TWI525737B - Method and apparatus for picking and placing chip dies with high aspect ratio - Google Patents

Description

Grain picking device and method capable of picking high aspect ratio die

The present invention relates to a grain picking device and method, and more particularly to a die picking device and method for picking high aspect ratio grains.

In general, after the integrated circuit (IC) is designed, synthesized, laid out, and then fabricated, all the wafer dies are regularly distributed on a wafer like a matrix. Although some basic wafer functional tests are performed via the On Wafer Test, electrical characteristics and wafer performance testing must still be performed after Die Saw via Chip Holder (Chip Tray). Shipped to the test machine for testing, and the movement of the die between the die carrier and the test machine must be done via the Pick & Place. Similarly, the process of moving the die from the wafer frame to the die carrier or from the die carrier to the wafer frame is also accomplished through the die picker.

Common wafers such as SOC (System on Chip) or ASIC (Application Specific Integrated Circuit), etc., for the optimization of area and the consideration of the shortest winding, the die is designed to be as close as possible to the square shape, that is, The aspect ratio of the grains is about 1. Please refer to FIG. 1. FIG. 1 is a schematic diagram of a die picking head 108 picking up a die 102 by a conventional die picking device. For simplicity of illustration, the illustration of the die picking device only depicts the position of the die picker. As shown in Fig. 1, since the aspect ratio of the crystal grain 102 is about 1, if the crystal grain 102 is slightly shifted in the X direction, the Y direction, or the relative rotation angle (Theta angle) between the crystal grain and the suction head, the crystal Pellet picker 108 When the die 102 is sucked, it can still overlap with the die 102 in a large area. Therefore, in the die picking process, the precision requirement for the die picking machine is not too high. As shown in FIG. 2, the crystal grains are arranged on the die carrier 200 in a regular manner, and the die picking head 208 only needs to set the first die in the lower left corner as the positioning point 217, after the alignment is performed. The distance between the die 202 input by the user, the center point 207 of the die pick-up head 208 can be picked up on the die 202 for all grains in a grain-by-grain manner or in a specified grain.

However, high aspect ratio grains will encounter difficulties in alignment, suction, and placement during the picking process, thus causing reliability problems. For example, the driver IC (Chip IC) may have a grain aspect ratio greater than 10, and the die picker has only one die pick-up head, so there may be insufficient suction and drop, or the positioning is inaccurate and the center of gravity Offset, even because of the offset of the angle between the die carrier and the die picker, there will be a large deviation from the alignment, suction, placement, etc. in the die picking process, resulting in the die not being able to Being effectively picked up.

Therefore, how to develop a grain picking method and a grain picking device that can pick up high aspect ratio grains is one of the important topics in the field.

One of the objects of the present invention is to provide a die picking apparatus and method which utilizes a die picking machine having a plurality of vacuum die picking heads and solves the problem that the conventional die picking machine cannot accurately or efficiently pick high aspect ratio crystals. Granule problem.

The invention discloses a method for picking up dies, which is used to pick up and place a plurality of dies placed on a chip carrier (Phip Tray) from the wafer carrier tray and place them into a wafer pick-up tray (Pick and Place). On the wafer frame (Wafer Frame). The method includes setting a size of the wafer carrier and setting an arrangement position or spacing of the plurality of crystal grains; moving one of the picking arms of the die picking device to make two vacuum die suction heads on the picking arm (vacuum chuck) One of them The center point is overlapped with a first positioning point of the wafer carrier, and a first coordinate value of the first positioning point relative to the die picking device is calculated; and the picking arm of the die picking device is moved to make the Locating the center point of the two vacuum die suction heads on the picking arm with a second positioning point of one of the wafer carrier disks, and calculating a first rotation angle of the wafer carrier disk relative to the die picking device; a first index value, the first rotation angle, a size of the wafer carrier, and an arrangement position or spacing of the plurality of crystal grains, and moving the two vacuum die suction heads on the pick arm to a crystal in the plurality of crystal grains Granules to absorb the grains.

The invention further discloses a die picking device capable of picking up high aspect ratio dies for picking and placing a plurality of dies placed on a wafer carrier disk into a wafer frame ( Wafer Frame). The die picking device includes a setting module for setting a size of a wafer carrier, and for setting an arrangement position or spacing of the plurality of crystal grains; and a pair of bit modules for moving the die picking device a picking arm, wherein a center point of one of the vacuum chucks on the picking arm is overlapped with a first positioning point of the one of the wafer carrying trays to calculate the first positioning point relative to the die a first coordinate value of one of the picking devices, and the picking arm for moving the die picking device, such that the center point of the two vacuum die picking heads on the picking arm overlaps with a second positioning point of the one of the wafer carrying trays Aligning to calculate a first rotation angle of the wafer carrier relative to the die picking device; and a die picking module for: according to the first coordinate value, the first rotation angle, the wafer carrier The size and the arrangement position or spacing of the plurality of crystal grains move the two vacuum die suction heads on the pick arm to a die of the plurality of crystal grains to absorb the crystal grains.

102, 202, 402, 502, 602‧‧ ‧ grains

602’‧‧‧Ideal grain position

108, 208‧‧‧ die picking head

408, 418, 508, 518, 608, 618‧‧‧ vacuum die suction head

200, 500, 700‧‧‧ wafer carrier

217, 517, 717, 737‧‧ ‧ anchor points

207, 507, 607, 707 ‧ ‧ central point

Θ‧‧‧ angle

30‧‧‧Process

300~310‧‧‧Steps

90‧‧‧Grad picking device

900‧‧‧Loading tray carrier

902‧‧‧Setting module

904‧‧‧Image capture module

906‧‧‧ alignment module

908‧‧‧Grad suction module

Figure 1 is a schematic diagram of a grain picking head picking up a die from a conventional grain picking device.

Figure 2 is a top view of the die pick-up head of Figure 1 operating on a wafer carrier.

FIG. 3 is a schematic diagram of a die picking process according to an embodiment of the present invention.

4 is a partial schematic view of a vacuum die pick-up head of a die and die picking device according to an embodiment of the present invention.

Figure 5 is a top view of a vacuum die pick-up head operating on a wafer carrier tray in accordance with an embodiment of the present invention.

Figure 6 is a top view of a die taken by a vacuum die pick-up head according to an embodiment of the present invention.

Figure 7 illustrates a schematic diagram when there is an angular error between the wafer carrier and the die picking device.

Figure 8 is a schematic diagram of the alignment of the wafer carrier of Figure 7 using two positioning points.

Figure 9 is a schematic view of a die picking device according to an embodiment of the present invention.

Please refer to FIG. 3, which is a schematic diagram of a die picking process 30 according to an embodiment of the present invention. The die picking process 30 is for picking up a plurality of dies placed on a chip carrier (Phip Tray) from the wafer carrier by a wafer picker and placing it on a wafer frame ( Wafer Frame). The die picking process 30 can be applied to dies having a high aspect ratio and can be efficiently picked for a driver IC having an aspect ratio greater than 10. The grain picking process 30 includes the following steps:

Step 300: Start.

Step 302: Set the size of the wafer carrier and set the arrangement position or spacing of the plurality of crystal grains.

Step 304: Moving one of the picking arms of the die picking device, so that a center point of one of the vacuum chucks on the picking arm overlaps with a first positioning point of one of the wafer carrying trays, and calculates the The first anchor point is relative to one of the first coordinate values of the die picking device.

Step 306: Move the picking arm of the die picking device to overlap the center point of the two vacuum die picking heads on the picking arm with a second positioning point of the wafer carrier, and calculate the relative position of the wafer carrier One of the first rotation angles of the die picking device.

Step 308: According to the first coordinate value, the first rotation angle, the size of the wafer carrier, and the arrangement position or spacing of the plurality of crystal grains, the two vacuum die suction heads on the picking arm are Moving to a die of the plurality of grains to pick up the die.

Step 310: End.

According to the die picking process 30, the die picking device is first initialized. The initial setting may include setting the size of the wafer carrier and setting the arrangement position and spacing of the plurality of crystal grains. Then, according to the user setting, one of the picking arms of the die picking device is moved to move a center point of the two vacuum die suction heads on the picking arm to a preset first positioning point coordinate of one of the wafer carrier disks, and then The image capturing device is used to correct until the center point is completely overlapped with the first positioning point of one of the wafer carrier disks, and the first coordinate value of the first positioning point relative to the die picking device is calculated. In addition, according to the user setting and the correction of the image capturing device, the picking arm of the die picking device is moved so that the center point of the two vacuum die picking heads on the picking arm overlaps with the second positioning point of one of the wafer carrier disks Align and calculate a first angle of rotation of the wafer carrier relative to one of the die picking devices. Then, according to the first coordinate value, the first rotation angle, the size of the wafer carrier, and the arrangement position or spacing of the plurality of crystal grains, the actual position of the die is obtained, and accordingly, the vacuum is applied to the picking arm. The die picking head is moved to the die to be picked, and the angles of the two vacuum die picking heads are appropriately adjusted to pick up the die. Through the operation of the grain picking process 30, the actual value of the relative rotation angle (Theta angle) of the grain in the X direction, the Y direction or the die and the suction head can be known to correct the two vacuum die suction on the picking arm. The position and angle of the head allows the selection of high aspect ratio grains.

For details, please refer to FIG. 4, which is a partial schematic view of a vacuum die pick-up head 408, 418 of a die 402 and a die picking device according to an embodiment of the present invention. For the sake of simplicity of the illustration, Figure 4 only depicts the position of the die pick-up head of the die picking device. The picking arm of the die picking device can be equipped with two or more vacuum die picking heads 408, 418 for drawing both sides of the high aspect ratio die 402. The die picking device further includes an image capturing device for amplifying and capturing images of the die to fine tune the position of the picking arm. Please refer to FIG. 5. FIG. 5 is a top view of the vacuum die pick-up heads 508, 518 operating on a wafer carrier disk 500 according to an embodiment of the present invention. The grain picking device is first based on Presetting the position of the die and the positioning point, moving one of the picking arms of the die picking device, moving the center point 507 of one of the two vacuum die picking heads 508, 518 on the picking arm to a preset one of the wafer carrying trays The first positioning point 517 coordinates, and then is corrected by the image capturing device until the center point is completely overlapped with the first positioning point 517, and the first coordinate value of the first positioning point 517 relative to the die picking device is calculated (eg In the ideal case, the first coordinate value is (a/2, b/2), where a and b are the width and length of the die 502, respectively. If the angle between the wafer carrier and the die picking device is zero, that is, there is no error, then the die picking device only needs to pick or pick one by one according to the size of the wafer carrier and the arrangement position and spacing of the die. Specified grain.

However, due to the limitation of accuracy, the angle between the wafer carrier and the die picking device Theta may not be zero. As shown in Fig. 6, the dotted line 602' indicates the original ideal grain position, and the solid line 602 indicates the actual position of the crystal grain when there is an angular error, and there is an error angle Theta(θ) between the two. It can be seen from Fig. 6 that if a conventional single vacuum suction head is used to pick a high aspect ratio grain, there is a possibility that the center of gravity imbalance may not be picked or picked. However, if the two vacuum die picking heads 608, 618 are used to pick up the die 602, although the center points 607 of the two vacuum die picking heads 608, 618 have deviated from the die, there is still a greater chance of picking. It can be seen that the high aspect ratio grains have higher requirements for positioning accuracy.

Further, Fig. 7 illustrates the effect on picking when there is an error in the angle θ between the wafer carrier disk 700 and the die picking device. In Fig. 7, 717 represents the position of the first positioning point, and 707 of the shape of the dot represents the center point of the grain picking position obtained by the grain picking device after the alignment calculation. The center point 707 of the die picking position is calculated based on the first coordinate value calculated by the first positioning point 717, the size of the set wafer carrier 700, and the arrangement position or spacing of the crystal grains. It can be seen from Fig. 7 that the position error is greatly enlarged in the area away from the first positioning point 717, thereby causing the probability of picking failure. In order to minimize the angular error, a second positioning point 737 can be added to the wafer carrier, as shown in FIG. At the first positioning point 717 After positioning and recording the coordinates, similarly, one of the picking arms of the die picking device is moved so that the center point of the two vacuum die picking heads on the picking arm overlaps with the second positioning point 737 of the wafer carrier 700, and is calculated. The second positioning point 737 is rotated by an angle θ with respect to one of the wafer carrier devices relative to the wafer carrier 700 relative to the coordinate value of the die picking device. In this way, each die can be aligned and a pair of bit results can be generated to provide accurate grain coordinates of the die picking device to accurately pick up each die.

It should be noted that the present invention aligns and aligns the high aspect ratio dies with the first and second locating points respectively located at opposite corners of the wafer carrier to facilitate the two vacuum dies. Accurately draw each die. Those skilled in the art will be able to make various modifications, and are not limited thereto. For example, a rotating member may be disposed on the picking arm of the die picking device, so that the angle between the connection of the two vacuum die picking heads and the body of the die picking device can be adjusted to correct the rotation angle of the wafer carrier. In addition, the two vacuum die suction heads on the picking arm can share the same vacuum suction pump, but are not limited thereto. In another embodiment, the two vacuum die suction heads on the picking arm can be connected to two separate vacuum suction pumps, respectively.

The image picking device may use an image capturing module (for example, an amplifying device plus a camera) to capture a first image including one of the first positioning points, and the camera may adopt a resolution of a higher magnification to clearly capture one All images of high aspect ratio grains. The first image can be transmitted to a processing module, and the image of the die is analyzed by image recognition technology to calculate a first coordinate value of the first positioning point relative to the die picking device. Similarly, the image capturing module can also be used to capture a second image including a second positioning point, and transmit the second image to the processing module, and analyze the image of the die through image recognition technology to calculate the wafer bearing. The first angle of rotation of the disk relative to the die picking device.

The die picking device can place the sucked die in the wafer frame to facilitate subsequent use of the test machine for die electrical characteristics and wafer performance testing. Similarly, the wafer frame can be phased first. The two corners of the pair respectively have a third positioning point and a fourth positioning point for correcting a second coordinate value and a second rotation angle between the wafer frame and the two vacuum die suction heads on the picking arm. . The process of die placement is similar to the grain picking process. The main difference is that one picks up the die after the correct position and angle, and the other is the grain after the correct position and angle. lay down. Therefore, the detailed process will not be described again.

Please refer to FIG. 9. FIG. 9 is a schematic diagram of a die picking device 90 according to an embodiment of the present invention. The die picking device 90 can be used to pick up the grains within the wafer carrier disk 700 as shown in FIG. The die picking device 90 includes a carrier carrier (Tray Loader) 900, a setting module 902, an image capturing module 904, a pair of bit modules 906, and a die picking module 908. The carrier tray carrier 900 is used to carry the wafer carrier tray 700. The setting module 902 is used to set the size of the wafer carrier 700 and to set the arrangement position or spacing of the plurality of dies 702. The image capturing module 904 is configured to capture a first image including a first positioning point 717. The alignment module 906 is configured to move one of the picking arms of the grain picking device 90 to enable the two vacuum die suction heads on the picking arm. The center point is overlapped with the first anchor point 717 of the wafer carrier disk 700 to calculate a first coordinate value of the first anchor point 717 relative to the die picking device 90. The image capturing module 904 is further configured to capture the second image including the second positioning point 737, and move the picking arm of the grain picking device 90 through the matching module 906 to make the two vacuum die suction heads on the picking arm The center point is overlapped with the second locating point 737 of the wafer carrier disk 700 to calculate a first rotational angle θ of the wafer carrier disk 700 relative to the die picking device 90. The die picking module 908 is configured to move the two vacuum die suction heads on the picking arm to the first coordinate value, the first rotation angle θ, the size of the wafer carrier 700, and the arrangement position or spacing of the plurality of crystal grains 702. A plurality of crystal grains 702 are on one of the crystal grains to absorb the crystal grains. In addition, the design details of other parts of the grain picking device 90 are not different from the conventional die picking machine, and therefore will not be described in detail herein.

In addition, the above embodiment is described in which the die is picked up from the wafer carrier and placed on the wafer frame, wherein the wafer carrier has a plurality of matrix-type grooves for carrying the cutting. The plurality of grains are followed by, but are not limited thereto. The above described processes and embodiments can also be applied to picking and placing a die from a wafer frame onto another wafer frame, or picking the die from a wafer frame and placing it on a wafer carrier.

In summary, the die picking process and the grain picking device of the present invention can be used to pick up high aspect ratio grains, and use a plurality of vacuum die picking heads on the picking arm to absorb long strips having an aspect ratio of substantially 2 or more. Both sides of the grain. And correcting a coordinate position and a rotation angle error between the wafer carrier disk and the die pick-up head module in the die picking device by using the first positioning point and the second positioning point on the wafer carrier in the process of alignment Accurately and efficiently pick or place high aspect ratio grains.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

30‧‧‧Process

300~310‧‧‧Steps

Claims (16)

A method of picking up dies for picking up a plurality of dies placed on a wafer carrier from a wafer carrier and picking them into a wafer frame using a die pick and place (Pick and Place) (Wafer Frame), the method comprises: setting a size of the wafer carrier, and setting an arrangement position or a spacing of the plurality of crystal grains; moving a picking arm of the die picking device to make two vacuums on the picking arm A center point of a vacuum chuck is overlapped with a first positioning point of the wafer carrier, and a first coordinate value of the first positioning point relative to the die picking device is calculated; and the crystal is moved The picking arm of the particle picking device is configured such that the center point of the two vacuum die picking heads on the picking arm overlaps with a second positioning point of the one of the wafer carrying trays, and the wafer carrying tray is calculated relative to the die picking device a first rotation angle; and two vacuum die suction heads on the pick arm according to the first coordinate value, the first rotation angle, the size of the wafer carrier, and the arrangement position or spacing of the plurality of crystal grains mobile The plurality of grains on a die, to draw the die. The method of claim 1, wherein the first positioning point and the second positioning point are respectively located at opposite corners of the wafer carrier. The method of claim 1, wherein the wafer carrier has a plurality of matrix-arranged grooves for carrying the plurality of diced grains after cutting. The method of claim 1, wherein the image picking device uses an image capturing module to capture a first image including the first positioning point to calculate the first positioning point relative to the die picking device. The first coordinate value is used, and the second image of the second positioning point is captured by the image capturing module to calculate the first rotation angle of the wafer carrier relative to the die picking device. The method of claim 1, wherein the wafer frame is used to place the plurality of dies for testing by a test machine, and the opposite corners of the wafer frame respectively have a third positioning point and a first The four positioning points are used to correct an error between a second coordinate value and a second rotation angle between the wafer frame and the two vacuum die suction heads on the picking arm. The method of claim 1, wherein the two vacuum die suction heads on the picking arm share the same vacuum pumping pump. The method of claim 1, wherein the two vacuum die suction heads on the picking arm are respectively connected to two independent vacuum suction pumps. The method of claim 1, wherein the two vacuum die suction heads on the picking arm are configured to absorb both sides of the elongated strips having an aspect ratio substantially equal to or greater than two. A die picking device for picking high aspect ratio dies for picking up a plurality of dies placed on a wafer carrier from a wafer carrier and placing them on a wafer frame The die picking device includes: a setting module for setting a size of a wafer carrier, and a setting position or spacing of the plurality of crystal grains; and a pair of bit modules for moving the die Picking arm of one of the picking devices, such that a center point of one of the vacuum chucks on the picking arm overlaps with a first positioning point of one of the wafer carrying trays to calculate the first positioning point relative to the a first coordinate value of one of the die picking devices, and the picking arm for moving the die picking device, such that the center point of the two vacuum die picking heads on the picking arm and the second positioning of the one of the wafer carrying trays Point overlap alignment to calculate the first spin of the wafer carrier relative to one of the die picking devices And a die picking module for locating the picking arm according to the first coordinate value, the first rotation angle, the size of the wafer carrier, and the arrangement position or spacing of the plurality of crystal grains The vacuum die picking head moves onto a die of the plurality of grains to pick up the die. The die picking device of claim 9, wherein the first positioning point and the second positioning point are respectively located at opposite corners of the wafer carrier. The die picking device of claim 9, wherein the wafer carrier has a plurality of matrix-arranged grooves for carrying the plurality of die after cutting. The image picking device of claim 9, further comprising an image capturing module for capturing a first image including the first positioning point to calculate the first positioning point relative to the die picking The first coordinate value of the device and the second image for capturing the second positioning point to calculate the first rotation angle of the wafer carrier relative to the die picking device. The chip picking device of claim 9, wherein the wafer frame is used to place the plurality of crystal grains for testing by a test machine, and the opposite corners of the wafer frame respectively have a third positioning point And a fourth positioning point for correcting a second coordinate value and a second rotation angle between the wafer frame and the two vacuum die suction heads on the picking arm. The die picking device of claim 9, wherein the two vacuum die suction heads on the picking arm share the same vacuum suction pump. The die picking device of claim 9, wherein the two vacuum die suction heads on the picking arm are respectively connected to two independent vacuum suction pumps. The die picking device of claim 9, wherein the two vacuum die suction heads on the picking arm are configured to absorb both sides of the elongated strips having an aspect ratio substantially equal to or greater than two.