Flip chip single particle test heat dissipation system and heat dissipation method

Abstract

The invention discloses a flip chip single particle test heat dissipation system and heat dissipation method.The system comprises a radiator, a semiconductor chilling plate, a graphene film and an insulating spacer, the radiator is of a middle-hollowed-out structure, and a bare chip substrate can be completely exposed in the hollowed-out area of the radiator; the bottom of the radiator is attached to the hot end of the semiconductor chilling plate through heat-conducting glue. The semiconductor chilling plate adopts a middle hollow structural form, and a bare chip substrate can be completely exposed in a hollow area of the semiconductor chilling plate; the surface of the graphene film can completely cover the surface of the semiconductor chilling plate and is not hollowed out; one side of the graphene film is attached to the cold end of the semiconductor chilling plate through heat-conducting glue, and the other side of the graphene film directly covers the bare chip substrate and the insulating spacer of the flip chip. The method is implemented based on the system. The device has the advantages of simple and compact structure, convenience in operation, good heat dissipation effect, low cost and the like.

Description

Technical Field

[0001] The invention mainly relates to the field of integrated circuit chip single particle test, in particular to a flip chip single particle test heat dissipation system and a heat dissipation method. Background Art

[0002] In order to improve the heat dissipation capacity and interface performance of integrated circuit chips, high-end integrated circuit chips such as microprocessors are widely packaged using a flip chip structure, and heat sinks are installed on the chip surface for heat dissipation.

[0003] At present, flip chip heat dissipation structures such as Figure 1 As shown. The bare die 300 is composed of a substrate 100 and an interconnection layer 200. A metal ball 400 (bump) made of a material such as tin-lead or tin-silver connects the first surface 500 (pad) of the interconnection layer 200 of the bare die 300 (die) with the second surface 700 (pad) on the substrate 600, thereby connecting the bare die 300 to the substrate 600. The bottom surface of the substrate 600 is connected to the solder ball 800. At this time, the interconnection layer 200 of the bare die 300 is connected to the package substrate 600 downward, and the substrate 100 of the bare die 300 is facing upward. The heat sink 1 covers the substrate 100 of the bare die 300.

[0004] In the single particle test process, a heavy ion accelerator is generally used to generate high-energy heavy ions to irradiate silicon materials. Since the range of high-energy heavy ions generated by the heavy ion accelerator in silicon materials is tens to hundreds of microns, in order to ensure that the high-energy heavy ions can reach the flip chip during the single particle test, the heat sink 1 must be removed before the single particle test of the flip chip is performed using high-energy heavy ions to expose the substrate 100 of the bare chip 300. However, after removing the heat sink 1, the heat dissipation capacity of the flip chip drops sharply, and generally the working power exceeds 5 watts and cannot work normally.

[0005] In order to solve the above problems, the existing traditional method is to reduce the operating frequency of the flip chip, or shut down some of the internal modules of the flip chip and test each module separately, so that the operating power of the flip chip is reduced to less than 5 watts, and then conduct single-particle tests. However, after adopting this method, reducing the chip operating frequency will cause the test results to overestimate the flip chip's ability to resist single-particle transient effects, greatly increasing the error of the single-particle test; shutting down some of the internal modules of the flip chip and testing each module separately will increase the accelerator machine time used, and will also greatly increase the cost. At the same time, the coupling effect of each module makes the error of synthesizing the single-particle resistance of the whole chip through the module-level single-particle resistance test data extremely large. Summary of the invention

[0006] The technical problem to be solved by the present invention is: in view of the technical problems existing in the prior art, the present invention provides a flip chip single particle test heat dissipation system and heat dissipation method which has a simple and compact structure, is easy to operate, has a good heat dissipation effect and is low in cost.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions: A flip chip single particle test heat dissipation system comprises a heat sink, a semiconductor cooling sheet, a graphene film and an insulating gasket, wherein the heat sink adopts a structure with a hollow middle portion, and the hollowed-out region thereof can completely expose a bare chip substrate, and the bottom of the heat sink is bonded to the hot end of the semiconductor cooling sheet via a thermally conductive adhesive; the semiconductor cooling sheet adopts a structure with a hollow middle portion, and the hollowed-out region thereof can completely expose the bare chip substrate; the surface of the graphene film can completely cover the surface of the semiconductor cooling sheet without being hollowed out; one side of the graphene film is bonded to the cold end of the semiconductor cooling sheet via a thermally conductive adhesive, and the other side directly covers the bare chip substrate and the insulating gasket of the flip chip.

[0008] As a further improvement of the system of the present invention: the insulating gasket adopts a structure in which the middle is hollowed out, and the hollowed-out area can completely expose the bare chip substrate.

[0009] As a further improvement of the system of the present invention: the insulating gasket is placed on the substrate of the flip chip, and its hollowed-out area exposes the bare chip substrate of the flip chip; the insulating gasket contacts the other side of the graphene film.

[0010] As a further improvement of the system of the present invention: the bottom surface of the heat sink can completely cover the surface of the semiconductor cooling plate.

[0011] As a further improvement of the system of the present invention: the hot end of the semiconductor refrigeration sheet is adhered to the bottom of the radiator through thermal conductive adhesive, and the cold end of the semiconductor refrigeration sheet is adhered to the graphene film through thermal conductive adhesive.

[0012] As a further improvement of the system of the present invention: the power port of the semiconductor refrigeration chip is connected to the power supply through a wire; the power supply is used to power the semiconductor refrigeration chip so that the cooling power of the semiconductor refrigeration chip is not less than the working power of the flip chip.

[0013] As a further improvement of the system of the present invention: the graphene membrane is formed by pressing a multilayer graphene material at high temperature, has a thickness of 1 micron to 10 microns, and a thermal conductivity of not less than 1500 W / (m·K).

[0014] A heat dissipation method based on any one of the above flip chip single particle test heat dissipation systems, comprising: Step S1: Coat the hot end of the semiconductor cooling sheet with thermal conductive adhesive and attach it to the bottom surface of the radiator; Step S2: coating the cold end of the semiconductor refrigeration sheet with thermal conductive adhesive and attaching it to one side of the graphene film; Step S3: placing an insulating gasket on the substrate of the flip chip, with the hollowed-out area of ​​the insulating gasket exposing the bare chip substrate of the flip chip; Step S4: placing the assembly of the heat sink, the semiconductor cooling sheet and the graphene film on the assembly of the flip chip and the insulating spacer and fixing them well, so that the other side of the graphene film is in contact with the bare chip substrate surface of the flip chip and is also in contact with the insulating spacer; Step S5: Connect the power port of the semiconductor cooling chip to the power supply through a wire; Step S6: the power supply supplies power to the semiconductor cooling chip; Step S7: Start the flip chip process and start the single particle test.

[0015] As a further improvement of the method of the present invention: the combination of the flip chip and the insulating gasket is placed in the socket, and then the heat sink and the socket are fixed and locked, so that the combination of the heat sink, the semiconductor cooling sheet and the graphene film is tightly fitted to the surface of the bare chip substrate of the flip chip.

[0016] As a further improvement of the method of the present invention: the flip chip is soldered on the PCB board, and then the heat sink and the PCB board are fixed and locked, so that the combination of the heat sink, the semiconductor cooling plate and the graphene film is tightly fitted with the surface of the bare chip substrate of the flip chip.

[0017] Compared with the prior art, the advantages of the present invention are: 1. The flip chip single particle test heat dissipation system and heat dissipation method of the present invention realizes the single particle test of the flip chip under high power operation of more than 20W for the first time. The ultra-high thermal conductivity graphene film can effectively transfer the heat generated by the flip chip to the heat sink, which can ensure the normal operation of the flip chip with a power of more than 20W. At the same time, heavy ions can penetrate the ultra-thin graphene film, ensuring that the single particle test can be carried out normally.

[0018] 2. The flip chip single particle test heat dissipation system and heat dissipation method of the present invention have large heat dissipation power, can ensure that heavy ions reach the flip chip, and have a simple structure and easy operation. It enables the flip chip to carry out single particle testing under high power operation, and is particularly suitable for heat dissipation during high-power flip chip single particle testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the heat dissipation structure of the flip chip.

[0020] Figure 2 It is a schematic diagram of the overall structure of the flip chip single particle test heat dissipation system of the present invention.

[0021] Figure 3It is a top view schematic diagram of a radiator in a specific application example of the present invention.

[0022] Figure 4 It is a bottom view schematic diagram of a heat sink and a semiconductor refrigeration plate assembly in a specific application example of the present invention.

[0023] Figure 5 It is a top view schematic diagram of a graphene film and a semiconductor refrigeration sheet assembly in a specific application example of the present invention.

[0024] Figure 6 It is a top view schematic diagram of an insulating gasket and a flip chip assembly in a specific application example of the present invention.

[0025] Legend: 1. Radiator; 2. Semiconductor cooling sheet; 3. Graphene film; 4. Power supply; 5. Wire; 6. Thermal conductive adhesive; 7. Insulating gasket; 100. Substrate; 200. Interconnection layer; 300. Bare chip; 400. Metal ball; 500. First surface; 600. Base plate; 700. Second surface; 800. Solder ball. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are 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.

[0028] In addition, 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 indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0029] In the present invention, unless otherwise clearly specified and limited, the terms "assemble", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] like Figures 2 to 6 As shown, a flip chip single particle test heat dissipation system of the present invention comprises: a heat sink 1, a semiconductor cooling sheet 2, a graphene film 3 and an insulating gasket 7, wherein: The heat sink 1 adopts a structure in which the middle is hollowed out, and the hollowed-out area can completely expose the bare chip substrate 100 . The bottom of the heat sink 1 is attached to the hot end of the semiconductor cooling sheet 2 through a thermally conductive adhesive 6 .

[0031] The semiconductor cooling sheet 2 adopts a hollow structure in the middle, and its hollow area can completely expose the bare chip substrate 100, and the cooling power is not less than the working power of the flip chip; The surface of the graphene film 3 can completely cover the surface of the semiconductor cooling sheet 2 without any hollowing out; one side of the graphene film 3 is adhered to the cold end of the semiconductor cooling sheet 2 through the thermal conductive adhesive 6, and the other side is not coated with the thermal conductive adhesive 6 and directly covers the bare chip substrate 100 and the insulating gasket 7 of the flip chip.

[0032] The insulating spacer 7 is hollowed out in the middle, and the hollowed-out area can completely expose the bare chip substrate 100; the insulating spacer 7 is placed on the flip chip substrate 600, and the hollowed-out area exposes the bare chip substrate 100 of the flip chip. At the same time, the insulating spacer 7 also contacts the other side of the graphene film 3.

[0033] In a specific application example, the bottom surface of the heat sink 1 can completely cover the surface of the semiconductor cooling sheet 2 .

[0034] In a specific application example, the hot end of the semiconductor refrigeration sheet 2 is attached to the bottom of the heat sink 1 through the thermal conductive adhesive 6, and the cold end of the semiconductor refrigeration sheet 2 is attached to the graphene film 3 through the thermal conductive adhesive.

[0035] In a specific application example, the power port of the semiconductor refrigeration chip 2 is connected to the power supply 4 through a wire 5. The power supply 4 is used to supply power to the semiconductor refrigeration chip 2 so that the cooling power of the semiconductor refrigeration chip 2 is not less than the working power of the flip chip.

[0036] In a specific application example, the graphene film 3 is formed by pressing a multilayer graphene material at high temperature, with a thickness of 1 to 10 microns, preferably 3 to 5 microns; the thermal conductivity is not less than 1500 W / (m·K), preferably less than 1200 W / (m·K).

[0037] In a specific application example, the thickness of the insulating gasket 7 is 65um-90um, preferably 80um.

[0038] In a specific application example, the distance from the upper surface of the bare chip substrate 100 to the upper surface of the base plate 600 is 140 um-160 um, preferably 150 um.

[0039] In a specific application example, the thickness of the insulating spacer 7 is smaller than the distance from the upper surface of the bare chip substrate 100 to the upper surface of the base plate 600 .

[0040] In a specific application example, the material of the insulating gasket 7 can be insulating materials such as paper, plastic, silicone, rubber, etc., so as to insulate the graphene film 3 from the substrate.

[0041] The present invention further provides a heat dissipation method based on the above flip chip single particle test heat dissipation system, the steps of which include: Step S1: Coat the hot end of the semiconductor cooling sheet 2 with a thermally conductive adhesive 6 and attach it to the bottom surface of the heat sink 1; Step S2: coating the cold end of the semiconductor refrigeration sheet 2 with a thermally conductive adhesive 6 and attaching it to one side of the graphene film 3; Step S3: placing the insulating gasket 7 on the flip chip substrate 600, with the hollowed-out area of ​​the insulating gasket 7 exposing the bare chip substrate 100 of the flip chip; Step S4: Place the assembly of the heat sink 1, the semiconductor cooling sheet 2 and the graphene film 3 on the assembly of the flip chip and the insulating gasket 7 and fix them well, so that the other side of the graphene film 3 is in contact with the surface of the bare chip substrate 100 of the flip chip and is also in contact with the insulating gasket 7.

[0042] Step S5: Connect the power port of the semiconductor cooling sheet 2 to the power source 4 via the wire 5; Step S6: the power source 4 supplies power to the semiconductor cooling sheet 2; Step S7: Start the flip chip process and start the single particle test.

[0043] In a specific application example, according to actual needs, the present invention can use the following two methods to fix the two assemblies: Method 1: Place the combination of the flip chip and the insulating gasket 7 into the socket, and then fix and lock the heat sink and the socket so that the combination of the heat sink 1, the semiconductor cooling sheet 2 and the graphene film 3 fits tightly with the surface of the bare chip substrate 100 of the flip chip.

[0044] Method 2: Solder the flip chip to the PCB board, and then fix and lock the heat sink 1 and the PCB board so that the combination of the heat sink 1, the semiconductor cooling sheet 2 and the graphene film 3 is tightly fitted with the surface of the bare chip substrate 100 of the flip chip.

[0045] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A flip chip single particle test heat dissipation system, characterized in that: The invention comprises a heat sink (1), a semiconductor cooling sheet (2), a graphene film (3) and an insulating gasket (7); the heat sink (1) adopts a structure with a hollow middle portion, and the hollowed-out region thereof can completely expose a bare chip substrate (100); the bottom of the heat sink (1) is bonded to the hot end of the semiconductor cooling sheet (2) via a thermally conductive adhesive (6); the semiconductor cooling sheet (2) adopts a structure with a hollow middle portion, and the hollowed-out region thereof can completely expose the bare chip substrate (100); the surface of the graphene film (3) can completely cover the surface of the semiconductor cooling sheet (2) without being hollowed out; one side of the graphene film (3) is bonded to the cold end of the semiconductor cooling sheet (2) via a thermally conductive adhesive (6), and the other side directly covers the bare chip substrate (100) and the insulating gasket (7) of the flip chip.

2. The flip chip single particle test heat dissipation system according to claim 1, characterized in that: The insulating gasket (7) adopts a structure in which the middle is hollowed out, and the hollowed-out area can completely expose the bare chip substrate (100).

3. The flip chip single particle test heat dissipation system according to claim 2, characterized in that: The insulating gasket (7) is placed on the substrate (600) of the flip chip, and the hollowed-out area thereof exposes the bare chip substrate (100) of the flip chip; the insulating gasket (7) contacts the other side of the graphene film (3).

4. The flip chip single particle test heat dissipation system according to any one of claims 1 to 3, characterized in that: The bottom surface of the heat sink (1) can completely cover the surface of the semiconductor cooling sheet (2).

5. The flip chip single particle test heat dissipation system according to any one of claims 1 to 3, characterized in that: The hot end of the semiconductor cooling sheet (2) is attached to the bottom of the heat sink (1) via a thermally conductive adhesive (6), and the cold end of the semiconductor cooling sheet (2) is attached to the graphene film (3) via a thermally conductive adhesive (6).

6. The flip chip single particle test heat dissipation system according to any one of claims 1 to 3, characterized in that: The power port of the semiconductor cooling chip (2) is connected to a power source (4) via a wire (5); the power source (4) is used to supply power to the semiconductor cooling chip (2), so that the cooling power of the semiconductor cooling chip (2) is not less than the working power of the flip chip.

7. The flip chip single particle test heat dissipation system according to any one of claims 1 to 3, characterized in that: The graphene film (3) is formed by pressing a multilayer graphene material at high temperature, has a thickness of 1 micrometer to 10 micrometers, and a thermal conductivity of not less than 1500 W / (m·K).

8. A heat dissipation method based on the flip chip single particle test heat dissipation system according to any one of claims 1 to 7, characterized in that: include: Step S1: coating the hot end of the semiconductor cooling sheet (2) with a thermally conductive adhesive (6) and attaching the hot end to the bottom surface of the heat sink (1); Step S2: coating the cold end of the semiconductor cooling sheet (2) with a thermally conductive adhesive (6) and attaching the cold end to one side of the graphene film (3); Step S3: placing an insulating gasket (7) on the flip chip substrate (600), with the hollowed-out area of ​​the insulating gasket exposing the bare chip substrate (100) of the flip chip; Step S4: placing the assembly of the heat sink (1), the semiconductor cooling sheet (2) and the graphene film (3) on the assembly of the flip chip and the insulating gasket (7) and fixing them well, so that the other side of the graphene film (3) is in contact with the surface of the bare chip substrate (100) of the flip chip and is also in contact with the insulating gasket (7); Step S5: connecting the power port of the semiconductor cooling plate (2) to the power source (4) via the wire (5); Step S6: the power source (4) supplies power to the semiconductor cooling sheet (2); Step S7: Start the flip chip process and start the single particle test.

9. The heat dissipation method according to claim 8, characterized in that: The combination of the flip chip and the insulating gasket (7) is placed in the socket, and the heat sink (1) and the socket are fixed and locked, so that the combination of the heat sink (1), the semiconductor cooling sheet (2) and the graphene film (3) is tightly fitted to the surface of the bare chip substrate (100) of the flip chip.

10. The heat dissipation method according to claim 8, characterized in that: The flip chip is welded on the PCB board, and then the heat sink (1) and the PCB board are fixed and locked, so that the assembly of the heat sink (1), the semiconductor cooling sheet (2) and the graphene film (3) is tightly fitted with the surface of the bare chip substrate (100) of the flip chip.

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