JP4443092B2 - Semiconductor device and manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a manufacturing method of a dicing process for separating an IC chip of a semiconductor wafer.
[0002]
[Prior art]
In the dicing process of separating a plurality of IC chips formed on the semiconductor wafer, the scribe line portion is cut. However, in the scribe line, various marks necessary for the manufacturing process for forming a circuit on the wafer surface, such as an alignment mark necessary for the photolithography process, a process monitor mark for measuring the line width, misalignment, etching state, etc. Is installed. Cut by applying a (dicing) blade on a scribe line where a plurality of marks are installed, i.e. not formed in a single layer. It is separated into each IC chip. This is performed by so-called grinding.
[0003]
[Problems to be solved by the invention]
As described above, in the dicing process for separating the IC chips of the conventional semiconductor device, the plurality of ICs are ground / cut using a blade on a scribe line in which a plurality of marks are installed. The Sunahachi mark will be cut at the same time. After the wafer cutting for separating the plurality of ICs, most of the marks are deleted by grinding / cutting. Further, a part of the mark remains on the scrub line that is not ground. Then, after dicing, the contact area between the mark base and the mark remaining portion is reduced, and the contact force is reduced. For this reason, there is a problem that a mark whose adhesion is lowered due to an external stress applied during dicing, for example, a pressure of cutting water, is peeled off or curled up and causes a defect in the subsequent mounting process. Even if there is no problem in the mounting process, there is a problem in reliability due to the presence of foreign matter on the surface of the IC chip.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is provided with a mark using a pattern structure that does not separate each layer film forming the mark and the same layer film used in the IC side mark.
[0005]
Further, in the dicing process for separating the IC, dicing is performed by selecting the width of the dicing blade so that the remainder of the mark width set on the scribe line after dicing remains 10 μm or more.
[0006]
By securing the mark installation area after dicing as described above, the mark will not be swollen or peeled off due to the pressure of the cleaning water required for dicing, etc., and there will be no defective factors affecting the subsequent mounting process. I was able to.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail. 1A and 1B are a top view and a cross-sectional view of a semiconductor device according to a first embodiment of the present invention.
[0008]
Reference numeral 1 denotes a semiconductor substrate (wafer substrate) made of, for example, Si. 2 is a scribe line. Dicing saw teeth are applied to the scrub line 2 to cut the wafer. Reference numeral 5 denotes a mark necessary for a process of manufacturing a semiconductor device in the form of a wafer placed on a scribe line. Reference numeral 3 denotes a protective film made of, for example, a nitride film formed on the semiconductor substrate 1. Reference numeral 4 denotes a polyimide film formed on the protective film 3.
[0009]
Reference numeral 6 denotes a protective film formed on the mark 5 and the slit portion of the IC chip. 7 is a polyimide film formed on the mark 5 and the slit portion of the IC chip. Reference numeral 8 denotes a slit portion between the IC chip and the mark 5. When designing the scribe line 2, a mark 5 used for a monitor or the like in the wafer manufacturing process is installed. At this time, the upper layer forming the mark 5, in this embodiment, the protective film 3 and the polyimide film 4 are not separated from the IC chip side, and the protective film 6 of the slit portion 8 and the polyimide film 7 of the slit portion 8 are also formed. Design the pattern as expected.
[0010]
When the IC chip is separated from the scribe line 2 configured as described above in the dicing process, the installation area of the mark 5 with the semiconductor substrate 1 becomes large because the polyimide 4 and the protective film 3 are formed in the slit portion 8. Therefore, the marks 5 after cutting are not frayed or peeled off due to stress such as washing water applied during dicing.
[0011]
FIG. 2 is a sectional view of a semiconductor device according to the second embodiment of the present invention. When forming the mark 5 with two or more types of films, the mark 5 and the slit portion 8 of the IC chip are not filled with all the layers forming the mark 5, but are slit only with the uppermost film, which is the polyimide film 4 in this embodiment. A partial polyimide film 7 is formed. Even when the scribe line 2 configured as described above is diced and the IC chip is separated, the uppermost polyimide film 4 presses the lower layer of the mark 5, so that the mark 5 after cutting may be broken or peeled off. Disappear.
[0012]
3A and 3B are a top view and a cross-sectional view of a semiconductor device according to the third embodiment of the present invention. 9 is the mark width of the mark 5 and is represented by the symbol W, 10 is the mark width remaining in the scribe after dicing, is represented by the symbol Δw, and 11 is the kerf width and is represented by the symbol D. The width of the blade used for dicing, that is, the kerf width 11 and the mark width 9 is determined so that the mark width 10 after dicing remaining on the scribe line after dicing is 10 μm or more, and the mark 5 is set on the scribe line 2. The relationship between the mark width 9, the post-dicing mark width 10 and the kerf width 11 is as follows.
[0013]
10μm ≧ Δw
Δw = W / 2-D
For example, when a blade having a kerf width D of 25 μm is used, a mark width 10 after dicing of 10 μm or more is required. Therefore, a mark 5 having a mark width 9 of 45 μm or more is set on the scribe line 2 from the above formula. The mark 5 configured as above does not peel off the installation area.
【The invention's effect】
As described above in detail, the present invention has the following effects. Even if the mark placed on the scribe line is cut by dicing, the film on the upper layer such as the protective film or polyimide film is not separated, or by having a mark width of a size that can secure a sufficient contact area even when separated, After cutting, the marks will not be damaged or peeled off by external stress. Therefore, after the IC chip is separated, an object peeled off during mounting such as a package does not stick to the pad, and there is an effect of reducing the occurrence of mounting defects. As described above, the present invention has an effect of reducing the defect occurrence rate in the dicing process.
[Brief description of the drawings]
1A and 1B are a top view and a cross-sectional view of a semiconductor device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a semiconductor device in an embodiment of the present invention.
FIGS. 3A and 3B are a top view and a cross-sectional view of a semiconductor device according to an embodiment of the present invention. FIGS.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2 Scribe line 3 Protective film 4 Polyimide film 5 Mark 6 Slit part protective film 7 Slit part polyimide film 8 Slit part 9 Mark width 10 Dicing mark width 11 Calf width

Claims (2)

Consisting of two layers of the protective film and the polyimide film was placed on the scribe lines between IC chip, a mark used to monitor or the like in the wafer fabrication process, the polyimide film and the protective film of the mark which has the same shape as the semiconductor device in which both ends of the protective film and the polyimide film comprises a mark having a portion which is connected without being separated from each protective film and the polyimide film disposed on the IC chip . Consisting of two layers of the protective film and the polyimide film was placed on the scribe lines between IC chip, a mark used to monitor or the like in the wafer fabrication process, the polyimide film and the protective film of the mark which has the same shape as the semiconductor wafer in which both ends of the protective film and the polyimide film comprises a mark having a portion which is connected without being separated from each protective film and the polyimide film disposed on the IC chip For manufacturing a semiconductor device.

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