KR100351388B1 - Inspection apparatus of encapsulation height and warp of BGA type semiconductor device package - Google Patents

Abstract

The present invention allows the laser beam generator and the line scan camera to move in the XY axis and up and down with one jig, and install a mirror at a predetermined angle under each of them, and the laser beam irradiated and reflected on the inspection object through the mirror is provided. An encapsulation height and fin inspection apparatus of a BGA semiconductor package for which a line scan camera is photographed.

According to the present invention, a laser beam is irradiated to a portion in which the semiconductor chip is molded in the vertical direction of the semiconductor package 10, and the laser beam is reflected from the molded portion of the semiconductor chip and is incident to another position according to the height. Shooting unit 20 for outputting; A microcomputer (31) which receives the photographing data output from the photographing unit, calculates the real height of the part where the semiconductor chip is molded, and compares it with reference data to determine whether the defect is defective; First and second motors 32 and 33 for moving the photographing unit to the XY axis; A motor driver 34 driving the first and second motors under the control of the microcomputer; A memory unit 35 for storing a program and reference data for an operation of the microcomputer and providing the reference data according to the request of the microcomputer; And a monitor 36 for outputting a photographing result under the control of the microcomputer 31.

Description

Inspection apparatus of encapsulation height and warp of BGA type semiconductor device package

The present invention relates to an apparatus for inspecting a ball grid array (BGA) semiconductor package using a laser beam generator and a line scan camera. In particular, the present invention enables a laser beam generator and a line scan camera to be moved in an XY axis with a single jig. A mirror is installed at a lower part of each of them to allow the line scan camera to photograph the laser beam reflected and reflected through the object, thereby inspecting the encapsulation height of the super BGA semiconductor package and the height of the BGA. An encapsulation height and fin inspection apparatus of a BGA semiconductor package.

In recent years, with the trend of miniaturization of electronic products, the size and thickness of semiconductor packages mounted on substrates are gradually decreasing. Since such a small semiconductor device is deformed by slight defects generated during the manufacturing process, a high degree of precision is required in the manufacturing process, and a large defect rate must be taken. Accordingly, semiconductor device manufacturers have introduced various types of inspection apparatuses to quickly and accurately produce high quality small size semiconductor devices while minimizing defect rates, thereby inspecting defects of semiconductor packages during the manufacturing process, thereby screening or preventing defective products.

A general manufacturing process of the BGA semiconductor package and the super BGA semiconductor package, which is one type of semiconductor package, is as follows.

The BGA semiconductor package attaches a semiconductor chip having a plurality of bonding pads to a depression of a plate-shaped plate with a pattern film providing an electrical signal transmission path, and uses a wire between the bonding pad and the pattern film of the semiconductor chip. After the electrical connection, the semiconductor chip and the upper region of the wire-bonded pattern film are sealed with a mold resin, and a plurality of flux grids are used on a ball grid provided to exchange electrical signals with the outside on the lower surface of the pattern film. It is manufactured by welding solder balls.

In addition, the super BGA semiconductor package attaches a semiconductor chip having a plurality of bonding pads to a depression of a plate-shaped plate attached with a pattern film that provides an electrical signal transmission path, and wires between the bonding pad and the pattern film of the semiconductor chip. After the electrical connection by using a semiconductor chip and the upper region of the wire-bonded pattern film is applied using a dispenser filled with a liquid top (Glob Top), the outside on the outside of the semiconductor chip It is manufactured through the process of fusion bonding a plurality of balls using a flux to a ball grid provided to exchange electrical signals with.

The BGA and the super BGA semiconductor package as described above is mainly a defect in the solder ball fusion process, but also a lot of defects in the process of molding or dispensing to protect the semiconductor chip and the pattern film from the outside.

6A is a side view of a normal super BGA semiconductor package.

The figure shows that the height of the encapsulation 11 on the circuit board 13 is lower than the height of the solder ball 12. As described above, the super BGA has the height of the encapsulation 11 so that the solder ball 12 contacts the external terminal because the solder ball 12 is fused to the upper surface of the circuit board 13 in the same manner as the encapsulation 11. It should be lower than the height of the solder ball (12).

FIG. 6B is a side view of an abnormal super BGA semiconductor package, showing a state in which the height of the encapsulation 11 is applied higher than the height of the solder ball 12.

Such abnormal encapsulation 11 is a major factor preventing the solder ball 12 from contacting the external terminal.

FIG. 7A is a side view of a normal BGA semiconductor package, showing that the mold resin 14 and the circuit board 13 have a flat shape.

7B and 7C are side views of an abnormal BGA semiconductor package, in which the mold resin 14 and the circuit board 13 are moved upward or downward due to a difference in coefficient of thermal expansion with the circuit board 13 during curing of the mold resin 14. ) Shows that a warp has occurred.

Such spalling is also a major obstacle that prevents solder balls from contacting external terminals, such as the abnormal encapsulation height described above.

As described above, the abnormal encapsulation of the super BGA semiconductor package generated in the molding process of the semiconductor package and the mold resin of the BGA semiconductor package and the shortness of the circuit board are a great bad factor of the semiconductor device. The device is desperately needed.

Conventional inspection apparatus for inspecting the defect of the semiconductor package is made by using a plurality of cameras to shoot the appearance and to check whether the defect is observed in the video image, such as abnormal encapsulation height and 웝 of the BGA semiconductor package Defect was not able to accurately determine, there was a problem that the size of the inspection equipment is large due to the use of a plurality of cameras.

An object of the present invention for solving the above problems is to enable the laser beam generator and the line scan camera to move in the XY axis with one jig and to install a mirror at a certain angle under each of them and irradiate the inspected object through the mirror. By allowing the line-scan camera to capture the reflected laser beam, it is possible to accurately inspect the encapsulation height and the BGA deflection of the super BGA semiconductor package and to simplify the scale of the inspection equipment. To provide a device.

1 is a block diagram of an encapsulation height and fin inspection apparatus of a BGA semiconductor package according to the present invention;

2 is a flow chart showing an operation process of the inspection apparatus according to the present invention;

3 is a detailed perspective view illustrating the photographing unit of FIG. 1;

FIG. 4 is a view illustrating a path of a laser beam incident to a line scan camera of FIG. 3 at different positions according to a height of a semiconductor package;

5a and 5b is a view showing an embodiment of the shooting path by the apparatus of the present invention,

6A is a side view of a normal super BGA semiconductor package,

6B is a side view of an abnormal super BGA semiconductor package,

7A is a side view of a normal BGA semiconductor package,

7B and 7C are side views of an abnormal BGA semiconductor package.

<Description of the symbols for the main parts of the drawings>

10 semiconductor package 11 encapsulation

12 solder ball 13 circuit board

14: mold resin 20: the photographing unit

21: laser beam generator 22: line scan camera

23: first mirror 24: second mirror

31: micom 32: the first motor

33: second motor 34: motor drive unit

35: memory 36: monitor

37: interface device 38: control computer

41: X axis moving table 42: X axis moving port

43: X axis shaft 44: X axis lead screw

51: Y axis moving table 52: Y axis moving port

53: Y axis shaft 54: Y axis lead screw

In order to achieve the above object, the present invention is to irradiate a laser beam to the molded portion of the semiconductor chip in the vertical direction of the semiconductor package and to photograph the laser beam is reflected from the molded portion of the semiconductor chip is incident to different positions according to the height A photographing unit which outputs the photographing data; A microcomputer that receives the photographing data output from the photographing unit, calculates a real height of a part in which the semiconductor chip is molded, and compares it with reference data to determine whether the defect is defective; First and second motors for moving the photographing unit to the XY axis; A motor driver configured to drive the first and second motors under the control of the microcomputer; A memory unit for storing a program and reference data for the operation of the microcomputer and providing the reference data according to the request of the microcomputer; And a monitor configured to output a photographing result under the control of the microcomputer.

Hereinafter, with reference to the accompanying drawings will be described the present invention in more detail.

1 is a block diagram of an encapsulation height and chip inspection apparatus of a BGA semiconductor package according to the present invention.

As shown in the drawing, the microcomputer 31 which controls the operation of the inspection apparatus as a whole and compares the photographing data value with the reference data value is installed perpendicular to the semiconductor package 10 to control the microcomputer. Accordingly, the photographing unit 20 photographing the semiconductor package 10 and transmitting the photographing data to the microcomputer, and the first and second motors 32 for moving the position of the photographing unit 20 to the X-axis or the Y-axis. , 33), the motor driver 34 for driving the first and second motors 32 and 33 under the control of the microcomputer, the height data and the reference data of the incident position of the program and the line scan camera for the microcomputer operation. The memory unit 35 stores values and provides them according to the request of the microcomputer, a monitor 36 for outputting measurement results according to the control of the microcomputer, and communicates with the microcomputer through an interface device 37 to control the program. Transmitting the ram or is a control computer (38) for receiving inspection result data from the microcomputer is connected.

In the above, the photographing unit 20 generates a laser beam under the control of the microcomputer and irradiates the semiconductor package 10, and a line scan for photographing the laser beam reflected from the semiconductor package 10. A first mirror 23 installed at a predetermined angle under the camera 22, the laser beam generator 21, and the line scan camera 22 to refract the laser beam of the laser beam generator to be irradiated onto the semiconductor package; A second mirror 24 is further provided to refracting the laser beam reflected from the semiconductor package to be incident to the line scan camera 22 side.

Referring to the flowchart of FIG. 2, the operation of the encapsulation height and the 웝 test apparatus of the BGA semiconductor package configured as described above is as follows.

First, the microcomputer 31 determines a photographing range setting step of checking whether the photographing start region and the photographing path selection region for each of the semiconductor packages are set by the control computer 38 connected by the interface device 37. If the photographing range is set by performing a photographing start signal is input from the control computer 38 performs a photographing unit position determination step of checking whether or not the photographing unit 20 is in the photographing start position.

In the photographing unit position determining step, when the photographing unit 20 is not at the photographing start position, the microcomputer controls the motor driver 34 to move the photographing unit 20 to the photographing start position so that the first and second motors ( 32, 33, and when the photographing unit 20 is in the photographing start position, the microcomputer controls the photographing unit 20 and the motor driving unit 34 to photograph the preset selection area for each photographing path. The photographing data is received from the photographing unit 20.

Thereafter, when the photographing of the semiconductor package by the photographing unit 20 is completed, the real height is calculated from the height data for each incident position stored in the memory unit 35 from the photographing data value, and then the photographing data value is the reference data. A comparison step of determining whether or not the value is the same is performed, and when the photographing data value is the same as the reference data value, the real height is output through the monitor 16 and the genuine product is displayed.

When the photographing data value is not the same as the reference data value in the comparing step, the calculated height is output to the monitor 16 and the defective product is displayed to complete the inspection of one semiconductor package.

After that, it is checked whether or not the next inspection target exists and, if there is no check, the inspection operation is terminated. If there is a signal input by performing the determination of resetting the shooting range is checked to reset the shooting area according to the input shooting range and return to the shooting position determination step, if there is no signal input to the previously set shooting range Accordingly, the process returns to the photographing unit position determining step to repeatedly inspect the next semiconductor package.

3 is a detailed perspective view illustrating the photographing unit of FIG. 1.

As referred to in the drawings, the photographing unit 20 is a laser beam generator 21 and the line scan camera 22 and the semiconductor package by refracting the laser beam is installed at a predetermined angle on the lower side of the laser beam generator 21 The first mirror 23 irradiated by the encapsulation 11 of the laser beam and the laser beam reflected from the encapsulation 11 are refracted by the first mirror 23 and the line scan camera 22 at a predetermined angle. The second mirror 24 to be incident to the camera 22 is integrally formed, and the integrally configured photographing unit 20 is coupled to the X-axis moving hole 42, and the X-axis moving hole 42 is connected to the X axis. As the X-axis lead screw 44 is rotated by the rotation of the first motor 31 by combining with the shaft 43 and the X-axis lead screw 44, the X-axis moving hole 42 is the X-axis moving table 41 Install to move along

In addition, the X-axis moving table 51 is coupled to the Y-axis moving port 52, and the Y-axis moving port 52 is coupled to the Y-axis shaft 53 and the Y-axis lead screw 54 to the second motor. It installs so that the X-axis moving stand 41 may move along the Y-axis moving stand 51 by the rotation of (32).

By the above configuration, the photographing unit 20 photographs the semiconductor package while moving in the X and Y axes by the first motor 31 and the second motor 32.

FIG. 4 is a diagram illustrating a path of a laser beam incident on a line scan camera of FIG. 3 at different positions depending on a height of a semiconductor package.

The laser beam is differently reflected as the height and height of the semiconductor package are different. In the drawing, H ₁ represents a reference height, H ₂ represents a higher than reference height, and H ₃ represents a lower case than the reference height.

First, when the reference height H ₁ the laser beam is reflected to the path of the R ₁ is incident to a position of R ₁ 'of the line scan camera 22, it is reflected to the path, such as R ₂ when the height H ₂ line scan camera It is incident at the position of R ₂ ′ of 22, and in the case of the height H ₃ , it is reflected in the same path as R ₃ and is incident at the position of R ₃ ′ of the line scan camera 22.

Here, the actual height and defect of the semiconductor package can be detected using the principle that the laser beams reflected differently according to the height are incident to different positions of the line scan camera. It can be obtained from the height data for each incident position stored in 35, and whether the defect is based on the incident position (R ₁ ') of the reference height (H ₁ ) based on the height difference of the incident position (R ₂ ' or R) The difference between ₃ '), i.e., T ₁ or T ₂ is within the allowable height limit, will be considered a good product, and if T ₁ or T ₂ is out of the allowable height limit, it will be considered a defective product.

5A and 5B illustrate an embodiment of a photographing path by the apparatus of the present invention, in which photographing is performed by a path of a region → b region → c region → d region → e region.

As described above, according to the present invention, the laser beam generator and the line scan camera are movable in the XY axis with one jig, and a mirror is installed at a certain angle under each of them, and is irradiated to the inspection object through the mirror and reflected. By allowing the line scan camera to photograph the laser beam, the encapsulation height of the super BGA semiconductor package and the height of the BGA semiconductor package can be inspected accurately, and the size of the inspection equipment can be simplified.

Claims (4)

A laser beam generator 21 for generating a laser beam according to the control signal of the microcomputer 31 and a different position depending on the height of the portion of the semiconductor package 10 in which the semiconductor chip is molded by operating as a control signal of the microcomputer 31. A line scan camera 22 which photographs a laser beam incident on the laser beam and transmits the photographing data to the microcomputer, and a laser beam is irradiated to a portion where the semiconductor chip of the semiconductor package is molded at a predetermined angle under the laser beam generator. A first mirror 23 which refracts as much as possible, and a second mirror installed at a predetermined angle under the line scan camera to refract the laser beam reflected from the molded portion of the semiconductor chip of the semiconductor package to enter the line scan camera ( A photographing unit 20 including 24; A microcomputer (31) which receives the photographing data output from the photographing unit, calculates the real height of the part where the semiconductor chip is molded, and compares it with reference data to determine whether the defect is defective; First and second motors 32 and 33 for moving the photographing unit to the XY axis; A motor driver 34 driving the first and second motors under the control of the microcomputer; A memory unit 35 for storing a program and reference data for an operation of the microcomputer and providing the reference data according to the request of the microcomputer; Encapsulation height and 웝 inspection apparatus of the BGA semiconductor package, characterized in that it comprises a monitor (36) for outputting a photographing result in accordance with the control of the microcomputer (31). (delete) 2. The apparatus of claim 1, wherein height data for each incident position is further stored in the memory unit. 2. The microcomputer (31) according to claim 1, characterized in that the microcomputer (31) further connects a control computer (18) which communicates with the microcomputer via an interface device (17) to transmit a control program and to receive a test result from the microcomputer. Encapsulation height and shock inspection device of BGA semiconductor package.