JPS61218148A - Heat sink controller of semiconductor device - Google Patents

Abstract

PURPOSE:To improve the sealability by sealing grooves at least with any of a heat sink metal plate contacted with the back surface of a substrate and the substrate, providing corners in the section, and providing a coolant passage sealed with coolant, thereby readily sealing the coolant. CONSTITUTION:A substrate 1 is formed of a ceramic material for placing an IC chip A of a semiconductor device. A heat sink metal plate 2 of copper is contacted fixedly with the back surface of a chip A placing surface. Several fine grooves 4 are formed in parallel on the back surface of the substrate 1 contacted with the plate 2, and formed by sealing with the plate 2 in the coolant passage 3 of the square-sectional shape. Coolant 5 is sealed in the passage 3, and collected at the corner 3a of the passage 3 due to a capillary phenomenon at ambient temperature. Thus, since a pipe for sealing the coolant 5 can be connected with the passage 3, the sealability and the sealing of the coolant can be facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a heat radiation control device that improves the heat radiation performance of a semiconductor device in which a semiconductor element such as an IC is attached to a substrate.

(Technical background of the invention and its problems) Conventionally, as this type of heat radiation control device, for example, JAT
Published by EC Rcsearch and D e
Valopmer+t or Heat p t
-r, P. Cotter, rPRI, published in pe Techno+ogy J, pages 328 to 335.
NGIPI4s AND PRO3PECTS
There is a so-called micro heat pipe described in FORMICRO) IEAT PIPESJ. In other words, this method involves applying an oxide film to a silicon substrate, etching the oxide film to form a groove with a triangular or square cross section, and sealing the oxide film with heat-resistant glass that serves as a heat dissipation plate to allow refrigerant to flow through the groove. A refrigerant was sealed in the tube. Therefore, even if the semiconductor element heats up locally, the refrigerant in the cooling 1s flow path formed by sealing the groove evaporates in the heating section, and the refrigerant condensed in the low temperature section covers the corners of the refrigerant flow path. The heat flows into the heating section by capillary action through the silicon substrate, and heat dissipation is controlled so that the temperature is uniform throughout the silicon substrate. By the way, since the grooves are sealed with heat-resistant glass, it is difficult to seal the refrigerant into the refrigerant flow passages after the grooves have been sealed. must be enclosed. However, refrigerant has a high vapor pressure at room temperature, so if you try to seal it into the groove using this method, you have to do it at a very low temperature with no vapor pressure, which is not only extremely difficult. However, there are problems in that the sealing performance is poor and the reliability is low.

(Object of the Invention) The present invention has been devised in view of the above-mentioned problems, and enables the refrigerant to be sealed after forming the refrigerant flow path by sealing the groove, is easy to manufacture, and has excellent sealing properties. It is an object of the present invention to provide a heat radiation control device for a semiconductor device that can improve reliability.

(Summary of the Invention) The present invention provides a substrate on which a semiconductor is mounted, a metal plate for heat dissipation closely attached to the back surface of the substrate, and a groove portion formed in at least one of the contact surfaces of the substrate and the metal plate. The structure includes a refrigerant flow path that is sealed, has a corner in its cross section, and seals a refrigerant.

(Example of the invention) An embodiment of the present invention will be described based on the drawings.

The substrate 1 is used to mount an ICC chip, which is a semiconductor element of a semiconductor device, and is made of a ceramic material.The substrate 1 has a metal plate 2 for heat dissipation made of a copper plate on the opposite side (back side) to the surface on which the IC chip A is mounted. It is tightly fixed. In addition, several fine grooves 4 are carved in parallel on the back surface of the substrate 1 to which the metal plate 2 is in close contact, and the grooves 4 are sealed with the metal plate 2 to form a coolant flow path 3 having a rectangular cross-sectional view. has been done. The sealed refrigerant flow path 3 is filled with cold water, and at room temperature, due to capillary action, the corner 3a of the refrigerant flow path 3
are aggregated.

Next, the manufacturing method will be explained.

First, a plurality of fine grooves 4 are formed in parallel on the back surface of a substrate 1 made of a ceramic material by etching, machining, or laser beam processing. Next, the metal plate 2 is bonded to the back surface where the groove portion 4 is located by diffusion welding by heating at a high temperature for a long time while making light contact with a small pressure force. When the substrate 1 and the metal plate 2 are joined, the substrate 1
The back side of the refrigerant flow path 3 is completely sealed, and the groove 4 is sealed to form a refrigerant flow path 3. Thereafter, a pipe (not shown) communicating with the refrigerant flow path 3 is connected to the metal plate 2 by machining. The pipe is a thin tube at the point where it connects to the metal plate 2, and is formed into a large tube from the middle, and a pulp is attached to the thick tube, and it communicates with a refrigerant injection device (not shown) through this pulp. It is connected. After connecting the pipe to the heat sink 2, the refrigerant injection device is operated to seal the refrigerant 5 into the refrigerant flow path 3 through the pipe under pressure. At this time, the cold [5] condenses at the corner 3a of the refrigerant flow path 3 due to capillary action. After the refrigerant 5 has been filled into the refrigerant flow path 3, the pipe is closed by squeezing it at the thin tube while maintaining the pressurized state. When cutting and removing and welding the cut parts, the substrate 1, metal plate 2, refrigerant flow path 3, and refrigerant 5 are removed.
A micro heat pipe is constructed. In this way, the metal plate 2 is in close contact with the back surface of the substrate 1, and the - groove portion 4
After the refrigerant flow passage 3 is sealed, a pipe for enclosing cold air filter 15 can be connected to this refrigerant flow passage 3, so the refrigerant must be sealed in the groove at the same time as the conventional glass seal. Compared to conventional products, sealing and refrigerant encapsulation can be performed much more easily, and the sealing performance can be improved and reliability can be improved.

In the micro heat vib configured in this way, when the temperature distribution becomes extremely uneven due to the thickness of the ICC chip, the refrigerant 5 evaporates in the high temperature part and becomes a gas, passing through the central part 3b of the refrigerant flow path 3. Move to a cold area. The refrigerant 5 that has moved to the low temperature section condenses into a liquid, aggregates at the corner 3a, and returns to the high temperature section due to capillary action. Along with this circulation movement of the coolant 5, the heat generated in the ICC chip thickness is dissipated by the heat dissipation of the metal plate 2, and the IC chip Δ is controlled to a uniform temperature as a whole, so that the ICC chip operates in a good condition with a good thickness. be able to.

Note that the groove portion 4 may be provided on the metal plate 2 side as shown in FIG. 3, or may be provided on both the substrate 1 and the metal plate 2.

Furthermore, as shown in FIG. 4, fins 6 may be attached to the metal plate 2 to improve heat dissipation efficiency.

Further, although the refrigerant flow passage 3 in this embodiment is shown as having a rectangular shape, it is not limited to this; in addition to a triangular one as shown in FIG. The refrigerant 4 may be of an amorphous shape, and essentially has corners, and is liquefied on the low temperature side due to capillary action at the corners.
It is sufficient if the temperature returns to the high temperature side again.

In addition, although several grooves 4 are shown in parallel, they may be formed into a cross-shaped groove, one groove, or several grooves in a cross-shaped groove as appropriate.

(Effects of the Invention) As is clear from the above, according to the present invention, the substrate is in close contact with the metal plate, and there is no need to seal the refrigerant in the groove with a seal, and the groove is sealed to form a refrigerant flow path. After that, the refrigerant can be sealed in the refrigerant inlet passage, so the refrigerant can be sealed very easily without using any particularly difficult means, and the sealing performance can be improved and reliability can be increased. can.

[Brief explanation of the drawing]

FIG. 1 is an overall sectional view of a micro heat vibrator which is an embodiment of the heat dissipation control device for a semiconductor device according to the present invention, FIG. 2 is a sectional view of the same essential part, and FIGS. It is a sectional view showing an example. A... IC chip 1... Substrate 2... Metal plate 3... Refrigerant flow path 3a... Corner
4... Groove 5... Refrigerant Figure 1 Figure 2 Figure 3 Δ

Claims (1)

[Claims] A substrate on which a semiconductor is mounted, a metal plate for heat dissipation closely attached to the back surface of this substrate, and a groove formed in at least one of the contact surfaces of the substrate and the metal plate are sealed with the other side. A heat radiation control device for a semiconductor device comprising a refrigerant flow path that has a corner in its cross section and seals a refrigerant.