JP2002131375A - Semiconductor ic contact structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor IC contact structure suitable for testing a high frequency characteristic because its signal path is shorter than that of a conventional one, manufacturable at a low cost, and sufficiently applicable for a fine-pitch arrangement solder ball. SOLUTION: In this structure electrically connecting the solder ball 2 serving as a connection electrode of the semiconductor IC 1 to a land pattern 4 formed on a inspection circuit base board 3, contacts 5 each formed of a ring-shaped coil spring are arranged in correspondence to the respective solder balls 2, and the solder balls 2 are forcibly pressed to the contacts 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact structure for electrically connecting a semiconductor IC having solder balls as connection electrodes and an inspection device for performing an electrical inspection of the semiconductor IC.

[0002]

2. Description of the Related Art Generally, a BGA (Ball Grid) is used.
A semiconductor IC having a solder ball as a connection electrode like an Array type package, in particular, a CSP (Chip)
Size Package) is widely used because it has an advantage that a mounting area occupied on a substrate is small and high density can be achieved.

In the process of manufacturing a semiconductor IC having such solder balls, when inspecting electrical characteristics of the manufactured semiconductor IC, the semiconductor IC and an inspection circuit board serving as a test head of an inspection apparatus are required. It is necessary to make an electrical connection between them.

For this reason, conventionally, as a contact structure for electrically connecting a test circuit board to a solder ball of a semiconductor IC, for example, those shown in FIGS. 6 and 7 have been provided.

[0005] The conventional structure shown in FIG.
A pogo pin 52 as a contact pin is provided upright. The pogo pin 52 is provided with a coiled compression spring (not shown) and a plunger 52b inside a cylindrical body 52a, and an upper end of the plunger 52b protrudes outward from the cylindrical body 52a so as to be able to expand and contract. Then, the plunger 52b is connected to the solder ball 6 of the semiconductor IC 60 by the expansion and contraction of the compression spring.
1, the solder ball 61 is moved to the plunger 5.
The test circuit board 50 is electrically connected to the test circuit board 50 via the cylindrical body 2b and the cylindrical body 52a.

[0006] On the other hand, the conventional structure shown in FIG.
Clip-type contact pin 54 having spring elasticity
Is erected. That is, the contact pins 54
Is formed with a V-shaped pressing portion 54a whose upper end is branched right and left, and the pressing portion 54a
By sandwiching the solder ball 61 of C60, the solder ball 61 is electrically connected to the inspection circuit board 50 via the contact pin 54.

[0007]

However, with the conventional contact structure shown in FIGS. 6 and 7, the following problems can be pointed out.

(1) Any of the contact pins 52, 5
4, the solder ball 6 of the semiconductor IC 60 is used.
Since the signal path from No. 1 to the test circuit board 50 is long, external noise is apt to be mixed in the signal path, and the frequency characteristics are deteriorated, so that it is difficult to accurately test the high frequency characteristics.

(2) In order to provide the contact pins 52 and 54 individually corresponding to a large number of solder balls 61 arranged at a fine pitch on the semiconductor IC 60, the contact pins 52 and 54 themselves need to have a fine structure. There is. However, the conventional one has a relatively complicated pin structure,
There is a limit to the fine structure, and the contact pins 52 and 54 become extremely expensive.

(3) In the contact structure shown in FIG.
As the arrangement pitch of the solder balls 61 of the semiconductor IC 60 becomes finer, it becomes more difficult to insert each end of the pinching portion 54 a of the contact pin 54 between the pitches of the solder balls 61.

The present invention solves each of the problems pointed out in the above (1) to (3), and has a signal path shorter than that of the prior art, suitable for inspection of high frequency characteristics, and can be manufactured at a low cost. It is another object of the present invention to provide a contact structure of a semiconductor IC that can sufficiently cope with a fine arrangement pitch of solder balls.

[0012]

According to the present invention, in order to achieve the above object, a solder ball of a semiconductor IC having solder balls as connection electrodes is electrically connected to a land pattern formed on an inspection circuit board. The following configuration is employed in the contact structure of the semiconductor IC for connection.

In other words, the contact structure of the semiconductor IC according to the first aspect of the present invention is a contact element in which a coil spring is formed in a ring shape on a land pattern of an inspection circuit board, corresponding to solder balls individually. Are provided, and solder balls are pressed against these contacts.

According to a second aspect of the present invention, there is provided a contact structure for a semiconductor IC, wherein an intermediate printed board is provided between the semiconductor IC and the inspection circuit board, and solder balls and land patterns are provided on upper and lower surfaces of the intermediate printed board. And a contact formed by forming a coil spring in a ring shape corresponding to each of the contacts, and the solder ball and the land pattern are respectively pressed against these upper and lower contacts. .

According to a third aspect of the present invention, there is provided a contact structure for a semiconductor IC, wherein an elastic sheet is interposed on the back side of the inspection circuit board, and an insulating sheet is interposed between the semiconductor circuit and the front side. The sheet holds conductive contacts at positions individually corresponding to the solder balls, and is characterized in that the solder balls and the land patterns are pressed against these contacts, respectively.

The above-mentioned contact may be made of a metal ball or a metal rod.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is an exploded sectional view showing a contact structure of a semiconductor IC according to a first embodiment of the present invention.

In FIG. 1, 1 is a semiconductor IC, 2 is a solder ball as a connection electrode of the semiconductor IC 1, 3 is an inspection circuit board for transmitting an inspection signal, and 4 is a solder ball 2 on the same board 3. It is a land pattern formed corresponding to each. The solder ball 2 has, for example, a diameter of about 30 μm.
m, and are arranged at a pitch of about 80 μm.

In the first embodiment, the contacts 5 are fixed on the land patterns 4 of the inspection circuit board 3 by soldering or the like individually corresponding to the solder balls 2 of the semiconductor IC 1. As shown in FIG. 2, these contacts 5 are formed by forming a coil spring wound around, for example, an outer diameter D1 of about 10 to 20 μm in a ring shape having a diameter D2 of about 20 to 25 μm. The solder balls 2 are pressed against these contacts 5. The coil spring serving as the contact 5 is formed by winding, for example, a beryllium copper wire, a phosphor bronze wire, a piano wire, or the like, which is subjected to surface treatment with gold plating or the like.

Thus, the solder ball 2 is electrically connected to the land pattern 4 of the inspection circuit board 3 via the contact 5. Therefore, by sending a signal from the inspection apparatus main body (not shown) to the internal circuit of the semiconductor IC 1 via the land pattern 4, the contact 5, and the solder ball 2,
One test can be performed.

In the contact structure of the first embodiment, the signal path from the solder ball 2 of the semiconductor IC 1 to the inspection circuit board 3 is shorter than that of the conventional structure shown in FIGS. Suitable for inspection. Further, since the contact 5 is made of a coil spring, it has elasticity, and contacts the solder ball 2 at multiple points, so that the contact resistance is small and the contact failure is small. Therefore, an accurate inspection can be performed. Moreover, the conventional contact pins 52, 54
Since the structure is simpler than that of the above, it can be manufactured at low cost. Furthermore, even if the arrangement pitch of the solder balls 2 is fine, it is possible to sufficiently cope with such arrangement.

Embodiment 2 FIG. 3 is an exploded cross-sectional view showing a contact structure of a semiconductor IC according to Embodiment 2 of the present invention, in which parts corresponding to those of Embodiment 1 shown in FIG. Is attached.

In FIG. 3, 1 is a semiconductor IC, 2 is a solder ball as a connection electrode of the semiconductor IC, 3 is an inspection circuit board, 4 is a land formed on the same board 3 corresponding to the solder ball 2 individually. It is a pattern.

In the second embodiment, a flexible printed circuit board 7 is provided between the semiconductor IC 1 and the inspection circuit board 3. Land patterns 8 are respectively formed on the upper and lower surfaces of the intermediary printed circuit board 7 so as to correspond to the solder balls 2 and the land patterns 4, respectively. On these land patterns 8, coil springs are formed in a ring shape. Is fixed by soldering or the like. Further, the land patterns 8 above and below the intermediate printed board 7 are electrically connected to each other via through holes 9 formed in the board 7. Then, the solder balls 2 are applied to the contacts 5 on the upper side of the intermediate printed circuit board 7.
However, the land patterns 4 of the inspection circuit board 3 are pressed against the contacts 5 on the lower side of the intermediary printed circuit board 7, respectively.

As a result, the solder balls 2 are electrically connected to the land patterns 4 of the inspection circuit board 3 via the contacts 5, the land patterns 8 and the through holes 9 of the intermediary printed circuit board 7. Therefore, the semiconductor IC 1 can be inspected by sending a signal from the inspection apparatus body (not shown) to the semiconductor IC 1 via the land pattern 4, the contacts 5 on the intermediary printed circuit board 7, and the solder balls 2.

The contact structure according to the second embodiment has elasticity because the contact 5 is made of a coil spring, as in the case of the first embodiment. On the other hand, since the contact is made at multiple points, the contact resistance is small and the contact failure is small. Therefore, accurate inspection can be performed. In addition, even if the arrangement pitch of the solder balls 2 is fine, it can sufficiently cope with the arrangement pitch.

On the other hand, the contact structure of the second embodiment is slightly more complicated than that of the first embodiment, but the solder ball 2 is attached to the contact 5 for inspection of the semiconductor IC 1. If the contact 5 is worn or damaged due to frequent contact with the contact 5, it is only necessary to replace the contact 5 and the intermediate printed circuit board 7 to which the contact 5 is fixed. It is not necessary to replace everything, so that maintenance costs can be reduced.

Although the signal path from the solder ball 2 of the semiconductor IC 1 to the inspection circuit board 3 is slightly longer as compared with the case of the first embodiment, the signal path is compared with the conventional structure shown in FIGS. Since the path is extremely short, it is suitable for inspection of high frequency characteristics. In addition, since the structure is simpler than that of the related art, it can be manufactured relatively inexpensively. In the second embodiment, the intermediate printed circuit board 7
Is flexible, but it is also possible to use a thin general wiring board.

Third Embodiment FIG. 4 is an exploded cross-sectional view showing a contact structure of a semiconductor IC according to a third embodiment. Parts corresponding to those in the first embodiment shown in FIG. Is attached.

In FIG. 4, reference numeral 1 denotes a semiconductor IC, 2 denotes a solder ball as a connection electrode of the semiconductor IC, 3 denotes an inspection circuit board, and 4 denotes lands formed on the substrate 3 individually corresponding to the solder balls 2. It is a pattern.

In the third embodiment, the inspection circuit board 3 has flexibility, and an elastic sheet 10 made of rubber or the like is provided on the back side of the inspection circuit board 3. A flat plate 11 serving as a base is disposed on the back side of the plate.

On the other hand, an insulating sheet 12 made of polyester or the like is interposed between the inspection circuit board 3 and the semiconductor IC 1 at positions corresponding to the solder balls 2 individually. , A conductive metal ball 13 as a contact is held. Each of these metal balls 13 is made of, for example, iron or tungsten and has a diameter of about 50 μm, and upper and lower ends thereof are exposed from the insulating sheet 12. The solder balls 2 and the land patterns 4 are pressed against these metal balls 13 respectively.

As a result, the solder ball 2 becomes the metal ball 1
3 and electrically connected to the land pattern 4 of the inspection circuit board 3. Therefore, by sending a signal from the inspection apparatus body (not shown) to the semiconductor IC 1 via the land pattern 4, the metal balls 13, and the solder balls 2, the semiconductor I
An inspection of C1 can be performed.

In this case, even if the outer diameter of the solder ball 2 and the metal ball 13 varies, the variation of the outer diameter is absorbed by the elastic sheet 10 disposed under the inspection circuit board 3, and The solder ball 2 and the land pattern 4 are reliably electrically contacted via the ball 13. Therefore, a good electrical connection state can be maintained.

When the solder ball 2 frequently contacts the metal ball 13 for testing the semiconductor IC 1 and the metal ball 13 is worn or damaged, the metal ball 13 It is only necessary to replace the insulating sheet 12 holding this, and the maintenance cost can be reduced as compared with the case where the entirety including the inspection circuit board 3 is replaced.

In the third embodiment, the metal ball 13 is used as the conductive contact held on the insulating sheet 12, but instead, as shown in FIG. A configuration in which the conductive metal rod 14 is held by the insulating sheet 12 may be employed.

[0037]

According to the present invention, the following effects can be obtained.
The contact structure of the semiconductor IC according to the first aspect of the present invention is suitable for inspection of high-frequency characteristics because the signal path is shorter than in the prior art. In addition, since the contact made of a coil spring contacts the solder ball at multiple points, the contact resistance is small and the contact failure is reduced, so that an accurate inspection can be performed. Moreover, since the structure is simple, it can be manufactured at low cost. Furthermore, it is possible to sufficiently cope with a fine arrangement pitch of the solder balls.

The contact structure of a semiconductor IC according to the second aspect of the present invention has the effect of the first aspect. In addition to the effect of the first aspect, when the contact made of a coil spring is worn or damaged, Since it is only necessary to replace the fixed intermediate printed circuit board, maintenance costs can be reduced.

The contact structure of the semiconductor IC according to the third and fourth aspects of the present invention has a shorter signal path than the conventional one, and is therefore suitable for inspection of high-frequency characteristics. In addition, since the structure is simple, it can be manufactured at low cost, and when a metal ball or a metal bar as a contact is worn or damaged, it is only necessary to replace the insulating sheet to which the contact is fixed. Therefore, maintenance costs can be reduced. Furthermore, it is possible to sufficiently cope with a fine arrangement pitch of the solder balls.

[Brief description of the drawings]

FIG. 1 is an exploded sectional view showing a contact structure of a semiconductor IC according to a first embodiment of the present invention.

FIGS. 2A and 2B show a contact used in the first embodiment of the present invention, wherein FIG. 2A is a plan view and FIG. 2B is a front view.

FIG. 3 is an exploded cross-sectional view showing a contact structure of a semiconductor IC according to a second embodiment of the present invention.

FIG. 4 is an exploded sectional view showing a contact structure of a semiconductor IC according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing a modification of the third embodiment of the present invention.

FIG. 6 is a sectional view showing an example of a conventional contact structure.

FIG. 7 is a cross-sectional view showing an example of another conventional contact structure.

[Explanation of symbols]

1 semiconductor IC, 2 solder balls, 3 inspection circuit board,
4 land pattern, 5 contacts, 7 intermediary printed circuit board, 10 elastic sheet, 12 insulating sheet, 13 metal ball (contact), 14 metal rod (contact).

Claims (4)

[Claims] 1. A structure for electrically connecting a solder ball of a semiconductor IC having a solder ball as a connection electrode to a land pattern formed on an inspection circuit board,
On the land pattern of the inspection circuit board, there are provided contacts formed by forming coil springs in a ring shape individually corresponding to the solder balls, and the solder balls are pressed against these contacts. A contact structure for a semiconductor IC. 2. A structure for electrically connecting a solder ball of a semiconductor IC having a solder ball as a connection electrode to a land pattern formed on an inspection circuit board,
An intermediary printed circuit board is provided between the semiconductor IC and the inspection circuit board, and coil springs are formed in a ring shape on the upper and lower surfaces of the intermediary printed circuit board so as to individually correspond to the solder balls and the land patterns. A contact structure for a semiconductor IC, wherein a contact is provided, and the solder ball and the land pattern are pressed against the upper and lower contacts, respectively. 3. A structure for electrically connecting a solder ball of a semiconductor IC having solder balls as connection electrodes to a land pattern formed on an inspection circuit board,
An elastic sheet is interposed on the back side of the inspection circuit board and an insulating sheet is interposed between the front side and the semiconductor IC, and the insulating sheet has conductive parts at positions individually corresponding to the solder balls. Wherein the solder balls and the land patterns are pressed against the contacts, respectively. 4. The contact structure of a semiconductor IC according to claim 3, wherein said contact is made of a metal ball or a metal bar.