JPS6323655B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for processing semiconductor devices after dividing a diced wafer into individual semiconductor chips.

[Summary of the invention]

In the present invention, after dividing a wafer placed on an adhesive sheet into individual semiconductor chips, the adhesive sheet is stretched and one of the wafer standard sizes having a similar shape to the wafer and defined in stages is used. The wafer is attached to a handling ring having external dimensions that match that of the semiconductor chip, and the handling ring is held by the wafer jig to process the semiconductor chip, thereby performing processes such as dicing, cleaning, peeling, and die bonding. This is designed to be easy to do.

[Conventional technology]

Today, advances in semiconductor technology such as IC and LSI have led to rapid development of the electronics industry, greatly contributing to the advancement of industry and the creation of a prosperous economic society. These ICs and LSIs are not only used in electronic computers, but also include familiar examples such as televisions, radios, etc.
It is also used in watches, audio, cameras, cars, etc. Furthermore, these applications can be applied in a variety of ways, such as as logic circuits, memory (storage elements), imagers (imaging devices), amplification, and even microcomputers with system functions. It is used to comprehensively control equipment.

Incidentally, these semiconductor elements used as ICs, LSIs, etc. are manufactured through various manufacturing processes. That is, manufacturing a wafer to serve as a substrate, forming semiconductor chips on this wafer by subjecting the wafer to etching, impurity diffusion, ion implantation, vapor phase oxide film deposition, and metal vapor deposition for electrodes, and separating and bonding the semiconductor chips by dicing. , assembly processes such as molding, etc.

Here, if we pay particular attention to the above-mentioned semiconductor chip separation process, in the above-mentioned separation process, the wafer is diced or cut using a diamond cutter or the like to separate each semiconductor chip, and the semiconductor chips are individually taken out. It was necessary to transport the lead frame to a predetermined position and fix it. For this reason, in the past, a wafer that had been cut halfway through dicing was packaged in two sheets, separated by rollers, and then the upper sheet was peeled off and the separated semiconductor chips were separated into individual semiconductor chips using vacuum tweezers. A method of transferring the lead frame to the lead frame using, for example, is used.

However, in the conventional method described above, the cut is made halfway through the wafer's thickness and the remaining part is divided by the pressure of a roller, so the outer periphery of each semiconductor chip is likely to be damaged. There was a risk that fine powder would be generated and adhere to the surface of the semiconductor chip, causing adverse effects. Furthermore, when dividing the wafer, the workability is extremely poor, as each wafer must be removed and packaged in a sheet.

Therefore, in the past, the wafer was adhesively fixed to the upper surface of an adhesive sheet, the semiconductor chips were completely cut during dicing, and then the adhesive sheet was stretched to create a gap between the divided semiconductor chips. A method is known in which each semiconductor chip is peeled off from the adhesive tape using vacuum tweezers or the like and transferred at the same time. The above method does not cause damage to the semiconductor chip and has good workability.

By the way, in the above-mentioned dicing method,
Since the silicon that forms the wafer is cut, fine powder of the cut silicon remains on the surface of the semiconductor chips, making it necessary to clean the semiconductor chips with dicing and stretching agents. At this time, if the adhesive sheet to which the semiconductor chip is adhered can be held in some way during the cleaning process, the semiconductor chip will be easier to handle and workability will be improved.

Therefore, conventionally, as shown in FIG. 4, a plastic ring 100 made of synthetic resin or the like and having a concave groove in the radial direction on its outer circumferential surface,
A method is adopted in which an upper semiconductor chip 101 is attached, a stretched adhesive sheet 102 is layered, the outer periphery of this sheet 102 is rolled into a groove, and then tightened with a metal fitting 103.

[Problem that the invention seeks to solve]

However, in the conventional method as mentioned above,
Since it is necessary to attach the metal fitting 103 to the plastic ring 100, workability is extremely poor, and when moving to a process after dicing such as a cleaning process, special equipment is required to hold the plastic ring 100 in each device such as a cleaning machine. It is necessary to provide a jig, which is very difficult to handle and costs a lot.

Therefore, the present invention was proposed in order to solve the problems of the above-mentioned conventional techniques, and does not require metal fittings like the conventional techniques, and can easily perform the process after dicing. It is an object of the present invention to provide a semiconductor device processing method that can utilize conventional equipment without providing special jigs and can reduce costs.

[Effect]

In the present invention, the divided semiconductor chips are attached to an adhesive sheet and transferred to a processing step while being fixed to a semiconductor element handling ring corresponding to a standard size.

Therefore, the semiconductor chips are treated in the same way as wafers, using conventional equipment when performing cleaning, die bonding, and other treatments.

〔Example〕

Hereinafter, specific embodiments of the semiconductor device processing method according to the present invention will be described in order of each step with reference to the drawings.

To perform processing such as cleaning and die bonding on a semiconductor element on which a predetermined integrated circuit is formed,
First, as shown in FIG. 1, a wafer 1 on which a large number of integrated circuits have been formed is mounted on a dicing machine (not shown) and completely cut by a diamond blade to divide it into semiconductor chips 2 corresponding to each integrated circuit. The wafer 1 is formed from a single crystal of silicon, and the semiconductor chip 2 is formed through processes such as etching, impurity diffusion, ion implantation, vapor phase oxide film deposition, and metal vapor deposition for electrodes. The predetermined semiconductor chip 2 described above is formed on the surface. The wafer 1 is placed on the upper surface of an adhesive sheet 3 for dicing, and the outer periphery of the adhesive sheet 3 is supported by a ring-shaped dicer frame 4.

Next, the semiconductor chip 2, which has been completely cut by a diamond blade (not shown) on the adhesive sheet 3 supported by the dicer frame 4 as described above, is left attached to the adhesive sheet 3. Transfer to a stretching machine and stretch. The above stretching machine is
As shown in FIGS. 3 and 4, it is comprised of a frame pedestal 5 and a movable pedestal 6 that can be moved up and down. A ring-shaped groove is provided on the upper surface of the movable pedestal 6, and a semiconductor element handling ring 7 made of metal and having a diameter slightly larger than that of the wafer 1 is fitted into the groove 2. This semiconductor element handling ring 7 is formed into a ring shape, with one end 7A cut out, and its outer circumferential shape is similar to that of the wafer 1 described above.

Here, the external dimensions of semiconductor wafers are standardized, and a plurality of types of standard wafers having gradually different external dimensions are defined. The outer peripheral shape of the handling ring 7 is formed to match one of these wafer reference sizes.

For example, if the diameter of the wafer 1 is 3 inches, use the handling ring 7 with a diameter of 4 inches, and if the diameter of the wafer 1 is 4 inches, use the handling ring 7 with a diameter of 5 inches. A semiconductor handling ring 7 having the same size and shape as a standard wafer, which is slightly larger than the wafer 1, is used. The upper surface of the semiconductor element handling ring 7 is located at a position slightly lower than the upper surface of the movable pedestal 6, and further,
A double-sided tape 8 is attached to the upper surface of the handling ring 7.

On the other hand, the dicer frame 4 to which the wafer 1 is attached is fixed to the frame holder 5 of the stretching machine described above. At this time, the upper surface of the frame holder 5 of the stretching machine and the upper surface of the movable holder 6 form the same plane, and the sheet 3 to which the wafer 1 is attached is placed on the upper surface of the movable holder 6. It is becoming more and more common. After that, move the movable cradle 6 to the third
The adhesive sheet 3 is stretched by raising it as shown in Figure B. As a result, the adhesive sheet 3 is stretched, and the intervals between the semiconductor chips 2 of the diced wafer 1 are widened, and the division of the semiconductor chips 2 is completed.

Furthermore, after the stretching, the semiconductor element handling ring 7 disposed in the groove on the movable holder 6 is pressed against the back surface of the adhesive sheet 3 using a method such as air pressure, and the double-sided tape provided on the upper surface of the handling ring 7 is pressed. 8, the handling ring 7 and the adhesive sheet 3 are adhered and fixed.

Then, the adhesive sheet 3 to which the semiconductor chip 2 is attached is cut out along the handling ring 7, and the process proceeds to a cleaning process by washing with water. At this time,
Since the outer peripheral shape of the handling ring 7 is the same as that of a standard wafer, it can be easily attached to a cleaning device (not shown) in the same way as a wafer. That is, the handling ring 7 can be held with a jig for holding standard wafers, and there is no need to use a special jig. This standard wafer jig is generally widely used and can be easily used.

Further, the handling ring 7 is transferred to a semiconductor chip peeling device to peel off each semiconductor chip 2 on the adhesive sheet 3, and then proceed to an assembly process such as die bonding. At this time, the handling ring 7 can be similarly easily attached to a peeling device (not shown).

In the above embodiment, the divided semiconductor chips 2 can be handled in the same way as wafers, and since the shape of the semiconductor element handling ring 7 is the same as that of a standard wafer, it can be easily attached to a cleaning device, etc. It's becoming possible. Furthermore, it has become possible to create an integrated automated system for everything from dicing to cleaning, peeling, and die bonding.

〔Effect of the invention〕

According to the present invention, each divided semiconductor chip is handled by being fixed to an adhesive sheet and attached to a semiconductor element handling ring corresponding to a standard wafer size. When proceeding to the processing step after dicing, there is no need to provide special jigs for each device such as a washing machine, and conventional equipment can be used.

Therefore, the divided semiconductor chips can be handled in the same manner as wafers, which improves work efficiency and is also advantageous in terms of equipment investment.

[Brief explanation of drawings]

Fig. 1 is an external perspective view showing a wafer attached to an adhesive sheet, Fig. 2 is an external perspective view of a semiconductor element handling ring used in the present invention, and Figs. 3A and 3B are adhesive sheets. Figure 3A is a plan view before stretching, Figure 3B is a drawing process.
is a longitudinal cross-sectional view taken along the line A-A in FIG. 3A after stretching. FIG. 4 is a longitudinal sectional view showing an example of a conventionally used semiconductor element handling ring. 1... Wafer, 2... Semiconductor chip, 3... Adhesive sheet, 7... Semiconductor element handling ring.

Claims (1)

[Claims] 1. After cutting a wafer placed on an adhesive sheet into individual semiconductor chips, the adhesive sheet is stretched, and a wafer standard having a shape similar to the wafer and defined in stages is set. The semiconductor chip is attached to a handling ring having external dimensions matching one of the wafer reference sizes, and the semiconductor chip is processed by holding the handling ring with a standard wafer jig corresponding to the wafer reference size. Semiconductor device processing method.