JP2001015621A - Manufacture of semiconductor chip and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor chip capable of highly reliably realizing an ultra-thin packaging of a semiconductor device, and a semiconductor device in which the semiconductor chip is packaged on a wiring board. SOLUTION: A method of manufacturing a semiconductor chip consists of a step S13 of thinly processing the surface, which is opposite to the surface of a semiconductor wafer having an electrode part on which the electrode is formed, so that the semiconductor wafer has a prescribed thickness, and a step S14 of forming a bonding terminal on an electrode pad of the electrode directly or via another conductive layer. Also, a method of manufacturing a semiconductor device consists of a step S15 of connecting the bonding terminal of the obtained semiconductor chip to a conductive pattern of a wiring board having the conductive pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an ultra-thin semiconductor device chip applied in the field of manufacturing electronic equipment, and a method for flip-chip mounting the semiconductor device chip on a printed wiring board. It relates to a manufacturing method.

[0002]

2. Description of the Related Art In recent years, electronic devices have been increasingly miniaturized, and in order to further reduce the size of electronic devices, it has become an important issue how to increase the mounting density. In order to reduce the size of electronic devices on which a semiconductor integrated circuit (semiconductor IC) is mounted, an LSI bare chip is directly mounted on a mounting substrate as an alternative to the conventional package mounting technology using bonding wires and lead frames. Research and development of a wireless bonding method for connecting to the conductor pattern of the above is active.

In particular, all the electrode portions and the corresponding connection terminals are formed on the device forming surface side of the device chip, and the device forming surface is turned downward, and the electrode pads of the electrode portions and the conductors of the mounting board are mounted. A method of directly connecting a pattern is called a flip-chip bonding method, and its use is widely expanded for mounting a hybrid IC, a large-sized computer, and the like because the assembly process can be rationalized.

As a method of mounting such a flip-chip type semiconductor device, for example, a solder bump is formed on an aluminum electrode pad of a semiconductor LSI, and each connection terminal of the semiconductor LSI chip is brought into contact with the solder bump. Then, there is a method of connecting this directly to the conductor pattern of the printed wiring board.

However, this method mainly aims at miniaturization in the two-dimensional direction, and there is a limit to thinning. For example, an IC card, a mobile phone, a PDA (Per
In portable electronic devices such as a personal digital assistant, etc., it is necessary to further reduce the device mounting space.

[0006] Therefore, in addition to the two-dimensional miniaturization which has been mainly pursued until now, it is necessary to establish a mounting technology of a semiconductor device which can further reduce the thickness in the height direction.

As one of the mounting techniques for such a thinned semiconductor device component, a protective tape is attached to the surface of a silicon wafer after forming an LSI, and a method such as mechanical grinding or chemical mechanical polishing is applied to the back surface of the wafer. Thinning may be considered.

Hereinafter, an example of manufacturing a semiconductor device by this method will be described with reference to the drawings. FIG. 11 shows (S31) an LSI / aluminum electrode pad forming step, (S32) an under bump metal layer forming step,
It is a manufacturing process flowchart figure by the conventional method which consists of 33) solder bump formation process, (S34) wafer thinning process, and (S35) flip chip mounting process.

First, for example, a silicon semiconductor wafer 3
An LSI (not shown) is formed on the surface layer 01 of FIG. Next, an aluminum wiring layer (not shown) for connecting each element constituting the LSI and an aluminum electrode pad (Al electrode pad) 302 as an external connection terminal are formed. Further, after covering the entire surface of the substrate (the semiconductor wafer on which the LSI, the aluminum wiring layer, and the Al electrode pad are formed) with a surface protective film 304 made of, for example, silicon nitride or polyimide, the surface protective film 304 on the Al electrode pad 302 is selected. Then, the surface of the Al electrode pad 302 is exposed (S31). As described above, FIG.
The structure shown in FIG.

Next, as shown in FIG.
A metal multilayer film made of Cr, Cu, Au, or the like, a so-called BLM (Ball Limiti) is formed by, for example, a sputtering method so as to cover the exposed portion of the electrode pad 302.
ng Metal) film 303 is formed (S32). The BLM layer 303 is called an under bump metal layer, and is formed for the purpose of improving the adhesive strength between the solder bump and the aluminum electrode, preventing the formation of an intermetallic compound due to diffusion, and the like.

Next, as shown in FIG.
A resist film 305 having an opening in the region of the film 303 is formed, and as shown in FIG.
Upper surface protection film 304 and BLM film 3 in opening C
03, a solder vapor deposition film 306 ′ is formed. afterwards,
As shown in FIG. 13E, unnecessary portions of the solder-deposited film 306 ′ are removed by lift-off of the resist film 305 to form a solder-deposited film 306 ′ having a desired pattern.

[0013] Subsequently, as shown in FIG. 13 (f), a heat treatment is applied to melt the solder vapor deposition film 306 ′, thereby forming a substantially spherical solder bump 306 based on the surface tension of the molten solder. (S33). In this example, the solder deposition film 306 'is formed by a so-called lift-off method, but another method may be used.

Then, the obtained semiconductor wafer (hereinafter, referred to as
Simply referred to as a "wafer." ) Is performed as follows. That is, first, FIG.
As shown in (a), the surface of the wafer (solder bump 3
A surface protection tape 312 composed of an adhesive layer 313 and a tape base material 314 is attached to the surface (the surface on which No. 06 is formed).

Next, as shown in FIG. 14B, the opposite surface (back surface) of the wafer to which the surface protection tape 312 has been attached is set in a mechanical grinding device, and the back surface of the wafer is ground. An example of specific conditions of the mechanical grinding is shown below.

Wheel speed: 150 μm / min Wheel rotation speed: 2500 rpm Wafer cutting allowance: about 225 μm Wafer thickness after grinding: 400 μm

At this time, damage due to the grinding of the back surface of the wafer, such as shallow grinding flaws and hairline cracks, is newly added, and this grinding damage causes a decrease in the mechanical strength of the wafer. .

For this reason, the CMP (Ch)
electrical Mechanical Polish
ng) A finishing process is performed by polishing using a device. The following is an example of specific conditions for this polishing.

Wafer rotation speed: 80 rpm Polishing pressure: 400 g / cm ² Oscillation speed: 2 mm / sec Slurry supply speed: 40 ml / min Shaving allowance: 10 μm

As a result, as shown in FIG. 14C, grinding flaws formed on the back surface of the wafer can be removed by grinding, and the mechanical strength of the wafer can be improved. 14A and 14C, the aluminum wiring layer on the wafer surface, the Al electrode pad 302, the surface protection film 304, and the solder bump 30
6 is omitted.

Thereafter, the surface protection tape 312 is peeled off from the obtained wafer, and dicing is performed to cut out a semiconductor device chip.
By connecting (flip-chip mounting) the solder balls 306 of (d) to the Cu lands 308 of the printed wiring board 310, a thinned semiconductor device as shown in FIG. Can be.

[0021]

As described above, a conventional semiconductor device chip having bump electrodes formed thereon is flip-chip mounted on a printed wiring board by using the manufacturing technique proposed by the present inventors. Various electronic devices can be reduced in size and weight as compared with the case where a device packaged with a mold resin is mounted.

However, according to the above-described method, when the semiconductor device chip with the solder bump electrodes is subjected to the above-mentioned thinning processing, the wafer surface is protected to protect the device on the wafer surface. Although it is necessary to cover with a tape, there is a problem that sufficient adhesion strength cannot be obtained between the surface protection tape 312 and the device chip with the solder bump electrodes.

That is, as shown in FIG. 14B, since bump electrodes are formed on the wafer surface, the steps on the wafer surface are steep, and the surface protection tape 312
The adhesion strength between the surface protection tape 312 and the device chip with the solder bump electrode is not sufficiently obtained, and the surface protection tape 312 is peeled off during the grinding process or the polishing process. In some cases, water or a polishing solvent may enter through gaps between the gaps and damage devices on the wafer surface.

In order to solve such a problem, it is conceivable to reduce the height of the solder bump. However, in order to secure the bonding strength and connection reliability after mounting the flip chip,
The height of the solder bump cannot be reduced below a certain level.

Therefore, it is necessary to solve these problems and establish means for stably manufacturing a thin semiconductor device chip with solder bump electrodes.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor device chip capable of realizing ultra-thin mounting of a semiconductor device with high reliability, and a method of connecting the semiconductor device chip to a wiring board. And a method of manufacturing a semiconductor device to be flip-chip mounted on the semiconductor device.

[0027]

Means for Solving the Problems In order to solve the above problems,
The present invention is, first, a step of thinning a surface of a semiconductor wafer having an electrode portion opposite to a surface on which the electrode portion is formed so that the semiconductor wafer has a predetermined thickness; Provided is a method for manufacturing a semiconductor device chip including a step of forming a bonding terminal directly or via another conductive layer on an electrode pad.

In the first aspect, the step of thinning the semiconductor wafer to have a predetermined thickness preferably includes the step of reducing the thickness of the semiconductor wafer to 50 μm to 40 μm.
And a step of thinning to a thickness of 0 μm.

In the first aspect of the present invention, the bonding terminals include a solder ball bump, an Au stud bump,
Examples of bonding means such as an i / Au plated bump, an anisotropic conductive film, and a conductive paste can be given. Of these,
In the present invention, it is preferable to form solder ball bumps.

In the first invention, the electrode pad is formed before the step of thinning the semiconductor wafer or after the step of thinning the semiconductor wafer and before the step of forming a bonding terminal. It is preferable that the method further includes a step of forming an under bump metal layer as the other conductive layer.

In the step of thinning the semiconductor wafer to have a predetermined thickness, preferably, the surface of the semiconductor wafer opposite to the surface on which the electrode portion is formed is formed by a mechanical grinding method or a chemical grinding method. A step of thinning the semiconductor wafer to a predetermined thickness by any one of a mechanical polishing method and an etching method.

Here, the mechanical grinding method refers to a thinning technique for grinding the back surface of a wafer by mechanical grinding (grinding) using a mechanical grinding apparatus, and the chemical mechanical polishing method refers to a CMP method. A thinning technology for polishing the back surface of a wafer using an apparatus. The etching method refers to a thinning technique in which the back surface of a wafer is wet-etched with an etchant or dry-etched with an etching gas using an etching apparatus.

Further, the present invention provides, secondly, a step of forming a wiring pattern for electrode pad rearrangement on an electrode pad of the electrode portion of a semiconductor wafer having an electrode portion; A step of forming a protective film, a step of forming an opening reaching the electrode pad in the surface protective film, and a step of forming the semiconductor wafer on a surface opposite to a surface on which the electrode portion is formed by the semiconductor. Provided is a method for manufacturing a semiconductor device chip, comprising: a step of thinning a wafer so as to have a predetermined thickness; and a step of forming bonding terminals on the wiring pattern directly or through another conductive layer. .

The second invention is characterized in that the back surface of the wafer is thinned before forming the bonding terminals.
However, the present invention is different from the first embodiment in that a step of forming a wiring pattern for rewiring the electrode pads from the electrode pads on the wafer to a position where the bonding terminals can be formed is provided.

In the second aspect, the step of thinning the semiconductor wafer so as to have a predetermined thickness preferably includes the step of reducing the thickness of the semiconductor wafer to 50 μm to 40 μm.
And a step of thinning to a thickness of 0 μm.

In the second aspect of the present invention, examples of the bonding terminals include bonding means such as solder ball bumps, Au stud bumps, Ni / Au plated bumps, anisotropic conductive films, and conductive pastes. Although it is possible, it is preferable to form solder ball bumps.

In the second invention, the bonding terminal is formed after the step of forming the opening, before the step of thinning the semiconductor wafer, or after the step of thinning the semiconductor wafer. It is preferable that the method further includes a step of forming an under bump metal layer on the electrode pad before the step of forming the under bump metal layer.

In the step of thinning the semiconductor wafer to a predetermined thickness, the surface of the semiconductor wafer opposite to the surface on which the electrode portions are formed is formed by mechanical grinding, chemical mechanical polishing, or the like. It is preferable that the method further includes a step of thinning the semiconductor wafer to have a predetermined thickness by any one of a method selected from an etching method and an etching method.

Further, in the present invention, thirdly, the surface of the semiconductor wafer having the electrode portion opposite to the surface on which the electrode portion is formed is thinned so that the semiconductor wafer has a predetermined thickness. A step of obtaining a semiconductor device chip by forming a bonding terminal directly or via another conductive layer on the electrode pad of the electrode portion, and the bonding terminal of the obtained semiconductor device chip, and a conductor Provided is a method for manufacturing a semiconductor device, comprising a step of connecting a wiring board having a pattern with the conductor pattern.

That is, the third invention provides a method of manufacturing a semiconductor device, comprising the step of directly connecting the bonding terminal of the semiconductor device chip obtained by the first invention to the conductor pattern of the wiring board having the conductor pattern. Is the way.

Still further, the present invention fourthly provides a semiconductor wafer having an electrode portion on an electrode pad of the electrode portion.
Forming a wiring pattern for electrode pad rearrangement, forming a surface protection film on the wiring pattern, forming an opening reaching the electrode pad in the surface protection film; A step of thinning the surface of the semiconductor wafer opposite to the surface on which the electrode portions are formed so that the semiconductor wafer has a predetermined thickness, and directly or other conductive layers on the wiring pattern. A step of obtaining a semiconductor device chip by forming a bonding terminal, and a step of connecting the bonding terminal of the obtained semiconductor device chip to the conductor pattern of a wiring board having a conductor pattern. A manufacturing method is provided.

That is, the fourth invention is directed to a semiconductor device having a step of directly connecting the bonding terminal of the semiconductor device chip obtained by the first invention to the conductor pattern of a wiring board having the conductor pattern. It is a manufacturing method.

In order to reduce the thickness of a semiconductor device chip, it is efficient to reduce the thickness of the silicon wafer after forming the LSI. Further, the thinner the wafer, the more easily the wafer is broken. Therefore, it is desirable to perform the thinning process in the final step of the wafer.

However, when the back surface of the semiconductor device wafer is thinned while the bonding terminals such as solder bumps for flip-chip mounting are formed on the front surface, the unevenness of the wafer surface becomes steep, and the surface protection tape is formed. Sufficient adhesion strength cannot be obtained between the semiconductor wafer and the bonding terminal. Therefore, during the grinding or polishing process, the surface protection tape peels off, or water or polishing solvent enters through the gap formed between the surface protection tape and the wafer surface, damaging the devices on the wafer surface. Problems often occur.

Accordingly, the present inventor has conducted intensive studies on the manufacturing technology of a thin semiconductor device chip with a junction terminal. During the lithographic processing, it was concluded that it was technically very difficult to completely protect the semiconductor devices on the wafer surface, and intensive studies were made on measures for improvement.

As a result, after the electrode pads are formed on the semiconductor wafer, preferably, a pattern of an under-bump metal layer serving as a base of a bump electrode or an electrode rewiring pattern is formed on the electrode pads, and then the bonding is performed. It has been found that thinning is effective before forming the terminal, and the first and second inventions have been completed.

That is, the surface of the wafer after the formation of the electrode pads or the pattern of the under-bump metal layer, or the formation of the electrode rewiring pattern is relatively flat without large projections such as bonding terminals. The protective tape can be satisfactorily adhered to the wafer surface.

Therefore, when the back surface of the wafer is thinned by a grinding process or a polishing process, the surface protection tape is peeled off, or water or a polishing solvent enters through a gap between the surface protection tape and the wafer surface. No damage to surface devices.

In the case where an under bump metal layer serving as a base of the bonding terminal is formed, the outermost surface of the under bump metal layer is usually made of Au which is resistant to corrosion and chemically stable.
Therefore, damage to the device surface when performing thinning of the back surface of the semiconductor wafer can be greatly reduced.

Therefore, according to the first and second aspects of the present invention, after the formation of the electrode pads or the pattern of the under-bump metal layer, or after the re-wiring of the electrodes, and before the formation of the bonding terminals, the back surface of the wafer is thinned. By doing so, a high-performance, highly-reliable semiconductor device chip with reduced size and weight can be obtained.

Further, according to the second aspect of the present invention, a semiconductor device is provided in which a contact terminal with an adjacent joint terminal is prevented while maintaining a predetermined size of the joint terminal, and an ultra-thin wafer is realized. Chips can be manufactured.

According to the third and fourth aspects of the present invention, a chip is cut out from the thin semiconductor device wafer with junction terminals obtained in the first or second aspect of the invention by dicing, and this is used as a semiconductor device chip. By connecting the bonding terminal of the semiconductor device chip and the conductor pattern of the wiring board having the conductor pattern in a bare chip state without assembling a package using a mold resin, ultra-thin mounting of the semiconductor device can be achieved. This makes it possible to further reduce the size and weight of the final electronic device product set.

[0053]

Next, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the content shown below is just one embodiment, and does not depart from the gist of the present invention, such as the type of semiconductor wafer to be used, the structure of the semiconductor wafer, the type of bonding terminal, the processing apparatus, the process conditions, and the type of wiring board. Selection and change can be appropriately made within the range.

First Embodiment In the present embodiment, the first and third inventions are applied to the manufacture of a semiconductor device. FIG. 1 shows (S
11) LSI / aluminum electrode pad forming step, (S
12 is a manufacturing process flowchart of the semiconductor device manufacturing method according to the present embodiment, which includes an under bump metal layer forming process, (S13) a wafer thinning process, (S14) a bump electrode forming process, and (S15) a mounting process. .
FIG. 2A is a structural cross-sectional view of a semiconductor device chip obtained according to the present embodiment, and FIG. 2B is a semiconductor device.

The semiconductor device chip shown in FIG. 2A has a semiconductor wafer 10 on which an LSI (not shown) is formed.
1 and on the wafer 101 via an insulating film 102,
An electrode portion in which electrode pads 103 electrically connected to the LSI are regularly arranged; an under-bump metal layer 104 formed on the electrode pad; and an insulating film 102 formed on the under-bump metal layer 104 It has a surface protection film 105 having an opening and a bonding terminal (solder bump electrode) 106 formed on the under bump metal layer 104 and bonded to a conductor pattern of a wiring board.

Further, the semiconductor device shown in FIG. 2B has a junction terminal 106 portion of a semiconductor device chip shown in FIG. 2A and a wiring board (for example, a printed wiring board).
The conductor pattern 110 (for example, Cu land) 108 is bonded (so-called flip chip mounting), and the bonding portion is fixed with a sealing resin 109.

Hereinafter, an example of manufacturing the semiconductor device chip and the semiconductor device shown in FIG. 2 will be described with reference to the drawings. First, as shown in FIG. 3A, for example, an LSI (not shown) is formed on the surface layer of the silicon semiconductor wafer 101. Next, an aluminum wiring layer (not shown) for connecting each element constituting the LSI and an electrode pad (for example, an Al electrode pad) 103 as an external connection terminal are formed (S11). Further, the substrate (LSI,
After the entire surface of the semiconductor wafer on which the aluminum wiring layer and the electrode pads are formed) is covered with an insulating film 102 made of, for example, silicon nitride, a surface protective film 105 made of polyimide or the like is further formed thereon. Pad 10
The opening A is formed on the surface of the electrode pad 103 by selectively removing the insulating film 102 and the surface protection film 105 on the third electrode 3.

Next, the opening A of the Al electrode pad 103 is formed.
To cover the under bump metal layer [BLM (Ba
11 Limiting Metal) film. ] 104 is formed (S12). The under bump metal layer 104 is formed, for example, by forming a resist pattern 111 on the surface protection film 105 as shown in FIG. 2B and etching the opening A by etching as shown in FIG. To provide a tapered shape (pre-deposition treatment)
As shown in FIG. 3D, a resist is formed on the resist 111 and the Al electrode pad 103 by, for example, a sputtering method.
A metal multilayer film made of r, Cu, Au, or the like is sequentially laminated, and then, as shown in FIG.

The under-bump metal layer 104 is formed for the purpose of improving the bonding strength between the bonding terminal (solder bump) and the aluminum electrode and preventing the formation of intermetallic compounds due to diffusion.

Next, the back surface grinding (back grinding) of the wafer 101 thus obtained (hereinafter simply referred to as “wafer”) is performed as follows. First, as shown in FIG. 4A, a surface composed of an adhesive layer 113 and a tape base layer 114 is formed on the surface of the wafer 101 (the surface on which the Al electrode pad and the under bump metal layer are formed). The protection tape 112 is attached. FIG. 4 (b)
As is clear from FIG. 7, since there are no large protrusions such as bonding terminals on the semiconductor wafer, the surface protection tape 112 can be closely attached to a relatively flat surface. 4A and 4C, the illustration of the aluminum wiring layer on the surface of the wafer 101, the electrode pads 103, the under bump metal layer 104, the surface protection film 105, and the like is omitted.

Next, as shown in FIG. 4C, the opposite surface (back surface) of the wafer 101 to which the surface protection tape 112 has been attached is set in the mechanical grinding device 1 as shown in FIG. The back surface grinding of the wafer 101 is performed. That is, the wafer 101 is set on the turntable 12 with the back surface of the wafer facing upward, and the grindstone 11 is rotated with the rotation direction of the turntable 12 while rotating the turntable 12 (this rotation speed is the grindstone feed speed). Is to grind the back surface of the wafer 101 by rotating in the opposite direction (the number of rotations of the grindstone).

An example of specific conditions of the mechanical grinding is as follows. Wheel feed speed: 150 μm / min Wheel rotation speed: 2500 rpm Wafer cutting allowance: about 525 μm Wafer thickness after grinding: 110 μm

By grinding the back surface of the wafer 101,
Scratches B (see FIG. 4A) formed on the back surface of the wafer by the previous steps can be removed, but damage due to this back surface grinding, for example, shallow grinding flaws and hairline cracks are newly added, Since the grinding damage causes a decrease in the mechanical strength of the wafer 101, it is necessary to remove the grinding damage.

For this reason, a CMP (Chemical Mechanical) as shown in FIG.
(Cal Polishing) Finishing processing by polishing using the apparatus 2 is performed. That is, wafer 1
01 is set on the wafer carrier 21 with the back surface of the wafer 101 facing down, and polishing polishing of the back surface of the wafer 101 is performed while applying a constant pressure using the polishing cloth 23 and the polishing slurry 22 set on the surface plate 24. Do.

One example of specific conditions for this polishing is as follows. Wafer rotation speed: 80 rpm Rotation speed: 80 rpm Polishing pressure: 400 g / cm ² Oscillation speed: 2 mm / sec Slurry supply speed: 40 ml / min Cutting allowance: 10 μm

As a result, as shown in FIG. 4C, the grinding scratches formed on the back surface of the wafer 101 were removed, the wafer was thinned to a thickness of 100 μm, and the mechanical strength was improved. 101 can be obtained (S13).

In the present embodiment, the final wafer thickness after the wafer back surface grinding is set to be about 100 μm. However, by appropriately setting the conditions of the mechanical grinding and the chemical mechanical polishing, the wafer thickness can be reduced. The thickness can be set freely. Wafer thickness after grinding is 400 μm
Hereinafter, it is preferably set to a value of about 50 μm to 200 μm. If the thickness is 400 μm or more, the effect of the thinning process is poor. If the thickness is 50 μm or less, the mechanical strength of the wafer itself is insufficient, and the wafer is liable to be broken.

Next, as shown in FIG. 7F, after removing the surface protection tape 112, the under bump metal film 1 is removed.
Then, a resist film 115 having an opening C is formed in the region 04, and as shown in FIG.
Then, a solder vapor deposition film 106 ′ is vapor-deposited on the entire inside of the opening C.

Thereafter, as shown in FIG. 7 (h), an unnecessary portion of the solder deposited film 106 'is removed by lift-off of the resist film 115, and a desired pattern of the solder deposited film 106' is formed.

Subsequently, as shown in FIG. 7 (i), a substantially spherical solder bump 106 can be formed based on the surface tension of the molten solder by applying heat treatment to the solder vapor-deposited film 106 'and melting it. Yes (S14).

In the present embodiment, the solder bumps are formed by a method of solder vapor deposition and lift-off, but other methods such as a solder paste printing method, a solder ball method, a plating method, a fine punching method, a solder injection method, A bump electrode can be formed by various known bump forming methods such as a bonding method (for example, “Electronic Materials”, September 1996, p.
p34-38 etc.).

Thereafter, the obtained wafer 101 is diced and cut out as semiconductor device chips. In this manner, the semiconductor device chip of the present embodiment, which has been thinned as shown in FIG. 2A, can be obtained.

Next, the solder balls 106 of the semiconductor device chip and the conductor patterns (for example, Cu lands) 108 of the printed wiring board 110 are joined (flip chip mounting), as shown in FIG. Semiconductor devices can be manufactured. The conductor pattern 108 is formed on a wiring board by Cu, Al, Au,
It can be formed from metals such as W and alloys thereof.

In the semiconductor device chip and the semiconductor device of this embodiment, ultra-thin processing with a wafer thickness of about 100 μm is realized.
For example, it can be mounted on portable electronic devices such as an IC card, a mobile phone, a PDA, etc., and can greatly contribute to the realization of small and light electronic devices.

According to the first embodiment, when thinning the back surface of the wafer by grinding or polishing, the surface protection tape is peeled off or water or polishing solvent is removed from the gap between the surface protection tape and the wafer surface. Does not penetrate and damage devices on the wafer surface.

The solder bumps 106 serving as bonding terminals are provided.
When the under-bump metal layer 104 is formed as an underlayer, the outermost surface of the under-bump metal layer 104 is made of a corrosion-resistant metal such as Au which is resistant to corrosion and chemically stable. Damage to the device surface when thinning the back surface of the wafer can be significantly reduced.

Therefore, according to the present embodiment, after the formation of the electrode pads 103 or the formation of the pattern of the under-bump metal layer 104, the back surface of the wafer is subjected to a thinning process, thereby realizing a compact and lightweight high performance. Thus, a highly reliable semiconductor device chip can be obtained.

Further, according to the second aspect of the present invention, a semiconductor device in which contact with an adjacent joint terminal is prevented while maintaining a joint terminal of a predetermined height, and an ultra-thin wafer is achieved. Chips can be manufactured.

Further, the obtained thin semiconductor device chip with bonding terminals (solder bump electrodes) is formed, and in a bare chip state without assembling a package using a mold resin, the bonding terminals of the semiconductor device chip and a wiring having a conductor pattern are formed. By directly connecting the conductor pattern to the substrate, ultra-thin mounting of the semiconductor device becomes possible, and the product set of the final electronic device can be further reduced in size and weight.

Second Embodiment In this embodiment, the second and fourth inventions of the present application are applied to the manufacture of a semiconductor device chip and a semiconductor device, and solder bumps of a desired size are brought into contact with each other. To place them on the board regularly,
The back surface of the semiconductor wafer in a state where the electrode pads are rearranged by the under bump metal from the electrode pads of the LSI is thinned by mechanical grinding and etching to obtain a thin semiconductor device chip with bonding terminals. This is an example of flip-chip mounting on a printed wiring board.

FIG. 8 shows (S21) an LSI / electrode pad formation step, (S22) an electrode pad rearrangement step, and (S23).
Under bump metal layer forming step, (S24) wafer thinning processing step, (S25) bump electrode forming step, (S24)
26) A manufacturing process flowchart of this embodiment including a mounting process is shown.

FIG. 9G is a structural sectional view of a semiconductor device chip obtained according to the present embodiment. Less than,
A semiconductor device chip and a method of manufacturing a semiconductor device according to the present embodiment will be described with reference to the drawings.

First, as shown in FIG. 9A, an Al electrode pad 202 connected to an LSI (not shown) formed on a semiconductor wafer 201 is formed (S21).

Then, from the Al electrode pad 202, the under bump metal (Cr / Cu / Au
The Al electrode pad 202 is rearranged by using a stacked body composed of). This rearrangement is performed as follows.

That is, first, as shown in FIG. 9B, for example, CVD (Chemical Vapor Depo)
After a silicon nitride film 203 is formed on the entire surface by a (sition) method, a first-layer polyimide film 204 is formed by, for example, a spin coat method, and is formed on the Al electrode pad 202 by a photolithography and etching technique. Open.

Next, as shown in FIG. 9C, a resist film 205 having a predetermined rewiring pattern is formed.
Patterning for rearrangement of the Al electrode 202;
For example, Cr, Cu and Au (206) are sequentially stacked in the resist film 205 and the opening D by a vacuum deposition method.

Next, as shown in FIG. 9D, the resist film 205 is removed, and an extra under-bump metal 206 on the resist film 205 is removed, so that the Al electrode pad 202 with a predetermined under-bump metal is formed. Is formed.

Thereafter, as shown in FIG. 9E, a second-layer polyimide film 207 is formed by, for example, a spin coating method, and a solder bump electrode formation region is opened.

Subsequently, as shown in FIG. 4A, a surface protection tape 21 is
2, the wafer 201 was set in a mechanical grinding device as shown in FIG. 5, and the back surface of the semiconductor wafer was ground (back-ground) in the same manner as in the first embodiment. An example of the grinding conditions at this time is shown below.

Wheel feed speed: 150 μm / min Wheel rotation speed: 2500 rpm Wafer thickness after grinding: 150 μm Cutting allowance: about 475 μm

By this grinding, the silicon wafer was thinned to a thickness of about 150 μm while removing flaws formed on the back surface of the silicon wafer. However, after the grinding, many scratches are inevitably formed on the back surface of the wafer in many steps so far.

Then, the obtained thin semiconductor wafer 20
1 is etched by, for example, a known spin etching apparatus 3 including a chamber 31, a dispenser 32, an exhaust pipe 33, and the like as shown in FIG. That is, the wafer 201 is set in the process chamber 31 with the back surface of the wafer facing upward, and a dispenser (Dispe
nser) 32, while performing the wet etching while supplying the etchant, to perform the finishing process on the back surface of the wafer.

The etching of the back surface of the wafer can be performed, for example, under the following conditions. Wafer rotation speed: 2000 rpm Etching solution composition: HF: HNO ₃ = 1: 9 Etching solution supply amount: 40 l / min Wafer shaving allowance: 50 μm

As a result, fine grinding damage newly formed in the grinding process of the back surface of the wafer 201 is removed, and the thickness is reduced to 100 μm as in the case of the first embodiment.
m, the mechanical strength of the semiconductor wafer that has been thinned to m.

In the present embodiment, the thickness of the wafer after grinding the back surface of the wafer is set to be about 100 μm. However, the thickness of the wafer can be freely set by appropriately setting the conditions of mechanical grinding and etching. can do. The thickness of the wafer after grinding is set to a value of 400 μm or less, preferably about 50 μm to 200 μm. If the thickness is 400 μm or more, the effect of the thinning process is poor. If the thickness is 50 μm or less, the mechanical strength of the wafer itself is insufficient, and the wafer is liable to be broken.

Also in this embodiment, the surface (surface) on the side of the semiconductor wafer on which the electrode pads 203 and the like are formed when the surface protection tape 212 is adhered has no large projections and is relatively flat. It has a structure. Therefore, the surface protection tape 212 can be attached to the wafer 201 without any gap.
It can be attached to the surface, and in the grinding and etching processes, the surface protection tape 212 is peeled off, or water or an etching solution enters through a gap between the surface protection tape 212 and the surface of the wafer 201, thereby damaging devices on the surface of the wafer 201. Without giving, the semiconductor wafer can be thinned.

Next, as shown in FIG. 9G, a solder ball 208 is formed by a ball transfer method on the opening of the second polyimide film 207 of the rewiring pattern on the thinned semiconductor wafer. Accordingly, a semiconductor wafer having the rearranged solder bump electrodes 208 can be manufactured.

In this embodiment, the solder bumps are formed by the solder ball method (solder ball transfer method). Other, for example, solder paste printing method, plating method, fine punching method, solder injection method,
Bump electrodes can be formed by various known bump forming methods such as a ball bonding method (for example, see “Electronic Materials”, September 1996, pp. 34 to 38).

Thereafter, the obtained semiconductor device wafer is diced and cut out as semiconductor device chips, and the solder balls 208 of the semiconductor device chips are cut out.
By connecting (flip chip mounting) to a conductor pattern (for example, Cu land) of a printed wiring board,
A semiconductor device having a structure similar to that shown in FIG. 2B can be manufactured. The conductor pattern can be formed on a wiring board from a metal such as Cu, Al, Au, W, or an alloy thereof.

The semiconductor device having the ultra-thin package obtained as described above is ultimately used for various electronic devices,
For example, it can be mounted on portable electronic devices such as an IC card, a mobile phone, a PDA, etc., and can greatly contribute to the realization of small and light electronic devices.

In the second embodiment, after the rewiring pattern of the electrode pads is formed, the back surface of the wafer is thinned. At the stage after the formation of the rewiring pattern of the electrode pads, the surface of the wafer 201 has no large protrusions and is kept relatively flat.
Good contact with one surface can be achieved. Therefore, when thinning the back surface of the wafer 201 by a grinding process or a polishing process, the surface protection tape 212 is peeled off, or water or a polishing solvent enters through a gap between the surface protection tape 212 and the wafer 201, and the wafer There is no damage to the device on the surface of 201.

Also, since the outermost layer of the rewiring pattern is usually made of a corrosion-resistant metal such as Au which is resistant to corrosion and chemically stable, the device surface when thinning the back surface of the semiconductor wafer is processed. Can greatly reduce damage.

Further, according to the second embodiment, a semiconductor device in which contact with an adjacent bump is prevented while maintaining a predetermined size of a bump electrode, and an ultra-thin wafer is achieved. Chips can be manufactured.

Therefore, according to the present embodiment, it is possible to obtain a high-performance and highly-reliable semiconductor device chip that is reduced in size and weight.

Further, according to the present embodiment, the semiconductor device can be flip-chip mounted on the printed wiring board in a bare chip state without assembling a package using a molding resin from the thin semiconductor device chip with the bonding terminals manufactured. The device can be mounted in an ultra-thin film, and the product set of the final electronic device can be further reduced in size and weight.

[0106]

As described above, the first aspect of the present invention is described above.
According to the second aspect, at the stage after the formation of the electrode pad, the pattern of the under-bump metal layer, or the formation of the electrode rewiring pattern, the wafer surface has no large protrusions and is kept relatively flat. As a result, the surface protection tape can be brought into close contact with the wafer surface.

Therefore, when the back surface of the wafer is thinned by a grinding process or a polishing process, the surface protection tape is peeled off, or water or a polishing solvent intrudes from a gap between the surface protection tape and the wafer, and the wafer surface is removed. No damage to any device.

When an under-bump metal layer serving as a base of a bonding terminal is formed or a rewiring pattern of an electrode pad is formed, the outermost surfaces of these layers are usually resistant to corrosion and chemically. Since it is made of a stable corrosion-resistant metal such as Au, it is possible to greatly reduce damage to the device surface when thinning the back surface of the semiconductor wafer.

Further, according to the second aspect of the present invention, the contact with the adjacent bonding terminal (bump electrode) is prevented while maintaining the predetermined size of the bonding terminal (bump electrode), and the ultra-thin wafer is formed. It is possible to manufacture a semiconductor device chip in which a mold is achieved.

Therefore, according to the first and second aspects of the present invention, after the formation of the electrode pad, the formation of the pattern of the under bump metal layer, or the rewiring of the electrode, the back surface of the semiconductor wafer is subjected to a thinning process, thereby achieving a small size. Thus, a high-performance and highly-reliable semiconductor device chip with reduced size and weight can be obtained.

According to the third and fourth inventions, a semiconductor device chip is cut out from the thin semiconductor device wafer with bump electrodes manufactured in the first or second invention by dicing, and a package using a mold resin is prepared. By bonding the bonding terminals of the semiconductor device chip and the conductor pattern of the wiring board having the conductor pattern directly in a bare chip state without assembling the semiconductor device, it becomes possible to mount an ultra-thin film of the semiconductor device. Can be further reduced in size and weight.

Therefore, the present invention is extremely effective for the manufacture of future semiconductor device devices requiring high performance, high reliability, small size and light weight.

[Brief description of the drawings]

FIG. 1 is a flowchart of a manufacturing process of a semiconductor device of the present invention.

FIG. 2 is a structural sectional view of a semiconductor device chip and a semiconductor device obtained by a method of manufacturing a semiconductor device chip and a semiconductor device according to the present invention.

FIG. 3 is a sectional view of a main step of the method for manufacturing a semiconductor device chip of the present invention.

FIG. 4 is a process sectional view of a wafer back surface grinding process in the method of manufacturing a semiconductor device chip according to the present invention.

FIG. 5 is a conceptual diagram of mechanical grinding and polishing using a mechanical grinding device in a wafer back surface grinding step of the method for manufacturing a semiconductor device chip of the present invention.

FIG. 6 is a conceptual diagram of polishing and polishing using a chemical mechanical polishing apparatus in a wafer back surface grinding step of the method for manufacturing a semiconductor device chip of the present invention.

FIG. 7 is a sectional view showing main steps of a method for manufacturing a semiconductor device chip according to the present invention.

FIG. 8 is a flowchart of a manufacturing process of the semiconductor device of the present invention.

FIG. 9 is a sectional view of a main step of the method for manufacturing a semiconductor device chip of the present invention.

FIG. 10 is a conceptual diagram of etching using a spin etching apparatus in a wafer back surface grinding step of the method for manufacturing a semiconductor device chip of the present invention.

FIG. 11 is a flowchart of a conventional semiconductor device manufacturing process.

FIG. 12 is a sectional view of a main step in a conventional method for manufacturing a semiconductor device chip.

FIG. 13 is a sectional view of a main step in a conventional method for manufacturing a semiconductor device chip.

FIG. 14 is a process cross-sectional view of a wafer back surface grinding process in a conventional method for manufacturing a semiconductor device chip.

FIG. 15 is a structural sectional view of a semiconductor device chip and a semiconductor device obtained by a conventional method of manufacturing a semiconductor device chip and a semiconductor device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Mechanical grinding apparatus, 2 ... Chemical mechanical polishing (CMP) apparatus, 3 ... Spin etching apparatus, 11 ... Whetstone, 12 ... Rotating table, 21 ... Wafer carrier, 22 ... Polishing slurry,
23: polishing cloth, 24: platen, 31: chamber, 3
2 ... dispenser, 33 ... exhaust pipe, 101, 201,
Reference numeral 301: semiconductor wafer, 102, 203, 304 ... insulating film, 103, 202, 302 ... electrode pad, 104,
303: Under bump metal layer (BLM film), 10
5, 204, 207, 305: surface protective film, 106, 2
08, 306: joining terminal (solder bump), 106 ',
306 ': Solder deposited film, 108, 308: Conductor pattern (Cu land) of wiring board, 109, 309: Sealing resin, 110, 310 ... Wiring board, 111.115, 20
5,305 ... resist film, 112,312 ... surface protection tape, 113,313 ... adhesive layer, 114,314 ... tape base material, 206 ... most electrode wiring pattern (under bump metal), A, C, D ... opening Part, B, E: scratches on the back of the wafer

Claims (24)

[Claims] A step of thinning a surface of a semiconductor wafer having an electrode portion opposite to a surface on which the electrode portion is formed so that the semiconductor wafer has a predetermined thickness; A method for manufacturing a semiconductor device chip, comprising a step of forming a bonding terminal directly on an electrode pad or through another conductive layer. 2. The step of thinning the semiconductor wafer so as to have a predetermined thickness comprises:
The method for manufacturing a semiconductor device chip according to claim 1, further comprising a step of performing a thinning process so as to have a thickness of 0 μm to 400 μm. 3. The method of manufacturing a semiconductor device chip according to claim 1, wherein the step of forming the bonding terminal includes a step of forming a solder bump on the electrode pad directly or via another conductive layer. 4. The method for manufacturing a semiconductor device chip according to claim 1, further comprising a step of forming an under bump metal layer on said electrode pad before said step of thinning said semiconductor wafer. 5. The semiconductor according to claim 1, further comprising a step of forming an under bump metal layer on the electrode pad after the step of thinning the semiconductor wafer and before the step of forming a bonding terminal. Device chip manufacturing method. 6. The step of thinning the semiconductor wafer so as to have a predetermined thickness includes the steps of: mechanical grinding, chemical mechanical polishing, a surface opposite to a surface on which the electrode portion of the semiconductor wafer is formed. 2. The method of manufacturing a semiconductor device chip according to claim 1, further comprising a step of thinning the semiconductor wafer to have a predetermined thickness by any one of a method selected from an etching method and an etching method. 3. 7. A step of forming a wiring pattern for electrode pad rearrangement on an electrode pad of the electrode section of a semiconductor wafer having an electrode section; and a step of forming a surface protection film on the wiring pattern. A step of forming an opening reaching the electrode pad in the surface protective film; and forming a semiconductor wafer having a predetermined thickness on a surface of the semiconductor wafer opposite to a surface on which the electrode portion is formed. A method of manufacturing a semiconductor device chip, comprising: a step of thinning; and a step of forming a bonding terminal on the wiring pattern. 8. The step of thinning the semiconductor wafer so as to have a predetermined thickness comprises:
The method of manufacturing a semiconductor device chip according to claim 7, further comprising a step of performing a thinning process so as to have a thickness of 0 μm to 400 μm. 9. The method of manufacturing a semiconductor device chip according to claim 7, wherein the step of forming the bonding terminal includes a step of forming a solder bump on the electrode pad directly or via another conductive layer. 10. The method according to claim 7, further comprising a step of forming an under bump metal layer on the electrode pad after the step of forming the opening and before the step of thinning the semiconductor wafer. A method for manufacturing a semiconductor device chip. 11. The semiconductor according to claim 7, further comprising a step of forming an under bump metal layer on the electrode pad after the step of thinning the semiconductor wafer and before the step of forming a bonding terminal. Device chip manufacturing method. 12. The step of thinning the semiconductor wafer so as to have a predetermined thickness, the surface of the semiconductor wafer opposite to the surface on which the electrode portion is formed is subjected to a mechanical grinding method.
The method for manufacturing a semiconductor device chip according to claim 7, further comprising a step of thinning the semiconductor wafer to a predetermined thickness by any one of a chemical mechanical polishing method and an etching method. 13. A step of thinning a surface of a semiconductor wafer having an electrode portion opposite to a surface on which the electrode portion is formed so that the semiconductor wafer has a predetermined thickness; A step of obtaining a semiconductor device chip by forming a bonding terminal directly or via another conductive layer on the electrode pad; and a step of forming the bonding terminal of the obtained semiconductor device chip and a wiring board having a conductive pattern. A method for manufacturing a semiconductor device, comprising a step of connecting to a conductor pattern. 14. The step of thinning the semiconductor wafer so as to have a predetermined thickness,
The method for manufacturing a semiconductor device according to claim 13, further comprising a step of performing a thinning process so as to have a thickness of 50 μm to 400 μm. 15. The method of manufacturing a semiconductor device according to claim 13, wherein the step of forming the bonding terminal includes a step of forming a solder bump on the electrode pad directly or via another conductive layer. 16. The method for manufacturing a semiconductor device according to claim 13, further comprising a step of forming an under-bump metal layer on said electrode pad before said step of thinning said semiconductor wafer. 17. The semiconductor according to claim 13, further comprising a step of forming an under bump metal layer on the electrode pad after the step of thinning the semiconductor wafer and before the step of forming a joint terminal. Device manufacturing method. 18. The step of thinning the semiconductor wafer to have a predetermined thickness includes the steps of: mechanical grinding, chemical mechanical polishing, a surface opposite to a surface of the semiconductor wafer on which electrode pads are formed. The method of manufacturing a semiconductor device according to claim 13, further comprising a step of thinning the semiconductor wafer to a predetermined thickness by any one of a method selected from an etching method and an etching method. 19. A step of forming a wiring pattern for electrode pad rearrangement on an electrode pad of the electrode section of a semiconductor wafer having an electrode section, and a step of forming a surface protection film on the wiring pattern. A step of forming an opening reaching the electrode pad in the surface protective film; and forming a semiconductor wafer having a predetermined thickness on a surface of the semiconductor wafer opposite to a surface on which the electrode portion is formed. A step of forming a bonding terminal directly or via another conductive layer on the electrode pad to obtain a semiconductor device chip; and a step of forming a bonding terminal on the obtained semiconductor device chip. A method of manufacturing a semiconductor device, comprising: connecting a wiring board having a conductor pattern to the conductor pattern. 20. The step of thinning the semiconductor wafer so as to have a predetermined thickness,
20. The method of manufacturing a semiconductor device according to claim 19, further comprising a step of performing a thinning process so as to have a thickness of 50 μm to 400 μm. 21. The method of manufacturing a semiconductor device according to claim 19, wherein the step of forming the bonding terminal includes the step of forming a solder bump on the wiring pattern. 22. The method according to claim 19, further comprising a step of forming an under bump metal layer on the wiring pattern after the step of forming the opening and before the step of thinning the semiconductor wafer. A method for manufacturing a semiconductor device. 23. The semiconductor according to claim 19, further comprising a step of forming an under bump metal layer on the electrode pad after the step of thinning the semiconductor wafer and before the step of forming a bonding terminal. Device manufacturing method. 24. The step of thinning the semiconductor wafer so as to have a predetermined thickness, the surface of the semiconductor wafer opposite to the surface on which the electrode portion is formed is formed by a mechanical grinding method.
20. The method of manufacturing a semiconductor device according to claim 19, further comprising a step of reducing the thickness of the semiconductor wafer to a predetermined thickness by any one of a chemical mechanical polishing method and an etching method.