JP2002313997A - Method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automate the detection of the projection caused by the deformation of a bump electrode. SOLUTION: In a semiconductor device manufacturing method which inspects a semiconductor device where a plurality of bump electrodes are made in planar forms on the mounting face of the semiconductor device, a plurality of edges of the bump electrode are detected from the plane image of the mounting face. Based on the detected edge, the center of a ball and the radius of a ball circle are obtained, an inspection circle centering upon the center of the ball is set with a radius where a set value is added to the radius of the ball, and the detection of the edge of the bump electrode is performed along the circumference of this inspection circle, thereby detecting the deformation of the bump electrode. Likewise, the inner margin of the inspection range in the shape of a circle centering upon the center of the ball is set with the radius where the set value is added to the radius of the ball, and an outer margin of the inspection range including the inner margin of this inspection range is set, and the detection of the edge of the bump electrode is formed between the inner margin and the outer margin of the inspection range, thereby detecting the deformation of the bump electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a technique which is effective when applied to inspection of bump electrodes.

[0002]

2. Description of the Related Art In semiconductor devices, with the progress of miniaturization,
2. Description of the Related Art High integration has been performed to increase the scale of a circuit to be mounted on a semiconductor chip area, and more connection terminals are required for a semiconductor device for more circuits to be mounted due to such higher integration. ing. For example, in semiconductor memory devices, the capacity has been increased due to the progress of miniaturization, the bus width has been increased in order to process large-capacity data at high speed, and more external terminals are required.

In order to cope with such an increase in the number of connection terminals, for the purpose of increasing the number of connection terminals, a BGA in which, for example, ball-shaped or column-shaped bump electrodes serving as connection terminals are arranged in a plane on a mounting surface of a semiconductor device. (Ball Grid Arr
ay) type semiconductor devices are used.

In a semiconductor device, burn-in is performed in which a test is performed by accelerating the generation of initial failures by operating the semiconductor device in a high-temperature atmosphere called aging. In a BGA type semiconductor device, burn-in is performed after the test. Burn-in is performed by housing a semiconductor device in a burn-in socket that can be easily attached and detached.

[0005]

In this burn-in socket, conduction occurs when the bump electrode of the semiconductor device is pressed against the terminal of the socket, and the semiconductor device is placed in a high-temperature atmosphere in this state. May cause deformation. The protruding ball deformation generated by such deformation causes a mounting failure when the semiconductor device is mounted on a wiring board or the like. For this reason, it is necessary to perform an inspection and to eliminate the semiconductor device in which the bump electrode is deformed.

However, in the current appearance inspection, it is assumed that an inspection apparatus used for the inspection has a circular bump electrode, and inspections such as package outer dimensions, ball flatness, ball diameter, and ball height are performed. However, since there is no inspection function for the protrusion or the like, such deformation cannot be automatically detected.

Therefore, in order to detect such deformation, a visual inspection using a stereo microscope must be performed.
In this inspection, since the inspection is performed visually for each individual semiconductor device, it depends on the number of electrodes and the like, but it takes about 10 seconds to 60 seconds per semiconductor device, requiring a great deal of labor and time. This significantly increases the cost of product inspection.

An object of the present invention is to solve these problems and to provide a technique capable of automating an inspection for detecting deformation of a bump electrode of a semiconductor device. The above and other problems and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0009]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows. In a semiconductor device manufacturing method for inspecting a semiconductor device in which a plurality of bump electrodes are arranged in a plane on a mounting surface of a semiconductor device, a plurality of bump electrode edges are detected from a planar image of the mounting surface, and the detected edges are used as a basis. Calculate the ball center and the radius of the ball circle, set an inspection circle centered on the ball center with the radius obtained by adding the set value to the ball radius, and detect the presence or absence of the bump electrode along the circumference of the inspection circle. By doing so, the deformation of the bump electrode is detected.

Similarly, a plurality of bump electrode edges are detected from the planar image of the mounting surface, the center of the ball and the radius of the ball circle are determined based on the detected edges, and the radius is obtained by adding a set value to the ball radius. By setting the inner edge of a circular inspection range centered on the center of the ball, setting the outer edge of the inspection range including the inner edge of the inspection range, and detecting the presence or absence of a bump electrode between the inner edge and the outer edge of the inspection range. Then, the deformation of the bump electrode is detected.

According to the present invention described above, it is possible to automate the detection of protrusions due to deformation, and to reduce the cost of product inspection. Hereinafter, embodiments of the present invention will be described. In all the drawings for describing the embodiments, components having the same functions are denoted by the same reference numerals, and repeated description thereof will be omitted.

[0012]

(Embodiment 1) FIG. 1 is a diagram showing a schematic configuration of a visual inspection apparatus for inspecting a semiconductor device according to an embodiment of the present invention. The planar image data of the mounting surface obtained by photographing the bump electrodes 11 arranged in a plurality of planes on the mounting surface of the semiconductor device 1 by the imaging unit 2 such as a camera is sent to the image memory 3, and the image processing unit is performed based on the image data. In step 4, the deformation of the protrusion or the like is detected, and the quality of the semiconductor device is determined based on the presence or absence of a deformation exceeding a predetermined set value.

The detection of this deformation will be described with reference to FIGS. First, a description will be given of an example in which the bump electrode 11 having the planar shape shown in FIG. 2 is deformed and the projection 12 is formed. First, a plurality of ball edges 13 are detected for the bump electrode 11, and as shown in FIG. 3, the ball center 14 and the radius r of the ball circle are obtained by the least square method based on the detected ball edges 13. Next, as shown in FIG. 4, an inspection circle 15 having a radius (r + d) obtained by adding a predetermined set value d to the radius r of the ball with the center 14 as the center is set. The presence or absence of the bump electrode 11 is detected along the circumference.

In this detection, the image of the bump electrode 11 is “white”, and the image of the mounting surface of the semiconductor device is “black”, and the data is binarized, and the data is changed from “black” to “white” or “white” to “black”. Is determined to be the edge of the bump electrode 11. For the protrusion 12 of the electrode 11, "white" data is continuously detected in "black" data, so that the presence / absence is determined.

When the projection 12 exceeding the set value d is not formed by deformation, the edge of the bump electrode 11 is not detected on the inspection circle 15, but the projection 12 exceeding the set value d is formed by deformation. In case, inspection circle 1
5, the presence or absence of the bump electrode 11 is detected.
In this manner, the presence or absence of a deformation exceeding the set value d can be automatically detected based on the presence or absence of an edge on the inspection circle 15.

When detecting such a deformation,
Although a method such as pattern matching is conceivable, it is difficult to measure the length of the protruding portion in pattern matching, so that it is difficult to determine pass / fail based on the size of the protrusion. On the other hand, in the inspection according to the present embodiment in which the inspection circle 15 is set, the projection smaller than the set value d is not detected, and the length of the detected projection 12 is changed by changing the set value d. Can be. Therefore, by setting the allowable value of the protrusion 12 to the set value d, it is possible to make a quality determination according to the length of the protrusion 12.

(Embodiment 2) The appearance inspection apparatus for performing the inspection according to the present embodiment has a schematic configuration similar to that of the apparatus according to the above-described embodiment, and the detection of deformation is also shown in FIG. As shown in FIG.
This is the same until the ball center 14 and the radius r of the ball circle are obtained as shown in FIG.

In the present embodiment, thereafter, as shown in FIG. 5, a circular inspection centered on the ball center 14 and having a radius (r + d) obtained by adding a predetermined set value d to the radius r of the ball. By setting the inner edge 16 of the range, setting the outer edge 17 of the inspection range including the inner edge 16 of the inspection range, and detecting the edge of the bump electrode 11 between the inner edge 16 and the outer edge 17 of the inspection range, Detect deformation. The radius r of the ball in the example shown in FIG.
Is set to a circle having a radius (r + D) obtained by adding a predetermined value D to.

Thus, the inner edge 16 and the outer edge 1 of the inspection range are
The projection 12 is detected by setting an annular inspection range defined by 7 and detecting the edge of this inspection range or detecting the presence or absence of the “white” data. Since the inspection range is widened, the detection of the protrusions 12 is facilitated.
In addition to the detection of foreign substances, it is possible to find foreign substances between the bump electrodes 11.

In order to positively find foreign matter between the bump electrodes 11, as shown in FIG.
Is a rectangle in which the length of each side is equivalent to the interval l between the bump electrodes 11, so that a foreign substance can be inspected over substantially the entire mounting surface on which the bump electrodes 11 are arranged.

The detection of the ball center 14 is as follows.
It is not always necessary to perform the process for all the bump electrodes 11. For example, as shown in FIG. about,
Determine the center of the ball and the radius of the ball circle based on the design values,
It is also possible to detect the projection 12 by the inspection circle 15 or the inspection range set based on these values.
With this configuration, the time required to detect the ball center 14 is reduced, and the inspection time can be reduced.

Although the present invention has been specifically described based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist of the invention. Of course.

[0023]

The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows. (1) According to the present invention, there is an effect that detection of a protrusion due to deformation of a bump electrode can be automated. (2) According to the present invention, the effect (1) has an effect that the time required for the inspection can be reduced. (3) According to the present invention, the effect (1) has an effect that the labor required for the visual inspection can be reduced. (4) According to the present invention, the effects (2) and (3)
This has the effect of reducing the cost required for inspection.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an inspection device used in an embodiment of the present invention.

FIG. 2 is a partial plan view showing an inspection according to an embodiment of the present invention.

FIG. 3 is a partial plan view showing an inspection according to an embodiment of the present invention.

FIG. 4 is a partial plan view showing an inspection according to an embodiment of the present invention.

FIG. 5 is a partial plan view showing an inspection according to another embodiment of the present invention.

FIG. 6 is a partial plan view showing an inspection according to another embodiment of the present invention.

FIG. 7 is a partial plan view showing a modification of the inspection according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Semiconductor device, 2 ... Imaging part, 3 ... Image memory, 4 ... Image processing part, 11 ... Bump electrode, 12 ... Protrusion, 13 ... Ball edge, 14 ... Ball center, 15 ... Inspection circle, 16 ... Inner edge of inspection range , 17 ... Outer edge of inspection range.

Claims (5)

[Claims] 1. A semiconductor device manufacturing method for inspecting a semiconductor device in which a plurality of bump electrodes are arranged in a plane on a mounting surface of the semiconductor device. The center of the ball and the radius of the ball circle are determined based on the detected edge, and an inspection circle centered on the center of the ball is set at a radius obtained by adding the set value to the radius of the ball. A method for manufacturing a semiconductor device, comprising detecting a deformation of a bump electrode by detecting an electrode. 2. A method of manufacturing a semiconductor device for inspecting a semiconductor device in which a plurality of bump electrodes are arranged in a plane on a mounting surface, wherein a plurality of edges of the bump electrodes are detected from a plane image of the mounting surface, and the detected edges are detected. Determine the ball center and the radius of the ball circle based on
Manufacturing a semiconductor device, wherein a deformation of a bump electrode is detected by setting an outer edge of an inspection range including an inner edge of the inspection range and detecting a bump electrode between the inner edge and the outer edge of the inspection range. Method. 3. The method according to claim 2, wherein the outer edge of the inspection range is a circle including the inner edge of the inner inspection range. 4. The method according to claim 2, wherein the outer edge of the inspection range is a rectangle including the inner edge of the inner inspection range. 5. The method according to claim 4, wherein the rectangle has a size corresponding to an interval between the bump electrodes.