall of the positioning member 12, a directional flow and exhaust gradient is formed, which is more conducive to the smooth discharge of gas.

[0055] In this embodiment, the limiting device includes a limiting frame, which is sleeved around the base 10 and concentrically arranged with the base. The top height of the limiting frame is higher than the top height of the base 10.

[0056] In this embodiment, the limiting frame is sleeved on the outer periphery of the base 10 protruding from the top of the positioning member 12, and the top height of the limiting frame is higher than the top height of the base 10. This allows the seed crystal to be completely embedded in the limiting frame, achieving radial positioning of the seed crystal, thereby aligning the positions of the seed crystal and the base. This helps to ensure the uniformity and stability of the bonding and is beneficial for subsequent crystal growth.

[0057] The height of the limiting frame in the vertical Z direction is 2 to 3 times that of the seed crystal. Setting the height of the limiting frame within this range ensures that the seed crystal is completely enclosed without adversely affecting the subsequent pressing process.

[0058] In this embodiment, the limiting device further includes an elastic buffer layer, which is disposed on the inner wall of the limiting frame. The elastic buffer layer has a plurality of elastic protrusions, which are evenly distributed in a ring along the inner wall of the elastic buffer layer.

[0059] The elastic buffer layer on the inner wall of the limiting frame can prevent the surface from being scratched when the seed crystal is embedded into the limiting frame, and at the same time ensure the positioning accuracy.

[0060] In this embodiment, the base 10 is further provided with a base heating unit, which is annular and arranged around the inside of the base 10. The annular base heating unit can provide a more uniform and stable heating temperature, and the heat is evenly emitted from the inside of the base 10, which will not cause uneven heating and cracking of the seed crystal.

[0061] In this embodiment, the base heating unit is a low-temperature heating unit with a heating temperature between 50°C and 80°C, which can meet the initial curing requirements of the adhesive.

[0062] In this embodiment, an intermediate layer (not shown) is also pressed between the seed crystal and the base 10.

[0063] In this embodiment, graphite paper is used in the intermediate layer. Graphite paper is placed between the base 10 and the seed crystal. Graphite paper can provide a buffer for the seed crystal, preventing it from slipping or cracking if the seed crystal is placed directly on the base 10. It can also reduce the thermal shock generated by the base 10 on the seed crystal.

[0064] In this embodiment, a first flow channel is provided on the base 10, and a second flow channel is provided on the intermediate layer. When the intermediate layer is placed on the base, the second flow channel and the first flow channel are aligned with each other in the vertical direction Z.

[0065] In this embodiment, the shapes and positions of the first flow guiding channel and the second flow guiding channel correspond to each other.

[0066] In some embodiments, the first and second flow channels may be configured as radial strip structures distributed from the center outwards, or as annular grooves distributed from the center outwards and radial grooves connecting the annular grooves.

[0067] The first flow channel is disposed on the surface of the base 10 for bonding with the seed crystal. The second flow channel on the intermediate layer is aligned with the first flow channel. During the subsequent pressing process, the overflowing adhesive can flow out through the first and second flow channels. The second flow channel and the first flow channel form an exhaust channel, which can discharge the air bubbles generated during the pressing process, reduce the air bubbles remaining between the seed crystal and the base 10, and help improve the bonding quality.

[0068] In this embodiment, microgrooves are formed on the bonding surface of the seed crystal used for pressing with the base. The microgrooves allow air bubbles to escape during the bonding process and guide the flow of the adhesive, resulting in a more uniform distribution of the adhesive on the seed crystal surface, thus improving the uniformity of the bond. Furthermore, the microgrooves increase the contact area between the adhesive and the seed crystal, and the interlocking structure between the microgrooves and the seed crystal further enhances the bonding strength between the seed crystal and the base 10.

[0069] In this embodiment, the adhesive treatment unit is used to perform thermal activation treatment on the adhesive, which can improve the activity of the adhesive, thereby increasing the viscosity of the adhesive. In addition, the thermal activation treatment can also initially remove air bubbles in the adhesive, which is more conducive to improving the bonding strength and bonding quality between the seed crystal and the substrate.

[0070] In this embodiment, a first heating unit and a first temperature sensor are provided inside the processing chamber. The first heating unit is used to control the temperature inside the processing chamber, and the first temperature sensor is used to detect the temperature inside the processing chamber.

[0071] Furthermore, the seed crystal bonding device 1 also includes a control unit, which is electrically connected to the first heating unit and the first temperature sensor. The control unit receives the temperature signal detected by the first temperature sensor and then controls the first heating unit according to the temperature signal to achieve temperature control in the processing chamber.

[0072] In this embodiment, the thermal activation treatment includes three stages: the first stage is to keep the temperature at 10℃~35℃ for 3 minutes; the second stage is to raise the temperature to 20℃~60℃ and keep it at that temperature for 2 minutes; and the third stage is to keep the temperature at 15℃~40℃ for 1 minute.

[0073] Preferably, the first stage of the thermal activation treatment is to keep the temperature at 25°C for 3 minutes, the second stage is to raise the temperature to 45°C and keep it at 45°C for 2 minutes, and the third stage is to keep the temperature at 35°C for 1 minute.

[0074] By using gradient temperature control, the internal stress of the adhesive is further released, thereby improving the adhesive's activity and viscosity.

[0075] In this embodiment, the processing chamber includes an insulation layer, which is disposed on the chamber wall.

[0076] In this embodiment, the adhesive application unit 32 is used to apply the heat-treated adhesive to the surface of the base 10. (See reference...) Figure 2The adhesive application unit 32 includes an adhesive storage container 321, an adhesive application nozzle 322, and a peristaltic pump. The adhesive storage container 321 is connected to the processing chamber and the adhesive application nozzle 322. The peristaltic pump is used to deliver the adhesive in the adhesive storage container 321 to the adhesive application nozzle 322. The adhesive application nozzle 322 is used to apply the adhesive to the surface of the base 10.

[0077] Furthermore, the adhesive application unit 32 also includes a first moving device (not shown), which is connected to the adhesive application nozzle 322 and is used to control the movement of the adhesive application nozzle 322.

[0078] In one embodiment, the first moving device includes a first slide rail and a first driving mechanism. The glue application unit is disposed on the first slide rail, and the first driving mechanism is connected to the glue application unit for driving the glue application unit to move on the first slide rail.

[0079] Furthermore, the glue application unit 32 also includes a flow controller, which is disposed between the peristaltic pump and the glue application nozzle, and is used to control the glue output of the glue application nozzle 322.

[0080] Furthermore, the glue application unit 32 also includes a first pressure controller, which is disposed on the glue application nozzle 322 and is used to control the glue dispensing pressure of the glue application nozzle 322.

[0081] Furthermore, the adhesive application unit 32 also includes a distance sensor, which is used to measure the distance between the adhesive application nozzle 322 and the surface of the base 10.

[0082] In this embodiment, the control unit is electrically connected to the first moving device, the flow controller, the first pressure controller, and the ranging sensor. The control unit is used to control the moving speed of the first moving device according to the signal from the ranging sensor, and / or control the first pressure controller to adjust the dispensing pressure of the adhesive nozzle, and / or control the flow sensor to adjust the dispensing volume of the adhesive nozzle.

[0083] It should be noted that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article indicates that the preceding and following related objects have an "or" relationship.

[0084] Specifically, in this embodiment of the invention, the control unit can control one or more of the following: the moving speed of the first moving device, the dispensing pressure of the adhesive nozzle, and the dispensing volume of the adhesive nozzle. For example, the control unit can control the first pressure controller to adjust the dispensing pressure of the adhesive nozzle; or, control the moving speed of the first moving device and control the flow sensor to adjust the dispensing volume of the adhesive nozzle; or, control the moving speed of the first moving device, control the first pressure controller to adjust the dispensing pressure of the adhesive nozzle, and control the flow sensor to adjust the dispensing volume of the adhesive nozzle.

[0085] Since the base surface is not completely flat and smooth, and there will be slight unevenness, it is necessary to adjust the amount of adhesive, the adhesive pressure, and the adhesive application rate in a timely manner according to the unevenness of the base surface.

[0086] In one embodiment, a distance sensor measures the distance between the adhesive nozzle 322 and the surface of the base 10, and compares it with a reference value. If the distance is less than the reference value, it indicates that the plane is convex, and the first pressure controller is controlled to reduce the adhesive dispensing pressure and / or the first moving device is controlled to increase the moving speed. If the distance is greater than the reference value, it indicates that the plane is concave, and the first pressure controller is controlled to increase the adhesive dispensing pressure and / or the first moving device is controlled to decrease the moving speed. A lower dispensing pressure and a faster dispensing rate result in less adhesive applied to the convex plane, leading to a thinner adhesive layer. Conversely, a higher dispensing pressure and a slower dispensing rate result in more adhesive applied to the concave plane, leading to a thicker adhesive layer. This effectively improves the uniformity of adhesive application on the surface of the base 10.

[0087] In specific implementation, the first pressure controller has a built-in pressure regulating valve. After receiving the pressure reduction command from the control unit, it reduces the driving air pressure acting on the glue storage container by adjusting the intake or exhaust volume of compressed air, thereby reducing the glue dispensing pressure of the glue nozzle. At the same time, it is equipped with the first pressure sensor to provide real-time feedback on the actual pressure, forming a closed loop to stabilize the glue dispensing pressure at the target value.

[0088] In a specific implementation, the control unit controls the pulse frequency or rotation of the motor of the first drive mechanism, changes the moving speed of the motion unit of the first drive mechanism, thereby achieving the acceleration or deceleration of the nozzle.

[0089] In this embodiment, the adhesive treatment device further includes an inert gas purging unit, which is used to purge inert gas between the adhesive nozzle 322 and the base 10.

[0090] When applying adhesive to the base 10, an inert gas atmosphere is created between the adhesive nozzle 322 and the base 10 to prevent the adhesive from oxidizing or being encapsulated by air bubbles, thereby improving the bonding quality of the adhesive.

[0091] In this embodiment, the inert gas purging unit and the adhesive application unit are both located inside the cover, and the cover contains an inert gas atmosphere, which is more conducive to creating an inert gas environment when applying the adhesive.

[0092] refer to Figure 4 The pressing device 40 includes a guide rod 41 arranged in the vertical direction Z, and the movable end includes a movable pressure plate 42 and a pressure head 43. The movable pressure plate 42 is arranged at the end of the guide rod 41, and the pressure head 43 is arranged at the bottom of the movable pressure plate 43. The movable pressure plate 42 and the pressure head 43 can move up and down in the vertical direction Z.

[0093] Furthermore, the pressing device also includes a driving unit, which is used to drive the movable pressure plate 42 and the pressure head 43 to move up and down in the vertical direction Z. The pressure of the pressure head 43 on the seed crystal causes the seed crystal to bond with the base 10.

[0094] The guide rod 41 ensures that the sliding of the movable pressure plate 42 in the vertical direction Z does not tilt, thereby ensuring that the pressure head 43 is aligned with the seed crystal during pressing, which is beneficial to improving the bonding quality.

[0095] In this embodiment, the pressure head 43 is hemispherical, and its diameter is 1 / 3 to 1 / 2 of the seed crystal diameter. Controlling the size of the pressure head 43 can prevent damage to the seed crystal.

[0096] In this embodiment, the bottom of the pressure head 43 is provided with an anti-slip texture, the depth of which is between 0.1 micrometers and 0.3 micrometers. The anti-slip texture is beneficial to the stability of the contact between the pressure head 43 and the seed crystal, thereby ensuring uniform pressure application and preventing damage to the seed crystal.

[0097] In this embodiment, the pressure head 43 is made of silicon carbide.

[0098] Continue to refer to Figure 4 The pressing device 40 further includes a second pressure controller, which is connected to the movable end and is used to control the pressure applied by the pressure head to the seed crystal.

[0099] In this embodiment, the second pressure controller includes a second pressure sensor, a buffer spring 44, and a pressure adjustment module. The pressure sensor is disposed inside the guide rod 41. One end of the buffer spring 44 is connected to the end of the guide rod 41, and the other end of the buffer spring 44 is connected to the top of the movable pressure plate 42. The pressure adjustment module is used to adjust the compression of the buffer spring to achieve precise pressure control.

[0100] In specific implementation, the pressure adjustment module adopts a threaded adjustment structure. The pressure adjustment module includes an adjusting nut (not shown), which is sleeved on the outside of the guide rod 41, with its lower end abutting against the movable pressure plate 42. The second pressure sensor collects the actual pressing force of the pressure head 43 in real time and feeds it back to the control unit. When the actual pressing force deviates from the preset target value, the control unit drives the adjusting nut to move axially along the guide rod 41, changing the elastic force of the buffer spring 44 by changing the pressure on the buffer spring 44, thereby changing the magnitude of the pressing force. Specifically, when the actual pressing force is less than the preset target value, the adjusting nut moves axially downward along the guide rod 41, increasing the compression of the buffer spring 44 and increasing the spring elastic force to increase the pressing force; when the actual pressing force is greater than the preset target value, the adjusting nut moves axially upward along the guide rod 41, decreasing the compression of the buffer spring 44 and decreasing the spring elastic force to decrease the pressing force, until the actual pressing force matches the preset target value, achieving precise pressure control.

[0101] In this embodiment, a dynamic micro-vibration unit is provided inside the pressure head 43. The dynamic micro-vibration unit is used to make the pressure head vibrate with a vibration frequency between 10 Hz and 50 Hz and an amplitude of less than or equal to 0.05 mm.

[0102] The dynamic micro-vibration unit is used to generate high-frequency micro-vibration of the pressure head 43. After pressing, the dynamic micro-vibration unit is activated, and the pressure head 43 continuously performs high-frequency micro-vibration on the seed crystal, which can remove air bubbles between the seed crystal and the base 10, reduce air bubble residue, and improve the bonding quality.

[0103] In this embodiment, the dynamic micro-vibration unit adopts a piezoelectric ceramic micro-vibration unit; in other embodiments, the dynamic micro-vibration unit may also adopt other structures such as electromagnetic micro-vibration or ultrasonic micro-vibration.

[0104] In this embodiment, a ceramic fiber heat insulation pad is also provided between the pressure head and the dynamic micro-vibration unit, which can reduce the impact of heat transmitted from the pressure head on the working stability of the oscillator of the dynamic micro-vibration unit when the pressure head comes into contact with the seed crystal.

[0105] refer to Figure 3 In this embodiment, the pressing device 40 further includes a second moving device 50, which is used to control the movement of the pressing device 40 in the horizontal direction.

[0106] The second moving device 50 can move the pressing device 40 in the horizontal X or X+Y direction, wherein the X and Y directions are perpendicular to each other. The movement of the pressing device 40 can roll and press the seed crystal, ensuring that the seed crystal can make uniform contact with the base, and further improving the uniformity and quality of the bonding between the seed crystal and the base.

[0107] When the seed crystal is large, the pressing device 40 can be controlled to move along multiple trajectories, thereby ensuring that the pressing range of the pressing head 43 can completely cover the seed crystal; when the seed crystal is small, the pressing device 40 can be controlled to move only in one horizontal direction, for example, only in a straight line along the X direction.

[0108] In this embodiment, the second moving device 50 includes a second slide rail 51 and a second driving mechanism. The pressing device 40 is mounted on the second slide rail 51, and the second driving mechanism is used to drive the pressing device 40 to slide on the second slide rail 51.

[0109] In this embodiment, the second slide rail 51 extends along the X direction.

[0110] In this embodiment, limit sensors are also provided at both ends of the second slide rail 51. The limit sensors are used to limit the stroke of the pressing device 40 on the second slide rail 51, thereby ensuring that the pressing device 40 accurately presses the seed crystal and avoids the risk of damaging the seed crystal by exceeding the stroke range.

[0111] Accordingly, this embodiment of the invention also provides a seed crystal bonding method, using the above-described seed crystal bonding device 1, the bonding method comprising: S1. Place the base under the adhesive treatment device.

[0112] In this embodiment, before step S1, the base 10, the intermediate layer and the seed crystal need to be pretreated. The pretreatment includes plasma activation treatment of the base 10, the intermediate layer and the seed crystal.

[0113] Specifically, argon plasma activation treatment is applied to the surface of the base 10 bonded to the seed crystal, the bonding surface of the seed crystal, and the intermediate layer. This can remove impurities from the surface of the base and the seed crystal, and also improve the wettability of the adhesive in the intermediate layer, which is beneficial for the subsequent bonding between the seed crystal and the base.

[0114] The parameters for the plasma activation treatment include: power between 100 watts and 150 watts, time between 3 min and 5 min, and argon flow rate between 20 sccm and 30 sccm.

[0115] In addition, after plasma activation treatment, the process also includes: forming a first flow channel on the surface of the base 10, forming a second flow channel on the intermediate layer by laser processing, and forming microgrooves on the seed crystal bonding surface by inductively coupled plasma etching process.

[0116] The formation of microgrooves on the seed crystal bonding surface can be carried out continuously after plasma activation treatment.

[0117] After pretreatment, the base 10 is placed under the adhesive treatment device in preparation for the adhesive application process.

[0118] S2. The adhesive is thermally activated using a treatment chamber.

[0119] In this embodiment, the thermal activation treatment includes three stages: the first stage is to keep the temperature at 10℃~35℃ for 3 minutes; the second stage is to raise the temperature to 20℃~60℃ and keep it at that temperature for 2 minutes; and the third stage is to keep the temperature at 15℃~40℃ for 1 minute.

[0120] Preferably, the first stage of the thermal activation treatment is to keep the temperature at 25°C for 3 minutes, the second stage is to raise the temperature to 45°C and keep it at 45°C for 2 minutes, and the third stage is to keep the temperature at 35°C for 1 minute.

[0121] During the heat activation process, the adhesive is stirred at a low speed of 30 rpm to disperse air bubbles in the adhesive and prevent excessive air bubbles from affecting the bonding quality.

[0122] S3. The adhesive, which has undergone heat activation treatment, is applied to the base surface using an adhesive coating unit.

[0123] In this embodiment, when applying the adhesive, the inert gas purging unit is turned on and inert gas is introduced. The inert gas can be argon, and nitrogen is introduced as an auxiliary gas. The ratio of argon to nitrogen is 3:1.

[0124] In this embodiment, the thickness of the adhesive coating on the surface of the base 10 is between 0.1 mm and 0.3 mm, the coating speed is between 5 mm / s and 8 mm / s, and the coating speed is adjusted in conjunction with the inert gas flow rate.

[0125] S4. Move the base under the pressing device.

[0126] In this embodiment, after the adhesive is applied to the surface of the base 10, the base 10 is moved to the bottom of the pressing device by the first moving device, and the base 10 is embedded in the positioning member 12 on the base fixing platform 11; the vacuum device is activated to generate negative pressure at the adsorption groove of the positioning member 12 to adsorb and fix the base 10.

[0127] In this embodiment, the method further includes: laying an intermediate layer flat on the surface of the base 10, with the second flow channel on the intermediate layer aligned with the first flow channel on the surface of the base 10.

[0128] S5. Place the seed crystal in the limiting device on the base.

[0129] In this embodiment, the seed crystal is placed in the limiting device to achieve alignment between the seed crystal and the base 10.

[0130] S6. Control the moving end of the pressing device to move vertically and press the seed crystal onto the base.

[0131] In this embodiment, the pressing device 40 is controlled to move horizontally by the second moving device, so that the pressing device 40 rolls the seed crystal, and the second driving mechanism drives the pressing device 40 to move at a constant speed on the second slide rail.

[0132] The pressure applied to the seed crystal by the pressure head 43 is between 0.3 MPa and 0.8 MPa.

[0133] In this embodiment, after rolling, the process further includes: turning off the second drive mechanism, stopping the pressure head 43 above the seed crystal, and simultaneously activating the dynamic micro-vibration unit in the pressure head of the pressing device, which generates high-frequency micro-vibration to vent the adhesive between the seed crystal and the base.

[0134] In this embodiment, when the dynamic micro-vibration unit is activated, the base heating unit located inside the base 10 is also activated simultaneously to perform stepped heating and pre-curing of the adhesive.

[0135] In this embodiment, the stepped heating includes two stages: the first stage is to heat from 10℃ to 30℃ to 45℃ at a rate of 5℃ / min and hold for 2s to 5s; the second stage is to heat from 45℃ to 55℃ at a rate of 5℃ / min and hold for 8s to 12s.

[0136] Preferably, the first stage of the stepped heating is to raise the temperature from 30°C to 45°C at a rate of 5°C / min and hold for 5 seconds; the second stage is to raise the temperature from 45°C to 55°C at a rate of 5°C / min and hold for 10 seconds.

[0137] Finally, the bonded seed crystal-base assembly is removed from the seed crystal bonding equipment and subjected to subsequent high-temperature curing treatment.

[0138] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A seed crystal bonding device, characterized in that, include: A base for supporting the seed crystal; A limiting device is disposed on the base, and the limiting device is used to limit the position of the seed crystal on the base; An adhesive treatment apparatus includes a treatment chamber and an adhesive application unit. The treatment chamber is connected to the adhesive application unit. The treatment chamber is used to perform thermal activation treatment on the adhesive, and the adhesive application unit is used to apply the thermally activated adhesive onto the base. A pressing device, wherein the movable end of the pressing device is adapted to move in a vertical direction to press the seed crystal onto the base.

2. The seed crystal bonding device according to claim 1, characterized in that, Also includes: An intermediate layer, which is adapted to be pressed between the base and the seed crystal.

3. The seed crystal bonding device according to claim 2, characterized in that, The base is provided with a first flow channel, and the intermediate layer is provided with a second flow channel. When the intermediate layer is placed on the base, the second flow channel and the first flow channel are aligned with each other in the vertical direction.

4. The seed crystal bonding device according to claim 1, characterized in that, The seed crystal has microgrooves on its bonding surface for bonding with the base.

5. The seed crystal bonding device according to claim 1, characterized in that, Also includes: A base fixing platform is provided for placing the base. A positioning element is provided on the base fixing platform. The positioning element is adapted to be sleeved around the base and is concentrically arranged with the base. The top height of the positioning element is lower than the top height of the base.

6. The seed crystal bonding device according to claim 5, characterized in that, An adsorption groove is provided on the inner wall of the positioning component. The adsorption groove is connected to an external vacuum device to create a negative pressure at the adsorption groove to adsorb the base.

7. The seed crystal bonding device according to claim 5, characterized in that, The positioning component is also provided with an exhaust groove and a flow guide groove. The exhaust groove is located on the outer wall of the positioning component, and the flow guide groove connects the exhaust groove and the inner wall of the positioning component.

8. The seed crystal bonding device according to claim 7, characterized in that, From the inner wall of the positioning member to the outer wall of the positioning member, the depth of the guide groove gradually increases in the vertical direction.

9. The seed crystal bonding device according to claim 1, characterized in that, The limiting device includes a limiting frame, which is sleeved around the base and concentrically arranged with the base, and the top height of the limiting frame is higher than the top height of the base.

10. The seed crystal bonding device according to claim 9, characterized in that, The height of the limiting frame in the vertical direction is 2 to 3 times that of the seed crystal.

11. The seed crystal bonding device according to claim 9, characterized in that, The limiting device further includes an elastic buffer layer, which is disposed on the inner wall of the limiting frame. The elastic buffer layer has a plurality of elastic protrusions, which are evenly distributed in a ring along the inner wall of the elastic buffer layer.

12. The seed crystal bonding device according to claim 1, characterized in that, The processing chamber is equipped with a first heating unit and a first temperature sensor. The first heating unit is used to control the temperature inside the processing chamber, and the first temperature sensor is used to detect the temperature inside the processing chamber.

13. The seed crystal bonding device according to claim 12, characterized in that, The processing chamber includes an insulation layer, which is disposed on the chamber wall.

14. The seed crystal bonding device according to claim 1, characterized in that, The adhesive application unit includes an adhesive storage container, an adhesive application nozzle, and a peristaltic pump. The adhesive storage container is connected to the processing chamber and the adhesive application nozzle. The peristaltic pump is used to deliver the adhesive in the adhesive storage container to the adhesive application nozzle, and the adhesive application nozzle is used to apply the adhesive to the surface of the base.

15. The seed crystal bonding device according to claim 14, characterized in that, The adhesive application unit further includes a first moving device, which is connected to the adhesive application nozzle and is used to control the movement of the adhesive application nozzle.

16. The seed crystal bonding device according to claim 15, characterized in that, The adhesive application unit also includes a flow controller, which is disposed between the peristaltic pump and the adhesive application nozzle. The flow controller is used to control the amount of adhesive dispensed from the adhesive application nozzle.

17. The seed crystal bonding device according to claim 16, characterized in that, The adhesive application unit further includes a first pressure controller, which is disposed on the adhesive application nozzle and is used to control the adhesive dispensing pressure of the adhesive application nozzle.

18. The seed crystal bonding device according to claim 17, characterized in that, The adhesive application unit also includes a distance sensor, which is used to measure the distance between the adhesive application nozzle and the base surface.

19. The seed crystal bonding device according to claim 18, characterized in that, Also includes: The control unit is electrically connected to the first moving device, the flow controller, the first pressure controller, and the ranging sensor. The control unit is used to control the moving speed of the first moving device according to the signal from the ranging sensor, and / or control the first pressure controller to adjust the dispensing pressure of the adhesive nozzle, and / or control the flow sensor to adjust the dispensing volume of the adhesive nozzle.

20. The seed crystal bonding device according to claim 13, characterized in that, The adhesive treatment device further includes an inert gas purging unit, which is used to purge inert gas between the adhesive nozzle and the base.

21. The seed crystal bonding device according to claim 1, characterized in that, The pressing device includes a guide rod arranged in a vertical direction. The movable end includes a movable pressure plate and a pressure head. The movable pressure plate is sleeved on the guide rod, and the pressure head is located at the bottom of the movable pressure plate. The movable pressure plate can slide up and down along the guide rod, thereby driving the pressure head to reciprocate in the vertical direction.

22. The seed crystal bonding device according to claim 21, characterized in that, The pressing device further includes a driving unit, which drives the movable pressure plate to slide along the guide rod.

23. The seed crystal bonding device according to claim 21, characterized in that, The diameter of the pressure head is 1 / 3 to 1 / 2 of the diameter of the seed crystal.

24. The seed crystal bonding device according to claim 21, characterized in that, The pressing device further includes a second pressure controller, which is connected to the movable end and is used to control the pressure applied by the pressure head to the seed crystal.

25. The seed crystal bonding device according to claim 21, characterized in that, The pressure head is equipped with a dynamic micro-vibration unit, which is used to make the pressure head vibrate with a frequency between 10 Hz and 50 Hz and an amplitude of less than or equal to 0.05 mm.

26. The seed crystal bonding device according to claim 21, characterized in that, Also includes: The second moving device is used to control the movement of the pressing device in the horizontal direction.

27. The seed crystal bonding device according to claim 1, characterized in that, Also includes: A base heating unit, which is ring-shaped and arranged around the inside of the base.

28. A seed crystal bonding method, characterized in that, Using the seed crystal bonding apparatus as described in any one of claims 1 to 27, comprising: Place the base below the adhesive treatment device; The adhesive is thermally activated using a treatment chamber. The adhesive, after being heat-activated, is applied to the surface of the base using an adhesive application unit. Place the adhesive-coated base on the base fixing platform; The seed crystal is placed in the limiting device on the base; The movable end of the control pressing device moves vertically to press the seed crystal onto the base.

29. The seed crystal bonding method according to claim 28, characterized in that, Also includes: An intermediate layer is provided, which is placed on the surface of the base coated with adhesive, and then the seed crystal is placed on the intermediate layer.

30. The seed crystal bonding method according to claim 29, characterized in that, Before placing the base under the adhesive treatment device, the process further includes: performing plasma activation treatment on the base, the intermediate layer, and the seed crystal.

31. The seed crystal bonding method according to claim 28, characterized in that, The thermal activation treatment includes three stages: the first stage is to keep the temperature at 10℃~35℃ for 3 minutes; the second stage is to raise the temperature to 20℃~60℃ and keep it at that temperature for 2 minutes; and the third stage is to keep the temperature at 15℃~40℃ for 1 minute.

32. The seed crystal bonding method according to claim 28, characterized in that, When the pressing device presses the seed crystal, it also includes: using a second moving device to control the pressing device to move in the horizontal direction, so that the pressing device can roll and press the seed crystal.

33. The seed crystal bonding method according to claim 32, characterized in that, After the pressing device rolls the seed crystal, the process further includes: activating the dynamic micro-vibration unit in the pressing head of the pressing device.

34. The seed crystal bonding method according to claim 33, characterized in that, When the dynamic micro-vibration unit is activated, the base heating unit located inside the base is also activated to perform stepped heating. The stepped heating includes two stages: the first stage is to heat from 10℃ to 30℃ at a rate of 5℃ / min to 45℃ and hold for 2s to 5s; the second stage is to heat from 45℃ to 55℃ at a rate of 5℃ / min and hold for 8s to 12s.

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