A method for controlling the Z-axis height of tilt mounting

Abstract

This invention relates to the field of semiconductor mounting technology and discloses a method for controlling the Z-axis height during tilted mounting. The method includes the following steps: moving the mounting head above a Z-axis correction sensor, acquiring the mounting head coordinates, and setting an initial height based on the current mounting head coordinates; moving the mounting head down to touch the Z-axis correction sensor, recording the Z-axis coordinates, and setting the mating height between the mounting head and the Z-axis correction sensor; acquiring the coordinates and values ​​of a laser beam, and calculating a first fixed value based on the laser coordinates and values; calculating a second fixed value based on the mating height between the mounting head and the Z-axis correction sensor, and the Z-axis coordinates of the mounting head; correcting the second fixed value against the first fixed value to obtain a relative verification value between the mounting head and the Z-axis correction sensor; and verifying the new mating height between the mounting head and the Z-axis correction sensor based on the laser coordinates and values. This method effectively corrects the height during tilted mounting of products.

Description

Technical Field

[0001] This invention relates to the field of semiconductor mounting technology, and more specifically to a method for controlling the Z-axis height of tilted mounting. Background Technology

[0002] The increasingly stringent requirements of high-end manufacturing for precision mounting processes, especially in the context of rapid development in fields such as electronic packaging, semiconductor assembly, and Mini / Micro LED displays, have led to ever-increasing demands for efficiency. Traditional planar mounting relies on pressure sensors to control the pressure termination position, resulting in a relatively large tolerance for the pre-mount height Z.

[0003] With technological innovation, in order to improve product reliability, the product design adopts a slotting method to restrict the product. Therefore, the mounting method needs to be changed from the traditional flat mounting to the tilt mounting, that is, the product needs to be inserted into the corresponding slot first, and then rotated and flattened downwards.

[0004] In tilt mounting applications, the mount must first be rotated to the designed angle and then horizontally moved to fit into the groove. Because the gap between the product and the mounting bracket is very small and the position is fixed, the initial mounting height can only be determined visually, resulting in a random initial height. If the Z-axis height deviates, the mount may collide with the edge of the groove, causing collisions during product mounting and leading to product defects. Therefore, a method for precise Z-axis height calibration and dynamic compensation in tilt mounting is needed for Z-axis height control. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a novel method for controlling the Z-axis height in tilt mounting, thereby resolving the problem of inaccurate Z-axis height calibration in existing tilt mounting applications.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A method for controlling the Z-axis height during tilted mounting, used to correct the height of a product during tilted mounting, includes a mounting device, the mounting device including a mounting head, and the method for controlling the Z-axis height during tilted mounting includes the following steps:

[0008] Step S1: Move the placement head above the Z-axis correction sensor, obtain the placement head coordinate values, and set the initial height based on the current placement head coordinate values;

[0009] Step S2: Move the placement head down so that it touches the Z-axis correction sensor, record the Z-axis coordinate of touching the Z-axis sensor, and set the current mating height between the placement head and the Z-axis correction sensor;

[0010] Step S3: Move the laser set on the side of the placement head above the Z-axis correction sensor, obtain the coordinate value and numerical value of the laser, and calculate the coordinate value and numerical value of the laser to obtain the first fixed value;

[0011] Step S4: Calculate the mating height between the placement head and the Z-axis correction sensor, as well as the Z-axis coordinate of the placement head, to obtain a second fixed value; then correct it with the first fixed value to obtain the relative verification value between the placement head and the Z-axis correction sensor, and verify the new mating height between the placement head and the Z-axis correction sensor based on the coordinate and numerical values ​​of the laser.

[0012] Furthermore, step S1 includes the following steps:

[0013] Step S11: Set calibration points on the Z-axis calibration sensor;

[0014] Step S12: Move the placement head above the Z-axis correction sensor and record the current placement head coordinate value Z;

[0015] Step S13: Set the initial height z using the mounting head coordinate value Z.

[0016] Furthermore, in step S2, when the placement head touches the Z-axis correction sensor, the Z-axis coordinate Z1 of the placement head touching the Z-axis sensor is recorded, and the mating height Z0 between the placement head and the Z-axis correction sensor is 0.

[0017] Furthermore, step S3 includes the following steps:

[0018] Step S31: Switch to laser, move the laser cursor to the center position of the Z-axis correction sensor, and record the current laser coordinate value Z2 and value H;

[0019] Step S32: Calculate the coordinate value Z2 and the numerical value H of the laser to obtain the first fixed value A, Z2+H=A.

[0020] Furthermore, step S4 includes the following steps:

[0021] Step S41: Calculate the second fixed value B based on the mating height between the placement head and the Z-axis correction sensor, and the Z-axis coordinate of the placement head, Z1+Z0=B;

[0022] Step S42, calculate the relative check value C = BA = (Z1 + Z0) - (Z2 + H);

[0023] Step S43: During mounting, the laser acquires the coordinate values ​​Z2′ and H′ in real time;

[0024] Step S44, substitute the calibration relationship: Z1 + Z0′ = C + Z2′ + H′, to verify the placement height Z0′ of the placement head.

[0025] Furthermore, in step S4, the compensation formula for the actual mounting height Z0′ of the mounting head is: ΔZ = (C + Z2′ + H′) - (Z1 + Z0′).

[0026] Furthermore, the mounting equipment includes a robotic arm, and the mounting head is disposed at the working end of the robotic arm.

[0027] Furthermore, the mounting head is provided with an anti-collision buffer during the horizontal movement phase, and stops moving when the distance between the mounting body and the groove edge of the object being mounted is less than the anti-collision buffer.

[0028] Furthermore, the Z-axis correction sensor is a contact-triggered sensor.

[0029] Furthermore, the laser is a point laser rangefinder.

[0030] Compared to existing technologies, the present invention, employing the above-mentioned solution, is applicable to scenarios with stringent requirements for initial height accuracy, such as tilt mounting and groove embedding. To ensure initial height accuracy, a Z-axis correction sensor is introduced. The bonding head touches the Z-axis correction sensor, recording the Z-axis coordinate Z1 of the touch and the engagement height Z0 between the sensor and the bonding head. Then, a laser is used to illuminate the sensor surface, recording the Z-axis coordinate Z2 and the laser value H. Using Z2+H=A, Z1+Z0=B, and Z1+Z0-Z2-H=BA=C, the initial calibration relationship yields Z1+Z0′=C+Z2′+H′, where Z0′ is the mounting height of the bonding head from the mounting surface. By setting Z0′ according to the initial actual specifications of the product, the tilt insertion height can be ensured to match the actual product design height, greatly improving the movement accuracy of the equipment and possessing significant market application value. Attached Figure Description

[0031] Figure 1 This is a flowchart of a tilt mounting Z-axis height control method according to an embodiment of the present invention. Detailed Implementation

[0032] To facilitate understanding of the present invention by those skilled in the art, specific embodiments of the present invention are described below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0033] It should be noted that when a component is referred to as being "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "mounted," "fixed," "front," "rear," and similar expressions used in this specification are for illustrative purposes only.

[0034] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0035] One embodiment of the present invention is as follows: Figure 1 As shown, the tilt mounting Z-axis height control method is used to correct the height of a product during tilt mounting. It includes a mounting device, which includes a mounting head. The tilt mounting Z-axis height control method includes the following steps:

[0036] Step S1: Move the placement head above the Z-axis correction sensor, obtain the placement head coordinate values, and set the initial height based on the current placement head coordinate values;

[0037] Step S2: Move the placement head down so that it touches the Z-axis correction sensor, record the Z-axis coordinate of touching the Z-axis sensor, and set the current mating height between the placement head and the Z-axis correction sensor;

[0038] Step S3: Move the laser set on the side of the placement head above the Z-axis correction sensor, obtain the coordinate value and numerical value of the laser, and calculate the coordinate value and numerical value of the laser to obtain the first fixed value;

[0039] Step S4: Calculate the mating height between the placement head and the Z-axis correction sensor, as well as the Z-axis coordinate of the placement head, to obtain a second fixed value; then correct it with the first fixed value to obtain the relative verification value between the placement head and the Z-axis correction sensor, and verify the new mating height between the placement head and the Z-axis correction sensor based on the coordinate and numerical values ​​of the laser.

[0040] The tilt mounting Z-axis height control method in this embodiment is suitable for tilt mounting of semiconductors and is applicable to scenarios with stringent requirements for initial height accuracy, such as tilt mounting and recess embedding. To ensure the accuracy of the initial height, a Z-axis correction sensor is introduced. The mounting head touches the Z-axis correction sensor and records the Z-axis coordinate Z1 of the touch. The height of the sensor and the mounting head mating is Z0. Then, a laser is used to illuminate the sensor surface and record the Z-axis coordinate Z2 and the laser value H. Using Z2+H=A, Z1+Z0=B, Z1+Z0-Z2-H=BA=C, the initial calibration relationship can be used to obtain Z1+Z0′=C+Z2′+H′, where Z0′ is the mounting height of the mounting head from the mounting surface. Then, according to the initial actual specifications of the product, setting Z0′ can ensure that the tilt insertion height is mounted according to the actual product design height, which greatly improves the movement accuracy of the equipment.

[0041] In this embodiment, step S1 includes the following steps:

[0042] Step S11: Set calibration points on the Z-axis calibration sensor;

[0043] Step S12: Move the placement head above the Z-axis correction sensor and record the current placement head coordinate value Z;

[0044] Step S13: Set the initial height z using the mounting head coordinate value Z.

[0045] Specifically, the placement head is moved above the Z-axis correction sensor, and a camera set on the side of the placement head takes a picture. This height is used as the initial height of the robot arm of the placement equipment, that is, the robot arm uses this position as the pre-placement height, and the placement head is slowly lowered to place the object picked up by the placement head onto the object to be placed.

[0046] In this embodiment, in step S2, when the placement head touches the Z-axis correction sensor, the Z-axis coordinate Z1 of the placement head touching the Z-axis sensor is recorded, and the mating height Z0 between the placement head and the Z-axis correction sensor is 0.

[0047] Specifically, the mating height Z0 between the placement head and the Z-axis correction sensor is the safe height for tilting the placement head. In practice, the mating height Z0′ between the placement head and the Z-axis correction sensor is greater than Z0. When the placement head descends to this height, the placement body is then moved horizontally into the groove, and then the placement body is turned upright for placement, so as to ensure that the tilting height is placed according to the actual product design height.

[0048] In this embodiment, step S3 includes the following steps:

[0049] Step S31: Switch to laser, move the laser cursor to the center position of the Z-axis correction sensor, and record the current laser coordinate value Z2 and value H;

[0050] Step S32: Calculate the coordinate value Z2 and the numerical value H of the laser to obtain the first fixed value A, Z2+H=A.

[0051] Specifically, if the initial height z of the placement head is 50, the laser coordinate value Z2 and the numerical value H are added together to 50. This value is constant. However, as the placement head slowly descends, the laser coordinate value Z2 gradually increases and the numerical value H gradually decreases to achieve dynamic height compensation.

[0052] In this embodiment, step S4 includes the following steps:

[0053] Step S41: Calculate the second fixed value B based on the mating height between the placement head and the Z-axis correction sensor, and the Z-axis coordinate of the placement head, Z1+Z0=B;

[0054] Step S42, calculate the relative check value C = BA = (Z1 + Z0) - (Z2 + H);

[0055] Step S43: During mounting, the laser acquires the coordinate values ​​Z2′ and H′ in real time;

[0056] Step S44, substitute the calibration relationship: Z1 + Z0′ = C + Z2′ + H′, to verify the placement height Z0′ of the placement head.

[0057] Specifically, the mounting height Z0′=Z1+Z0-C-Z2′-H′ of the mounting head is dynamically verified in real time through the coordinated calibration of the Z-axis correction sensor and the point laser, and real-time height compensation based on the C value.

[0058] In this embodiment, the formula for calculating the compensation amount of the actual mounting height Z0′ of the mounting head in step S4 is: ΔZ = (C + Z2′ + H′) - (Z1 + Z0′).

[0059] Specifically, the parameter verification of the relative verification value C needs to be averaged through three repeated calibrations, and the variance value needs to be less than 0.005 mm. When ΔZ exceeds the set threshold, the system will automatically trigger the recalibration process.

[0060] Specifically, the laser acquires the coordinate values ​​Z2′ and H′ in real time and monitors the fluctuations of Z2′ and H′ in real time. When the standard deviation of 5 consecutive sampling points is greater than 0.03mm, the mounting is paused.

[0061] In this embodiment, the tilt mounting Z-axis height control method establishes a mapping relationship between the Z-axis coordinate and the laser value through a Z-axis correction sensor and a point laser; combined with a dynamic height compensation algorithm, the mounting height is corrected in real time by associating the robot coordinate, sensor parameters and design height with the relative verification value C.

[0062] Specifically, the robotic arm manipulates the fitting head to touch the Z-axis correction sensor and records the triggered Z-axis coordinate Z1; the surface of the sensor is probed by a point laser, and the Z-axis coordinate Z2 and the laser ranging value H are recorded at this time.

[0063] The first fixed value A is the fixed value of the laser ranging system, Z2+H=A;

[0064] The second set value B is the set value of the sensor triggering system, Z1+Z0=B;

[0065] The relative check value C is a calibration constant, C=BA=(Z1+Z0)-(Z2 + H).

[0066] During placement, the height is dynamically controlled in real time. In actual placement, the laser probe obtains real-time Z2' and H' on the surface of the object to be placed. Substitute these values ​​into the calibration relationship: Z1 + Z0′ = C + Z2′ + H′, to verify the placement height Z0′ of the placement head. The target placement height Z0′ is set according to the product design specifications, and precise positioning is achieved by adjusting the Z-axis coordinate of the robotic arm.

[0067] Specifically, taking the tilted mounting of semiconductor chips as an example: during the calibration phase, C=0.15mm was measured, and the designed mounting height Z0′=1.20mm; during mounting, the laser feedback Z2′=50.10mm and H′=0.95mm, and the calculation yields: Z1=0.15+50.10+0.95-1.20=50.00mm; after the robotic arm descends to Z=50.00mm, it performs horizontal embedding and upright mounting without edge contact.

[0068] In this embodiment, the mounting equipment includes a robotic arm, and the mounting head is disposed at the working end of the robotic arm.

[0069] Specifically, the robotic arm drives the mounting head to pick up the mounting body, first rotating the mounting body to the designed angle, then positioning it in the Z direction, and then horizontally embedding it.

[0070] Specifically, the rotation correction angle range is 0-90°, and the angular resolution is not less than 0.1°.

[0071] In this embodiment, the mounting head is provided with an anti-collision buffer during the horizontal movement phase, and stops moving when the distance between the mounting body and the groove edge of the object to be mounted is less than the anti-collision buffer.

[0072] Specifically, the anti-collision buffer zone is 0.1mm, and the movement automatically stops when the distance between the mounting body and the groove edge of the object being mounted is less than 0.1mm; the Z-axis position locking accuracy of the mounting body during the horizontal movement phase needs to be maintained within ±0.02mm.

[0073] In this embodiment, the Z-axis correction sensor is a contact trigger sensor.

[0074] Specifically, the perpendicularity error between the installation position of the Z-axis correction sensor and the measured surface does not exceed ±0.1°, which is used to record the precise trigger position during the descent of the robotic arm.

[0075] In this embodiment, the laser is a point laser rangefinder.

[0076] Specifically, the laser measurement accuracy needs to reach ±0.01mm, the sampling frequency is not less than 1kHz, and it is used to non-contactly measure the height of the surface of the object being attached. The laser data is then fused with the data from the Z-axis sensor for calculation. The sensor is automatically calibrated when the device is started, and the calibration data is stored in a non-volatile memory.

[0077] In this embodiment, the calibration parameter C is obtained through a single calibration during the device initialization phase and participates in real-time calculation as a constant value during the mounting process.

[0078] Specifically, the mounting equipment includes a multi-axis motion controller, a sensor data acquisition card, and a real-time computing processor. The real-time computing processor adopts an FPGA architecture, with a calculation delay of no more than 1ms, and is used to perform calibration parameter calculation and dynamic compensation of mounting height.

[0079] The tilt mounting Z-axis height control method described in this embodiment avoids structural interference with the groove edge of the mounted object during lateral movement in tilt mounting by calibrating parameter C and real-time compensation, and eliminates the influence of mechanical errors and environmental fluctuations on the Z-axis height, thereby improving accuracy. It is applicable to mounted objects with different curved surfaces and tilt angles, is compatible with various mounting processes, and has strong adaptability.

[0080] It should be noted that the above-mentioned technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this invention specification; and, for those skilled in the art, improvements or modifications can be made based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for controlling the Z-axis height during tilted mounting, used to correct the height of a product during tilted mounting, characterized in that: The method for controlling the Z-axis height of tilted placement includes the following steps: (The method includes a placement device, which includes a placement head.) Step S1: Move the placement head above the Z-axis correction sensor, obtain the placement head coordinate values, and set the initial height based on the current placement head coordinate values; Step S2: Move the placement head down so that it touches the Z-axis correction sensor, record the Z-axis coordinate when it touches the Z-axis correction sensor, and set the mating height between the current placement head and the Z-axis correction sensor; Step S3: Move the laser set on the side of the placement head above the Z-axis correction sensor, obtain the coordinate value and numerical value of the laser, and calculate the coordinate value and numerical value of the laser to obtain the first fixed value; Step S4: Calculate the mating height between the placement head and the Z-axis correction sensor, and the Z-axis coordinate of the placement head to obtain a second fixed value; then correct it with the first fixed value to obtain the relative verification value between the placement head and the Z-axis correction sensor, and verify the new mating height between the placement head and the Z-axis correction sensor based on the coordinate value and numerical value of the laser. Step S1 includes the following steps: Step S11: Set calibration points on the Z-axis calibration sensor; Step S12: Move the placement head above the Z-axis correction sensor and record the current placement head coordinate value Z; Step S13: Set the initial height z using the mounting head coordinate value Z; Step S3 includes the following steps: Step S31: Switch to laser, move the laser cursor to the center position of the Z-axis correction sensor, and record the current laser coordinate value Z2 and value H; Step S32: Calculate the coordinate value Z2 and the numerical value H of the laser to obtain the first fixed value A, Z2+H=A.

2. The tilt-to-stick Z-height management method of claim 1, wherein, In step S2, when the placement head touches the Z-axis correction sensor, the Z-axis coordinate Z1 of the placement head touching the Z-axis correction sensor is recorded, and the mating height Z0 between the placement head and the Z-axis correction sensor is 0.

3. The method for controlling the Z-axis height of tilted mounting according to claim 1, characterized in that, Step S4 includes the following steps: Step S41: Calculate the second fixed value B based on the mating height between the placement head and the Z-axis correction sensor, and the Z-axis coordinate of the placement head, Z1+Z0=B; Step S42, calculate the relative check value C = BA = (Z1 + Z0) - (Z2 + H); Step S43: During mounting, the laser acquires the coordinate values ​​Z2′ and H′ in real time; Step S44, substitute the calibration relationship: Z1+Z0′=C+Z2′+H′, to verify the placement height Z0′ of the placement head.

4. The tilt mounting Z-axis height control method according to claim 3, characterized in that, In step S4, the compensation formula for the actual mounting height Z0′ of the mounting head is: ΔZ=(C+Z2′+H′)-(Z1+Z0′).

5. The method for controlling the Z-axis height of tilted mounting according to claim 1, characterized in that, The mounting equipment includes a robotic arm, and the mounting head is disposed at the working end of the robotic arm.

6. The method for controlling the Z-axis height of inclined mounting according to claim 5, characterized in that, The mounting head is equipped with an anti-collision buffer during the horizontal movement phase. The movement stops when the distance between the mounting body and the groove edge of the object to be mounted is less than the anti-collision buffer.

7. The method for controlling the Z-axis height of tilted mounting according to claim 5, characterized in that, The Z-axis correction sensor is a contact-triggered sensor.

8. The method for controlling the Z-axis height of inclined mounting according to claim 5, characterized in that, The laser is a point laser rangefinder.

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