JP7708614B2 - Strength evaluation jig - Google Patents

Description

The present invention relates to a strength evaluation tool that can be used to evaluate the flexural strength of semiconductor chips.

A number of planned division lines are set on the surface of the semiconductor wafer in a grid pattern, and devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integration) are formed in each of the areas defined by the planned division lines. Then, when the semiconductor wafer is divided along the planned division lines, individual semiconductor chips each having a device are formed.

When a semiconductor chip is subjected to a large impact, it may cause damage such as cracks or breaks, causing the device to lose its functionality. Therefore, in order to develop a semiconductor chip with a specified level of flexural strength, the flexural strength of prototype semiconductor chips is measured. One method for evaluating flexural strength is, for example, the 3-point bending method defined in SEMI (Semiconductor Equipment and Materials International) standard G86-0303.

For example, when measuring the flexural strength of a semiconductor chip using the three-point bending method, two cylindrical supports are inverted and arranged parallel to each other, and the semiconductor chip to be measured is placed on the side of the supports without being fixed to the supports. A cylindrical indenter is then placed above the semiconductor chip between the two supports and parallel to the two supports. The semiconductor chip is then pressed from above with the indenter until it breaks, and the load applied to the semiconductor chip at that time is measured as its strength (see Patent Document 1).

JP 2014-222714 A

To measure the flexural strength of semiconductor chips using the three-point bending method in the correct procedure and measure the flexural strength precisely, a large and expensive measuring device must be prepared. However, for example, if various types of semiconductor chips are prototyped one after another under various conditions at a semiconductor chip manufacturing site and it is desired to easily compare their flexural strengths, it is time-consuming and laborious to transport the manufactured semiconductor chips to the measuring device and perform precise measurements.

In particular, in recent years, there has been a remarkable trend toward miniaturization of electronic devices incorporating semiconductor chips, and miniaturization of semiconductor chips is also being demanded. Semiconductor chips measuring 1 cm square to 2 cm square or even smaller are also being manufactured. However, conventional flexural strength measuring devices using the three-point bending method are not always configured to measure the flexural strength of such small semiconductor chips, and it is not easy to measure the flexural strength of small semiconductor chips.

The present invention was made in consideration of these problems, and its purpose is to provide a strength evaluation tool that can easily evaluate the flexural strength of semiconductor chips.

According to one aspect of the present invention, a strength evaluation jig for a semiconductor chip includes a support body for supporting the semiconductor chip, a pressing body for pressing the semiconductor chip supported by the support body, and a plate-shaped depth adjustment body, the support body having a pair of support parts for supporting the semiconductor chips, a recess between the pair of support parts, and a pair of inclined parts inclined outwardly of each of the pair of support parts , the depth adjustment body having a pair of openings inserted into each of the pair of support parts of the support body, and outer ends of each of the pair of openings of the depth adjustment body are in contact with the pair of support parts of the support body. When each of the pair of support parts of the support body is inserted into each of the pair of openings until they overlap the respective inclined portions, the bridge part between the pair of openings of the depth adjustment body penetrates to a predetermined depth into the recess of the support body, and the upper end of the bridge part determines the depth of the recess, and a strength evaluation jig is provided that can evaluate the strength of the semiconductor chip based on the penetration depth of the semiconductor chip when the semiconductor chip supported by the pair of support parts is pressed by the pressing body and bent into the recess of the support body, and the presence or absence of cracks in the semiconductor chip that has penetrated into the recess.

A jig for evaluating the strength of a semiconductor chip according to one aspect of the present invention includes a support body that supports a semiconductor chip, and a pressing body that presses the semiconductor chip supported by the support body. When the semiconductor chip is supported on a pair of support parts of the support body and placed above a recess, and pressed from above by the pressing body, the semiconductor chip enters the recess while bending. The semiconductor chip does not crack until the degree of bending of the semiconductor chip exceeds the limit of its flexural strength, and when the degree of bending exceeds the limit of its flexural strength, the semiconductor chip cracks.

The degree of bending of the semiconductor chip is determined by the depth to which the semiconductor chip penetrates the recess in the support. Therefore, the strength of the semiconductor chip can be evaluated based on the depth to which the semiconductor chip penetrates the recess when it is pressed and bent by a pressing body, and the presence or absence of cracks in the semiconductor chip that has penetrated the recess.

For example, when comparing the flexural strength of two semiconductor chips, each semiconductor chip is pressed with a pressing body to bend it and penetrate it into a recess to a predetermined penetration depth. If a crack occurs in only one of the semiconductor chips, it is understood that the flexural strength of the semiconductor chip in which the crack occurs is relatively low. In this way, by using a semiconductor chip strength evaluation jig according to one aspect of the present invention, the flexural strength of the semiconductor chip can be easily evaluated.

Therefore, the present invention provides a strength evaluation tool that can easily evaluate the flexural strength of a semiconductor chip.

1 is a perspective view showing a semiconductor chip and a strength evaluation jig used to evaluate the flexural strength of the semiconductor chip; FIG. 2(A) is an oblique view showing a schematic first usage mode of the support body and the depth adjustment body, and FIG. 2(B) is an oblique view showing a schematic second usage mode of the support body and the depth adjustment body. FIG. 3(A) is a cross-sectional view showing a schematic first usage mode of the support body and the depth adjustment body, and FIG. 3(B) is a cross-sectional view showing a schematic second usage mode of the support body and the depth adjustment body. FIG. 4(A) is a perspective view showing a first mode of use of the strength evaluation jig, and FIG. 4(B) is a perspective view showing a second mode of use of the strength evaluation jig. FIG. 5(A) is an oblique view showing a schematic usage manner of a support body and a depth adjustment body of a strength evaluation jig relating to a first modified example, and FIG. 5(B) is a cross-sectional view showing a schematic usage manner of the strength evaluation jig relating to the first modified example. FIG. 6(A) is a perspective view showing a support body and a depth adjustment body of a strength evaluation jig according to a second modified example, and FIG. 6(B) is a side view showing a usage mode of the strength evaluation jig according to a third modified example. FIG. 7(A) is a side view showing a semiconductor chip and a first strength evaluation jig relating to the fourth modified example, and FIG. 7(B) is a side view showing a semiconductor chip and a second strength evaluation jig relating to the fourth modified example. FIG. 8(A) is a side view showing a schematic usage manner of a first strength evaluation jig according to the fourth modified example, and FIG. 8(B) is a side view showing a schematic usage manner of a second strength evaluation jig according to the fourth modified example.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings. First, a semiconductor chip whose flexural strength is evaluated using a strength evaluation jig according to this embodiment will be described. FIG. 1 includes a perspective view showing a schematic diagram of a semiconductor chip 1.

The semiconductor chip 1 is a chip cut from a disk-shaped semiconductor wafer made of a material such as Si (silicon), SiC (silicon carbide), GaN (gallium nitride), GaAs (gallium arsenide), or other semiconductor. The surface of the semiconductor wafer is partitioned by a number of streets (lines to be processed) that intersect with each other. Furthermore, devices such as ICs and LSIs are formed in each area partitioned by the streets on the surface of the wafer.

Then, when the semiconductor wafer is divided along the streets, individual semiconductor chips 1 each equipped with a device are formed. In recent years, there has been a remarkable trend toward miniaturization of electronic devices in which semiconductor chips 1 are mounted, and in response to this, semiconductor chips 1 measuring 1 cm to 2 cm square or smaller are being manufactured.

At the development site of semiconductor chip 1, semiconductor chip 1 is prototyped under various conditions, and the flexural strength of semiconductor chip 1 is measured as one of the evaluation items. Conventionally, the flexural strength of samples such as semiconductor chip 1 has been measured by the three-point bending method, but it is not easy to measure the flexural strength of small semiconductor chip 1, and it is time-consuming to transport the semiconductor chips 1 prototyped one after another to a measuring device and measure their flexural strength using the appropriate procedure. Furthermore, when it is desired to compare the relative magnitudes of the flexural strength of multiple semiconductor chips 1, precise measurements of the flexural strength are not necessary.

In this regard, it is advisable to use the strength evaluation jig according to this embodiment, which can easily evaluate the flexural strength of the semiconductor chip 1. Figure 1 includes a perspective view showing a schematic diagram of the strength evaluation jig 2 according to this embodiment. The configuration and method of use of the strength evaluation jig 2 will be described below.

The strength evaluation jig 2 according to this embodiment comprises three separate members: a support 12 that supports the semiconductor chip 1, a pressing body 4 that presses the semiconductor chip 1 supported by the support 12, and a depth adjustment body 24 that adjusts the depth of a recess 18 (described below) in the support 12. The support 12, pressing body 4, and depth adjustment body 24 are formed from materials such as stainless steel or resin, for example. However, the materials of each member are not limited to these. Next, the structure and function of each member will be described.

The pressing body 4 is a roughly triangular prism-shaped member, and is used with the top surface 6, which corresponds to one side of the triangular prism, in a horizontal plane. At this time, the two outer surfaces 8a, 8b, which correspond to the other sides of the triangular prism, are inclined in opposite directions at the same angle so as to be symmetrical with respect to a vertical plane that perpendicularly intersects with the top surface 6. The lower edge connecting the two outer surfaces 8a, 8b of the pressing body 4 is rounded to form a linear pressing portion 10. The pressing body 4 can be lowered with the pressing portion 10 in contact with the top surface of the semiconductor chip 1, thereby pressing the semiconductor chip 1.

The support 12 has a main body 14 with a pair of linear support parts 16a, 16b at the upper end, each of which supports a semiconductor chip 1, and a recess 18 is formed between the pair of support parts 16a, 16b of the main body 14. The bottom surface 22 of the main body 14 is flat. When the support 12 is placed on a horizontal table surface with the bottom surface 22 facing downward, the pair of support parts 16a, 16b sandwiching the recess 18 are at the same height and are parallel to each other.

The upper surface of the main body 14 is inclined downward from the pair of support parts 16a, 16b toward the outside. In other words, the support body 12 has a pair of inclined parts 20a, 20b that are inclined downward toward the outside of the pair of support parts 16a, 16b. The pair of inclined parts 20a, 20b are inclined in opposite directions at the same angle so that they are symmetrical to each other with respect to the vertical plane.

The plate-shaped depth adjustment body 24 has a pair of openings 26a, 26b arranged on either side of a bridge portion 28. The pair of openings 26a, 26b penetrates vertically, and the bridge portion 28 separates the pair of openings 26a, 26b. The width of the bridge portion 28, i.e., the distance between the pair of openings 26a, 26b, is set to be equal to or less than the width of the recess 18 of the support body 12.

The depth adjustment body 24 is used by being integrated with the support body 12 with the pair of support parts 16a, 16b of the support body 12 inserted into the pair of openings 26a, 26b. That is, the pair of support parts 16a, 16b are inserted into the pair of openings 26a, 26b until the outer ends of the pair of openings 26a, 26b overlap the pair of inclined parts 20a, 20b of the support body 12.

Here, the outer end hanging on the inclined portions 20a, 20b refers to a state in which the outer end abuts the inclined portions 20a, 20b and the depth adjustment body 24 is stably supported by the support body 12. In this state, the depth adjustment body 24 cannot proceed any further downward, and the height position of the depth adjustment body 24 is determined. In this state, the distance between the outer end of one opening 26a and the outer end of the other opening 26b is the same as the distance between the contact point of the one inclined portion 20a with the depth adjustment body 24 and the contact point of the other inclined portion 20b with the depth adjustment body 24.

At this time, the bridge portion 28 enters the recess 18 of the support 12 and partially fills the recess 18. Figures 2(A) and 2(B) are perspective views that show a schematic view of the depth adjustment body 24 integrated with the support 12. The bottom of the recess 18 of the support 12 integrated with the depth adjustment body 24 is defined by the upper end 30 of the bridge portion 28. In other words, the depth of the recess 18 changes due to the depth adjustment body 24.

The depth of the recess 18 defined by the upper end 30 of the bridge portion 28 varies with the height of the depth adjustment body 24 integrated with the support 12. In other words, the depth of the recess 18 can be adjusted to a predetermined depth by changing the height of the depth adjustment body 24 integrated with the support 12. The adjustment of the height of the depth adjustment body 24 can be achieved by the shape of the openings 26a, 26b.

Next, the geometric features of the pair of openings 26a, 26b that contribute to adjusting the height of the depth adjustment body 24 integrated with the support body 12 will be described. When viewed from a distance in the penetration direction of the openings 26a, 26b, the inner ends 32a, 32b of the pair of openings 26a, 26b are formed in parallel straight lines, and the outer ends opposite the inner ends 32a, 32b are formed in a stepped shape.

In the example shown in FIG. 1 etc., the outer ends of the openings 26a, 26b are divided into five regions. However, the number of divided regions that make up the outer ends of the openings 26a, 26b is not limited to five. The distances of each region from the inner ends 32a, 32b are different. Also, each region has a length equal to or greater than the thickness of the support 12. Furthermore, it is preferable that the shapes of the two openings 26a, 26b are linearly symmetrical to each other.

The region farthest from the inner ends 32a, 32b of the openings 26a, 26b is the first outer end 34a, 34b, and the region adjacent to the first outer end 34a, 34b via a step is the second outer end 36a, 36b. Similarly, the adjacent region is the third outer end 38a, 38b, and the further adjacent region is the fourth outer end 40a, 40b. The further adjacent region that is the closest to the inner ends 32a, 32b is the fifth outer end 42a, 42b.

When the openings 26a, 26b are configured in this manner, the height of the depth adjustment body 24 can be adjusted by determining which area of the outer ends of the openings 26a, 26b is placed over the inclined portions 20a, 20b of the support 12 when the depth adjustment body 24 and the support 12 are integrated. This is because the length between the contact point of one inclined portion 20a of the support 12 that contacts the depth adjustment body 24 and the contact point of the other inclined portion 20b that contacts the depth adjustment body 24 becomes longer the further downward.

For example, FIG. 2(A) is a perspective view showing a depth adjustment body 24 integrated with the support body 12 in a state where the third outer ends 38a, 38b of the openings 26a, 26b are placed on the inclined portions 20a, 20b of the support body 12. FIG. 2(B) is a perspective view showing a depth adjustment body 24 integrated with the support body 12 in a state where the first outer ends 34a, 34b of the openings 26a, 26b are placed on the inclined portions 20a, 20b of the support body 12.

When the depth adjustment body 24 is lowered and the third outer ends 38a, 38b of the openings 26a, 26b engage with the inclined portions 20a, 20b of the support body 12, the depth adjustment body 24 is supported by the support body 12 as shown in FIG. 2(A). FIG. 3(A) is a cross-sectional view showing the support body 12 and the depth adjustment body 24 at this time.

When the depth adjustment body 24 is moved laterally and further lowered so that the first outer ends 34a, 34b of the openings 26a, 26b engage with the inclined portions 20a, 20b of the support body 12, the depth adjustment body 24 is again supported by the support body 12 as shown in FIG. 2(B). FIG. 3(B) is a cross-sectional view showing the support body 12 and the depth adjustment body 24 at this time.

The distance between the third outer end 38a on one side and the third outer end 38b on the other side of the depth adjustment body 24 is shorter than the distance between the first outer end 34a on one side and the first outer end 34b on the other side. Therefore, the height of the depth adjustment body 24 when the third outer ends 38a, 38b are placed on the inclined portions 20a, 20b is higher than the height of the depth adjustment body 24 when the first outer ends 34a, 34b are placed on the inclined portions 20a, 20b.

That is, as shown in FIG. 3(A), the depth 44 of the recess 18 when the third outer ends 38a, 38b rest on the inclined portions 20a, 20b is smaller than the depth 46 of the recess 18 when the first outer ends 34a, 34b rest on the inclined portions 20a, 20b as shown in FIG. 3(B). In this way, the height of the upper end 30 of the bridge portion 28 in the recess 18 changes depending on the height of the depth adjustment body 24 when it is integrated with the support body 12, and since the height of this upper end 30 determines the depth of the recess 18, the depth of the recess 18 in the support body 12 can be adjusted by the depth adjustment body 24.

For example, if one wishes to evaluate the strength of a semiconductor chip 1 that is 20.0 mm square, the distance between the pair of support portions 16a, 16b, i.e., the width of the recess 18, should be between 5 mm and 10 mm. Also, the inclined portions 20a, 20b of the support 12 should be inclined at 45 degrees with respect to the bottom surface 22. Also, the depth of the recess 18 of the support 12 when not integrated with the depth adjustment body 24 should be 15 mm or less.

When the first outer ends 34a, 34b of the openings 26a, 26b of the depth adjustment body 24 are placed on the inclined portions 20a, 20b, the upper end 30 of the bridge portion 28 of the depth adjustment body 24 should be located 10 mm deeper than the upper end of the recess 18. Similarly, when the second outer ends 36a, 36b are placed on the inclined portions 20a, 20b, the depth of the recess 18 should be 8 mm, the third outer ends 38a, 38b should be 6 mm, the fourth outer ends 40a, 40b should be 8 mm, and the fifth outer ends 42a, 42b should be 2 mm. However, the adjustable depth of the recess 18 is not limited to this.

When evaluating the flexural strength of the semiconductor chip 1 using the strength evaluation jig 2, the depth adjustment body 24 is first integrated with the support body 12 at a predetermined height. Then, the semiconductor chip 1 is placed on the pair of supports 16a, 16b so as to span between them. Then, the pressing body 4 is moved above the recess 18, and the semiconductor chip 1 supported by the pair of supports 16a, 16b is pressed from above by the pressing body 4. Then, the semiconductor chip 1 pressed by the pressing body 4 is curved toward the recess 18.

Figures 4(A) and 4(B) are cross-sectional views that show a semiconductor chip 1 that has been pressed and curved by a pressing body 4. For example, the semiconductor chip 1 that has curved and entered the recess 18 is pressed by the pressing body 4 until it comes into contact with the bottom of the recess 18, i.e., the upper end 30 of the bridge portion 28 of the depth adjustment body 24.

During this process, it is detected whether or not a crack has occurred in the semiconductor chip 1. For example, the occurrence of a crack in the semiconductor chip 1 is detected by detecting the sound of destruction generated from the semiconductor chip 1. Alternatively, the occurrence of a crack may be detected by pressing the semiconductor chip 1 with the pressing body 4 until it contacts the upper end 30 of the depth adjustment body 24, releasing the pressure from the pressing body 4, and observing the semiconductor chip 1 with a microscope or the like. The method of detecting the crack and the timing at which the crack is detected are not particularly limited.

For example, when comparing the flexural strength of two semiconductor chips 1, the fifth outer ends 42a, 42b of the openings 26a, 26b of the depth adjustment body 24 are placed over the inclined portions 20a, 20b of the support body 12 to integrate the support body 12 and the depth adjustment body 24. One of the semiconductor chips 1 is then placed on the pair of supports 16a, 16b, and the pressing body 4 is used to press the semiconductor chip 1 so that it comes into contact with the upper end 30 of the bridge portion 28 of the depth adjustment body 24, and the presence or absence of cracks in the semiconductor chip 1 at this time is detected. Similarly, the other semiconductor chip 1 is pressed with the pressing body 4 to detect the presence or absence of cracks.

As a result, if a crack is detected in one semiconductor chip 1 but not in the other semiconductor chip 1, it is understood that the flexural strength of that one semiconductor chip 1 is relatively low. If a crack is not detected in either semiconductor chip 1, the height of the depth adjuster 24 is changed so that the depth of the recess 18 is increased, and a compression test is similarly performed on each semiconductor chip 1.

In the strength evaluation jig 2 according to this embodiment, the depth of the recess 18 can be adjusted by changing the manner in which the support 12 and the depth adjustment body 24 are integrated. Furthermore, by pressing each of the multiple semiconductor chips 1 with the pressing body 4, each semiconductor chip 1 can be bent to the same degree, so that the flexural strength of each semiconductor chip 1 can be easily compared based on whether or not cracks occur at this time. If it is only necessary to compare the flexural strength of each semiconductor chip 1, there is no need to precisely measure the flexural strength according to standards such as the three-point bending method, and the purpose can be fully achieved.

Next, a first modified example of the strength evaluation jig according to this embodiment will be described. FIG. 5(A) is a perspective view that shows a schematic usage mode of the support body 12 and depth adjustment body 24a of the strength evaluation jig according to the first modified example. FIG. 5(B) is a cross-sectional view that shows a schematic usage mode of the strength evaluation jig 2a according to the first modified example.

The support body 12 and the pressing body 4 of the strength evaluation jig 2a in the first modified example are unchanged, and only the depth adjustment body 24a is modified, and the only change to the depth adjustment body 24a is the configuration of the pair of openings 48a, 48b. Therefore, the above explanation can be referred to as appropriate for the other configurations.

In the depth adjustment body 24a of the strength evaluation jig 2a according to the first modified example, the inner walls of the pair of openings 48a, 48b are inclined walls 50a, 50b corresponding to the inclined portions 20a, 20b of the support body 12. In this case, as shown in FIG. 5(B), the pair of support parts 16a, 16b are passed through the pair of openings 48a, 48b, respectively, and the inclined portions 20a, 20b of the support body 12 are sandwiched between the inclined walls 50a, 50b, thereby integrating the support body 12 and the depth adjustment body 24a.

At this time, the inclined portions 20a, 20b of the support 12 and the inclined walls 50a, 50b of the depth adjustment body 24a are in surface contact with each other, so that the depth adjustment body 24a is supported by the support 12 more firmly and stably. When the depth adjustment body 24a is supported by the support 12 in surface contact, the depth adjustment body 24a can be positioned at a specified height with higher accuracy. In other words, the variation in the fixed height of the depth adjustment body 24a is reduced. Therefore, the evaluation and comparison of the flexural strength of the semiconductor chip 1 can be performed more precisely.

Next, a second modified example of the strength evaluation jig according to this embodiment will be described. Figure 6 (A) is a perspective view that shows a schematic diagram of the support body 12a and the depth adjustment body 24b of the strength evaluation jig according to the second modified example.

In the strength evaluation jig according to the second modified example, rail-shaped convex portions 56a, 56b are formed along the inclined portions 54a, 54b of the support body 12a, respectively. A concave portion 58a is formed in the lower part of the inner wall of the outer ends 62a, 62b of the pair of openings 60a, 60b of the depth adjustment body 24b, into which the convex portions 56a, 56b are fitted. There are no other changes, and the above description can be referred to as appropriate for other configurations.

When the depth adjustment body 24b is integrated with the support body 12a, the predetermined outer ends 62a, 62b are brought into contact with the inclined portions 54a, 54b of the support body 12a. At this time, the convex portions 56a, 56b provided on the inclined portions 54a, 54b are fitted into the concave portions 58a of the depth adjustment body 24b. If the depth adjustment body 24b can be integrated with the support body 12a at a plurality of different heights, the concave portions 58a are provided on the inner walls of the openings 60a, 60b in such a number and positions that they can be fitted into the convex portions 56a, 56b when the depth adjustment body 24b is integrated with the support body 12a at each height.

While the semiconductor chip 1 is being pressed from above by the pressing body 4, for some reason a force having a lateral component (horizontal direction, parallel to the bottom surface 22) may be unintentionally applied to the depth adjustment body 24b. However, if the convex portions 56a, 56b and the concave portion 58a are engaged, the depth adjustment body 24b will not shift relative to the support body 12a, causing the height of the depth adjustment body 24b to change.

Next, a third modified example of the strength evaluation jig according to this embodiment will be described. FIG. 6(B) is a cross-sectional view that shows a schematic diagram of the support 12b and the pressing body 4 of the strength evaluation jig 2b according to the third modified example, and the semiconductor chip 1 being pressed. The strength evaluation jig 2b according to the third modified example does not have a depth adjustment body.

Scales 64a, 64b are provided on both sides of the recess 18 on the side surface of the support 12b, aligned vertically at equal intervals. On both sides of the recess 18, the multiple lines constituting the scales 64a, 64b are set at the same height. There are no other changes to the strength evaluation jig 2b according to the third modified example. For other configurations, refer to the above explanation as appropriate.

When evaluating the flexural strength of the semiconductor chip 1 with the strength evaluation jig 2b, the worker places the semiconductor chip 1 on the pair of supports 16a, 16b of the support body 12b, and lowers the pressing body 4 to press and bend the semiconductor chip 1 into the recess 18. At this time, the semiconductor chip 1 is monitored, and any cracks that occur are immediately detected.

When a crack in the semiconductor chip 1 is detected, the descent of the pressing body 4 is stopped, and the height position of the lowest point of the semiconductor chip 1 in the recess 18 at this time is read by referring to the scales 64a and 64b. In the example shown in FIG. 6(B), it can be seen that the lowest end of the semiconductor chip 1 has reached the height of the fourth scale line from the top. The position of this lowest end is an index of the flexural strength of the semiconductor chip 1.

Each semiconductor chip 1 to be measured is supported in turn by supports 12a, 12b in the same manner, pressed from above by pressing body 4, and the position of the bottom end of semiconductor chip 1 when cracks occur is read by referring to scales 64a, 64b. By comparing the height positions of the bottom ends of each semiconductor chip 1 when cracks occur, the magnitude relationship of the flexural strength of each semiconductor chip 1 can be determined. In the strength evaluation jig 2b of the third modified example, a depth adjustment body is not required, and the flexural strength of semiconductor chip 1 can be evaluated quickly with a simpler configuration.

In the strength evaluation jig 2b according to the third modified example, the inclined portions 20a, 20b of the support 12b have no use, and the support 12b does not need to have the inclined portions 20a, 20b. However, if the support 12b has the inclined portions 20a, 20b, the depth adjustment body 24 can be integrated with the support 12b for use. In this case, the strength evaluation jig 2b can be used in a variety of ways according to the purpose.

Next, a fourth modified example of the strength evaluation jig according to this embodiment will be described. FIG. 7(A) is a side view showing a semiconductor chip 1 and a first strength evaluation jig 2c according to the fourth modified example, and FIG. 7(B) is a side view showing a semiconductor chip 1 and a second strength evaluation jig 2d according to the fourth modified example. FIG. 8(A) is a side view showing a schematic usage mode of the first strength evaluation jig 2c according to the fourth modified example, and FIG. 8(B) is a side view showing a schematic usage mode of the second strength evaluation jig 2d according to the fourth modified example.

The flexural strength of the semiconductor chip 1 is evaluated, for example, by a set of multiple strength evaluation jigs 2c, 2d with different configurations. However, a simple evaluation of the flexural strength of the semiconductor chip 1 is possible by using only one of the strength evaluation jigs 2c, 2d. The first strength evaluation jig 2c of the fourth modified example is composed of a support 12c and a pressing body 4c, and the second strength evaluation jig 2d of the fourth modified example is composed of a support 12d and a pressing body 4d. The following describes the first strength evaluation jig 2c as an example.

The support 12c of the first strength evaluation jig 2c has a pair of plate-shaped parts 70a, 70b each including a pair of support parts 68a, 68b. Here, in the first strength evaluation jig 2c, the pair of support parts 68a, 68b are planar rather than linear, and form the inner surfaces of the pair of plate-shaped parts 70a, 70b. In the support 12c, the pair of plate-shaped parts 70a, 70b are arranged in a V-shape by connecting one end of each of the pair of plate-shaped parts 70a, 70b to each other, and a recess 74a is formed by the inner surfaces of the pair of plate-shaped parts 70a, 70b.

The pressing body 4c also has a pair of outer surfaces 76a, 76b. The angle formed by the inner surfaces of the pair of plate-shaped portions 70a, 70b of the support body 12c coincides with the angle formed by the pair of outer surfaces 76a, 76b of the pressing body 4c.

When evaluating the flexural strength of the semiconductor chip 1 with the first strength evaluation jig 2c, first, as shown in FIG. 7(A), the semiconductor chip 1 is supported by a pair of support portions 66a, 66b of the support 12c. Then, the pressing portion 80a at the lower end of the pressing body 4c is brought into contact with the semiconductor chip 1 to bend the pressing body 4c, and the semiconductor chip 1 is inserted downward into the recess 74a. Finally, as shown in FIG. 8(A), the outer surfaces 76a, 76b of the pressing body 4c face the inner surface of the support 12c, and the semiconductor chip 1 is sandwiched between the support 12c and the pressing body 4c.

The degree of bending of the semiconductor chip 1 at this time is determined by the angle formed by the inner surfaces of the pair of plate-like portions 70a, 70b of the support 12c (the angle formed by the pair of outer surfaces 76a, 76b of the pressing body 4c). In other words, by using the first strength evaluation jig 2c, each semiconductor chip 1 to be evaluated for flexural strength can be bent to the same degree. Then, by determining whether cracks have occurred in the bent semiconductor chip 1, it can be determined whether each semiconductor chip 1 has a predetermined flexural strength.

Here, the degree of curvature of the semiconductor chip 1 when evaluating the flexural strength is determined by the angle formed by the inner surfaces of the pair of plate-shaped portions 70a, 70b of the support 12c. Therefore, by using another strength evaluation tool in which the inner surfaces form a different angle, the flexural strength of the semiconductor chip 1 can be evaluated in more detail.

The second strength evaluation jig 2d according to the fourth modified example shown in FIG. 7(B) includes a support 12d having a pair of plate-shaped portions 72a, 72b with support portions 68a, 68b on their inner surfaces, and a pressing body 4d having a pair of outer surfaces 78a, 78b. The support 12d has a recess 74b between the support portions 68a, 68b. The pressing body 4d contacts the semiconductor chip 1 with the pressing portion 80b at its lower end and presses the semiconductor chip 1 from above.

The second strength evaluation jig 2d differs from the first strength evaluation jig 2c in the angle formed by the inner surfaces of the pair of plate-shaped portions 72a, 72b. In this case, as shown in Figures 8(A) and 8(B), the degree of curvature of the semiconductor chip 1 when evaluating the flexural strength using the second strength evaluation jig 2d differs from the degree of curvature of the semiconductor chip 1 when evaluating the flexural strength using the first strength evaluation jig 2c.

For example, multiple semiconductor chips 1 to be evaluated for flexural strength are bent with the second strength evaluation jig 2d, and semiconductor chips 1 that did not crack are bent with the first strength evaluation jig 2c. The semiconductor chips 1 to be evaluated can then be classified into a group in which cracks occurred when the second strength evaluation jig 2d was used, a group in which cracks occurred when the first strength evaluation jig 2c was used, and a group in which no cracks occurred even when the first strength evaluation jig 2c was used. In other words, the semiconductor chips 1 can be classified by flexural strength.

In other words, by using multiple strength evaluation jigs according to the fourth modified example in which the inner faces of the pair of plate-shaped portions of the support body form different angles, the semiconductor chips 1 can be finely classified by their flexural strength according to the number of strength evaluation jigs. Furthermore, with the strength evaluation jig according to the fourth modified example, the semiconductor chips 1 can be bent to a predetermined degree without using a depth adjuster, so that the flexural strengths of multiple semiconductor chips 1 can be easily evaluated and compared.

However, when evaluating the flexural strength of the semiconductor chip 1, only one strength evaluation jig according to the fourth modified example may be used. For example, by using only a strength evaluation jig that bends the semiconductor chip 1 to a degree that corresponds to the flexural strength required for a specific application of the semiconductor chip 1, it is possible to easily evaluate whether each semiconductor chip 1 to be evaluated has a flexural strength sufficient for that application.

The present invention is not limited to the above embodiment, and can be modified in various ways. For example, in the above embodiment, as shown in FIG. 2(A) and other figures, a strength evaluation jig 2 including a depth adjustment body 24 in which the outer ends of the openings 26a, 26b are divided into multiple regions is described, but one aspect of the present invention is not limited to this.

In other words, the outer ends of each of the pair of openings 26a, 26b of the depth adjustment body 24 do not have to be divided into multiple regions. In this case, multiple depth adjustment bodies 24 with different distances between the outer ends of each of the pair of openings 26a, 26b are prepared, and the depth of the recess 18 of the support body 12 can be adjusted by using these depth adjustment bodies 24 appropriately.

For example, when a depth adjustment body 24 in which the distance between the outer ends of a pair of openings 26a, 26b is relatively short is integrated into the support body 12, the depth adjustment body 24 is positioned at a relatively high position, and the recess 18 is relatively shallow. When a depth adjustment body 24 in which the distance between the outer ends of a pair of openings 26a, 26b is relatively long is integrated into the support body 12, the depth adjustment body 24 is positioned at a relatively low position, and the recess 18 is relatively deep.

In other words, the strength evaluation jig 2 according to one aspect of the present invention may be composed of a plurality of depth adjustment bodies 24 in which the distance between the respective outer ends of a pair of openings 26a, 26b differs from each other, one support body 12, and one pressing body 4. Even in this case, the flexural strength of the semiconductor chip 1 can be evaluated while changing the depth of the recess 18 with the depth adjustment body 24.

In addition, the structures, methods, etc. according to the above embodiments can be modified as appropriate without departing from the scope of the present invention.

REFERENCE SIGNS LIST 1 semiconductor chip 2, 2a, 2b, 2c, 2d strength evaluation jig 4, 4c, 4d pressing body 6 upper surface 8a, 8b, 76a, 76b, 78a, 78b outer surface 10, 80a, 80b pressing portion 12, 12a, 12b, 12c, 12d support body 14 main body 16a, 16b, 66a, 66b, 68a, 68b support portion 18, 74a, 74b recess 20a, 20b, 54a, 54b inclined portion 22 bottom surface 24, 24a, 24b depth adjustment body 26a, 26b, 48a, 48b, 60a, 60b opening 28 bridge portion 30 upper end 32a, 32b, 52a, 52b inner end 34a, 34b, 36a, 36b, 38a, 38b, 40a, 40b, 42a, 42b, 62a, 62b Outer end 44, 46 Depth 50a, 50b Inclined wall 56a, 56b Convex portion 58a Concave portion 64a, 64b Scale 70a, 70b, 72a, 72b Plate-shaped portion

Claims (1)

A jig for evaluating the strength of a semiconductor chip,
A support for supporting the semiconductor chip;
a pressing body that presses the semiconductor chip supported by the support;
A plate-shaped depth adjustment body ,
The support is
a pair of support parts each supporting the semiconductor chip;
A recess between the pair of support portions;
a pair of inclined portions inclined toward the outside of the pair of support portions ,
the depth adjustment body has a pair of openings that are inserted into the pair of support portions of the support body,
when the pair of support portions of the support body are inserted into the pair of openings until the outer ends of the pair of openings of the depth adjustment body overlap the pair of inclined portions of the support body, a bridge portion between the pair of openings of the depth adjustment body enters the recess of the support body to a predetermined depth, and an upper end of the bridge portion defines the depth of the recess;
A strength evaluation jig capable of evaluating the strength of a semiconductor chip based on the penetration depth of the semiconductor chip when the semiconductor chip supported by a pair of support members is pressed and curved by the pressing body and enters the recess of the support member, and on the presence or absence of cracks in the semiconductor chip that has entered the recess.