Heat sink for wafer test and wafer test equipment

Abstract

The utility model provides a heat sink for wafer testing and wafer testing equipment, and relates to the technical field of wafer testing. A first plate body of the heat sink comprises a body and a metal layer located on the body, the body is provided with a plurality of vacuum holes penetrating in the vertical direction, the vacuum holes are used for vacuumizing so as to adsorb a wafer located above the body, the back face of the wafer makes contact with the metal layer, and the diameter of each vacuum hole ranges from 3 micrometers to 5 micrometers. According to the technical scheme, the heat sink is equivalent to a micropore design, the wafer cannot be discolored due to the small aperture, it is ensured that the wafer test cannot affect the appearance of the wafer, and in addition, the wafer is in contact with the metal layer of the heat sink, so that the power-up test requirement of the wafer can be met.

Description

Technical Field

[0001] The utility model relates to the technical field of wafer testing, in particular to a heat sink and wafer testing equipment used for wafer testing. Background Art

[0002] In the prior art, wafers are typically placed in a sealed test chamber for testing, specifically on a heat sink within the chamber. After the wafer is placed on the heat sink, multiple vacuum holes are provided on the heat sink to hold the wafer in place and prevent it from moving during testing. However, when the wafer undergoes high-temperature testing, it can discolor, affecting its aesthetics. Therefore, there is an urgent need to design a heat sink that can hold the wafer in place without affecting its appearance or the power-on test. Utility Model Content

[0003] One purpose of the present invention is to provide a heat sink for wafer testing, so as to solve the technical problem in the prior art that wafers are prone to discoloration during high-temperature testing.

[0004] Another object of the present invention is to provide a wafer testing device having the above-mentioned heat sink.

[0005] In particular, the present invention provides a heat sink for wafer testing, comprising:

[0006] A first plate body, comprising a main body and a metal layer located on the main body, wherein the main body has a plurality of vacuum holes running vertically therethrough, wherein the vacuum holes are used for vacuuming to adsorb a wafer located above the main body, wherein the back side of the wafer contacts the metal layer, and the diameter of the vacuum holes is any value between 3 μm and 5 μm.

[0007] Optionally, the main body includes a first part and a second part, a plurality of vacuum holes are arranged on the first part, the second part is arranged around the periphery of the first part, the metal layer is provided on the top of the second part, the wafer covers the first part, and partially contacts the metal layer.

[0008] Optionally, the top of the second part is stepped and includes a first step and a second step, the first step is close to the first part, and the upper surface of the metal layer on the first step is flush with the upper surface of the first part, and the upper surface of the first step is higher than the upper surface of the second step.

[0009] Optionally, it also includes:

[0010] The second plate body has a concave cavity for placing the first plate body, and the second plate body has at least one air channel, and the air channel is communicated with the vacuum hole.

[0011] Optionally, the second plate has conductive properties and is connected to the heating platform, and the heat sink further includes:

[0012] The metal connecting piece contacts the metal layer of the first plate and is connected to the second plate.

[0013] Optionally, the metal connecting member is ring-shaped and is at least partially located above the metal layer of the heat sink.

[0014] Optionally, the metal connector and the second plate are connected via silver glue.

[0015] Optionally, the metal connector and the second plate are connected by screws.

[0016] Optionally, the first plate is made of ceramic material.

[0017] In particular, the present invention further provides a wafer testing device, comprising:

[0018] the aforementioned heat sink;

[0019] a heating platform, located below the heat sink, for heating the heat sink;

[0020] A test aging platform is connected to the heating platform to apply power to the back side of the wafer through the heating platform and the heat sink.

[0021] The first plate of the heat sink in this invention includes a main body and a metal layer located on the main body. The main body has multiple vacuum holes running vertically through it. The vacuum holes are used to create a vacuum to absorb the wafer located above the main body, with the back of the wafer in contact with the metal layer. The diameter of the vacuum holes is anywhere between 3μm and 5μm. This technical solution is equivalent to adopting a microporous design for the heat sink. Due to the small pore diameter, it does not cause discoloration of the wafer, ensuring that wafer testing does not affect the wafer's appearance. In addition, the contact between the wafer and the metal layer of the heat sink can meet the requirements of power-on testing of the wafer.

[0022] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0024] Figure 1This is a schematic structural diagram of a wafer placed on a heat sink according to an embodiment of the present invention;

[0025] Figure 2 is a schematic structural diagram of a heat sink according to an embodiment of the present utility model;

[0026] Figure 3 is a schematic partial cross-sectional view of a heat sink and a heating platform according to an embodiment of the present invention;

[0027] Figure 4 yes Figure 2 A schematic structural diagram of the first plate body in the heat sink shown;

[0028] Figure 5 yes Figure 2 Schematic structural diagram of the second plate body in the heat sink shown.

[0029] Reference numerals:

[0030] 100 - heat sink, 200 - wafer, 10 - first plate, 20 - second plate, 30 - metal connector, 121 - metal layer, 11 - first part, 12 - second part, 300 - heating platform, 21 - cavity, 22 - air channel, 122 - first step, 123 - second step. DETAILED DESCRIPTION

[0031] The following describes in detail embodiments of the present invention, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] In the description of the present invention, it should be understood that the terms "upper" and "lower" etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features, that is, include one or more of the features. In the description of the present utility model, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined. When a feature "includes or contains" one or more of the features it covers, unless otherwise specifically described, this indicates that other features are not excluded and may further include other features.

[0034] Unless otherwise specified or limited, the terms "connection" and "installation" should be interpreted broadly. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. A person of ordinary skill in the art should be able to understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0035] Unless otherwise defined, all terms (including technical terms and scientific terms) used in the description of this embodiment have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0036] Figure 1 1 is a schematic structural diagram of a wafer 200 placed on a heat sink 100 according to an embodiment of the present invention. Figure 2 is a schematic structural diagram of a heat sink 100 according to an embodiment of the present invention. Figure 3 FIG is a schematic partial cross-sectional view of a heat sink 100 and a heating platform 300 according to an embodiment of the present invention. Figures 1 to 3 As shown, in a specific embodiment, the heat sink 100 for testing the wafer 200 includes a first plate body 10, the first plate body 10 includes a main body and a metal layer 121 located on the main body, the main body has a plurality of vacuum holes running vertically through, the vacuum holes are used to evacuate to adsorb the wafer 200 located above the main body, the back of the wafer 200 is in contact with the metal layer 121, and the diameter of the vacuum hole is any value between 3μm and 5μm. For example, the diameter of the vacuum hole can be 3μm, 4μm or 5μm. Here, since the diameter of the vacuum hole is small, it is not shown in the accompanying drawings. Specifically, the metal layer 121 is in contact with the back of the wafer 200 and is used to power the back of the wafer 200 to perform a power-on test on the wafer 200.

[0037] Through research, the inventors of this utility model discovered that the discoloration of the backside of wafer 200 is caused by the large diameter of the vacuum holes in heat sink 100. The area of wafer 200 corresponding to the vacuum holes is suspended in the air, causing discoloration during high-temperature testing. Therefore, the inventors employed a micro-hole design in heat sink 100. Due to the small hole diameter, this prevents discoloration of wafer 200, ensuring that testing of wafer 200 does not affect its appearance. Furthermore, wafer 200 maintains contact with the metal layer 121 of heat sink 100, meeting the requirements of power-on testing of wafer 200.

[0038] In some embodiments, the vacuum holes are arranged in a honeycomb shape on the first plate 10 , so as to better absorb the wafer 200 and prevent the wafer 200 from moving during the test process.

[0039] In some embodiments, the body includes a first portion 11 and a second portion 12. A plurality of vacuum holes are provided on the first portion 11. The second portion 12 is disposed around the periphery of the first portion 11. A metal layer 121 is provided on the top of the second portion 12. The wafer 200 covers the first portion 11 and partially contacts the metal layer 121. Here, the first portion 11 and the second portion 12 are integrally formed.

[0040] See also Figure 2 and Figure 3 As shown, the first portion 11 is located in the middle of the first plate 10 and is annular. The second portion 12 is arranged around the outside of the first portion 11. The majority of the wafer 200 is located on top of the first portion 11, while the edge of the wafer 200 is located on top of the second portion 12, making contact with the metal layer 121 on top of the second portion 12. Here, the metal layer 121 is evaporated on top of the second portion 12. The metal layer 121 is also annular, equivalent to the metal layer 121 being located at the edge of the entire top of the first plate 10.

[0041] Figure 4 yes Figure 2 FIG. 1 is a schematic structural diagram of the first plate 10 in the heat sink 100. Figure 4 As shown, in some embodiments, the top of the second portion 12 is stepped and includes a first step 122 and a second step 123. The first step 122 is close to the first portion 11, and the upper surface of the metal layer 121 on the first step 122 is flush with the upper surface of the first portion 11, and the upper surface of the first step 122 is higher than the upper surface of the second step 123. Here, the tops of the first step 122 and the second step 123 are respectively provided with a metal layer 121, and the metal layers 121 at the two locations are connected. The back side of the wafer 200 is in contact with the metal layer 121 at the top of the first step 122. In other embodiments, the second portion 12 may not be designed to be stepped, and the top of the second portion 12 may be designed to be flush, which is specifically selected according to design requirements.

[0042] Figure 5 yes Figure 2 FIG. 1 is a schematic structural diagram of the second plate 20 in the heat sink 100. Figure 5 As shown, in some embodiments, the heat sink 100 further includes a second plate 20 having a cavity 21 for accommodating the first plate 10. The second plate 20 has at least one air channel 22 connected to the vacuum hole. The second plate 20 is equivalent to a metal disk, and the first plate 10 is embedded in the second plate 20. Negative pressure exists on the back of the first plate 10. This negative pressure is transmitted from the air channel 22 to the top surface of the first plate 10 through the vacuum hole, thereby adsorbing the wafer 200.

[0043] In some embodiments, there are multiple air channels 22, each of which is annular, and the multiple air channels 22 are arranged in concentric circles, and two adjacent air channels 22 are connected to each other. Here, the air channels 22 are connected to an external vacuum device.

[0044] In some embodiments, the second plate 20 has conductive properties and is connected to the heating platform 300. The heat sink 100 further includes a metal connector 30. The metal connector 30 contacts the metal layer 121 of the first plate 10 and is connected to the second plate 20. Here, the heating platform 300 is connected to the test aging platform, and the second plate 20 of the heat sink 100 is pressed above the heating platform 300. Figure 3 .

[0045] This embodiment connects the metal layer 121 to the heating platform 300 by designing the metal connector 30, and the heating platform 300 is connected to the test aging platform. Therefore, it is equivalent to connecting the metal layer 121 to the test aging platform, and the wafer 200 is in contact with the metal layer 121, thereby powering the back side of the wafer 200 to perform a power-on test on the wafer 200.

[0046] In some embodiments, the metal connector 30 is annular and at least partially located above the metal layer 121 of the first plate 10. Figure 3 Part of the metal connector 30 is located above the metal layer 121 of the first plate 10 , and the other part protrudes to the outside of the first plate 10 . Specifically, part of the metal connector 30 is located above the second step 123 .

[0047] In some embodiments, the metal connector 30 and the second plate 20 are connected by silver glue. The silver glue can extend directly from the bottom surface of the metal connector 30 to the second plate 20, or from the top surface of the metal connector 30 to the side surface of the metal connector 30, the bottom surface of the metal connector 30, and then to the second plate 20. The specific choice can be made based on design requirements.

[0048] In another embodiment, the metal connector 30 and the second plate 20 are connected by screws. Here, since the metal connector 30 is annular, multiple screws can be arranged along the circumference of the metal connector 30, and the multiple screws are respectively connected to the second plate 20. In other embodiments, the metal connector 30 and the second plate 20 can also be connected by other connection methods.

[0049] In some embodiments, the first plate 10 is made of ceramic material. This embodiment is equivalent to using microporous ceramic technology, which can not only absorb the wafer 200, but also does not cause the wafer 200 to turn white when the wafer 200 undergoes a high-temperature aging test. The entire edge of the microporous ceramic plate is gold-plated, that is, the metal layer 121, a very thin layer used to make the back of the wafer 200 conductive. It can be understood that the microporous ceramic plate itself is not conductive, so a metal layer 121 needs to be plated for conductivity. During the aging test, high voltage needs to be applied to the back of the wafer 200, and the back of the wafer 200 is in contact with the microporous ceramic plate, so it is necessary to add a metal layer 121 to achieve conductivity.

[0050] This embodiment also provides a wafer testing device, which includes the aforementioned heat sink 100, a heating platform 300, and a test and aging platform. The heating platform 300 is located below the heat sink 100 and is used to heat the heat sink 100. The test and aging platform is connected to the heating platform 300 to apply power to the back side of the wafer 200 through the heating platform 300 and the heat sink 100.

[0051] At this point, those skilled in the art should recognize that, although multiple exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications consistent with the principles of the present invention can be directly determined or deduced from the contents disclosed herein without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and deemed to cover all such other variations or modifications.

Claims

1. A heat sink for wafer testing, characterized in that: include: A first plate body, comprising a main body and a metal layer located on the main body, wherein the main body has a plurality of vacuum holes running vertically therethrough, wherein the vacuum holes are used for vacuuming to adsorb a wafer located above the main body, wherein the back side of the wafer contacts the metal layer, and the diameter of the vacuum holes is any value between 3 μm and 5 μm.

2. The heat sink according to claim 1, wherein: The main body includes a first part and a second part, multiple vacuum holes are arranged on the first part, the second part is arranged around the outer periphery of the first part, the metal layer is provided on the top of the second part, the wafer covers the first part, and partially contacts the metal layer.

3. The heat sink according to claim 2, characterized in that The top of the second part is stepped and includes a first step and a second step, the first step is close to the first part, and the upper surface of the metal layer on the first step is flush with the upper surface of the first part, and the upper surface of the first step is higher than the upper surface of the second step.

4. The heat sink according to claim 2, wherein: Also includes: The second plate body has a concave cavity for placing the first plate body, and the second plate body has at least one air channel, and the air channel is communicated with the vacuum hole.

5. The heat sink according to claim 4, characterized in that The second plate has conductive properties and is connected to the heating platform. The heat sink further includes: The metal connecting piece contacts the metal layer of the first plate and is connected to the second plate.

6. The heat sink according to claim 5, characterized in that The metal connecting piece is ring-shaped and is at least partially located above the metal layer of the first plate.

7. The heat sink according to claim 5, characterized in that The metal connecting piece and the second plate are connected by silver glue.

8. The heat sink according to claim 5, characterized in that The metal connecting piece and the second plate are connected by screws.

9. The heat sink according to claim 1, wherein: The first plate is made of ceramic material.

10. A wafer testing device, characterized in that: include: The heat sink according to any one of claims 1 to 9; a heating platform, located below the heat sink, for heating the heat sink; A test aging platform is connected to the heating platform to apply power to the back side of the wafer through the heating platform and the heat sink.

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