CN-122030000-A - Ceramic insulating substrate

CN122030000ACN 122030000 ACN122030000 ACN 122030000ACN-122030000-A

Abstract

The ceramic insulating substrate comprises a ceramic substrate, a first metal layer arranged on the upper surface of the ceramic substrate, a second metal layer arranged below the ceramic substrate, wherein the second metal layer is partially arranged below the ceramic substrate, and a third metal layer arranged on the lower side of the second metal layer, and the second metal layer is arranged so that part of the lower surface of the ceramic substrate can be directly exposed to air.

Inventors

GUO WANXI
Jin Fugeng

Assignees

株式会社KCC

Dates

Publication Date: 20260512
Application Date: 20241007
Priority Date: 20231012

Claims (8)

1. A ceramic insulating substrate, comprising: A ceramic substrate; a first metal layer provided on the ceramic substrate; A second metal layer disposed under the ceramic substrate, the second metal layer being partially disposed under the ceramic substrate, and A third metal layer disposed under the second metal layer, The second metal layer is arranged such that a portion of the underside of the ceramic substrate is directly exposed to air.
2. The ceramic insulating substrate according to claim 1, wherein, The second metal layer is formed so that air can flow from one point of the corners of the lower surface of the ceramic substrate across the inside of the lower surface of the ceramic substrate to another point of the corners of the lower surface of the ceramic substrate.
3. The ceramic insulating substrate according to claim 1, wherein, The second metal layer is formed with a plurality of blocks arranged to be spaced apart from each other.
4. The ceramic insulating substrate according to claim 3, wherein, The thickness of the second metal layer is 1 to 2 times that of the first metal layer.
5. The ceramic insulating substrate according to claim 3, wherein, The second metal layer has a block pitch of 0.5 to 1.5 times the thickness of the second metal layer.
6. The ceramic insulating substrate according to claim 3, wherein, The total area of the second metal layer is 40 to 80% of the area of the third metal layer.
7. The ceramic insulating substrate according to claim 3, wherein, The third metal layer is formed in an area corresponding to the outer periphery of the entire second metal layer and integrally bonded to the entire second metal layer.
8. The ceramic insulating substrate according to claim 3, wherein, Is designed to mount a semiconductor chip on the upper side of the first metal layer, The second metal layer is formed so that a region corresponding to the region where the semiconductor chip is mounted has a wider area than other regions or has an area corresponding to the semiconductor chip.

Description

Ceramic insulating substrate Technical Field The present invention relates to a ceramic insulating substrate. Background Ceramic insulating substrates have a small deformation ratio at high temperature and excellent insulation properties at high voltage, and are therefore often used for high-power inverters and converter power modules. The ceramic insulating substrate can be classified into DCB (Direct Copper Bonding ), AMB (ACTIVE METAL Brazing, active metal brazing), and the like according to a method of bonding copper. On the other hand, the power module generates a lot of heat in the semiconductor element during operation, and this heat generation problem causes switching loss, thereby degrading product performance, and in the case of the silicon semiconductor element, the semiconductor property may be lost above 150 ℃. In manufacturing a power module, a substrate of various materials can be bonded to each other, but when there are a plurality of boundary surfaces between the materials, the thickness becomes thick, and thus not only is it difficult to achieve miniaturization, but also the heat dissipation effect is reduced due to thermal resistance, and therefore a technique for dissipating heat with a minimum of substrates is required. For example, korean laid-open patent publication No. 10-2018-0059778 discloses a structure having heat dissipation pins on a corresponding substrate. However, this approach relies only on conduction to transfer heat to the heat sink pins, and thus has limitations in heat dissipation performance. Disclosure of Invention Problems to be solved by the invention The invention aims to provide a ceramic insulating substrate capable of effectively radiating heat. Measures taken to solve the problems The ceramic insulating substrate comprises a ceramic substrate, a first metal layer arranged on the upper surface of the ceramic substrate, a second metal layer arranged below the ceramic substrate, wherein the second metal layer is partially arranged below the ceramic substrate, and a third metal layer arranged on the lower side of the second metal layer, and the second metal layer is arranged so that part of the lower surface of the ceramic substrate can be directly exposed to air. The second metal layer may be formed so that air can flow from any one point of the corners of the lower surface of the ceramic substrate across the inside of the lower surface of the ceramic substrate to another point of the corners of the lower surface of the ceramic substrate. The second metal layer may be formed of a plurality of blocks arranged to be spaced apart from each other. In addition, the thickness of the second metal layer may be 1 to 2 times the thickness of the first metal layer. In addition, the pitch of the blocks of the second metal layer may be 0.5 to 1.5 times the thickness of the second metal layer. In addition, the total area of the second metal layer may be 40 to 80% of the area of the third metal layer. The third metal layer may be formed in an area corresponding to the outer periphery of the entire second metal layer and integrally bonded to the entire second metal layer. In addition, the semiconductor chip is mounted on the upper side of the first metal layer, and the second metal layer may be formed so that a region corresponding to the region where the semiconductor chip is mounted has a wider area than other regions or has an area corresponding to the semiconductor chip. ADVANTAGEOUS EFFECTS OF INVENTION In the ceramic insulating substrate according to the present invention, the second metal layer is partially disposed under the ceramic substrate, so that in the ceramic base material, together with heat dissipation by conduction through the second metal layer and the third metal layer, between adjacent blocks of the second metal layer, the under side of the ceramic base material is directly exposed to air, that is, air can flow between adjacent blocks of the second metal layer, and therefore, heat dissipation can be more rapidly and effectively performed by convection caused by the air. Drawings Fig. 1 is a perspective view of a ceramic insulating substrate according to one embodiment of the present invention. Fig. 2 shows the morphology of fig. 1 after removal of the first metal layer and the ceramic substrate. Fig. 3 is a side view of a ceramic insulating substrate according to one embodiment of the invention. Fig. 4 shows an enlarged form of the IV portion in fig. 3. Fig. 5 relates to a ceramic insulating substrate according to another embodiment of the invention, which shows a morphology corresponding to fig. 2. Fig. 6 relates to a ceramic insulating substrate according to a further embodiment of the invention, which shows a morphology corresponding to fig. 2. Detailed Description A ceramic insulating substrate 10 according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 is a perspective view of a