Cover opening method of packaged chip

Abstract

The invention discloses an uncovering method of a packaged chip, which adopts a physical heating separation mode to carry out uncovering separation of the packaged chip, can avoid the risk that an internal cavity of the packaged chip is damaged by acid by adopting a chemical solution heating separation mode to a greater extent, and does not influence subsequent test analysis.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor detection, and in particular relates to a method for opening a packaged chip. Background Art

[0002] Uncapping of packaged chips, also known as component unsealing and uncapping, is a destructive testing method commonly used in chip failure analysis.

[0003] Since most of the current chips, especially MEMS chips, are connected by metal, the cover and the body are connected. The existing method of opening the cover and separating such chips often uses chemical solution heating. Due to the special metal connection process, it is difficult to separate the cover and the body with conventional chemical solutions, and it often takes a lot of time, such as heating time and chip cleaning, which increases the cost of consumables and labor costs. Moreover, the chemical solution heating method will affect the quality of the final inspection when selecting matching chemical solutions, heating temperature, heating reaction rate and other uncertain factors, making the final chip inspection quality unqualified.

[0004] Secondly, the use of chemical solution heating to open the packaged chip and separate it is easy to cause excessive corrosion of the packaged chip. The acid penetrates into the cavity of the packaged chip, causing damage to the internal structure.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The object of the present invention is to provide a method for opening a packaged chip, which can avoid the risk of the internal structure of the packaged chip cavity being damaged by the chemical solution caused by the traditional chemical solution heating separation.

[0007] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0008] A method for opening a packaged chip, comprising:

[0009] Providing a fixture, the fixture comprising a first carrier and a second carrier;

[0010] Curing the cover side and the body side of the packaged chip on the first carrier and the second carrier respectively by using a curing agent;

[0011] heating the cured overall structure at a first preset temperature for a first preset time to partially separate the adhesive between the cover and the body of the packaged chip;

[0012] Applying a preset separation force to the first carrier and the second carrier to separate the first carrier with one of the cover and the body of the packaged chip and the second carrier with the other of the cover and the body of the packaged chip;

[0013] The curing agent is removed to complete the separation of the first carrier, the cover, the main body and the second carrier.

[0014] In one or more embodiments of the present invention, the first preset temperature range is 450° C.-550° C., and the first preset time range is 8s-12s.

[0015] In one or more embodiments of the present invention, the preset separation force range is: 20N-30N; and / or,

[0016] A preset separation force is uniformly applied to the first carrier and the second carrier.

[0017] In one or more embodiments of the present invention, curing the cover side and the body side of the packaged chip on the first carrier and the second carrier respectively by a curing agent comprises:

[0018] Coating the curing agent on the surface of the first carrier, placing the packaged chip on the first carrier provided with the curing agent, so that the packaged chip is in full contact with the curing agent;

[0019] Coating the curing agent on the surface of the second carrier, and rotating the second carrier relative to the first carrier by a preset angle to cover the packaged chip;

[0020] Pressing the jig together and pressing to ensure that the first carrier, the second carrier, the packaged chip and the curing agent are in full contact;

[0021] The pressed whole structure is baked at a second preset temperature for a second preset time, so that the first carrier, the second carrier, the packaged chip and the curing agent are cured and bonded.

[0022] In one or more embodiments of the present invention, the preset angle range is 0°-180°; and / or,

[0023] The second preset temperature range is: 100° C.-150° C., and the second preset time range is: 1h-1.5h.

[0024] In one or more embodiments of the present invention, a groove adapted to the packaged chip is formed on the first carrier;

[0025] One of the cover side and the body side of the packaged chip is cured in the groove of the first carrier by the curing agent, and the other of the cover side or the body side of the packaged chip is cured on the second carrier by the curing agent.

[0026] In one or more embodiments of the present invention, the curing agent is formed at least on the bottom wall of the groove and a portion of the surface of the second carrier.

[0027] In one or more embodiments of the present invention, a hook fixed to the first carrier is disposed on the first carrier at a side away from the groove.

[0028] In one or more embodiments of the present invention, the hook is arranged corresponding to the groove.

[0029] In one or more embodiments of the present invention, applying a preset separation force to the first carrier and the second carrier to separate the first carrier having one of the cover and the body of the packaged chip and the second carrier having the other of the cover and the body of the packaged chip comprises:

[0030] The second carrier is fixed, and a separation force away from the second carrier is uniformly applied to the hook of the first carrier to separate the packaged chip cover and the body.

[0031] In one or more embodiments of the present invention, the materials of the first carrier and the second carrier include ceramics; and / or,

[0032] The surface smoothness of the first carrier and the second carrier is 80-90 GU; and / or,

[0033] The compressive strength of the first carrier and the second carrier is greater than or equal to 2500Mpa; and / or,

[0034] The fracture toughness compressive strength of the first carrier and the second carrier is greater than or equal to 11Mpa.m -3 / 2 and / or,

[0035] The elastic modulus of the first carrier and the second carrier is greater than or equal to 200 Gp; and / or,

[0036] The thermal expansion coefficient of the first carrier and the second carrier is greater than or equal to 10.5×10 -6 / ℃; and / or,

[0037] The thermal shock resistance of the first carrier and the second carrier is greater than or equal to 300Δ┱°C; and / or,

[0038] The resistance of the first carrier and the second carrier is greater than 10 12 Ω; and / or,

[0039] The temperature range that the first carrier and the second carrier can withstand is 500-1000°C.

[0040] In one or more embodiments of the present invention, the curing agent includes an epoxy adhesive.

[0041] In one or more embodiments of the present invention, an alcohol reagent is used to remove the curing agent.

[0042] Compared with the prior art, the method for opening the packaged chip of the present invention adopts a physical heating separation method, utilizing the insulation, high temperature resistance and high thermal conductivity of the carrier to achieve opening the cover, and can avoid the potential risk of using chemical solution heating to open the cover and separate, in which the chemical solution will penetrate into the cavity of the packaged chip while heating and corroding, thereby destroying the internal structure of the packaged chip.

[0043] The method for opening the packaged chip of the present invention adopts an unconventional chemical method - a physical heating separation method for opening and separating the packaged chip, which can avoid the risk of acid damage to the internal cavity of the packaged chip caused by chemical solution heating separation to a greater extent, and does not affect subsequent test analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 It is a flow chart of a method for opening a packaged chip in one embodiment of the present invention;

[0046] Figure 2a and Figure 2b This is a diagram showing the effect of performing cover opening and separation using the cover opening method for packaged chips according to an embodiment of the present invention;

[0047] Figure 3a and Figure 3b This is a diagram showing the effect of opening and separating the lid using the existing technology - chemical solution heating separation method. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0049] As mentioned in the background technology, the prior art often uses chemical solution heating to open the packaged chip, which can easily cause excessive corrosion of the packaged chip, and the acid solution drills into the cavity of the packaged chip, destroying its internal structure. Secondly, conventional chemical solution separation is difficult, time-consuming, and costly. Finally, the conventional chemical solution heating separation method has uncertain factors such as the selection of matching chemical solutions, heating temperature, and heating reaction rate that will affect the quality of the final packaged chip body inspection.

[0050] Based on this, the present invention proposes a method for opening the cover of a packaged chip, which adopts a physical heating separation method to open the cover and separate the packaged chip, which can avoid the risk of acid damage to the internal cavity of the packaged chip caused by the chemical solution heating separation method to a greater extent, and does not affect subsequent experimental analysis.

[0051] like Figure 1 As shown, a method for opening a packaged chip in an embodiment of the present invention specifically includes the following steps:

[0052] S1: Provide a jig, the jig comprising a first carrier and a second carrier.

[0053] The first carrier and the second carrier are both made of insulating, high temperature resistant and high thermal conductivity materials. Preferably, the first carrier and the second carrier are both ceramic sheets, which have the advantages of insulating, high temperature resistant and high thermal conductivity. The first carrier has a smooth first surface with a surface smoothness of 80-90GU. The second carrier has a smooth second surface with a surface smoothness of 80-90GU.

[0054] The compressive strength of the first carrier and the second carrier is greater than or equal to 2500Mpa, and the fracture toughness compressive strength is greater than or equal to 11Mpa.m -3 / 2 , elastic modulus greater than or equal to 200Gp, thermal expansion coefficient greater than or equal to 10.5x10 -6 / ℃, thermal shock resistance greater than or equal to 300Δ┱℃, electrical resistance greater than 10 12 The first carrier and the second carrier can withstand a temperature range of 500°C-1000°C.

[0055] S2: curing the cover side and the body side of the packaged chip on the first carrier and the second carrier respectively by using a curing agent.

[0056] Specifically, a proper amount of curing agent is squeezed out on the first surface of the first carrier, and the packaged chip is placed on the first surface provided with the curing agent with tweezers so that the packaged chip is in full contact with the curing agent. A proper amount of curing agent is squeezed out on the second surface of the second carrier, and the second carrier is horizontally rotated relative to the first carrier by a preset angle with its own center as the rotation point, and then covered on the packaged chip. Among them, the packaged chip is in full contact with the curing agent on the second surface of the second carrier. The pressing jig is pressed to make the first carrier, the second carrier, and the packaged chip in full contact with the curing agent. The pressed overall structure is baked at a second preset temperature for a second preset time to cure and bond the first carrier, the second carrier, the packaged chip, and the curing agent.

[0057] The curing agent is preferably a solvent-free high-strength epoxy adhesive suitable for bonding metal, wood, ceramic and glass, which can provide strong bonding strength. The curing agent can not only achieve the bonding between the ceramic sheet and the package chip, but also make the bonding strength non-dense, which is convenient for subsequent separation.

[0058] The preset angle range is 0°-90°, preferably 45°-90°. The second preset temperature range is 100°C-150°C, preferably 120°C. The second preset time range is 1h-1.5h, preferably 1.2h.

[0059] S3: heating the cured overall structure at a first preset temperature for a first preset time to partially separate the adhesive between the cover and the body of the packaged chip.

[0060] The first preset temperature range is 450° C.-550° C., preferably 500° C. The first preset time range is 8s-12s, preferably 10s. After heating at the first preset temperature for the first preset time, the adhesive between the cover and the body of the packaged chip will be slightly separated.

[0061] S4: applying a preset separation force to the first carrier and the second carrier to separate the first carrier having one of the cover and the body with the packaged chip and the second carrier having the other of the cover and the body with the packaged chip.

[0062] Specifically, the second carrier is fixed, and a preset separation force is uniformly applied to the first carrier away from the second carrier to separate the packaged chip cover and the body. The preset separation force range is: 20N-30N, preferably: 25N.

[0063] In this step, since the packaged chip body is relatively thin, too much separation force can easily damage the integrity of the internal device or body. Therefore, the separation force applied should not be too large and should be uniform to avoid mechanical damage to the packaged chip cavity and affect subsequent analysis.

[0064] S5: removing the curing agent, and completing the separation of the first carrier, the cover, the body and the second carrier.

[0065] Specifically, an alcohol reagent may be used to remove the curing agent.

[0066] For example, the first carrier and the second carrier that are separated and attached with the package chip cover or body are rinsed with alcohol, and the cover or body and the first carrier or the second carrier can be separated. Then a little alcohol is used to clean and wipe the used first carrier and second carrier jigs, so as to prepare for the next package chip opening and separation.

[0067] In a preferred embodiment, a groove adapted to the packaged chip can be formed on the first surface of the first carrier, and the depth of the groove is less than the thickness of the packaged chip, so that the packaged chip can still be bonded by the second carrier after being placed in the groove. One of the cover side and the body side of the packaged chip is cured in the groove of the first carrier by a curing agent, and the other of the cover side or the body side of the packaged chip is cured on the second surface of the second carrier by a curing agent. The curing agent can be formed at least on the bottom wall of the groove and on part of the second surface of the second carrier.

[0068] The provision of the groove can more conveniently and accurately limit and fix the packaged chip, and when the curing agent is formed on the side wall and bottom wall of the groove, the adhesion between the first carrier and the packaged chip can be improved, which is conducive to opening the packaged chip.

[0069] In order to make the separation force applied to the first carrier more uniform, a hook fixed to the first carrier is provided on the first carrier on the side away from the groove. The hook can be provided corresponding to the groove. When separating, the cover plate and the body can be separated by holding the second carrier plate with tweezers, hooking the hook of the first carrier plate with the hook, and gently pulling.

[0070] In the present invention, when the packaged chip is heated at a first preset temperature for a first preset time, the adhesive between the cover and the body of the packaged chip will be partially separated. Since the packaged chip is too small, directly using traditional mechanical force to separate it is easy to cause damage to the packaged chip or uneven force on the packaged chip, resulting in separation failure.

[0071] The advantage of using a jig separation method instead of a direct separation method is that the packaged chip and the cavity will not be damaged to varying degrees due to uneven force and improper touching during the separation process, and the packaged chip can be better separated.

[0072] Compared with the prior art, the method for opening the packaged chip of the present invention adopts a physical heating separation method, utilizing the insulation, high temperature resistance and high thermal conductivity of the carrier to achieve opening the cover, and can avoid the potential risk of using chemical solution heating for opening and separation, in which the chemical solution will penetrate into the cavity of the packaged chip while heating and corroding, thereby destroying the internal structure of the packaged chip.

[0073] The method for opening the packaged chip of the present invention adopts an unconventional chemical method - a physical heating separation method for opening and separating the packaged chip, which can avoid the risk of acid damage to the internal cavity of the packaged chip caused by chemical solution heating separation to a greater extent, and does not affect subsequent test analysis.

[0074] The method for opening the packaged chip of the present invention is described in detail below through a specific embodiment.

[0075] Select 2 1cm*1cm ceramic sheets. The compressive strength of each ceramic sheet is 2500Mpa, and the fracture toughness is 11Mpa.m -3 / 2 , elastic modulus: 200Gpa, thermal expansion coefficient: 10.5x10 -6 / ℃, thermal shock: 300Δ┱℃, electrical resistance greater than 10 12 Ω, operating temperature 500℃-1000℃.

[0076] A groove the size of the packaged chip to be opened is laser-blasted in the center of the back surface of one of the ceramic sheets to place the packaged chip to be opened. Two holes are laser-blasted on the front surface of the ceramic sheet with a laser machine. The two holes are set opposite to each other. A Min-shaped semicircular hook is selected and installed in the two holes of the ceramic sheet to fix it.

[0077] Squeeze a small amount of curing agent at the bottom of the groove. The curing agent is a high-quality, solvent-free, high-strength epoxy adhesive suitable for bonding metal, wood, ceramic and glass, which can provide strong bonding strength.

[0078] Use tweezers to place the packaged chip to be opened into the groove with the curing agent, so that the cover side or the body side of the packaged chip is in full contact with the curing agent.

[0079] A small amount of curing agent is also applied to another ceramic sheet, which is rotated 45 degrees horizontally relative to the first ceramic sheet with its center as the midpoint, and then covered on the other side of the packaged chip to be opened.

[0080] After manually pressing and gently pressing to make the ceramic sheet, the chip to be packaged and opened fully contact with the curing agent, put the whole structure into a tray and bake it in a 125 degree oven for 3 hours to solidify and bond the curing agent, the ceramic sheet and the chip to be packaged.

[0081] Heat the high temperature heating table to 500℃, put the cured whole structure in and heat for 10s. At this time, the cover and the body of the packaged chip to be opened have been slightly separated due to high temperature heating. Hold the ceramic sheet at the bottom with tweezers, and select a hook on the ceramic sheet at the top to hook the circular hook, and gently pull it upwards to separate.

[0082] The two ceramic sheets which are separated and respectively adhered with the package chip cover and the main body are flushed with alcohol, and the package chip cover, the main body and the ceramic sheet are separated.

[0083] Use a cotton swab dipped in a little alcohol to clean the used ceramic piece for next use.

[0084] Use plastic tweezers to gently pick up the packaged chip body and a corner of the cover after opening the cover, place them on a glass slide with the separated side facing up, and observe them under an optical microscope. The observation results are as follows: Figure 2a and 2b shown.

[0085] Figure 3a and Figure 3b This is a diagram showing the effect of opening and separating the lid using the common existing technology - chemical solution heating separation method.

[0086] refer to Figure 2a , Figure 2b and Figure 3a , Figure 3b As shown, the packaged chips separated by the packaged chip opening method of the present invention have no internal damage and a better separation effect.

[0087] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0088] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for opening a packaged chip, characterized in that: include: Providing a fixture, the fixture comprising a first carrier and a second carrier; Curing the cover side and the body side of the packaged chip on the first carrier and the second carrier respectively by using a curing agent; heating the cured overall structure at a first preset temperature for a first preset time to partially separate the adhesive between the cover and the body of the packaged chip; Applying a preset separation force to the first carrier and the second carrier to separate the first carrier with one of the cover and the body of the packaged chip and the second carrier with the other of the cover and the body of the packaged chip; The curing agent is removed to complete the separation of the first carrier, the cover, the main body and the second carrier.

2. The method for opening a packaged chip according to claim 1, characterized in that: The first preset temperature range is 450° C.-550° C., and the first preset time range is 8s-12s.

3. The method for opening a packaged chip according to claim 1, characterized in that: The preset separation force range is: 20N-30N; and / or, A preset separation force is uniformly applied to the first carrier and the second carrier.

4. The method for opening a packaged chip according to claim 1, characterized in that: The cover side and the body side of the packaged chip are respectively cured on the first carrier and the second carrier by a curing agent, comprising: Coating the curing agent on the surface of the first carrier, placing the packaged chip on the first carrier provided with the curing agent, so that the packaged chip is in full contact with the curing agent; Coating the curing agent on the surface of the second carrier, and rotating the second carrier relative to the first carrier by a preset angle to cover the packaged chip; Pressing the jig together and pressing to ensure that the first carrier, the second carrier, the packaged chip and the curing agent are in full contact; The pressed whole structure is baked at a second preset temperature for a second preset time, so that the first carrier, the second carrier, the packaged chip and the curing agent are cured and bonded.

5. The method for opening the packaged chip according to claim 4, characterized in that: The preset angle range is 0°-180°; and / or, The second preset temperature range is: 100° C.-150° C., and the second preset time range is: 1h-1.5h.

6. The method for opening a packaged chip according to claim 1, characterized in that: A groove adapted to the packaged chip is formed on the first carrier; One of the cover side and the body side of the packaged chip is cured in the groove of the first carrier by the curing agent, and the other of the cover side or the body side of the packaged chip is cured on the second carrier by the curing agent.

7. The method for opening a packaged chip according to claim 6, characterized in that: The curing agent is formed at least on the bottom wall of the groove and a portion of the surface of the second carrier.

8. The method for opening a packaged chip according to claim 6, characterized in that: A hook fixed to the first carrier is arranged on the first carrier at a side away from the groove.

9. The method for opening a packaged chip according to claim 8, characterized in that: Applying a preset separation force to the first carrier and the second carrier to separate the first carrier with one of the cover and the body of the packaged chip and the second carrier with the other of the cover and the body of the packaged chip, comprising: The second carrier is fixed, and a separation force away from the second carrier is uniformly applied to the hook of the first carrier to separate the packaged chip cover and the body.

10. The method for opening a packaged chip according to claim 1, characterized in that: The materials of the first carrier and the second carrier include ceramics; and / or, The surface smoothness of the first carrier and the second carrier is 80-90 GU; and / or, The compressive strength of the first carrier and the second carrier is greater than or equal to 2500Mpa; and / or, The fracture toughness compressive strength of the first carrier and the second carrier is greater than or equal to 11Mpa.m -3 / 2 and / or, The elastic modulus of the first carrier and the second carrier is greater than or equal to 200 Gp; and / or, The thermal expansion coefficient of the first carrier and the second carrier is greater than or equal to 10.5×10 -6 / ℃; and / or, The thermal shock resistance of the first carrier and the second carrier is greater than or equal to 300Δ┱°C; and / or, The resistance of the first carrier and the second carrier is greater than 10 12 Ω; and / or, The temperature range that the first carrier and the second carrier can withstand is 500-1000° C.; and / or, The curing agent includes an epoxy adhesive; and / or, The curing agent is removed using an alcohol reagent.

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