JPS6044828B2 - Manufacturing method of semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device, and particularly to a so-called bump-type semiconductor device having a structure in which external connection terminal wiring is in the form of a bump, and a method for manufacturing the same.

A conventional bump-type semiconductor device, as shown in FIG.
A silicon wafer substrate 1 on which a large number of semiconductor elements having bump electrodes 9 are formed and a metal film 10 for mounting on the back surface.
After gluing on the fixed substrate 17 with the material 16 and making scribe scratches on the surface of the silicon wafer substrate 1,
Mechanical separation grooves were provided throughout the thickness of the silicon wafer substrate 1 to separate the semiconductor elements into individual semiconductor elements.

For this reason, damage defects 18 occur at the periphery of each semiconductor element. For this reason, the external shape of the individual device may be defective, or the lead electrode after bonding may come into contact with the missing portion of the substrate end, causing malfunction of the electrical circuit. Another drawback is that during the manufacturing process of the above device, the bonding material 16 is attached to the fixed substrate 17 before breaking and separating into individual semiconductor elements.
Since the bump part 9 is fixed by gluing, if the bump part 9 is bonded and mounted in that state, the gluing material 16 will rise up the groove between the individual semiconductor elements due to the heat and pressure during bonding, and the surface part of the semiconductor element will rise. This caused electrical short circuits due to poor bonding and mounting connections and dirt. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a method for producing a semiconductor substrate structure in which there is no chipping of the peripheral edge of a singulation device board, and in which there is no rise-up defect of the gluing material during bonding mounting. The bump-type semiconductor device of the present invention includes the steps of: providing a cutting separation groove from the main surface side of a semiconductor wafer substrate to the middle of the thickness of the substrate; providing the separation groove over a predetermined entire area of the wafer substrate; and adhesive bonding. a step of attaching a sheet to the back side or both sides of the wafer substrate; a step of braking the remaining thickness of the substrate in the separation groove while being fixed to the gluing sheet; and a step of attaching the sheet to the back side gluing sheet and the singulation device. The semiconductor device can be manufactured by a method for manufacturing a semiconductor device, which includes the steps of successively bonding and mounting the semiconductor device and separating the semiconductor device from the bonding sheet.

According to the present invention, in the manufacturing method, mechanical cutting is performed to the middle of the thickness of the substrate, and the remaining thickness is separated by braking, so that there is no need to cut deeply into the bonded substrate using, for example, dicing teeth as in the conventional method. Eliminates missing defects at the edges, or eliminates the need for a mounting board.
The sheet used for braking is directly transferred to the bonding process and cured at the bonding temperature, reducing its adhesiveness and allowing it to be separated individually. This eliminates the contamination of the wax material used in the past, and improves product quality. This can result in a device with improved manufacturing yield.

Moreover, since there is no missing part at the end of the substrate in the completed product of this kind, there is no defective contact between the bonding lead electrodes and the electrical reliability of the product is improved. Next, the present invention will be explained with reference to the drawings and examples.

For convenience of explanation, a case of a bump-type semiconductor device with a two-layer wiring circuit structure is shown, and the polarity of element electrodes in the semiconductor substrate is omitted. FIG. 1 is a sectional view of one embodiment of a bump-type semiconductor device of the present invention.

Epitaxial layer 2 and SiO are formed on one main surface of silicon substrate 1.
2 film, an insulating film 3 such as a Sl3N4 film, and a diffusion element region 4 are provided, a lower wiring region consisting of an A1 film 5 and an Al2O3 film 6 is provided on the main surface, interlayer insulation is provided with a SiO2 film 7, and a Ti-
An upper wiring region consisting of a Pt-Au film 8 is provided, and a thick Au
A film 9 is provided, and a metal film 10 for mounting, for example TiA, is provided on the back surface.
u, Cr-AuMO-Ni-Au, etc. are provided.

This bump terminal type silicon substrate 1 is characterized in that the side surface portions have a stepped structure, and in particular, the back surface portion protrudes more than the main surface portion.

For example, the thickness of the silicon substrate is reduced, and the metal film deposited on the back side of the substrate is reduced. Including the thickness of the protruding part! , when the protrusion width is W1, t1=-350μM, t2:
:200 μM, a bump-type semiconductor device with a step-like structure on the side surface can be manufactured with dimensions of wl+50 μm. Incidentally, the side surface including the protruding portion may be of an upright type or an inclined type;
l, ·T2wl are not limited to the dimensions of each embodiment. The structure of this embodiment has the effect of preventing abnormal chipping at the peripheral edge of the device substrate associated with singulation and separation, and preventing electrical contact between the leads and the substrate during bonding mounting.

Next, a method for manufacturing a bump-type semiconductor device according to the present invention will be explained.

FIGS. 2a to 2e are cross-sectional views illustrating a manufacturing method of one embodiment of the semiconductor device of the present invention.

Bump terminal wiring 3 is provided on the insulating film 2 on the main surface of the silicon wafer substrate 1, and a predetermined mounting metal film, such as MO-Ni-AulO, is provided on the back surface in alignment with the singulation/separation/region 11. Figure 2a).

Next, the silicon substrate 1 is cut along the singulation separation region 11 on the main surface to a thickness halfway through the thickness t1 to form separation grooves 12.

At this time, if the width is 350 μm, L. ::100~150
It is sufficient to use a dicing method or a laser scribing method (Fig. 2b). Subsequently, adhesive gluing sheets 13a and 13b are pasted on the front and back surfaces of the wafer-substrate having the separation groove 12, and while the wafer is held thereon, a crack 14 is made from the pointed end of the separation groove 12 to separate the wafers. Separate into two pieces of equipment.

It is preferable that the bonding sheet at this time has adhesiveness, and that the sheet material is thermosetted under the heating conditions during bonding in the next step, making it easier to remove the device, for example, 0.3~ A thick dry film of about 0.5 μm (Liston film made by Dupont) or a silicone resin film of 5 to 10 p.
It may be an epoxy resin film coated on the surface with a thickness of m.
Its characteristic feature is that it has soft properties and can be obtained by braking a wafer-to-substrate singulation device (FIG. 2c). In this state, the sheet material 13a on the main surface is peeled off and the lead electrodes 15 of the mounting board (lead frame) are bonded to the bump terminals 3.

At this time, unlike in the past, wax material is not used, so it is possible to eliminate stains on the gluing material from the gluing sheet, such as wax rising up the side of the individual piece device and adhering to the main surface (Figure 2 d). . Finally, the individual piece device is pulled upward while still being adhered to the bonded lead electrode 15, and this operation is repeated to process all the predetermined individual pieces within one wafer substrate (FIG. 2e).

As shown in the above embodiment, even if mechanical cutting is performed from the main surface side, the entire thickness of the silicon substrate and a hard fixed substrate such as a quartz plate as in the conventional method are not cut at the same time. Damage to the teeth can be prevented, defective defects at the edges of individual device boards can be eliminated, electrical contact between bonding leads and the board can be prevented, and low melting point wax is not used as a bonding material, so the wax can be easily contaminated. It also helps prevent, improves quality,
It is possible to improve productivity by improving manufacturing yield and saving labor.

Although the structure and manufacturing method of the present invention have been explained using one embodiment, the present invention is not limited to the type of semiconductor device, such as MOS type, bipolar type, wired circuit structure, bonding type, etc.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of one embodiment of a bump-type semiconductor device of the present invention, and FIGS. 2 a-e are cross-sectional views illustrating a manufacturing method of one embodiment of the semiconductor device of the present invention. FIG. 3 is a cross-sectional view showing one process of manufacturing a conventional bump-type semiconductor device. 1...Silicon substrate, 2...
...Epitaxial layer, 3...SiO2 or S
i3N4 film, 4...diffusion element region, 5...
...A1 wiring, 6...Al. O3 membrane, 7...
...SiO2 film, 8...Ti-Pt-Au film, 9...Au bump terminal, 10...back metal film, 11...pieces Fragment separation area, 12...
... Dying groove, 13a, b ... Adhesive sheet, 14 ... Braking part, 15 ...
Lead electrode, W1...Protrusion width of the side of the silicon substrate,...Total thickness of the silicon substrate,...
・Thickness of the protruding part of the silicon substrate.

Claims (1)

[Claims] 1. A step of forming a large number of semiconductor elements having bump electrodes for leading out external electrodes on a semiconductor wafer, a step of providing a separation groove shallower than the thickness of the semiconductor wafer between the semiconductor elements, and a step of forming a separation groove shallower than the thickness of the semiconductor wafer between the semiconductor elements; a step of coating the front and back surfaces of the semiconductor wafer with a thermosetting and adhesive bonding sheet; a step of breaking and separating the semiconductor wafer having the bonding sheet on both the front and back surfaces at the separation groove; removing the gluing sheet from the front surface of the semiconductor wafer after the fracture separation; and attaching external leads to the bump electrodes of the fracture-separated semiconductor elements whose back surfaces are bonded to the gluing sheet while heating. A method of manufacturing a semiconductor device, characterized in that the semiconductor element is separated from the bonded leads on the back surface.