TWI711135B - Die heat dissipation structure - Google Patents

Abstract

A heat dissipation structure for a bare crystal includes a heat dissipation unit and a bare crystal. The heat dissipation unit has a first side and a second side. A contact portion is protrudingly formed on the second side, and one end of the contact portion is a Slightly convexly curved surface, the bare die has an upper surface and a lower surface, one end of the contact portion is in contact with the upper surface, and the upper surface is in a slightly concavely curved surface for contact with the contact portion Slightly convex surface appearance matches.

Description

Die heat dissipation structure

The present invention relates to a heat dissipation structure of a bare crystal, in particular to a heat dissipation structure of a bare crystal that can greatly reduce the thermal resistance problem and effectively improve the heat dissipation efficiency.

The semiconductor integrated circuit industry has experienced rapid growth. The technological progress in semiconductor integrated circuit materials and design has produced multiple generations of semiconductor integrated circuits. Each generation of semiconductor integrated circuits is smaller and smaller than the previous generation of semiconductor integrated circuits. More complex circuits, however, these advances have also increased the complexity of processing and manufacturing semiconductor integrated circuits. The traditional chip system includes die and package shell. Usually the die and package shell are combined by indium welding or other bonding methods. However, this structural design will cause the interface between the die and the package shell to be heated. The resistance is very large. Therefore, in recent years, with the increase of power and heat flow density, in order to effectively improve the heat dissipation efficiency of the chip, the chip factory has eliminated the package shell components that cover the chip in the design, and wants to reduce the package shell material The thermal resistance of the main body and the thermal resistance of the interface material have become the design mode of the structure of the bare crystal, thermal paste and heat sink. However, due to the flatness of the bare silicon material of this design, the weight of the heat sink, and the fastening force The requirements are relatively high. When the die is working at a high temperature, it will deform, making the surface of the die appear a slightly concave curved shape, resulting in a gap when it is in contact with the heat sink and there is still a thermal resistance problem, which makes the die The heat cannot be quickly taken away by the radiator, resulting in a very limited improvement in heat dissipation efficiency. As mentioned above, conventional knowledge has the following shortcomings: 1. Serious thermal resistance problem; 2. Poor heat dissipation efficiency. Therefore, how to solve the above-mentioned conventional problems and deficiencies is the direction that the inventor of this case and the related manufacturers engaged in this industry urgently want to study and improve.

Therefore, in order to effectively solve the above-mentioned problems, the main purpose of the present invention is to provide a heat dissipation structure for bare crystals that greatly reduces the thermal resistance problem. The secondary objective of the present invention is to provide a heat dissipation structure of a bare die with greatly improved heat dissipation efficiency. To achieve the above objective, the present invention provides a heat dissipation structure of a bare die, which includes a heat dissipation unit and a bare die. The heat dissipation unit has a first side and a second side, and a contact is protrudingly formed on the second side. Portion (ie, the contact portion 210 is formed on the surface of the protrusion on the second side 21 of the heat dissipation unit), one end of the contact portion is in the form of a slightly convex curved surface, the die has an upper surface and a lower surface, the contact portion One end is in contact with the upper surface, and the upper surface is in a slightly concave curved surface to match the slightly convex curved surface of the contact portion. Through the design of the structure of the present invention, heat will be generated when the die starts to work, so that the top surface of the die will be deformed at a high temperature to present a slightly concave curved surface. The contact portion of the heat dissipation unit The structure at one end is in the form of a slightly convex curved surface, so that the upper surface of the die can be completely contacted and attached to the contact part, which effectively reduces the thermal resistance problem, so that the heat on the die can be quickly dissipated by the heat The unit is separated, which greatly improves the heat dissipation efficiency.

The above-mentioned objects and structural and functional characteristics of the present invention will be described based on the preferred embodiments of the accompanying drawings. Please refer to Figures 1 and 2, which are an exploded view and an enlarged schematic view of the heat dissipation structure of the die of the present invention. As shown in the figure, a heat dissipation structure of a die includes a heat dissipation unit 2 and a die 3. The The heat dissipating unit 2 is a heat sink, a heat dissipating base, a temperature equalizing plate and other components capable of dissipating heat. It has a first side 20 and a second side 21. A plurality of heat dissipating fins 200 are formed on the first side 20 A contact portion 210 is protrudingly formed on the second side 21 (that is, the contact portion 210 is formed on the surface of the protrusion of the second side 21 of the heat dissipation unit), and one end of the contact portion 210 is in a slightly convex curved shape. In this embodiment, the contact portion 210 and the heat dissipation unit 2 are described as being integrally formed, but it is not limited to this, and the user can also make the contact portion 210 and the heat dissipation unit 2 non-integrally formed according to usage requirements. And the contact portion 210 and the heat dissipation unit 2 are selected to be made of silver, copper, aluminum, iron or other high thermal conductivity materials. The contact portion 210 and the heat dissipation unit 2 can be made of the same material or different materials. Bright. The die 3 has an upper surface 30 and a lower surface 31, one end of the contact portion 210 is in contact with the upper surface 30, and the upper surface 30 is in a slightly concave curved shape to be in contact with the The slightly convex curved surface of the portion 210 matches, and the lower surface 31 is correspondingly installed on a substrate 4. Continuing to refer to Figure 2, a micro gap (not shown in the figure) is formed between the contact surface of the heat dissipation unit 2 and the die 3 of the present invention. The micro gap is correspondingly coated with a thermally conductive coating 32. The thermally conductive coating The layer 32 is a thermal grease, a thermally conductive glue, and a thermally conductive pad, and the thermally conductive coating 32 is used to more closely fill the micro-gap in order to avoid the formation of the aforementioned micro-gap and cause thermal resistance. Therefore, through the design of the structure of the present invention, when the die 3 starts to work, heat will be generated to make the die 3 gradually heat up, and due to factors such as the material of the die 3 and its manufacturing process, the die 3 Deformation occurs in a high temperature state, that is, the deformation at the center of the upper surface 30 of the bare die 3 gradually dents and presents a slightly concave curved surface. At this time, the structure at one end of the contact portion 210 of the heat sink 2 is A slightly convex curved surface, and the shape of the slightly convex curved surface and the slightly concave curved surface are completely matched, so that the contact portion 210 and the upper surface 30 of the die 3 are completely contacted and attached. , It can improve the thermal resistance problem caused by the gap generated when the contact interface of the conventional heat dissipation unit is planar and the upper surface of the deformed bare die contacting and bonding. The present invention effectively improves the thermal resistance problem of the conventional structure, and then The heat reaching the die 3 can be quickly removed by the heat dissipation unit 2, which greatly improves the heat dissipation efficiency. It should be noted that since the deformation (dimple curved surface state) produced by the upper surface 30 of the bare die 3 is very small, the deformation is usually in the order of micrometers ( ㎛ ), so the curvature of the deformation is between 50 ㎛ ～70 ㎛ , and the drawing shown in the present invention is illustrated by magnification several times, so that the structural design of the present invention can be more clearly understood. The curvature of the slightly convex surface of the contact portion 210 of the heat dissipation unit 2 is also equivalent The second side 21 of the heat dissipating unit 2 usually chooses to use a grinding process to make the contact portion 210 appear a slightly convex curved surface because it is a curved arc on the order of micrometers ( ㎛ ). The manufacturing method of the curved surface is not limited to grinding processing, CNC processing, planing processing or other processing methods can also be used. As mentioned above, the present invention has the following advantages compared with the prior art: 1. The problem of thermal resistance is greatly reduced; 2. The heat dissipation efficiency is greatly improved. The present invention has been described in detail above, but what is described above is only a preferred embodiment of the present invention, and should not limit the scope of implementation of the present invention, that is, all equivalent changes and modifications made in accordance with the scope of application of the present invention Etc., should still be covered by the patent of the present invention.

2: Cooling unit 20: First side 200: cooling fins 21: second side 210: Contact 3: bare die 30: upper surface 31: lower surface 32: Thermally conductive coating 4: substrate

Figure 1 is an exploded view of the heat dissipation structure of the die of the present invention; Figure 2 is an enlarged schematic diagram of the heat dissipation structure of the bare die of the present invention.

2: Cooling unit

20: First side

200: cooling fins

21: second side

210: Contact

3: bare die

30: upper surface

31: lower surface

4: substrate

Claims (7)

A heat dissipation structure for bare crystals, including: A heat dissipation unit having a first side and a second side, a contact portion is convexly formed on the second side, and one end of the contact portion is a slightly convex curved surface; and A bare chip has an upper surface and a lower surface, one end of the contact part is in contact with the upper surface, and the upper surface is a slightly concave curved surface to match the slightly convex curved surface of the contact part. The heat dissipation structure of the bare die according to claim 1, wherein a micro gap is formed between the heat dissipation unit and the bare die, and a thermally conductive coating is applied to the micro gap. The heat dissipation structure of the bare die according to claim 1, wherein the contact portion and the heat dissipation unit are formed integrally or non-integrally. The heat dissipation structure of the bare crystal according to claim 1, wherein the curvature of the slightly convex curved surface and the slightly concave curved surface is between 0.05 mm and 0.07 mm. The heat dissipation structure of the bare crystal according to claim 1, wherein the heat dissipation unit is further formed with a plurality of heat dissipation fins, and the heat dissipation fins are arranged at intervals on the first side. The heat dissipation structure of the bare die according to claim 1, wherein the lower surface of the bare die is correspondingly installed on a substrate. In the heat dissipation structure of the bare die as described in claim 1, wherein the contact portion of the heat dissipation unit is processed to make one end of the contact portion a slightly convex curved surface.

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