JPS59205742A - Semiconductor cooling device - Google Patents

Abstract

PURPOSE:To facilitate the assembly operation as well as to obtain the high-reliability semiconductor cooling device by brazing blocks of Cu, Al and so on with the both pressure-contact planes of the insulating sheet to form them into a disc shape unitarily. CONSTITUTION:Blocks of Cu, Al and so on 11a and 11b are brazed onto both pressure-contact planes 12a and 12b of an insulating sheet 2 made of ceramic or the like. The blocks 11a and 11b are provided with a hole 13 for adjusting the centers to those of flat semiconductor elements. When the insulating disc thus formed unitarily is fixed between the flat semiconductor elements and the cooling blocks, heat transfer efficiency is extremely improved thereby facilitating the assembly operation and offering the high-reliability semiconductor cooling device.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor cooling device, and more particularly to an insulating disk that can efficiently transfer heat loss and insulate semiconductor elements, and facilitate assembly work.

A conventional device of this type is shown in FIG. In the figure, 1 is a flat semiconductor element and 2a.

2 and b are terminal plates that contact and connect to the anode and cathode surfaces of this flat semiconductor element 1 to extract electricity; 3 is this terminal plate 2a;
and the flat semiconductor 1, and electrically insulates the element 1 and the cooling block 4. 5 is an insulating seat, 6 is a pressurized dust, 7 is a spring plate, 8 is a tightening bolt, 9 is a bolt, and 10 is a metal ball arranged between this port 10 and the pressurized dust 6.

Next, the operation will be explained.

Normally, when current is applied to the flat semiconductor element 1, heat is generated due to internal loss of the element 1. Since this heat loss is dissipated from the anode and cathode surfaces of the element 1, the cooling block 4 is pressure welded to either the pole surfaces of the element 1, or to either one of the pole surfaces, and the loss heat is transferred to a secondary cooling medium such as air. Exchange. At this time, if there is no insulating sheet 3 as shown in FIG. 1, the cooling block 4 is directly press-connected to the element 1, so it will be charged with the potential of the element 1, which may cause electrical insulation to deteriorate or In order to prevent danger, they were often housed in a cubicle with a housing structure. However, in order to suppress the temperature rise inside the cubicle, it was necessary to bring in outside air, which caused problems in maintenance and inspections. Recently, as shown in FIG. 1, electrical insulation between the flat semiconductor element 1 and the cooling block 4 has been improved.
A method is used in which this is done using an insulating sheet 3 placed outside the housing cubicle. This insulating sheet 3 is made of an excellent material that can provide electrical insulation and efficiently transmit the heat loss of the element 1 to the cooling block 4, and must be extremely thin and formed into a circular or rectangular sheet shape. .

Since the conventional semiconductor cooling device is constructed as described above, the ultra-thin insulating sheet 3 must be inserted and pressed between the cooling block 4 and the flat semiconductor element 1 for insulation.
It is extremely difficult to process the press-contact surface of the cooling block 4 and assemble it, such as centering the element 1 and the insulating sheet 3, and applying conductive grease to reduce contact thermal resistance. Because it is extremely thin, it has the disadvantage that it is extremely difficult to handle, as care must be taken to prevent cracks.

This invention was made to eliminate the above-mentioned drawbacks of the conventional method. Blocks of copper, aluminum, etc. are bonded to both tangential surfaces of an insulating sheet by brazing or soldering, etc., and a disc-shaped The object of the present invention is to provide a highly reliable semiconductor cooling device that improves assembly workability and thermal conductivity by integrally forming the semiconductor cooling device.

An embodiment of the present invention will be described below with reference to the drawings. Second
In the drawings and FIG. 3, reference numeral 2 denotes the above-mentioned insulating sheet, which is made of, for example, ceramic. 11a and llb are copper pieces fixed to both pressure-contact surfaces of the insulating sheet 20 by brazing, soldering, or the like.

Blocks such as aluminum, 12a and 12b are brazed or soldered surfaces, and 13 are blocks 11a and 11
This is a hole formed in b for center alignment with the flat semiconductor element 1.

According to the above configuration, the thin insulating sheet 2 and the blocks 11a, 11b that are brazed or soldered to the thin insulating sheet 2 are fixed.
An integrated insulating disk will be constructed. With this structure, electrical insulation between the flat semiconductor element 1 and the cooling block 4 and loss heat transfer of the element 1 can be achieved extremely efficiently. Furthermore, conventionally, the thickness of the insulating sheet 2 is about 1 to 2 mm, and the pressure force between the flat semiconductor element 1 and the cooling block 4 is 100 mm.
Due to the extremely large size of approximately 0 to 4oooKy, there were drawbacks such as damage to the insulating sheet due to the adhesion of dust and other impurities to the pressure contact surface, and an increase in contact thermal resistance on both sides of the insulating sheet when combined. Since the blocks 11a, 11b made of copper, aluminum, etc. are fixedly integrated with the block 2, this problem can be reliably solved. Furthermore, the above block 11
Since holes 13 for center alignment were formed in a and 11b,
During assembly work, the insulating sheet 2 can be easily inserted and installed without causing difficulty in centering the insulating sheet 2, deviation, twisting, etc. as in the conventional case. Moreover, when the insulating sheet 2 and the blocks 11a, 11b are brazed or soldered, the holes 13 serve as an escape port for air bubbles on the contact surface, and a contact surface with good adhesion can be obtained, resulting in a contact thermal resistance. It is useful for producing insulating disks with low thermal conductivity.

FIG. 4 shows another embodiment of the present invention, in which the present invention is applied to a circuit constituting a part of a flat semiconductor device. In the figure, la and ib are main thyristors through which a large current flows, and flat semiconductor elements of, for example, 1000 A class are used. 14a, j4b are main thyristors 1a,
An auxiliary diode connected in antiparallel to 1b to bypass the reactive current, for example a flat semiconductor element of the 3008 class, is used. 15a and 15b are snubber resistors, 1
6a, 16b are snubber capacitors, 17a, 17b
is a snubber diode. Since the snubber diodes 17a and 17b, which have relatively small capacitance, have a small loss of heat, they can be attached to a steel material having the same potential bonded to the insulating sheet 2 of the above embodiment.

FIGS. 5 and 6 also show other embodiments of the invention. It is an insulating disk in which a block 19 of copper, aluminum, etc., having a mounting hole 18 for mounting the snubber diode, etc., as shown in the figure, is brazed or soldered to an insulating sheet 2. 18 is the bolt hole for installing the Svaner diode,
Numeral 20 is a bolt for taking out electricity from the anode and cathode surfaces of the flat semiconductor element, and has the same effect as described above.

As described above, according to the present invention, since the insulating disk is formed by integrating the insulating sheet and the block made of copper, aluminum, etc., the thermal conductivity is dramatically improved, and the assembly work etc. is extremely simple. This has the effect of providing a highly reliable semiconductor cooling device.

[Brief explanation of the drawing]

Fig. 1 is a side view of a conventional semiconductor cooling device, Fig. 2 is a plan view of an embodiment of the present invention, Fig. 3 is a longitudinal sectional view taken along line A-A in Fig. 2, and Fig. 4 is a general flat type. Another embodiment in which the present invention is applied to a semiconductor circuit constituting a part of a semiconductor device, FIG. 5 shows another embodiment of the present invention, and FIG. 6 shows a B-Bi longitudinal cross-sectional view of FIG. 5. DESCRIPTION OF SYMBOLS 1... Semiconductor element (flat semiconductor element), 3... Insulating sheet, 4... Cooling piece, 11a, 1lb-block of copper, aluminum, etc. In the figures, the same reference numerals indicate the same or corresponding parts. Φ Fig. 2 Fig. 3 Fig. 4 Prisoner No. 5 Fig. 6 (2) 1b Procedural amendment (voluntary) 581021 Showa year Date Date Mr. Commissioner of the Japan Patent Office 3. Relationship with the person making the amendment Patent applicant representative Katayama Part 4, Agent-9 -...'1゛＼ 5, Column 6 for detailed explanation of the invention in the specification subject to amendment, Lines 3 to 5 on page 3 of the specification of the contents of the amendment The line ``method performed using an insulating sheet 6 placed outside the housing cubicle'' is corrected to read ``a method in which the cooling block is electrically insulated from the element 1 and placed outside the housing cubicle''. that's all

Claims (1)

[Scope of Claims] A semiconductor cooling device that performs cooling by placing a cooling piece in contact with one pole surface of a semiconductor element, wherein copper, aluminum, etc. are provided on both sides of an insulating sheet between the semiconductor element and the cooling piece. A semiconductor cooling device characterized by having an integrated insulating disk arranged by fixing the blocks. (2) The semiconductor cooling device according to claim 1, wherein a hole for centering is provided in the block of copper, aluminum, etc. of the insulating disk.