CN202275814U

CN202275814U - Metal-clad ceramic substrate

Info

Publication number: CN202275814U
Application number: CN 201120329906
Authority: CN
Inventors: 王涛; 王晓宝; 姚天宝; 郑军
Original assignee: Jiangsu Macmic Science & Technology Co Ltd
Current assignee: Macmic Science and Technology Co Ltd
Priority date: 2011-09-03
Filing date: 2011-09-03
Publication date: 2012-06-13
Anticipated expiration: 2021-09-03

Abstract

The utility model relates to a metal-clad ceramic substrate, comprising a ceramic substrate and metal layers coated on the upper and lower two surfaces of the ceramic substrate. A spacing d is existed between the peripheral faces of the metal layers and the peripheral face of the ceramic substrate, and the peripheral faces of the metal layers at least comprise a thinning annular step surface. In the utility model, by forming at least one thinning annular step surface at the peripheries of the two metal layers, and by thinning the edge thicknesses of the metal layers on the metal-clad ceramic substrate, the step surface can release thermal stresses at two connecting edge positions continuously; and under the condition of bearing a temperature circulation loading, the cyclic thermal stresses between the ceramic substrate and the metal layers are reduced effectively, and the deformations at the edge positions in which a ceramic basic level is combined with the metal layers is reduced substantially, thereby solving the ceramic substrate cracking problem caused by the cracking at the edge positions in which the ceramic basic level is combined with the metal layers, and accordingly, improving the temperature circulation reliability and service life of the metal-clad ceramic substrate.

Description

Cover the cermet substrate

Technical field

The utility model relates to a kind of cermet substrate that covers, and belongs to technical field of semiconductors.

Technical background

What cover the cermet substrate is mainly used in the power electronic device industry; In a power model, several power semiconductor chips are arranged; Be integrated and be welded in or be glued on the metalized surface of covering the cermet substrate like MOSFET or igbt chip and diode chip for backlight unit, and the effect of ceramic substrate is when guaranteeing the good heat conductive performance, the electric insulation with respect to the module base plate to be provided also.Usually power electronic device need carry out work under-40 ℃ to 125 ℃ temperature cycles environment; Because the thermal coefficient of expansion of ceramic substrate and metal level can not mate; Can between ceramic substrate and metal level, produce cyclic thermal stres under the temperature cycles condition, especially two at the interface thermal stress be maximum, so cracking phenomena can appear in the jointing edge place of ceramic substrate and metal level; Thereby can cause the ceramic substrate cracking that covers in the cermet substrate, finally cause the inefficacy of covering the cermet substrate.Aluminium oxide ceramics copper-clad base plate commonly used at present is an example, and its life-span is approximately 300-500 temperature cycles number of times.Cause the power electronic device of untreated aluminium oxide copper-clad base plate encapsulation can not be used for the occasion higher to life requirements, like automotive electronics, the high power contravariant device in the fields such as solar energy, wind power generation.

Summary of the invention

The purpose of the utility model provides a kind ofly has efficiency ground to reduce the thermal cycling stresses that exists between ceramic layer and the metal level, improves the cermet substrate that covers the cermet substrate itself and the manufacture method in useful life.

The utility model is that the technical scheme that achieves the above object is: a kind of cermet substrate that covers; Base is characterised in that: comprise ceramic substrate and be laminated with the metal level at the ceramic substrate upper and lower surface; The outer peripheral face of metal level and the outer peripheral face of ceramic substrate have spacing d, and the outer peripheral face of metal level comprises the step surface of an attenuate annular at least.

The utility model forms the step surface of at least one attenuate annular in the periphery of two metal levels; Cover the thickness at metal level edge on the cermet substrate through attenuate; Make this step surface can constantly discharge the thermal stress at two adjoining edge places, under bearing temperature CYCLIC LOADING condition, can reduce the cyclic thermal stres between ceramic substrate and the metal level effectively; And reduce edge's deflection that ceramic basic unit is combining with metal level significantly; The cracking that has solved the edge's appearance that combines with metal level because of ceramic basic unit makes the problem of ceramic substrate cracking, so can significantly improve cermet substrate temperature circulation reliability and useful life, is example with aluminium oxide ceramics copper-clad base plate commonly used; Its life-span is about 600-800 temperature cycles, and the cermet substrate of the utility model can be applied in the high power device.

Description of drawings

Below in conjunction with accompanying drawing the embodiment of the utility model is made further detailed description.

Fig. 1 is the structural representation of the utility model cermet substrate.

Fig. 2 is the sectional structure sketch map of the A-A of Fig. 1.

Fig. 3 is the another kind of structural representation of the utility model.

Wherein: 1-ceramic substrate, 2-metal level, 3-step surface.

Embodiment

See shown in Fig. 1～3; The utility model cover the cermet substrate; Comprise ceramic substrate 1 and be laminated with the metal level 2 at ceramic substrate 1 upper and lower surface, ceramic substrate 1 can be one of them of aluminium oxide (Al203), aluminium nitride (AlN), bismuth oxide (Bi02), silicon nitride (Si3N4), carborundum (SiC), and metal level 2 then is copper layer or aluminium lamination or copper aluminium composite bed; With the upper and lower surface of metal level 2 direct weldings at ceramic substrate 1; Like the upper and lower surface of direct copper welding, or metal level 2 solderings are connected on the upper and lower surface of ceramic substrate 1, the metal level soldering are connected on the upper and lower surface of ceramic substrate 1 as adopting solder bonding metal initiatively at ceramic substrate 1; The outer peripheral face of the outer peripheral face of the utility model metal level 2 and ceramic substrate 1 has spacing d; The outer peripheral face of metal level 2 comprises the step surface 3 of an attenuate annular at least, and the step surface 3 of attenuate annular can adopt optical graving to get, and also in time the thermal stress between metal level edge and the ceramic basic unit is discharged better through step surface 3; And make the stress between metal level outward flange and the ceramic substrate can reach a metastable poised state, cover the instructions for use that the cermet substrate can satisfy power electronic device.

See shown in Fig. 1～3; The thickness H2 of the utility model metal level 2 is at 0.2～5mm; Spacing d between the outer peripheral face of the outer peripheral face of metal level 2 and ceramic substrate 1 is 1～5 times of ceramic substrate H1 thickness; Ceramic substrate thickness H1 is usually at 0.2～5mm; This spacing d can be 0.2mm, 0.4mm, 1mm, 5mm, 8mm, 10mm, 12mm, 15mm, 20mm, 22mm, 25mm etc.; Best spacing d is 2～3 times of ceramic substrate H1 thickness; The step thicknesses h of the step surface 3 of metal level 2 is that 1/10-1/2, the width B of metal layer thickness H2 is 1～5 times of metal layer thickness H2, is 0.02mm, 0.1mm, 0.4mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.6mm, 1.8mm, 2mm, 2.2mm, 2.5mm etc. like the step thicknesses h of step surface 3, and preferably step thicknesses h is the 1/5-1/3 of metal layer thickness H2; The width B of this step surface 3 is 0.2mm, 0.4mm, 1mm, 5mm, 8mm, 10mm, 12mm, 15mm, 20mm, 22mm, 25mm etc., and the width B of best step surface 3 is 2～3 times of metal layer thickness H2.

The step surface 3 of seeing metal level 2 peripheries of the utility model shown in Fig. 1～3 is two or three step surfaces; Step thicknesses h on each step surface 3 is identical; Or the step thicknesses h on each step surface 3 successively decreases from outside to ceramic substrate 1 one sides of metal level 2 successively, can be according to the thickness of metal level 2

Covering when die bonding on one of them metal level 2 of cermet substrate; 2 of another metal levels that cover the cermet substrate are connected with heating panel or radiator; With the good heat conduction of shape; Make the heat of power electronic device when work be passed to metal level 2, ceramic substrate 1 and another metal level 2 from chip, heat conducts on the thermal diffusion plate or radiator of bottom the most at last

Claims

1. one kind covers the cermet substrate; Base is characterised in that: comprise ceramic substrate (1) and be laminated with the metal level (2) at ceramic substrate (1) upper and lower surface; The outer peripheral face of the outer peripheral face of metal level (2) and ceramic substrate (1) has spacing d, and the outer peripheral face of metal level (2) comprises the step surface (3) of an attenuate annular at least.

2. the cermet substrate that covers according to claim 1; Base is characterised in that: the thickness H2 of said metal level (2) is at 0.2～5mm; Spacing d between the outer peripheral face of the outer peripheral face of metal level (2) and ceramic substrate (1) is 1～5 times of ceramic substrate H1 thickness, and the step thicknesses h of the step surface (3) of metal level (2) is that 1/10-1/2, the width B of metal layer thickness H2 is 1～5 times of metal layer thickness H2.

3. the cermet substrate that covers according to claim 2 is characterized in that: the step thicknesses h of the step surface (3) of said metal level (2) is that 1/5-1/3, the width B of metal layer thickness H2 is 2～3 times of metal layer thickness H2.

4. the cermet substrate that covers according to claim 1 and 2; It is characterized in that: the step surface (3) of said metal level (2) periphery is two or three step surfaces; Step thicknesses h on each step surface (3) is identical, or the step thicknesses h on each step surface (3) successively decreases from outside to ceramic substrate (1) one side of metal level (2) successively.