JPH06275686A - Method and device for manufacturing semiconductor device - Google Patents

Abstract

PURPOSE:To solve a trouble, which is accompanied by the good or bad of the marking of a defect mark put on a characteristic defective of a plurality of semiconductor elements formed on a semiconductor wafer. CONSTITUTION:A characteristic inspection of a plurality of semiconductor elements 2 formed on a semiconductor wafer 1 is made in order, a defect mark is marked on a semiconductor element 2 having a characteristic failure and positional information on the marked semiconductor element 2 on the wafer 1 is made to store in a storage element 9. The elements 2 on the wafer 1 are imaged by a camera 11, positional information, which is obtained from the image, on the element 2 having the defect mark on the wafer 1 and the positional information, which is read out from the element 9, on the element 2 to be marked are compared with each other by a comparison decision circuit 13 and a good or bad decision on the marking is made by whether the contents of both information coincide with each other or not. By this decision, a control to send the wafer 1 having a non-defective mark to the following process is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing method and a manufacturing apparatus in a characteristic inspection process for a plurality of semiconductor elements formed on a semiconductor wafer.

[0002]

2. Description of the Related Art In a characteristic inspection process for a plurality of semiconductor elements formed on one semiconductor wafer, defective marks such as ink and scratches are marked on the semiconductor elements determined to have defective characteristics. The semiconductor wafer on which the characteristic inspection of the semiconductor element has been completed is divided into individual semiconductor elements, and a good semiconductor element having no defective mark is mounted on a lead frame or the like.

The characteristic inspection of each semiconductor element of the semiconductor wafer is performed by using a characteristic inspection device (6) and a marking device (7) as shown in FIG. 3 (a). One semiconductor wafer (1) is supplied onto a horizontal characteristic inspection table (5) from a magazine (4) that stores a plurality of semiconductor wafers (1) in multiple stages. As shown in FIG. 3B, the semiconductor wafer (1) has a plurality of semiconductor elements (2) arranged in a grid pattern.

A characteristic inspection device (6) above the table (5)
When the semiconductor wafer (1) is supplied on the table (5) with the marking device (7) arranged, the characteristic inspection device (6) causes the plurality of semiconductor elements (2) of the semiconductor wafer (1).
The characteristic inspections of are sequentially performed. In parallel with the progress of the characteristic inspection, a defective mark (3) is marked on the semiconductor element (2) having a defective characteristic.

For example, when the inspection result of one semiconductor element (2) is determined to be defective, a marking command signal is output from the characteristic inspection device (5) to the marking device (7),
A marking device (7) marks a defective mark (3) on a semiconductor element (2) determined to have a defective characteristic. The defective mark (3) is, for example, dot-shaped ink applied on the semiconductor wafer (1) or scratches on the upper surface of the semiconductor wafer (1).

After the characteristic inspection is completed, the semiconductor wafer (1) is stored in another magazine (8) from the table (5). The characteristic-tested semiconductor wafer (1) housed in the magazine (8) is sent to a later step, for example, a mounting step, and divided into individual semiconductor elements (2). For each divided semiconductor element (2), the presence or absence of a defective mark (3) is detected from the image captured by the camera, and it is sorted into good and defective products with characteristics and only good products are mounted on a lead frame or the like. And a semiconductor device is manufactured.

[0007]

The defective mark to be marked on the semiconductor element of the semiconductor wafer has a clear shape, color and size which can be easily recognized in the image processing in the subsequent process. A defective mark may become unclear due to a malfunction or marking conditions and may not be accurately detected by image processing in the mounting process.

For example, in the case where the marking device is provided with an ink nozzle for applying a fixed amount of ink on a semiconductor element having a poor characteristic to perform marking, marking is performed on the semiconductor element due to a good or poor way of ejecting the ink from the ink nozzle. The amount and form of the generated ink may fluctuate, and the defective mark of the ink may be blurred and unclear. If the marking device scratches the semiconductor element with defective characteristics with a pin, the depth and size of the scratch on the semiconductor element will be reduced due to bending or wear of the pin, making the defective mark of the scratch unclear. May be.

Such an unclear defect mark may not be recognized during image processing of individual semiconductor devices divided from a semiconductor wafer in a later process. As a result, there has been a problem that a semiconductor element having a poor characteristic with an unclear defective mark is mistakenly recognized as a semiconductor element having a good characteristic and mounted on a lead frame or the like. Further, such unclear marking of defective marks often occurs continuously in a plurality of semiconductor wafers, and the above-mentioned defect occurs continuously in a plurality of semiconductor wafers, which is a cause of deteriorating the manufacturing yield of semiconductor devices. Has become.

An object of the present invention is to provide a method and an apparatus for manufacturing a semiconductor device, which eliminates the problems caused by the quality of defective marks to be marked on semiconductor elements of a semiconductor wafer.

[0011]

According to the present invention, a plurality of semiconductor elements formed on a semiconductor wafer are sequentially inspected for characteristics,
A semiconductor wafer after the characteristic inspection is performed in a step subsequent to the characteristic inspection step in which a defective mark is marked on the semiconductor element determined to have the characteristic defect and the position information in the semiconductor wafer of the semiconductor element with the defective mark is stored in a storage element. Each semiconductor element is imaged with a camera, the presence or absence of a defective mark on the semiconductor element is detected from the image processing, and the position information on the semiconductor wafer of the semiconductor element recognized as having a defective mark and the position information are read from the storage element. The above object is achieved by providing a defective mark recognition step of comparing the positional information of the semiconductor elements to be marked.

Further, according to the present invention, a plurality of semiconductor elements formed on a semiconductor wafer are sequentially inspected for characteristics, and a defective mark is marked on a semiconductor element determined to have a defective characteristic. A characteristic inspection device that stores position information on a semiconductor wafer in a storage element, and an image recognition device that images each semiconductor element of the semiconductor wafer after the characteristic inspection with a camera and detects the presence or absence of a defective mark on the semiconductor element from the image processing. And the position information of the semiconductor element, which is recognized by the image recognition apparatus as having a defective mark on the semiconductor wafer, and the position information of the marked semiconductor element read from the storage element of the characteristic inspection apparatus, are compared to obtain a defective mark of the semiconductor element. In a semiconductor device manufacturing apparatus including a comparison / determination circuit for determining the quality of Accomplish.

[0013]

Function: Position information on the semiconductor wafer of the semiconductor element to be marked, which is performed during the characteristic inspection of the semiconductor element of the semiconductor wafer, and position information on the semiconductor wafer of the semiconductor element recognized as having a defective mark from the semiconductor element image after the characteristic inspection. If the two pieces of position information match with each other, it can be determined that the defective mark is properly marked. If the position information of the marked semiconductor device and the position information of the defective mark recognition semiconductor device do not match,
The defective mark is so unclear that it cannot be recognized by image processing, and the occurrence of malfunction of the marking device can be predicted.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS. It should be noted that the same or corresponding portions of the manufacturing apparatus shown in FIG. 1 as those of the manufacturing apparatus of FIG.

Characteristic inspection of a plurality of semiconductor elements (2) of one semiconductor wafer (1) supplied from the magazine (4) onto the table (5) is sequentially performed by the characteristic inspection device (6), and the characteristic inspection result is obtained. The defective device (2) is marked with a defective mark (3) by a marking device (7). Further, the storage element (9) attached to the characteristic inspection device (6) stores the position information of the semiconductor element (2) to be marked with the defective mark (3) on the semiconductor wafer (1).

The semiconductor wafer (1) whose characteristics have been inspected for all the semiconductor elements (2) is moved to another defective mark recognition table (10), and a camera (11) arranged above the table (10). Each semiconductor element (2) of the semiconductor wafer (1) is imaged with. The image data captured by the camera (11) is sent to the image recognition device (12), where image processing is performed to detect the presence or absence of the defective mark (3) on the semiconductor element (2),
The position information on the semiconductor wafer (1) of the semiconductor element (2) recognized as having a defective mark is obtained.

When the image recognition device (12) finishes the image processing of all the semiconductor elements (2) of the semiconductor wafer (1) and obtains the position information of all the defective mark recognition semiconductor elements (2),
The position information of the marked semiconductor element (2) stored in the storage element (9) of the characteristic inspection device (6) is read out, and this position information D ₁ and the defective mark recognition semiconductor element from the image recognition device (12) ( 2) Position information D ₂ of comparison judgment circuit (1
Enter in 3). The comparison / determination circuit (13) compares whether or not the contents of the two pieces of position information D ₁ and D ₂ match, and determines whether the defective mark (3) is defective or not based on the comparison result. Two
The two pieces of position information D ₁ and D ₂ and their comparison are performed as follows.

For example, as shown in FIG. 2 (a), the semiconductor wafer (1) has the Nth characteristic-tested semiconductor element (2 ') that has a defective characteristic and is marked with a defective mark (3). Then, the storage element (9) stores the N-th information with marking in the memory map. It is assumed that the semiconductor wafer (1) is imaged by the camera (11) and the defective mark (3) marked on the N-th semiconductor element (2 ′) is recognized by the image recognition device (12). in this case,
The comparison / determination circuit (13) compares the signal with marking and the signal with defective mark of the same content with respect to the N-th semiconductor element (2 ′) of the semiconductor wafer (1), and the defective mark (3) is detected. Judged as clear and normal marking,
The marking OK signal is output.

Such a determination is performed for all the marked semiconductor elements (2 ') of the semiconductor wafer (1). After the image recognition of one semiconductor wafer (1), if the final judgment result of the comparison judgment circuit (13) is marking OK, the semiconductor wafer (1) is supplied from the table (10) to the magazine (8), It is sent to the subsequent process.

As shown in FIG. 2B, the N-th semiconductor element (2 ') of the semiconductor wafer (1) has a defective characteristic,
Even when the defective mark (3) to be marked on this is blurred and small in size, the storage element (9) stores the N-th information with marking in the memory map. When the defective mark (3) of the N-th semiconductor element (2 ') of the semiconductor wafer (1) is unclear which cannot be recognized by the image recognition device (12), the image recognition device (12) causes the comparison judgment circuit (13) to detect it. The N-th semiconductor element (2 ') outputs information without a defective mark. Then, the comparison / determination circuit (13) compares two pieces of contradictory information, that is, the information with the marking and the information without the defective mark with respect to the N-th semiconductor element (2 ′) of the semiconductor wafer (1), and the marking is performed. The signal of the defective marking NG is output.

Further, as shown in FIG. 2C, although the N-th semiconductor element (2 ') of the semiconductor wafer (1) has a defective characteristic, it may not be marked with a defective mark. is there. Even in such a case, the storage element (9) stores the Nth marking information in the memory map. On the other hand, the image recognition device (12) outputs information to the comparison / determination circuit (13) that the N-th semiconductor element (2 ') has no defective mark. As a result, comparison judgment circuit (13)
Is the N-th semiconductor element (2 ') of the semiconductor wafer (1)
In comparison with the information with marking and the information without defective mark, a signal of marking NG is output.

When the comparison / judgment circuit (13) outputs the marking NG as shown in FIGS. 2 (b) and 2 (c), it is recognized that the marking is not normally performed in the characteristic inspection process, and the subsequent semiconductor wafer Characteristic inspection, marking stopped,
Adjustment of the marking device (7) is performed. Therefore, only the semiconductor wafers (1) with marking OK are supplied from the table (10) to the magazine (8). When the semiconductor wafer (1) stored in the magazine (8) is sent to the mounting process and the individual semiconductor elements (2) divided from the semiconductor wafer (1) are subjected to image processing, the semiconductor elements (2 ′) with defective characteristics are detected. Since the defective mark (3) is clear, there is no concern that the semiconductor element (2 ') with defective characteristics will be mistaken for a good product.

For convenience of explanation of the present invention, a table (5) for inspecting the characteristics of each semiconductor element (2) of the semiconductor wafer (1) and a table (10) for recognizing a defective mark (3).
However, it is also possible to perform the characteristic inspection and the defective mark recognition with one table.

[0024]

According to the present invention, the positional information on the semiconductor wafer of the semiconductor element to be marked on the semiconductor wafer and the positional information on the semiconductor wafer of the semiconductor element recognized as having a defective mark from the semiconductor element image after the characteristic inspection are displayed. By comparing whether the contents match or not, it is possible to judge the quality of the marking in the characteristic inspection process, and by this quality judgment it is possible to prevent the continuous occurrence of defective marking on multiple semiconductor wafers in the characteristic inspection process. The wafer can be sent to the subsequent process, and the manufacturing yield of the semiconductor device can be improved.

[Brief description of drawings]

FIG. 1 is a side view showing an outline of a semiconductor device manufacturing apparatus showing an embodiment of the present invention.

FIG. 2 is a block diagram for explaining the operation principle of the present invention, in which (a) is a case where two pieces of marking information match.
(B) and (c) show cases where the two marking information do not match.

3A is a side view schematically showing a conventional semiconductor device manufacturing apparatus, and FIG. 3B is a plan view of the semiconductor wafer in FIG. 3A.

[Explanation of symbols]

 1 Semiconductor wafer 2 Semiconductor element 2'Semiconductor element 3 Defect mark 6 Characteristic inspection device 9 Storage element 11 Camera 12 Image recognition device 13 Comparison judgment circuit

Claims (2)

[Claims] 1. A semiconductor device having a plurality of semiconductor elements formed on a semiconductor wafer is sequentially inspected for characteristics, a defective mark is marked on the semiconductor element determined to have a defective characteristic, and the position of the semiconductor element marked with the defective mark on the semiconductor wafer. A characteristic inspection process of storing information in a memory element, and image pickup of each semiconductor element of the semiconductor wafer after the characteristic inspection with a camera, and the presence or absence of the defective mark on the semiconductor element is detected from the image processing to detect that there is a defective mark. A method of manufacturing a semiconductor device, comprising: a defective mark recognition step of comparing the position information of the recognized semiconductor element on the semiconductor wafer with the position information of the marked semiconductor element read from the storage element. 2. A plurality of semiconductor elements formed on a semiconductor wafer are sequentially subjected to characteristic inspection to mark a defective mark on a semiconductor element determined to have a defective characteristic and the position of the semiconductor element on which the defective mark is marked on the semiconductor wafer. A characteristic inspection device that stores information in a storage element, an image recognition device that images each semiconductor element of a semiconductor wafer after the characteristic inspection with a camera, and detects the presence or absence of the defective mark on the semiconductor element from the image processing, The position information on the semiconductor wafer of the semiconductor element recognized as having a defective mark by the recognition device and the position information of the marked semiconductor element read from the storage element of the characteristic inspection device are compared to determine whether the marking in the characteristic inspection process is good or bad. An apparatus for manufacturing a semiconductor device, comprising: a comparison / determination circuit for determining.