A chip separation method

Abstract

The present application discloses a chip separation method, which includes: obtaining a chip package; pre-treating the chip package to obtain a pre-treated chip package; based on a first preset heating temperature and a first preset reaction time, controlling the pre-treated chip package to react in fuming nitric acid to separate the chipset in the pre-treated chip package from a substrate; ultrasonically cleaning the separated chipset to obtain an ultrasonically cleaned chipset; based on a second preset heating temperature and a second preset reaction time, controlling the ultrasonically cleaned chipset to react in a mixed acid solution of a preset ratio to obtain a mixed acid-reacted chipset; based on a third preset heating temperature and a third preset reaction time, controlling the mixed acid-reacted chipset to react in ethylenediamine to completely separate each layer of chip wafers from the mixed acid-reacted chipset. The present application can non-destructively separate each layer of chip wafers from the inside of the package by dissection.

Description

Technical Field

[0001] The present application relates to the field of packaging reliability detection analysis, structural analysis, reverse analysis and failure analysis calculation of semiconductor devices and high-level packaged integrated circuits, and in particular to a chip separation method. Background Art

[0002] With the development of industries such as big data, artificial intelligence, and 5G communications, the demand for chip performance is getting higher and higher, and the chip manufacturing process is gradually approaching the limit of Moore's Law, making it difficult to improve the yield of chips. In order to meet the demand for chip performance and break the limitations of Moore's Law, the industry has proposed the concept of high-level packaging. Based on this, 2.5D / 3D packaging has been developed to increase the number of wafers in the package to achieve the purpose of improving chip performance. The complex packaging structure requires a high degree of maturity and matching in the packaging process and chip design. In this context, it is crucial to dissect and separate 2.5D / 3D packaged chips for detection and analysis.

[0003] At present, when analyzing high-end packaged chips, the grinding method is usually used, that is, the chipset is taken out and then ground layer by layer for inspection. However, this method of the prior art cannot separate and retain the complete chips, which will damage the chips and is not convenient for process quality and failure analysis of each layer of chips. Summary of the invention

[0004] In view of this, the present application provides a chip separation method, which is mainly capable of non-destructively separating each layer of chip wafer from the inside of the package, thereby facilitating process quality and failure analysis of each layer of chip.

[0005] According to a first aspect of the present application, a chip separation method is provided, the method comprising:

[0006] Obtaining a chip package to be separated;

[0007] Preprocessing the chip package to obtain a preprocessed chip package;

[0008] Based on a first preset heating temperature and a first preset reaction time, controlling the pretreated chip package to react in fuming nitric acid so that the chip group in the pretreated chip package is separated from the substrate;

[0009] Performing ultrasonic cleaning on the separated chipset to obtain an ultrasonically cleaned chipset;

[0010] Based on a second preset heating temperature and a second preset reaction time, controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio to obtain a chipset after mixed acid reaction, wherein the mixed acid solution is composed of fuming nitric acid and sulfuric acid;

[0011] Based on the third preset heating temperature and the third preset reaction time, the chipset after the mixed acid reaction is controlled to react in ethylenediamine, so as to completely separate each layer of chip wafers from the chipset after the mixed acid reaction.

[0012] Optionally, preprocessing the chip package to obtain a preprocessed chip package includes:

[0013] Performing a heat dissipation cover opening process or a laser thinning process on the chip package to obtain a chip package after preliminary processing;

[0014] The chip package after the preliminary treatment is subjected to substrate cutting treatment and substrate thinning treatment respectively to obtain the chip package after the pre-treatment.

[0015] Optionally, the chip package is subjected to a heat dissipation cover opening process or a laser thinning process to obtain a preliminarily processed chip package, including:

[0016] When the chip package is any one of a solder ball ball grid array package, a fan-out panel level package, and a silicon interposer chip stack package, based on a preset soaking time, the chip package is controlled to be soaked in an organic reagent to soften the heat dissipation cover adhesive of the chip package, and the heat dissipation cover is opened from the junction of the heat dissipation cover and the package substrate to obtain the chip package after the preliminary treatment;

[0017] When the chip package is a stacked package or a memory chip, laser thinning is performed on the chip package to obtain the preliminarily processed chip package.

[0018] Optionally, performing substrate cutting processing and substrate thinning processing on the chip package after the preliminary processing to obtain the pre-processed chip package includes:

[0019] Performing substrate cutting processing on the chip package after the preliminary processing to obtain a package reduced to the size of the chip;

[0020] Based on the hot melt wax, the chip surface of the package body reduced to the chip size is controlled to be attached to the ceramic substrate, and the grinder is controlled to grind and thin it at a preset speed to obtain the pre-treated chip package body.

[0021] Optionally, when the first preset heating temperature is 80 degrees and the first preset reaction time is 5 minutes, based on the first preset heating temperature and the first preset reaction time, controlling the pretreated chip package to react in fuming nitric acid so as to separate the chipset in the pretreated chip package from the substrate comprises:

[0022] The pre-treated chip package is controlled to be heated in fuming nitric acid at 80 degrees for 5 minutes, so that the chip group in the pre-treated chip package is separated from the substrate.

[0023] Optionally, the separating the chipset is ultrasonically cleaned to obtain the chipset after ultrasonic cleaning, comprising:

[0024] Ultrasonic cleaning of the separated chipset in acetone or anhydrous ethanol;

[0025] After performing ultrasonic cleaning on the separated chipset to obtain the chipset after ultrasonic cleaning, the method further comprises:

[0026] Removing the reaction residues of the chipset after ultrasonic cleaning, and drying with nitrogen to obtain a dried chipset;

[0027] The method of controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio based on the second preset heating temperature and the second preset reaction time to obtain the chipset after mixed acid reaction comprises:

[0028] Based on the second preset heating temperature and the second preset reaction time, the blow-dried chipset is controlled to react in a mixed acid solution of a preset ratio to obtain a chipset after mixed acid reaction.

[0029] Optionally, before controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio based on the second preset heating temperature and the second preset reaction time to obtain the chipset after mixed acid reaction, the method further includes:

[0030] Obtain a first volume of fuming nitric acid and a second volume of sulfuric acid;

[0031] The first volume of fuming nitric acid and the second volume of sulfuric acid are configured to form a mixed acid solution of the preset ratio.

[0032] Optionally, when the second preset heating temperature is 80 degrees and the second preset reaction time is 2 minutes, based on the second preset heating temperature and the second preset reaction time, controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio to obtain the chipset after mixed acid reaction, comprises:

[0033] The chipset after ultrasonic cleaning is controlled to be heated at 80 degrees for 2 minutes in a mixed acid solution of a preset ratio, and then ultrasonically cleaned after being taken out to obtain the chipset after the mixed acid reaction.

[0034] Optionally, when the third preset heating temperature is 100 degrees and the third preset reaction time is 5 minutes, based on the third preset heating temperature and the third preset reaction time, controlling the chipset after the mixed acid reaction to react in ethylenediamine to completely separate each layer of chip wafers from the chipset after the mixed acid reaction comprises:

[0035] Controlling the chipset after the mixed acid reaction to react in ethylenediamine at 100 degrees for 5 minutes, performing ultrasonic cleaning after taking out, and determining whether the chips of each layer are separated;

[0036] If not separated, the chipset after ultrasonic cleaning is continuously controlled to react in the mixed acid solution and the ethylenediamine in the preset ratio until the chips of each layer are separated.

[0037] Optionally, after controlling the chipset after the mixed acid reaction to react in ethylenediamine based on the third preset heating temperature and the third preset reaction time to completely separate each layer of chip wafers from the chipset after the mixed acid reaction, the method further includes:

[0038] The separated chips of each layer are respectively cleaned with pure water ultrasonic cleaning and acetone ultrasonic cleaning, and then dried with nitrogen to obtain dried chips of each layer;

[0039] Based on the fourth preset heating temperature, the dried chips are controlled to be heated on the heating device, and ethylenediamine is added to the surface of each layer of the chips. After the preset reaction time, the chips are ultrasonically cleaned with pure water and ultrasonically cleaned with acetone to obtain the cleaned chips; the cleaned chips are dried with nitrogen.

[0040] By means of the above technical scheme, a chip separation method provided by the present application is based on the following four structural features of 2.5D / 3D high-level packaging: 1. There are multiple layers of chips inside that are metal-interconnected through TSV and copper pillar; 2. Interlayer bonding is performed through epoxy resin molding compound (EMC); 3. The metal solder joints between the layers are dense and the distance between the upper and lower layers is extremely narrow; 4. The chip area of ​​each layer is large and the thickness is thin. The present application controls the chipset after ultrasonic cleaning to react in a mixed acid solution and ethylenediamine in a preset ratio in sequence, so that the above reagents can penetrate into the extremely narrow distance between the chip layers, and gradually corrode the epoxy resin molding compound and the metal interconnection structure, so that the chips can be separated layer by layer, that is, each layer of chip wafers can be non-destructively separated from the inside of the package, so as to facilitate the process quality and failure analysis of each layer of chips.

[0041] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0043] Figure 1 A schematic flow chart of a chip separation method provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0044] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0045] The existing grinding method cannot separate and retain complete chips, which will damage the chips and make it difficult to conduct process quality and failure analysis on each layer of chips.

[0046] In order to solve the above problems, an embodiment of the present invention provides a chip separation method, such as Figure 1 As shown, the method includes:

[0047] Step 101: Obtain a chip package to be separated.

[0048] Among them, the types of chip packages include Flip Chip Ball Grid Array (FCBGA), Fan-Out Panel Level Packaging (FOP), Chip-On-Wafer-On-Substrate (COWOS), Package on Package (POP), storage DDR chips and other stacked packaging types.

[0049] The chip package type to be separated in the embodiment of the present invention may be any of the above types.

[0050] Step 102: pre-process the chip package to obtain a pre-processed chip package.

[0051] For the embodiment of the present invention, before performing lossless chip separation on the package, the chip package needs to be pre-processed, and the pre-processing process mainly includes two processes, one is opening the heat dissipation cover or performing laser thinning, and the other is substrate cutting and substrate thinning. For the above pre-processing process, the method includes: performing heat dissipation cover opening or laser thinning on the chip package to obtain a chip package after preliminary processing; performing substrate cutting and substrate thinning on the chip package after preliminary processing to obtain the pre-processed chip package.

[0052] When the chip package is subjected to a heat dissipation cover opening process or a laser thinning process, if the packaging type of the chip package is any one of a solder ball type ball grid array package, a fan-out panel level package, and a silicon interposer chip stacking package, based on a preset immersion time, the chip package is controlled to be immersed in an organic reagent so that the heat dissipation cover adhesive of the chip package is softened, and the heat dissipation cover is opened from the junction of the heat dissipation cover and the packaging substrate to obtain the chip package after the preliminary treatment; if the packaging type of the chip package is a stacked package or a storage chip, the chip package is subjected to laser thinning to obtain the chip package after the preliminary treatment.

[0053] The organic reagent includes anhydrous ethanol, acetone, or other organic reagents, etc. The preset soaking time can be set according to actual business needs, and the embodiment of the present invention does not specifically limit this, such as setting the preset soaking time to 0.5 hours.

[0054] Specifically, if the chip package is of a packaging type of FCBGA, FOP, COWOS, etc., and the package is provided with a heat dissipation cover, and the internal adhesive is TIM adhesive, the chip package is placed in a sealed glass container, and an organic reagent such as anhydrous ethanol or acetone is poured into the container to soak the chip package in the organic reagent for 0.5 hours. After the chip package is taken out and the adhesive at the junction of the heat dissipation cover and the substrate around the chip package is observed to have softened, a blade is used to cut the adhesive around the junction of the heat dissipation cover and the packaging substrate to pry open the heat dissipation cover; if the chip package is of a packaging type of POP or a storage chip, the chip package is laser thinned to obtain a chip package after preliminary processing.

[0055] When the chip package after preliminary processing is subjected to substrate cutting processing and substrate thinning processing respectively, the chip package after preliminary processing is first subjected to substrate cutting processing to obtain a package reduced to the size of a chip, and then based on hot melt wax, the chip surface of the package reduced to the size of a chip is controlled to be attached to a ceramic substrate, and the grinder is controlled to grind and thin it at a preset speed to obtain the pre-processed chip package.

[0056] The preset speed may be set according to actual business requirements, and the embodiment of the present invention does not specifically limit this. For example, the preset speed is set to 200 r / min.

[0057] Specifically, a precision cutting machine is first used to cut the substrate of the chip package after preliminary processing, so as to cut off the substrate outside the chip range and reduce the package to the size of the chip, such as cutting off other parts outside the 2mm range of the chip welding area of ​​the package substrate. Then, hot melt wax is used to stick the chip surface on the ceramic substrate to prevent the chip from deforming and cracking during the thinning process. Then, the grinder is controlled to thin the substrate to the L1-L3 layer at a preset speed (such as 200r / min) with uniform force.

[0058] Step 103 : Based on a first preset heating temperature and a first preset reaction time, controlling the pretreated chip package to react in fuming nitric acid, so that the chip group in the pretreated chip package is separated from the substrate.

[0059] Among them, the first preset heating temperature can be set according to actual business needs, and the first preset reaction time can be set according to the size of the chip package, such as setting the first preset heating temperature to 80 degrees and the first preset reaction time to 5 minutes, or setting the first preset heating temperature to 100 degrees and the first preset reaction time to 10 minutes.

[0060] According to the embodiment of the present invention, the pre-treated chip package is controlled to be heated in fuming nitric acid at 80 degrees for 5 minutes, so that the chip group in the pre-treated chip package is separated from the substrate.

[0061] Specifically, the thinned chip package is placed in fuming nitric acid and heated to 80 degrees for 5 minutes before being taken out. During the reaction, it is determined whether the stacked chip group is separated from the substrate.

[0062] It should be noted that the first preset reaction time can be adjusted according to the size of the chip package, and the adjustment range of the first preset reaction time is 5 minutes to 10 minutes.

[0063] Step 104 , performing ultrasonic cleaning on the separated chipset to obtain a chipset after ultrasonic cleaning.

[0064] According to the embodiment of the present invention, the separated chipset is ultrasonically cleaned in acetone or anhydrous ethanol, and then the reaction residues of the chipset after ultrasonic cleaning are removed, and the chipset is blown dry with nitrogen to obtain a blown-dried chipset.

[0065] For example, the separated chipset is placed in acetone or anhydrous ethanol for ultrasonic cleaning for 30 seconds to remove the reaction residues of the chipset, and then dried with nitrogen.

[0066] Step 105: Based on a second preset heating temperature and a second preset reaction time, the chipset after ultrasonic cleaning is controlled to react in a mixed acid solution of a preset ratio to obtain a chipset after mixed acid reaction, wherein the mixed acid solution is composed of fuming nitric acid and sulfuric acid.

[0067] Among them, the second preset heating temperature and the second preset reaction time can be set according to actual business needs, such as setting the second preset heating temperature to 80 degrees and the second preset reaction time to 2 minutes.

[0068] According to the embodiment of the present invention, reagents need to be prepared before performing a mixed acid reaction. For this process, the method includes: obtaining a first volume of fuming nitric acid and a second volume of sulfuric acid; and preparing the first volume of fuming nitric acid and the second volume of sulfuric acid into a mixed acid solution of the preset ratio.

[0069] Among them, the preset ratio of fuming nitric acid and sulfuric acid in the mixed acid solution is 10:1.

[0070] For example, take 100 ml of fuming nitric acid and 10 ml of sulfuric acid, prepare a 10:1 mixed acid solution, and seal it for later use.

[0071] In the embodiment of the present invention, during the acid reaction, the chipset after ultrasonic cleaning is heated at 80 degrees for 2 minutes in a mixed acid solution of a preset ratio, and then ultrasonically cleaned after being taken out to obtain the chipset after the mixed acid reaction.

[0072] For example, take 10 mL of the prepared mixed acid solution, put the chipset after ultrasonic cleaning into the mixed acid solution so that the mixed acid solution can just cover the chipset, then heat to 80 degrees, react for 2 minutes, take it out and put it in acetone for ultrasonic cleaning for 30 seconds.

[0073] Step 106 : Based on a third preset heating temperature and a third preset reaction time, controlling the chipset after the mixed acid reaction to react in ethylenediamine, so as to completely separate each layer of chip wafers from the chipset after the mixed acid reaction.

[0074] Among them, the third preset heating temperature and the second preset reaction time can be set according to actual business needs, such as setting the third preset heating temperature to 100 degrees and the second preset reaction time to 5 minutes.

[0075] According to the embodiment of the present invention, the chipset after the mixed acid reaction is controlled to react in ethylenediamine at 100 degrees for 5 minutes, and ultrasonic cleaning is performed after being taken out, and it is determined whether the chips of each layer are separated; if not separated, the chipset after ultrasonic cleaning is continuously controlled to react in the mixed acid solution and the ethylenediamine in the preset ratio until the chips of each layer are separated.

[0076] Specifically, the chip group after the mixed acid reaction is placed in ethylenediamine and heated to 100 degrees, reacted for 5 minutes, taken out and ultrasonically cleaned in pure water for 30 minutes, and it is determined whether the layers of chips are separated. If not, continue to repeat steps 106 and 105 until the layers of chips are separated.

[0077] Furthermore, the separated chips of each layer are respectively subjected to pure water ultrasonic cleaning and acetone ultrasonic cleaning, and are blown dry with nitrogen after cleaning to obtain the dried chips of each layer; based on the fourth preset heating temperature, the dried chips of each layer are controlled to be heated on the heating device, and ethylenediamine is added to the surface of each layer of the chips, and after the preset reaction time, the chips of each layer to which ethylenediamine is added are respectively subjected to pure water ultrasonic cleaning and acetone ultrasonic cleaning to obtain the cleaned chips of each layer; the cleaned chips of each layer are blown dry with nitrogen.

[0078] Among them, the fourth preset heating temperature and preset duration can be set according to actual business needs, such as setting the fourth preset heating temperature to 100 degrees and the preset duration to 1 minute.

[0079] Specifically, each layer of the separated chips is firstly ultrasonically cleaned for 1 minute using pure water, then ultrasonically cleaned for 30 seconds using acetone, and then dried with nitrogen, so that the chips are cleaned after separation. After that, each layer of the dried chips is placed on a heating device and heated to 100 degrees, and ethylenediamine is added to the surface of each layer of the chips. After reacting for about 1 minute, pure water is used for ultrasonic cleaning for 1 minute, and then acetone is used for ultrasonic cleaning for 1 minute, and then dried with nitrogen to remove organic residues and PI layer residues on the chip surface, so that each layer of the chips can be completely separated, and the quality of each chip can be checked under a microscope.

[0080] The embodiment of the present invention sets the temperature at 60 degrees to control the above reaction to proceed at a relatively low rate, thereby avoiding the stress imbalance between chip layers caused by too fast a reaction speed and the generation of mechanical stress cracks. In addition, after the chip is separated and cleaned and dried with nitrogen, the embodiment of the present invention can obtain a chip with complete layers inside the package, thereby facilitating the process quality and failure analysis of the chip.

[0081] A chip separation method provided by an embodiment of the present invention controls a chip group after ultrasonic cleaning to react in a mixed acid solution and ethylenediamine in a preset ratio in sequence, so that the above reagents can penetrate into the extremely narrow gap between chip layers, gradually corrode the epoxy resin molding material and the metal interconnection structure, so that the chip can be separated layer by layer, that is, each layer of chip wafer can be non-destructively separated from the inside of the package, so as to facilitate process quality and failure analysis of each layer of chip.

[0082] Those skilled in the art will appreciate that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present application. Those skilled in the art will appreciate that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the description of the implementation scenario, or can be changed accordingly and located in one or more devices different from the present implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0083] The above serial numbers of this application are only for description and do not represent the advantages and disadvantages of the implementation scenarios. The above disclosure is only a few specific implementation scenarios of this application, but this application is not limited to them, and any changes that can be thought of by technicians in this field should fall within the scope of protection of this application.

Claims

1. A chip separation method, characterized in that: include: Obtaining a chip package to be separated; Preprocessing the chip package to obtain a preprocessed chip package; Based on a first preset heating temperature and a first preset reaction time, controlling the pretreated chip package to react in fuming nitric acid so that the chip group in the pretreated chip package is separated from the substrate; Performing ultrasonic cleaning on the separated chipset to obtain an ultrasonically cleaned chipset; Based on a second preset heating temperature and a second preset reaction time, controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio to obtain a chipset after mixed acid reaction, wherein the mixed acid solution is composed of fuming nitric acid and sulfuric acid; Based on the third preset heating temperature and the third preset reaction time, the chipset after the mixed acid reaction is controlled to react in ethylenediamine, so as to completely separate each layer of chip wafers from the chipset after the mixed acid reaction.

2. The method according to claim 1, characterized in that The preprocessing of the chip package to obtain a preprocessed chip package includes: Performing a heat dissipation cover opening process or a laser thinning process on the chip package to obtain a chip package after preliminary processing; The chip package after the preliminary treatment is subjected to substrate cutting treatment and substrate thinning treatment respectively to obtain the chip package after the pre-treatment.

3. The method according to claim 2, characterized in that The step of performing a heat dissipation cover opening process or a laser thinning process on the chip package to obtain a chip package after preliminary processing includes: When the chip package is any one of a solder ball ball grid array package, a fan-out panel level package, and a silicon interposer chip stack package, based on a preset soaking time, the chip package is controlled to be soaked in an organic reagent to soften the heat dissipation cover adhesive of the chip package, and the heat dissipation cover is opened from the junction of the heat dissipation cover and the package substrate to obtain the chip package after the preliminary treatment; When the chip package is a stacked package or a memory chip, laser thinning is performed on the chip package to obtain the preliminarily processed chip package.

4. The method according to claim 2, characterized in that: The step of performing substrate cutting and substrate thinning on the preliminarily processed chip package to obtain the pre-processed chip package comprises: Performing substrate cutting processing on the chip package after the preliminary processing to obtain a package reduced to the size of the chip; Based on the hot melt wax, the chip surface of the package body reduced to the chip size is controlled to be attached to the ceramic substrate, and the grinder is controlled to grind and thin it at a preset speed to obtain the pre-treated chip package body.

5. The method according to claim 1, characterized in that: When the first preset heating temperature is 80 degrees and the first preset reaction time is 5 minutes, based on the first preset heating temperature and the first preset reaction time, controlling the pretreated chip package to react in fuming nitric acid so that the chipset in the pretreated chip package is separated from the substrate includes: The pre-treated chip package is controlled to be heated in fuming nitric acid at 80 degrees for 5 minutes, so that the chip group in the pre-treated chip package is separated from the substrate.

6. The method according to claim 1, characterized in that The step of ultrasonically cleaning the separated chipset to obtain the chipset after ultrasonic cleaning comprises: Ultrasonic cleaning of the separated chipset in acetone or anhydrous ethanol; After performing ultrasonic cleaning on the separated chipset to obtain the chipset after ultrasonic cleaning, the method further comprises: Removing the reaction residues of the chipset after ultrasonic cleaning, and drying with nitrogen to obtain a dried chipset; The method of controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio based on the second preset heating temperature and the second preset reaction time to obtain the chipset after mixed acid reaction comprises: Based on the second preset heating temperature and the second preset reaction time, the blow-dried chipset is controlled to react in a mixed acid solution of a preset ratio to obtain a chipset after mixed acid reaction.

7. The method according to claim 1, characterized in that Before controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio based on the second preset heating temperature and the second preset reaction time to obtain the chipset after mixed acid reaction, the method further includes: Obtain a first volume of fuming nitric acid and a second volume of sulfuric acid; The first volume of fuming nitric acid and the second volume of sulfuric acid are configured to form a mixed acid solution of the preset ratio.

8. The method according to claim 1, characterized in that: When the second preset heating temperature is 80 degrees and the second preset reaction time is 2 minutes, based on the second preset heating temperature and the second preset reaction time, controlling the chipset after ultrasonic cleaning to react in a mixed acid solution of a preset ratio to obtain a chipset after mixed acid reaction, comprises: The chipset after ultrasonic cleaning is controlled to be heated at 80 degrees for 2 minutes in a mixed acid solution of a preset ratio, and then ultrasonically cleaned after being taken out to obtain the chipset after the mixed acid reaction.

9. The method according to claim 1, characterized in that: When the third preset heating temperature is 100 degrees and the third preset reaction time is 5 minutes, based on the third preset heating temperature and the third preset reaction time, controlling the chipset after the mixed acid reaction to react in ethylenediamine to completely separate each layer of chip wafers from the chipset after the mixed acid reaction, includes: Controlling the chipset after the mixed acid reaction to react in ethylenediamine at 100 degrees for 5 minutes, performing ultrasonic cleaning after taking out, and determining whether the chips of each layer are separated; If not separated, the chipset after ultrasonic cleaning is continuously controlled to react in the mixed acid solution and the ethylenediamine in the preset ratio until the chips of each layer are separated.

10. The method according to claim 1, characterized in that After controlling the chipset after the mixed acid reaction to react in ethylenediamine based on the third preset heating temperature and the third preset reaction time to completely separate each layer of chip wafers from the chipset after the mixed acid reaction, the method further includes: The separated chips of each layer are respectively cleaned with pure water ultrasonic cleaning and acetone ultrasonic cleaning, and then dried with nitrogen to obtain dried chips of each layer; Based on the fourth preset heating temperature, the dried chips are controlled to be heated on the heating device, and ethylenediamine is added to the surface of each layer of the chips. After the reaction is performed for a preset time, the chips are ultrasonically cleaned with pure water and ultrasonically cleaned with acetone to obtain the cleaned chips; After cleaning, each layer of the chips is dried with nitrogen.

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