Package structure and method for enhancing thermal conduction of thermal interface material and vapor chamber interface

Abstract

The application discloses a packaging structure for enhancing the interface heat conduction between a carbon fiber thermal interface material and a heat plate and a preparation method thereof, and comprises the following steps: treating the surface of the carbon fiber thermal interface material by using plasma treatment, so that carboxyl groups are formed on the surface of the carbon fiber thermal interface material; immersing the surface of the heat plate in a mercaptoethylamine-methyl mixed solution, and then drying to obtain the heat plate with a polymer curing film attached thereto; the surface of the polymer curing film is attached with amino groups; attaching the surface of the carbon fiber thermal interface material to the surface of the heat plate, and then pressing and baking to obtain the packaging structure for enhancing the interface heat conduction between the carbon fiber thermal interface material and the heat plate. By adding the covalent bond at the interface between the heat plate and the carbon fiber thermal interface material, the fast heat transfer channel is established between the carbon fiber thermal interface material and the heat plate through the covalent bond at the interface, the bonding strength between the carbon fiber thermal pad and the heat plate is improved, and the interface heat conduction and the interface reliability are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microelectronic packaging, in particular to a packaging structure for enhancing the thermal conduction of carbon fiber thermal interface material and a heat plate interface and a preparation method thereof. BACKGROUND

[0002] At present, the interface between the thermal interface material and the heat plate in the semiconductor device is generally pressed on the surface of the heat plate by physical pressure, so that the thermal interface material is combined on the surface of the heat plate for heat transfer. However, since the thermal interface material and the heat plate are only combined by van der Waals force, the interface thermal resistance of the thermal interface material / heat plate interface is large, which is not conducive to the interface heat transfer, and further leads to the decline of the heat dissipation performance and the reliability. SUMMARY

[0003] In view of the above-mentioned deficiencies existing at present, the present application provides a packaging structure for enhancing the thermal conduction of carbon fiber thermal interface material and a heat plate interface and a preparation method thereof. By adding a covalent bond at the interface between the heat plate and the carbon fiber thermal interface material, a fast heat transfer channel is established between the carbon fiber thermal interface material and the heat plate through the covalent bond at the interface, and the bonding strength between the carbon fiber thermal interface material and the heat plate is improved, and the interface heat conduction and the interface reliability are improved.

[0004] In order to achieve the above-mentioned purpose, the present application provides a preparation method of a packaging structure for enhancing the thermal conduction of carbon fiber thermal interface material and a heat plate interface, comprising the following steps:

[0005] Step 1: treating the surface of the carbon fiber thermal interface material by using plasma to form carboxyl on the surface of the carbon fiber thermal interface material;

[0006] Step 2: immersing the surface of the heat plate in a mercaptoethylamine-methyl mixed solution, and then drying to obtain a heat plate with a high molecular cured film attached thereto; wherein the surface of the high molecular cured film is attached with amino groups;

[0007] Step 3: attaching the surface of the carbon fiber thermal interface material prepared in step 1 to the surface of the heat plate prepared in step 2, and then pressing and baking to obtain a packaging structure for enhancing the thermal conduction of carbon fiber thermal interface material and a heat plate interface.

[0008] According to an aspect of the present application, in step 1, the power of the plasma treatment is 100-500W, and the time is 1-15min; the gas of the plasma treatment is air or a mixed gas of oxygen and argon.

[0009] According to an aspect of the present application, the volume ratio of oxygen to argon is 5-15:95-85.

[0010] According to one aspect of the present application, in step 2, the concentration of mercaptoethylamine in the mercaptoethylamine-methyl mixed solution is 1-10 mM.

[0011] According to one aspect of the present application, in step 2, the temperature of the drying is 30-60℃, and the time of the drying is 10 min-2h.

[0012] According to one aspect of the present application, in step 3, the temperature of the baking is 100-200℃, and the time of the baking is 10 min-2h.

[0013] According to one aspect of the present application, in step 3, the pressure applied in the tabletting is 50-200 kPa.

[0014] Based on the same inventive concept, the present application also provides a packaging structure of the enhanced carbon fiber thermal interface material and the heat plate interface thermal conduction prepared by the above preparation method.

[0015] According to one aspect of the present application, the carbon fiber thermal interface material and the heat plate are connected through an amide bond.

[0016] The reaction principle of the present application is as follows:

[0017] The present application processes the carbon fiber thermal interface material through plasma, so that a certain amount of carboxyl groups are formed on the surface of the carbon fiber thermal interface material; mercaptoethylamine is adsorbed on the gold-plated heat plate and exists in the form of N-H; the carboxyl groups on the surface of the carbon fiber thermal interface material react with the N-H on the surface of the heat plate to generate an amide bond.

[0018] The present application has the following beneficial effects:

[0019] The present application adds a covalent bond at the interface between the heat plate and the carbon fiber thermal interface material, establishes a rapid heat transfer channel between the carbon fiber thermal interface material and the heat plate through the covalent bond at the interface, and improves the bonding strength between the carbon fiber thermal pad and the heat plate, and improves the interface thermal conduction and the interface reliability. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 (a) is the XPS graph of the surface of the carbon fiber thermal interface material described in Example 1 of the present application before plasma treatment; Figure 1 (b) is the XPS graph of the surface of the carbon fiber thermal interface material described in Example 1 of the present application after plasma treatment;

[0021] Figure 2 is the Fourier transform infrared spectrum of the surface of the polymer cured film on the heat plate of Example 1 of the present application;

[0022] Figure 3 is the infrared spectrum of the surface of the carbon fiber thermal interface material in the packaging structure of Example 1 of the present application. DETAILED DESCRIPTION

[0023] In order to make the present application more easily understood, the present application is further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present application and not used to limit the scope of the present application. Obviously, the described examples are only a part of the examples of the present application and not all the examples. Based on the examples in the present application, all other examples obtained by those skilled in the art without making creative efforts are within the scope of protection of the present application. Unless otherwise defined, the professional terms used below are consistent with the meanings understood by those skilled in the art; unless otherwise specified, the raw materials and reagents involved in the present application can be purchased from the market or prepared by the known methods.

[0024] At present, the interface between the thermal interface material and the vapor chamber in the semiconductor device is generally pressed on the surface of the vapor chamber by physical pressure, so that the thermal interface material is combined on the surface of the vapor chamber for heat transfer. However, since the thermal interface material and the vapor chamber are only combined by van der Waals force, the interface thermal resistance of the thermal interface material / vapor chamber interface is large, which is not conducive to the interface heat transfer, and further leads to the decline of the heat dissipation performance and the decline of the reliability performance.

[0025] In order to solve the above problems, the present application provides a preparation method of a packaging structure for enhancing the thermal conduction of the interface between the carbon fiber thermal interface material and the vapor chamber, comprising the following steps:

[0026] Step 1: treating the surface of the carbon fiber thermal interface material by using plasma to form carboxyl on the surface of the carbon fiber thermal interface material;

[0027] Step 2: immersing the surface of the vapor chamber in a mercaptoethylamine-methyl mixed solution, and then drying to obtain a vapor chamber with a high molecular cured film attached thereto; wherein the surface of the high molecular cured film is attached with amino groups;

[0028] Step 3: attaching the surface of the carbon fiber thermal interface material prepared in step 1 to the surface of the vapor chamber prepared in step 2, and then pressing and baking to obtain a packaging structure for enhancing the thermal conduction of the interface between the carbon fiber thermal interface material and the vapor chamber.

[0029] Preferably, in step 1, the power of the plasma treatment is 100-500 W, and the time is 1-15 min; the gas of the plasma treatment is air or a mixed gas of oxygen and argon.

[0030] Preferably, the volume ratio of oxygen to argon is 5-15:95-85.

[0031] Preferably, in step 2, the concentration of mercaptoethylamine in the mercaptoethylamine-methyl mixed solution is 1-10 mM.

[0032] Preferably, in step 2, the temperature of the drying is 30-60℃, and the time of the drying is 10min-2h.

[0033] Preferably, in step 3, the temperature of the baking is 100-200℃, and the time of the baking is 10min-2h.

[0034] Preferably, in step 3, the pressure applied in the tabletting is 50-200 kPa.

[0035] Example 1

[0036] Step 1: the surface of the carbon fiber thermal interface material is treated by plasma to form carboxyl groups (-COOH) on the surface of the carbon fiber thermal interface material, the plasma treatment time is 5 min, the plasma treatment gas is a mixture of oxygen and argon, the ratio of oxygen to nitrogen is 5:95, and the plasma treatment power is 300W;

[0037] Step 2: immerse the surface of the gold-plated heat plate in a mercaptoethylamine-toluene mixed solution to obtain an immersed heat plate, the concentration of mercaptoethylamine is 1mM; dry the surface of the immersed heat plate to obtain a heat plate with a high-molecular solidification film attached to the surface, the surface of the film has an amino group, the drying temperature is 60℃, and the drying time is 10min;

[0038] Step 3: adhere the carbon fiber thermal interface material prepared in step 1 to the surface of the heat plate prepared in step 2, and after tabletting and baking, a covalent bond is formed at the interface between the carbon fiber thermal interface material and the heat plate, specifically, the carboxyl groups on the surface of the carbon fiber react with the amine groups on the surface of the heat plate to form amides, the drying temperature is 150℃, the drying time is 30min, and the applied pressure is 50kPa.

[0039] The surface of the carbon fiber thermal interface material of step 1 in this example is treated by plasma before and after plasma treatment, and the XPS of the surface of the carbon fiber thermal interface material before and after plasma treatment is shown in Figure 1 As shown in Figure 1 , the content of carboxyl groups on the surface of the carbon fiber thermal interface material after plasma treatment is increased from 4.3% to 13.3%.

[0040] The heat plate with a high-molecular solidification film attached to the surface of step 2 in this example 1 is subjected to infrared spectrum analysis, and the results are shown in Figure 2 As shown in Figure 2 , the gold-plated heat plate after mercaptoethylamine adsorption has a vibration absorption peak at 1657cm －1 , which is the vibration absorption peak of N-H, indicating that mercaptoethylamine is adsorbed on the gold-plated heat plate.

[0041] The surface of the carbon fiber thermal interface material in the packaging structure of step 3 in this example 1 is subjected to infrared spectrum analysis, and the results are shown in Figure 3As shown in Figure 3 It can be seen that the vibration peaks of amide appear at 1710 and 3410 cm -1 It can be seen that the vibration peaks of amide appear at 1710 and 3410 cm

[0042] Example 2

[0043] Step 1: The surface of the carbon fiber thermal interface material was treated using plasma to form carboxyl groups (-COOH) on the surface of the carbon fiber thermal interface material, the plasma treatment time was 3 min, the plasma treatment gas was a mixed gas of oxygen and argon, the ratio of oxygen to nitrogen was 10:90, and the plasma treatment power was 250 W;

[0044] Step 2: The surface of the gold-plated heat plate was immersed in a mercaptoethylamine-toluene mixed solution to obtain an immersed heat plate, and the concentration of mercaptoethylamine was 2 mM; the surface of the immersed heat plate was dried to obtain a heat plate with a polymer curing film attached to the surface, and the surface of the film had amino groups, the drying temperature was 60 ℃, and the drying time was 10 min;

[0045] Step 3: The carbon fiber thermal interface material prepared in step 1 was attached to the surface of the heat plate prepared in step 2, and after pressing and baking, a covalent bond was formed at the interface between the carbon fiber thermal interface material and the heat plate, specifically, the carboxyl groups on the surface of the carbon fiber reacted with the amine groups on the surface of the heat plate to form amide, the drying temperature was 150 ℃, the drying time was 30 min, and the applied pressure was 50 kPa.

[0046] Example 3

[0047] Step 1: The surface of the carbon fiber thermal interface material was treated using plasma to form carboxyl groups (-COOH) on the surface of the carbon fiber thermal interface material, the plasma treatment time was 3 min, the plasma treatment gas was a mixed gas of oxygen and argon, the ratio of oxygen to nitrogen was 5:95, and the plasma treatment power was 300 W;

[0048] Step 2: The surface of the gold-plated heat plate was immersed in a mercaptoethylamine-toluene mixed solution to obtain an immersed heat plate, and the concentration of mercaptoethylamine was 1 mM; the surface of the immersed heat plate was dried to obtain a heat plate with a polymer curing film attached to the surface, and the surface of the film had amino groups, the drying temperature was 40 ℃, and the drying time was 20 min;

[0049] Step 3: The carbon fiber thermal interface material prepared in step 1 was attached to the surface of the heat plate prepared in step 2, and after pressing and baking, a covalent bond was formed at the interface between the carbon fiber thermal interface material and the heat plate, specifically, the carboxyl groups on the surface of the carbon fiber reacted with the amine groups on the surface of the heat plate to form amide, the drying temperature was 150 ℃, the drying time was 30 min, and the applied pressure was 50 kPa.

[0050] Comparative Example 1

[0051] The untreated carbon fiber thermal interface material and the untreated vapor chamber are directly attached, and after tabletting and baking, the encapsulated structure is obtained. The parameters of the same steps as in Example 1 are the same as in Example 1.

[0052] Comparative Example 2

[0053] The carbon fiber thermal interface material is treated according to Example 1, the gold-plated vapor chamber is not treated according to Example 1, the treated carbon fiber thermal interface material is attached to the untreated gold-plated vapor chamber, and after tabletting and baking, the encapsulated structure is obtained. The parameters of the same steps as in Example 1 are the same as in Example 1.

[0054] Comparative Example 3

[0055] The carbon fiber thermal interface material is not treated according to Example 1, the gold-plated vapor chamber is treated according to Example 1, the untreated carbon fiber thermal interface material is attached to the treated gold-plated vapor chamber, and after tabletting and baking, the encapsulated structure is obtained. The parameters of the same steps as in Example 1 are the same as in Example 1.

[0056] Performance inspection and result analysis:

[0057] The encapsulated structures prepared from Example 1, Comparative Example 1, Comparative Example 2 and Comparative Example 3 are subjected to thermal resistance (LW-9389 test equipment) and interface bonding strength detection. After detection, the thermal resistance of Example 1 is 0.342℃ / W, the thermal resistance of Comparative Example 1 is 0.398℃ / W, the thermal resistance of Comparative Example 2 is 0.402℃ / W, and the thermal resistance of Comparative Example 3 is 0.476℃ / W. Therefore, the scheme of the present application can reduce the thermal resistance of the vapor chamber and the thermal interface material, thereby improving the thermal conductivity of the encapsulated module; the interface bonding strength of Example 1 is increased by 44%, 51% and 58% compared with Comparative Example 1, Comparative Example 2 and Comparative Example 3. Therefore, it is shown that the encapsulated module formed by the vapor chamber and the thermal interface material of the present application has improved thermal conductivity, and the interface bonding strength of the vapor chamber and the thermal interface material is also significantly improved, thereby improving the heat dissipation performance and reliability.

[0058] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or replacements within the scope of the disclosed technology can be easily thought of by those skilled in the art, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for producing a package structure for enhancing thermal conduction at the interface between a carbon fiber thermal interface material and a vapor chamber, characterized by The method comprises the following steps: Step 1: treating the surface of the carbon fiber thermal interface material using plasma to form carboxyl on the surface of the carbon fiber thermal interface material; Step 2: immersing the surface of the vapor chamber in a mercaptoethylamine-methyl mixed solution, and then drying to obtain a vapor chamber with a polymer curing film attached thereto; wherein the surface of the polymer curing film is attached with amino groups; Step 3: attaching the surface of the carbon fiber thermal interface material prepared in step 1 to the surface of the vapor chamber prepared in step 2, and then pressing and baking to make the carboxyl on the surface of the carbon fiber thermal interface material react with the amino groups on the surface of the vapor chamber to form amide bonds, thereby realizing the direct covalent connection between the carbon fiber thermal interface material and the vapor chamber, and obtaining an encapsulation structure for enhancing the interfacial thermal conduction between the carbon fiber thermal interface material and the vapor chamber.

2. The method of claim 1, wherein the method is characterized by: In step 1, the power of the plasma treatment is 100-500 W, and the time is 1-15 min; the gas of the plasma treatment is air or a mixed gas of oxygen and argon.

3. The method of claim 2, wherein the method further comprises the steps of: applying a carbon fiber thermal interface material to the surface of the heat spreader; and applying a carbon fiber thermal interface material to the surface of the heat spreader. The volume ratio of oxygen to argon is 5-15:95-85.

4. The method of claim 1, wherein the method is characterized by: In step 2, the concentration of mercaptoethylamine in the mercaptoethylamine-methyl mixed solution is 1-10 mM.

5. The method of claim 1, wherein the method further comprises the steps of: applying a carbon fiber thermal interface material to the surface of the heat spreader; and applying a carbon fiber thermal interface material to the surface of the heat-generating component. In step 2, the drying temperature is 30-60℃, and the drying time is 10 min-2 h.

6. The method of claim 1, wherein the method is characterized by: In step 3, the baking temperature is 100-200℃, and the baking time is 10 min-2 h.

7. The method of claim 1, wherein the method further comprises the steps of: applying a carbon fiber thermal interface material to the surface of the heat spreader; and applying a carbon fiber thermal interface material to the surface of the heat generating component. In step 3, the pressure applied by the pressing is 50-200 kPa.

8. An encapsulation structure for enhancing the interfacial thermal conduction between a carbon fiber thermal interface material and a vapor chamber, which is prepared by the method according to any one of claims 1-7.

9. The package structure of claim 8, wherein The carbon fiber thermal interface material and the vapor chamber are connected through amide bonds.

Images