Probe and test head

Abstract

The utility model discloses a testing head, which comprises a probe, the probe comprises a main body and a filling piece, the main body extends lengthwise along the up-down direction and is provided with a first surface and a second surface which are oppositely arranged in a first direction perpendicular to the up-down direction, and a groove is arranged between the upper end and the lower end of the main body. The groove penetrates through the first surface and the second surface along a first direction; the filling piece is made of soft metal or soft metal alloy, the hardness of the filling piece is smaller than that of the main body, the stress of the probe is reduced, the conductivity of the filling piece is larger than that of the main body, the filling piece fills the groove, and the filling piece protrudes out of at least one of the first surface and the second surface in the first direction, so that the area and the volume of the probe are increased, and the bulk resistance is reduced; and the current bearing capability of the probe is improved.

Description

Technical Field

[0001] This utility model relates to a probe and a test head having the probe, and more particularly to a probe and test head that reduce probe stress and increase probe thickness to improve current carrying capacity. Background Technology

[0002] Test heads are typically used to perform electrical tests on circuits integrated on a chip before assembling them into a chip package. A test head usually includes at least two guide plates separated by partitions and multiple contact probes passing through the guide plates. The guide plates have multiple through-holes corresponding to the contact probes. The contact probes bend within the gap between the two guide plates and slide axially within the through-holes during pressing contact. The upper end of the contact probe contacts the contact pad of the space transducer, and the lower end contacts the contact pad of the chip under test. The test head performs the testing function of testing the chip circuitry by contacting the chip under test through the contact tip at the lower end of the contact probe. Long-term use of the test head to test chips will cause a certain degree of wear on the contact probes. Therefore, a portion of the length of the contact probe tip needs to be ground off for continued use. Over time, the overall length of the probe will become shorter, and its stiffness will gradually increase. This means that the force exerted by the corresponding contact tip on the contact pad of the chip under test will increase, which may cause the contact pad to crack, resulting in damage to the chip under test. The contact probe itself is also at risk of damage.

[0003] Traditional contact probes increase probe toughness by drilling a hole in the middle of the probe body and filling the hole with a tough insulating material. This also allows for adjustment of the force applied to the contact pad by the probe tip when the probe contacts the component under test. However, because the hole in these probes results in the loss of part of the main body material and the filling material is an insulating material (non-conductive material), the current capacity of the probe is reduced and its resistance value is increased accordingly. This is not conducive to applications such as carrying high-frequency signals at high frequencies, and increases the limitations of the probe's application scenarios.

[0004] Therefore, it is necessary to design a new probe and a test head with the probe to overcome the above problems. Utility Model Content

[0005] To address the problems of the prior art, the present invention aims to provide a probe and a test head having the probe that, while meeting the probe stiffness requirements, reduces the contact force applied to the tested component and improves the current carrying capacity.

[0006] To achieve the above objectives, this utility model provides a probe, comprising: a body extending longitudinally along a vertical direction, the body having a first surface and a second surface disposed opposite to each other in a first direction perpendicular to the vertical direction, the body having at least one groove between its upper and lower ends, the groove penetrating the first surface and the second surface along the first direction; and a filler, which is a soft metal or a soft metal alloy, having a hardness less than that of the body, and having a conductivity greater than that of the body, the filler filling the groove, and the filler protruding in the first direction from at least one of the first surface and the second surface.

[0007] Furthermore, the filler protrudes from the first surface and the second surface in a first direction, respectively.

[0008] Furthermore, the filler includes multiple metal layers, each of which extends in a vertical direction, and the multiple metal layers are stacked in a first direction, with adjacent metal layers made of different materials.

[0009] Furthermore, the filler material is at least one of gold, silver, and copper.

[0010] Furthermore, the filler fills the groove.

[0011] Furthermore, the probe is provided with a metal plating layer, which is deposited on the outer surface of the main body and the filler is exposed on the surface of the main body.

[0012] This utility model also provides a test head for contacting a space converter and a chip. The test head includes a probe, which includes a body and a filler. The body extends longitudinally in a vertical direction and has a first surface and a second surface disposed opposite each other in a first direction perpendicular to the vertical direction. The body has at least one groove between its upper and lower ends, and the groove penetrates the first surface and the second surface in the first direction. The filler is a soft metal or a soft metal alloy with a hardness less than that of the body and a conductivity greater than that of the body. The filler fills the groove and protrudes from at least one of the first surface and the second surface in the first direction. The body has a first contact portion and a second contact portion spaced apart in a vertical direction, and the groove is located between the first contact portion and the second contact portion. The first contact portion is used to contact the space converter, and the second contact portion is used to contact the chip.

[0013] Furthermore, both the first contact portion and the second contact portion are multi-contact structures.

[0014] Furthermore, a second direction is defined, perpendicular to the first direction and the up-down direction. The first contact portion includes at least two first contact points spaced apart along the second direction, and the second contact portion includes at least two second contact points spaced apart along the second direction.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] A filler made of a soft metal or a soft metal alloy, with a hardness less than that of the main body, is placed in the groove to reduce the force applied by the probe to the chip detection point. The filler has a higher conductivity than the main body, thereby improving the current carrying capacity of the probe. The filler protrudes from at least one of the first surface and the second surface in a first direction, increasing the area and volume of the probe and reducing the bulk resistance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram showing the test head of this utility model in contact with the chip and the space converter;

[0018] Figure 2 for Figure 1 A stereoscopic view showing only the probe and observing it from one perspective;

[0019] Figure 3 for Figure 2 A three-dimensional view of the probe from another perspective;

[0020] Figure 4 for Figure 2 A partial sectional view cut along the AA direction;

[0021] Figure 5 for Figure 2 A partial sectional view cut along the BB direction.

[0022]

[0023] Detailed Implementation

[0024] To facilitate a better understanding of the purpose, structure, and features of this utility model, the present utility model will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0025] For ease of understanding, this utility model defines a first direction (X-axis), a second direction (Y-axis), and a vertical direction (Z-axis), which are mutually perpendicular to each other.

[0026] It should be noted that the schematic diagram of the probe drawn in this utility model is not drawn according to the actual scale, but is drawn for illustration to highlight the important features to be shown in this utility model.

[0027] like Figure 1 As shown, a test head of this utility model includes a probe 1, an upper guide plate 2, and a lower guide plate 3. The upper guide plate 2 and the lower guide plate 3 are arranged vertically at intervals. The upper end of the probe 1 extends out of the upper guide plate 2 to contact a space converter 200, and the lower end of the probe 1 extends out of the lower guide plate 3 to abut against a chip 300.

[0028] like Figures 1 to 3 The diagram shows a specific embodiment of the probe in the test head of this utility model. The probe 1 includes a body 11 and a filler 12. The body 11 has a hardness of 325 HV (Vickers hardness) and can be made of highly conductive alloy materials such as copper-silver alloy, beryllium copper alloy, and titanium-copper alloy. The body 11 extends longitudinally in the vertical direction and has a first contact portion 111 and a second contact portion 112. The first contact portion 111 and the second contact portion 112 are spaced apart in the vertical direction. The first contact portion 111 is located at the upper end of the probe 1 to contact the space converter 200, and the second contact portion 112 is located at the lower end of the probe 1 to contact the chip 300.

[0029] like Figures 1 to 3 As shown, both the first contact portion 111 and the second contact portion 112 are multi-contact structures. The first contact portion 111 has two first contact points 1111, which are spaced apart along the second direction and contact the space converter 200 in the vertical direction. The second contact portion 112 has two second contact points 1121, which are spaced apart along the second direction and contact the chip 300 in the vertical direction. In other embodiments, the number of the first contact points 1111 and the second contact points 1121 may exceed two. The specific number of the first contact points 1111 and the second contact points 1121 is not limited here.

[0030] like Figure 1 , Figure 2 and Figure 3As shown, the main body 11 has a groove 113 between its upper and lower ends, that is, the groove 113 is located between the first contact portion 111 and the second contact portion 112, and the groove 113 is located between the upper guide plate 2 and the lower guide plate 3. The main body 11 also has a first surface 114 and a second surface 115 disposed opposite to each other in a first direction. The first surface 114 and the second surface 115 both extend longitudinally in the vertical direction. The groove 113 is a through groove that penetrates the main body 11 in the first direction. The groove 113 is located at approximately the middle of the main body 11 in the vertical direction, that is, the part of the main body 11 that is easily deformed by the force of the space converter 200 and the chip 300.

[0031] like Figure 4 and Figure 5 As shown, the filler 12 is conductive and its hardness is less than that of the main body 11. The filler 12 is a soft metal or soft metal alloy, such as copper, silver, gold and their alloys. In this embodiment, the material of the filler 12 is at least one of copper, silver and gold. Specifically, the material of the filler 12 includes copper, silver and gold. In other embodiments, the material of the filler 12 may be only one of copper, silver and gold or any two of them.

[0032] like Figure 2 and Figure 3 As shown, the filler 12 is closely attached to and filled in the groove 113 by electroplating, that is, the filler 12 is attached to the groove wall of the groove 113. The conductivity of the filler 12 is higher than that of the body 11. In this embodiment, the filler 12 fills the groove 113 and protrudes from the first surface 114 and the second surface 115 in the first direction. In other embodiments, the filler 12 may not fill the groove 113 but may still protrude from at least one of the first surface 114 and the second surface 115 in the first direction, or it may fill the groove 113 and protrude only from the first surface 114 or only from the second surface 115. The filler 12 may also be deposited in the groove 111 by chemical plating, sputtering, or physical vapor deposition (PVD) processes.

[0033] like Figure 4 and Figure 5As shown, the filler 12 includes multiple metal layers 121, each of which extends in a vertical direction. The multiple metal layers 121 are stacked in a first direction, and the materials of adjacent metal layers 121 are different. In this embodiment, the materials of each of the multiple metal layers 121 are different. The number of metal layers 121 is three, and the materials of the three metal layers 121 along the first direction are copper, silver, and gold, respectively. In other embodiments, the number of metal layers 121 may be more than three or equal to two, and is not necessarily three. The specific number of metal layers 121 is not limited here, and the materials of the metal layers 121 that are spaced apart from each other in the multiple metal layers 121 may be the same. For example, along the first direction, the materials of the metal layers 121 may be copper, silver, copper, or copper, silver, gold, copper, etc.

[0034] like Figure 4 and Figure 5 As shown, the probe 1 further includes a metal plating layer 13, which is deposited on the outer surface of the body 11 and the filler 12 is exposed on the surface of the body 11. In other embodiments, the metal plating layer 13 may be deposited on any surface of the body 11 and the filler 12 may be exposed on any surface of the body 11, depending on actual needs.

[0035] In summary, the probe and test head of this invention have the following beneficial effects:

[0036] 1. By using a filler 12 made of soft metal or soft metal alloy, and whose hardness is less than that of the main body 11, the rigidity of the probe 1 at the groove 111 is reduced after the filler 12 is plated on the groove 111. This effectively reduces the force exerted by the probe 1 on the contact pad of the chip 300 when the test head 100 contacts the chip 300. The filler 12 protrudes from at least one of the first surface 114 and the second surface 115 in the first direction, increasing the area and volume of the probe 1 and reducing the volume resistance. Furthermore, the conductivity of the filler 12 is greater than that of the main body 11, improving the current carrying capacity of the probe 1 and facilitating its application in carrying high-frequency signals.

[0037] 2. The filler 12 includes a plurality of metal layers 121, each of which extends in the vertical direction and the plurality of metal layers 121 are stacked in the first direction. The materials of adjacent metal layers 121 are different, so that metals of different materials can be alternately filled in the groove 113, increasing the diversity of the filler material. Thus, the conductivity and hardness of the filler 12 can be adjusted by different materials according to actual needs.

[0038] 3. The metal plating layer 13 is deposited on the outer surface of the main body 11 and the filler 12 is exposed on the surface of the main body 11, thereby adjusting the overall thickness of the probe 1, increasing the area and volume of the probe 1, and reducing the volume resistance.

[0039] 4. The first contact portion 111 and the second contact portion 112 are multi-contact structures, which increases the contact stability between the probe 1 and the space converter 200 and the chip 300.

[0040] The above detailed description is only a description of the preferred embodiment of this utility model and is not intended to limit the patent scope of this utility model. Therefore, all equivalent technical changes made using the content of this invention's specification and illustrations are included within the patent scope of this invention.

Claims

1. A probe, characterized in that, The probe comprises: a body extending longitudinally in a vertical direction, the body having a first surface and a second surface oppositely arranged in a first direction perpendicular to the vertical direction, the body being provided with at least one groove between two ends of the body in the vertical direction, the groove extending through the first surface and the second surface in the first direction; a filler made of soft metal or soft metal alloy, the filler having a hardness less than that of the body and an electrical conductivity greater than that of the body, the filler filling the groove, and the filler protruding at least one of the first surface and the second surface in the first direction.

2. The probe of claim 1, wherein: The filler protrudes the first surface and the second surface respectively in the first direction.

3. The probe of claim 1, wherein: The filler comprises a plurality of metal layers, each of the metal layers extending in the vertical direction, the plurality of metal layers being stacked in the first direction, and materials of adjacent two of the metal layers being different.

4. The probe of claim 3, wherein: Materials of each of the metal layers are different.

5. The probe of claim 1, wherein: The filler is made of at least one of gold, silver and copper.

6. The probe of claim 1, wherein: The filler fills the groove.

7. The probe of claim 1, wherein: The probe is provided with a metal plating layer, the metal plating layer being plated on an outer surface of the body and a surface of the filler exposed to the body.

8. A test head for abutting a space transformer and a chip, characterized by, The test head comprises the probe of any one of claims 1 to 7, the body having a first contact portion and a second contact portion spaced apart in the vertical direction, the groove being located between the first contact portion and the second contact portion, the first contact portion being used to abut against the space transformer, and the second contact portion being used to abut against the chip.

9. The test head of claim 8, wherein: The first contact portion and the second contact portion are both multi-contact structures.

10. The test head of claim 9, wherein: A second direction perpendicular to the first direction and the vertical direction is defined, the first contact portion comprises at least two first contact points spaced apart in the second direction, and the second contact portion comprises at least two second contact points spaced apart in the second direction.

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