Chip pin contact reliability detection method

Abstract

A chip pin contact reliability detection method, comprising the following steps: providing a chip to be tested; providing a transparent dummy chip, the dummy chip having the same shape, thickness and pin layout as the chip to be tested; spraying a reagent into a chip guide frame of a test seat to form liquid beads on the pin surface in the test seat chip guide frame; and placing the pins of the dummy chip in the chip guide frame after corresponding with the pins in the guide frame for detection. The method of the present application uses a transparent material to make a dummy chip having the same shape, thickness and pin layout as the chip to be tested, and cooperates with a volatile reagent sprayed in the test seat to atomize and infiltrate at the parts where the chip pins and the test seat pins are in good contact, thereby forming an obvious contact image, which facilitates direct observation of the contact condition of the pins.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit testing technology, and in particular to a method for detecting the reliability of chip pin contacts. Background Technology

[0002] Currently, conventional integrated circuit testing uses chip test sockets composed of spring pins, contacts, etc. When the pins of the chip under test (DUT) contact the probe pins of the chip socket, the contact condition is characterized by indentation on the test equipment, or a known good sample chip (GU) is used to compare with the DUT to determine the contact between the chip pins and the test socket pins. However, in actual chip testing, the contact condition of each pin is unknown, especially for high-frequency or even millimeter-wave frequency, high-power, and high-current chips. These methods cannot visually inspect the contact condition of critical pins, creating an urgent need for methods that can directly inspect pin contact. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a method for detecting the reliability of chip pin contacts. This method utilizes a chip made of transparent material combined with a volatile reagent to create an atomized sheet that wets the chip pins in contact with the test socket pins, forming a clear contact image that is easy to inspect directly.

[0004] To achieve the above objectives, the present invention provides a chip pin contact reliability detection method, comprising:

[0005] Provide the chip under test;

[0006] A transparent dummy chip is provided, the shape, thickness, and pin layout of which are the same as the chip under test;

[0007] Reagent is sprayed into the chip guide frame of the test socket, forming liquid beads on the surface of the pins inside the chip guide frame of the test socket;

[0008] After aligning the pins of the dummy chip with the pins in the guide frame, place it inside the chip guide frame for testing.

[0009] Furthermore, the reagent is a volatile reagent and can be retained in the test socket for at least 5 seconds to ensure that the detection can be performed.

[0010] Furthermore, the volatile solvent is alcohol.

[0011] Furthermore, the dummy chip is made of plexiglass.

[0012] Furthermore, the method for manufacturing the fake chip includes:

[0013] Provide transparent materials;

[0014] The transparent material is processed into a shape with the same size and thickness as the chip under test;

[0015] By laser etching out the outline of the chip pins, a dummy chip with the same shape, thickness, and pin layout as the chip under test is obtained.

[0016] Furthermore, the time during which the dummy chip is placed within the guide frame is sufficient to allow the atomization marks of the pins to be visible on the back of the dummy chip.

[0017] Furthermore, the pins are selected from spring pins, irregularly shaped pins, or conductive paper.

[0018] Furthermore, the chip under test is a high-frequency chip, a millimeter-wave chip, a high-power chip, or a high-current chip.

[0019] The chip pin contact reliability detection method provided by this invention has the following advantages compared with the prior art:

[0020] A dummy chip with the same shape, thickness, and pin layout as the chip under test is made of transparent material. A volatile reagent is sprayed into the test socket and atomized into a sheet to wet the areas where the chip pins and the test socket pins are in good contact, forming a clear contact image that allows for direct inspection of the pin contact.

[0021] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0023] Figure 1 This is a schematic diagram of indentation characterization according to an embodiment of the present invention;

[0024] Figure 2 This is a flowchart of a pin contact visualization detection method according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the test socket structure according to an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram comparing the chip under test and a dummy chip according to an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of a transparent dummy chip structure according to an embodiment of the present invention;

[0028] Figure 6This is a schematic diagram of the structure of the test socket pin according to an embodiment of the present invention. Detailed Implementation

[0029] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0030] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the invention. It should be understood that the accompanying drawings and embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the invention.

[0031] The term "comprising" and its variations as used herein are open-ended inclusions, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below.

[0032] It should be noted that the terms "one" and "multiple" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless explicitly stated otherwise in the context, they should be understood as "one or more". "Multiple" should be understood as two or more.

[0033] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] Regardless of the chip type, the process from design to mass production requires comprehensive performance testing and ATE (Automatic Test Equipment) screening to ensure performance is flawless before mass production can commence. ATE screening testing involves establishing a non-soldering electrical connection between the chip and the test board, followed by automated testing using laboratory instruments or dedicated ATE equipment. Currently, non-soldering testing typically uses contact-type chip sockets. A chip socket is an extension of the chip's pins. The main body of the socket is mounted on the PCB (evaluation board). After the chip is placed in the chip guide frame of the socket body, tightening the socket's test cover presses the chip downwards. This downward pressure pushes the probes that contact the chip's pins down onto the corresponding pads on the PCB, thus achieving an electrical connection between the chip and the PCB.

[0035] To ensure reliable test results, it is usually necessary to verify good contact between the chip pins and the test socket pins before chip testing. Therefore, it is necessary to test whether the chip pin contact is good.

[0036] Currently, the following two methods are commonly used to check whether the chip pins and the test socket pins are making good contact:

[0037] 1. The indentation characterization method was adopted, referring to... Figure 1 A layer of intact indentation paper is placed over the test socket pins. The chip under test (DUT) is then placed within the chip guide frame of the test socket, aligning its pins with the indentation paper. After the DUT is pressed down, indentations will be left on the paper between the chip pins and the test socket pins. The contact condition of the chip pins is determined by observing whether the indentations correspond to those of the chip pins and the test socket pins. For example, if the indentations of the corresponding chip pins and the test socket pins are misaligned or there is no indentation, it indicates unreliable chip pin contact.

[0038] 2. Use a GU (a known good sample chip) to compare with the chip under test to determine the contact between the chip pins and the socket probes.

[0039] However, neither of the above two methods can directly detect the contact of the chip pins, and there is an urgent need for a method to directly inspect the chip pin contact.

[0040] This invention provides a method for detecting the reliability of chip pin contacts, which forms a clear contact image at the pin contact area for easy direct inspection.

[0041] Figure 2 This is a flowchart of a chip pin contact reliability detection method according to an embodiment of the present invention. Figure 3 This is a schematic diagram of the test socket structure according to an embodiment of the present invention, in conjunction with reference to the reference. Figure 2 and Figure 3 The chip pin contact reliability detection method of the present invention includes the following steps:

[0042] Step 101: Provide the chip to be tested.

[0043] In this embodiment of the invention, the chip under test is a high-frequency chip, a millimeter-wave chip, a high-power chip, or a high-current chip. However, the types of chips under test that can be applied to this invention are not limited to the types listed above. The good contact of the chip pins listed here has a great impact on the test results. If other types of chips need to be tested for chip pin contact reliability, the method of this invention can also be applied.

[0044] Step 102: Provide a transparent dummy chip, the shape, thickness and pin layout of which are the same as the chip under test.

[0045] In this embodiment of the invention, the method for manufacturing a dummy chip is as follows:

[0046] Provide transparent materials;

[0047] The transparent material is processed into a shape with the same size and thickness as the chip under test;

[0048] By laser etching out the outline of the chip pins, a dummy chip with the same shape, thickness, and pin layout as the chip under test is obtained.

[0049] Preferably, the transparent material can be polymethyl methacrylate (PMMA), commonly known as plexiglass, which is beneficial for processing into the desired dummy chip. In other embodiments of the present invention, transparent materials such as polystyrene (PS) or polycarbonate (PC) can also be used, but the processing complexity may be higher.

[0050] Step 103: Spray reagent into the chip guide frame of the test socket to form liquid beads on the surface of the pins inside the chip guide frame of the test socket.

[0051] refer to Figure 3 The reagent is sprayed into the chip guide frame 11 of the test socket body 10. The guide frame 11 has pins corresponding to the pins of the chip under test. The sprayed reagent can form liquid beads on the surface of these pins.

[0052] In this embodiment of the invention, the sprayed reagent is a volatile reagent, such as alcohol. Other volatile, non-toxic solvents that do not corrode the test socket can also be used for spraying, so that it can remain in the test socket for at least 5 seconds to ensure that subsequent detection can be performed.

[0053] Step 104: After aligning the pins of the dummy chip with the pins in the guide frame, place it in the chip guide frame for testing.

[0054] In this embodiment of the invention, after the transparent dummy chip is placed on the test socket sprayed with volatile reagent, the tiny liquid beads on the surface of the test socket pins come into contact with the corresponding dummy chip pins to form a liquid wetting and diffusion shape. The areas with good contact form obvious contact images, which can directly detect the contact status of the dummy chip pins.

[0055] In this embodiment of the invention, the time during which the dummy chip is placed within the guide frame is sufficient to allow the atomization marks of the pins to be visible on the back of the dummy chip.

[0056] Figure 4 This is a schematic diagram comparing the chip under test and a dummy chip according to an embodiment of the present invention, as shown below. Figure 4As shown in Figures (a) and (b), the transparent dummy chip has the same shape, thickness and pin layout as the chip under test. Therefore, the contact condition of the pins of the chip under test can be reflected by the contact condition between the pins of the dummy chip and the pins of the test socket.

[0057] Figure 5 This is a schematic diagram of a transparent dummy chip structure according to an embodiment of the present invention, such as... Figure 5 As shown in Figure (a), the front side of the dummy chip is etched with the same pin outline as the chip under test. When these pins reliably contact the test socket pins sprayed with reagent, the displayed contact image can be observed on the back side of the transparent dummy chip, as shown in Figure (a). Figure 5 As shown in Figure (b), this method allows for a direct visual inspection of the reliability of chip pin contacts.

[0058] Because volatile solvents are used, the solvents evaporate after the test is completed, and the test stand can be restored to its original state without affecting its use.

[0059] The chip pin contact reliability testing method provided by this invention mainly utilizes the transparency of transparent materials. The transparent material is made into a dummy chip with the same appearance as the chip under test. It is then sprayed into the test socket with a volatile solvent. The solvent is atomized and wetted in the area where the chip pins and the test socket pins have good contact, forming a clear contact image, thereby enabling direct inspection of the pin contact.

[0060] refer to Figure 6 In the embodiments of the present invention, the pins can be selected from one of the following: spring pins (Pogo pins), irregular pins, or conductive paper.

[0061] like Figure 6 As shown in Figure (a), the Pogo pin is a spring-type probe formed by riveting and pre-pressing three basic components: needle shaft 12, spring 13, and needle tube 14 using precision instruments. It is the most common type of probe in a test socket.

[0062] like Figure 6 As shown in Figure (b), the irregularly shaped pin 15 is a probe made of a long strip of conductive material bent and fixed by an adhesive strip 16, with a certain sliding stroke. This type of probe increases the contact area between the PCB and the chip pad, allowing for higher frequencies. Depending on the bending shape, the position and number of adhesive strips, it is classified as S-pin, W-pin, and Z-pin. Compared to S-pin and W-pin, Z-pin is fixed by two adhesive strips, providing better positioning, less room for movement, higher frequencies, and a relatively higher price.

[0063] like Figure 6As shown in Figure (c), conductive paper is a material that is non-conductive in the horizontal direction but conductive in the vertical direction. It can replace the probe in the socket, is suitable for high frequency, and can be used up to 50-60G. It is more suitable for laboratory testing and not suitable for mass production testing. Its lifespan is shorter than that of the probe and it needs to be replaced after a period of use.

[0064] It will be understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting the reliability of chip pin contacts, characterized in that, include: Provide the chip under test; A transparent dummy chip is provided, the shape, thickness, and pin layout of which are the same as the chip under test; A volatile reagent is sprayed into the chip guide frame of the test socket, forming liquid beads on the surface of the pins inside the chip guide frame of the test socket; After aligning the pins of the dummy chip with the pins in the guide frame, place it inside the chip guide frame for testing; After the dummy chip is placed in the guide frame, liquid beads on the pin surface contact the corresponding pins of the dummy chip. Only in the area where the pins of the dummy chip make good contact with the pins, the liquid beads form a liquid wetting and diffusion shape, and produce a fogging mark on the pins that can be observed on the back of the transparent dummy chip. The reliability of the contact is determined by observing whether there is a fogging mark on the pins on the back of the transparent dummy chip. The volatile reagent can be retained in the test socket for at least 5 seconds to ensure that the detection can be performed; The time required for the dummy chip to be placed within the guide frame is sufficient to allow the atomization marks of the pins to be visible on the back of the dummy chip.

2. The chip pin contact reliability detection method according to claim 1, characterized in that, The volatile reagent is alcohol.

3. The chip pin contact reliability detection method according to claim 1, characterized in that, The fake chip is made of plexiglass.

4. The chip pin contact reliability detection method according to claim 1, characterized in that, The method for manufacturing the fake chip includes: Provide transparent materials; The transparent material is processed into a shape with the same size and thickness as the chip under test; By laser etching out the outline of the chip pins, a dummy chip with the same shape, thickness, and pin layout as the chip under test is obtained.

5. The chip pin contact reliability detection method according to claim 1, characterized in that, The pins are selected from spring pins, irregularly shaped pins, or conductive paper.

6. The chip pin contact reliability detection method according to claim 1, characterized in that, The chip under test is a high-frequency chip, a millimeter-wave chip, a high-power chip, or a high-current chip.

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