JPH0950945A - Manufacturing for semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an erroneous step, in which a defective chip carried to a following step or the different grade chips are classified into the same grade, by recognizing data for each chip correctly when the chips are carried to the following step. SOLUTION: Each chip data for a plurality of chips arranged crosswise and lengthwise on a wafer 2 is recognized and stored in an information medium. Then, the wafer 2 is diced into each chip in a manufacturing step. A recognition mark 1 is put on a no-good chip 3 located at a peripheral part of the wafer 2, and the locational data of the chip 3 is also recognized and stored in the medium. After a dicing step for the wafer 2, and the chip 3 is picked up.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is capable of accurately recognizing information of each chip and sending it to the post-process when dicing the wafer to separate the chips and sending the obtained chips to the post-process. The present invention relates to a method of manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In manufacturing a semiconductor device, the following procedure is generally adopted, particularly when shifting from a wafer processing step to an assembly step. First, an inspection called a pellet check is performed on a silicon wafer that has been subjected to various kinds of processing in the wafer processing process and in which a large number of chips to be semiconductor elements are vertically and horizontally arranged. The performance is inspected and the inspection result is stored in an information medium such as a floppy disk. Here, although the inspection depends on the type of chip,
The contents to be stored as the inspection result are whether the chip is a non-defective product, and even if it is a non-defective product, which grade (version) is ranked based on characteristics such as response speed, and further, in the silicon wafer of each chip. The position (address) includes items such as.

After such inspection is completed, the silicon wafer is attached to the wafer sheet, the silicon wafer is diced into individual chips, and the chips are fixed on the wafer sheet. Along with this, it is held on the wafer ring. In addition,
Whether the silicon wafer is pasted on the wafer sheet and then diced, or the wafer is diced and then pasted on the wafer sheet is appropriately selected depending on whether half-cutting or full-cutting is performed as dicing.

Thereafter, the wafer separated into each chip is sent to the pickup device while being held on the wafer ring, and the inspection result previously stored by the pickup device is read from the information medium. Then, this pickup device binarizes or pattern-matches the inspection result previously read out from the chips held on the wafer ring by the attached wafer ring positioning mechanism or XY table. Chips of a desired grade are selected, and the chips are picked up and directly incorporated into a package, or classified into grades and rearranged in a tray or the like. When rearranged on a tray or the like, it is sent to the assembling process in that state and provided for assembly.

[0005]

By the way, when a desired chip is picked up from the wafer ring by the pick-up device, as described above, the position (address) in the silicon wafer of each chip stored in advance in the pellet check step is stored. Based on this, the top chip that becomes a non-defective product is determined, and the remaining chips are sequentially picked up based on this.

However, in picking up the chips in this way and sending them to the subsequent assembling process, there are the following inconveniences. (1) If the positioning of the wafer and the wafer ring is bad at the time of bonding, the next chip is picked up by mistake as the chip to be picked up originally, or the chip address is unknown during the picking operation. As a result, defective products are sent to the subsequent process, or different grades are classified as the same grade and rearranged in one tray. (2) When searching for the leading chip based on the inspection result read from the information medium, if the search area is wide, the adjacent chip may be recognized as the leading chip, and the leading chip may be erroneously recognized. If this happens, the pick-up operation itself will be an erroneous operation. (3) A device trouble occurs during the pick-up operation, and when the wafer is removed and set again to solve the trouble, the address information becomes unclear and the remaining chips cannot be picked up accurately. That is, in the visible range, each chip is a good product or a defective product, and even if it is a good product, its grade (version) is completely indistinguishable,
Since only the address information from the floppy disk or the like is used, there is no standard for recovery from a trouble after the top chip is picked up, which makes the operator very uneasy. (4) If the top chip used as the reference is picked up first when picking up for each classification of grades, the reference will be lost when picking up different classifications.
Then, if the address is set again due to a device trouble or the like in this state, the reset address becomes inaccurate.

The wafer has a diameter of 8 inches,
If the die bonder is compatible with the conventional 6 inch diameter,
It is necessary to rearrange an 8-inch diameter wafer into a 6-inch diameter wafer, but even in that case, many inconveniences such as (1) to (4) may occur.

The present invention has been made in view of the above circumstances, and an object of the present invention is to accurately recognize information for each chip when separating the chips from the wafer and sending them to the subsequent process. It is possible to provide a method for manufacturing a semiconductor device, which can prevent defective products from being sent to a subsequent process, and different grades from being classified as the same grade.

[0009]

According to the method of manufacturing a semiconductor device of the present invention, the information of each individual chip of a wafer in which a large number of chips are aligned vertically and horizontally is recognized and the recognized information is stored in an information medium. Then, when the wafer is diced and separated into individual chips, recognizable identification marks are provided on the mirror chips, which are arranged on the peripheral portion of the wafer and cannot be non-defective, and circuits are not wired. When the information is recognized, the information on the positional relationship of the individual chip with respect to the chip provided with the identification mark is also recognized and stored in the information medium, and then the wafer is diced and picked up. It was taken as a solution.

According to the method of manufacturing a semiconductor device of the present invention,
When an identification mark is provided on the chip that cannot be picked up as a non-defective product and is therefore not picked up, and information on each chip is
Information on the positional relationship of each individual chip with respect to the chip provided with the identification mark is also stored in the information medium, and this wafer is diced thereafter. Therefore, at the time of pickup after dicing, the chip provided with the reference identification mark is always It remains in the wafer ring. Therefore, since the positional relationship between the reference chip and each chip is stored in the information medium and each chip is picked up based on this information, even if trouble occurs, the position (address) of each chip Accurate pickup operation is done without being mistaken.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to its embodiments. The method for manufacturing a semiconductor device of the present invention is a method relating to a series of steps of picking up chips individually cut after dicing by a pick-up device, particularly when shifting from a wafer processing step to an assembling step. The difference of the present invention from the above-mentioned conventional series of steps is that when a large number of chips, which are semiconductor elements, are formed vertically and horizontally in a wafer processing step, an identification mark that can be recognized by a chip that cannot be a non-defective product on the wafer. And that when recognizing individual chip information by the pellet check, the chip provided with the identification mark is used as a reference, and information on the positional relationship of the individual chip with respect to the reference chip is also stored in the information medium. It is in.

In the manufacturing method of the present invention, prior to performing the pellet check, for example, during a wafer processing step, an identification mark is provided on a mirror chip around the wafer, which cannot be a non-defective product and has no circuit wiring. Here, as a method for producing the identification mark, specifically, when forming the wiring by, for example, aluminum vapor deposition in the wafer processing step,
A star (*)-shaped aluminum pattern as shown in FIG. 1 is patterned only on a predetermined chip on the wafer,
This is referred to as an identification mark 1.

The method for producing the identification mark is not limited to the method of aluminum vapor deposition and patterning as described above, and mechanical treatment such as perforation or the like is applied only to a predetermined chip after the wafer processing step, soldering or resin is used. Various methods such as a method of applying attachment, and a method of printing or sticking a sticker can be adopted. Further, the form of the identification mark 1 is not limited to the shape, color, other characteristics, etc. as long as it can be identified at the time of pellet check and at the time of pickup operation. Various shapes such as a diamond shape, a heart shape, a spade shape, a club shape, and a cross shape can be adopted. Also,

Further, as to the formation position of the identification mark 1, as shown in FIG. 1, it is on the chip in the peripheral portion of the wafer 2 at a position which cannot be a non-defective product. That is, the wafer 2
In the peripheral portion of the wafer, since the wafer 2 has a substantially circular shape, a regular square or rectangular shape that naturally becomes a chip shape cannot be obtained, and therefore many chips that cannot be good products are formed. As shown in FIG. 1, the identification mark 1 is provided on the chip 4 next to the topmost and leftmost chip 3 among the non-defective chips.

Then, the wafer 2 provided with the identification mark 1 in this manner is subjected to a pre-operation for the assembling process according to a process substantially similar to the conventional process as shown in FIG. That is, S in FIG.
The pellet check of the wafer 2 shown by T1 is performed. The contents checked and stored in this pellet check are, as before, whether or not the chip is a good product, and even if it is a good product, which grade (version) is based on the characteristics such as response speed is ranked. Furthermore, items such as the position (address) of each chip in the silicon wafer can be mentioned. Especially, regarding the position (address) of each chip in the silicon wafer, the top chip, which is a good product as in the past, is used as a reference. The chip 3 provided with the identification mark 1 that is not a non-defective product next to the next one
Based on

The grades (versions) based on the characteristics are classified into three grades such as A, B and C, and these grades are determined by inspecting each chip as shown in FIG. Although not based on the inspection result, the lot No. And wafer No. Needless to say, is also memorized at the same time.

After such inspection is completed, the wafer 2 is attached to the wafer sheet 5 as shown in FIG. 3, and the wafer 2 is diced to be separated into individual chips, and these chips are further separated. The wafer ring 5 is held together with the wafer sheet 5 in a state of being fixed (ST2 in FIG. 2). Incidentally, whether the silicon wafer is pasted on the wafer sheet and then diced, or whether the wafer is diced and then pasted on the wafer sheet is appropriately selected depending on whether half-cut or full-cut is performed as in the conventional dicing. . Also, apart from this,
When holding the wafer 2 on the wafer ring 6, the lot No. And wafer No. The bar code in which is recorded is pasted on the wafer sheet 5 by a bar code printer.

After that, the wafer 2 separated into each chip
Is sent to a pickup device while being held by the wafer ring 6, and the lot number of the wafer 2 is read by reading the bar code on the wafer sheet 5 by the pickup device. And wafer No. And identify these lots N
o. And wafer No. The previous inspection result corresponding to is read from the information medium. Then, as in the conventional case, this pickup device performs binarization or pattern matching on the previously read inspection result so that the wafer ring 6 is attached to the wafer ring 6 by the attached wafer ring positioning mechanism or XY table. A desired grade chip is selected from each of the held chips (ST3 in FIG. 2), which is picked up and directly incorporated in the package (FIG. 2).
(ST4 in the middle), sorted into grades and rearranged on a tray or the like (ST5 in FIG. 2), or picked up on another wafer ring and positioned and fixed in order to rearrange wafers with different diameters. When rearranged on a tray or the like, it is sent to the assembly process in that state and provided for assembly in the same manner as before, and also when rearranged into wafer shapes having different diameters. After all, it is used for the assembly process by the die bonder in that state.

In such a manufacturing method, the identification mark 1 is provided on the chip that cannot be a good product and is therefore not picked up. Therefore, the chip 3 provided with the identification mark 1 is always the wafer ring 6 even at the time of pickup. It will remain inside. Since the information on the positional relationship of each chip is recognized and stored with reference to the chip 3 provided with the identification mark 1, even if a trouble occurs during pickup, the position (address) of each chip can be mistaken. It can be easily re-recognized without any trouble, which allows an accurate and reliable pickup operation.
That is, even when the address becomes unclear due to a trouble or the like during the pickup operation, the correct position (address) information can be recognized again by recognizing the identification mark 1 again.

In the above embodiment, the identification mark is simply a mark for the reference position, but a plurality of types of this identification mark are prepared and these are symbolized, and the XY (vertical and horizontal) of each chip is added to the identification mark. The information such as the pitch and the inch diameter of the wafer may be provided so that the recognition mechanism in the pickup device can read the information.

[0021]

As described above, according to the method of manufacturing a semiconductor device of the present invention, an identification mark is provided on a chip which cannot be a non-defective product and therefore is not picked up. Information on the positional relationship with respect to the chip provided with the identification mark is also stored in the information medium, and thereafter, by dicing the wafer, the chip provided with the reference identification mark always remains in the wafer ring at the time of pickup after dicing. It was done like this. Therefore, the positional relationship between the reference chip and each chip is stored in the information medium,
Since each chip is picked up based on this information, even if trouble occurs, the position (address) of each chip can be easily recognized again without making a mistake.
This enables an accurate and highly reliable pickup operation. Therefore, it is possible to easily control the accuracy when mounting the wafer and to improve the reliability of the quality of the semiconductor device.

[Brief description of drawings]

FIG. 1 is a plan view of an essential part showing an example of an identification mark formed on a wafer.

FIG. 2 is a diagram for explaining a process flow of the present invention.

FIG. 3 is a plan view for explaining a state in which a wafer is held on a wafer ring.

[Explanation of symbols]

 1 identification mark 2 wafer 3 chip 4 chip

Claims (1)

[Claims] 1. A wafer in which a large number of chips are aligned vertically and horizontally, information of each of the chips is recognized, the recognized information is stored in an information medium, and then the wafer is diced to be cut into individual chips. At this time, a recognizable identification mark is provided on the mirror chip which is arranged around the wafer and in which a circuit that cannot be a good product is not wired, and when the information of each chip is recognized, the identification mark of the individual chip It also recognizes the positional relationship information with respect to the chip provided with, and stores it in the information medium,
After that, the method for manufacturing a semiconductor device is characterized in that the wafer is diced and picked up.