Preparation method of ceramic metal composite cover plate with good thermal shock resistance

Abstract

The invention discloses a preparation method of a ceramic metal composite cover plate with good thermal shock resistance. The invention discloses a preparation method of a ceramic metal composite cover plate with good thermal shock resistance. The preparation method comprises the following steps: step 1, cleaning a ceramic wafer; step 2, double-sided oxidation of the copper foil; step 3, stacking; stacking the ceramic chips, the copper foils and the ceramic chips from bottom to top in sequence; and 4, sintering. The invention provides a composite cover plate structure. A sandwich structure of a ceramic chip, a copper foil and a ceramic chip is adopted to replace an original single ceramic cover plate.

Description

Technical Field

[0001] The invention relates to the technical field of sintering, and in particular to a method for preparing a cover plate. Background Art

[0002] When the DCB substrate is sintered in the sintering furnace, a ceramic cover plate (usually made of 96% alumina) is used. The cover plate can change the starting point of the copper foil and ceramic combination during product sintering or prevent the metal oxide on the furnace wall from falling directly onto the cover plate when it falls off, so as to improve the sintering yield. However, the ceramic cover plate is very easy to crack during the heating and cooling process, which not only causes the loss of the ceramic plate itself, but also causes the DCB product to be scrapped. In severe cases, the cracked fragments may even block the furnace, causing more product scrapping and waste of production capacity. There is currently no effective way to avoid this situation, and it needs to be solved urgently. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention provides a method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, which solves at least one of the above technical problems.

[0004] The technical solution of the present invention is: a method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, characterized in that it comprises the following steps:

[0005] Step 1, cleaning the ceramic sheet;

[0006] Step 2: Double-sided oxidation of copper foil;

[0007] Step 3: stacking: stacking from bottom to top according to the order of ceramic sheet, copper foil and ceramic sheet;

[0008] Step 4: sintering.

[0009] The present invention provides a composite cover plate structure, which significantly reduces the loss of ceramic cover plates and has significant economic benefits.

[0010] Further preferably, the copper foil is made of high-purity oxygen-free copper with a purity of more than 99.99%.

[0011] Further preferably, the size of the copper foil is 132*184*0.127 or 132*184*0.2 mm.

[0012] Further preferably, the ceramic sheet is made of 96% alumina.

[0013] Further preferably, the size of the ceramic sheet is 160*200*(0.32-0.5) mm.

[0014] Further preferably, in step 2, the copper foil is oxidized on both sides in a nitrogen-oxygen mixed gas with an oxygen content of 100-1000 ppm, the oxidation temperature is 400-800° C., and the oxidation speed is 50-300 mm / min.

[0015] Further preferably, in step 4, the sintering temperature is controlled at 1065° C.-1083° C., nitrogen atmosphere, and mesh belt speed is 50-200 mm / min.

[0016] A method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, characterized in that it comprises the following steps:

[0017] Step 1, cleaning the ceramic sheet; the ceramic sheet is made of 96% alumina; the size of the ceramic sheet is 160*200*(0.32-0.5) mm;

[0018] Step 2: Double-sided oxidation of copper foil; the copper foil is made of high-purity oxygen-free copper with a purity of more than 99.99%;

[0019] The size of the copper foil is 132*184*0.127 or 132*184*0.2mm;

[0020] The copper foil is oxidized on both sides in a nitrogen-oxygen mixed gas with an oxygen content of 100-1000ppm, the oxidation temperature is 400-800℃, and the oxidation speed is 50-300mm / min;

[0021] Step 3: stacking: stacking from bottom to top according to the order of ceramic sheet, copper foil and ceramic sheet;

[0022] Step 4: sintering;

[0023] The sintering temperature is controlled at 1065°C-1083°C, nitrogen atmosphere, and mesh belt speed is 50-200mm / min.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention provides a composite cover plate structure. The loss of ceramic cover plates is significantly reduced, and significant economic benefits are achieved. A "sandwich" structure of ceramic sheet + copper foil + ceramic sheet is used to replace the original single ceramic cover plate. The copper foil and ceramic are bonded together at high temperature through DCB technology, and the good ductility and plasticity of metal are used to improve the brittleness and poor thermal shock resistance of ceramics, thereby reducing the loss of the cover plate itself and also reducing the scrapping of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of specific embodiment 1 of the present invention. DETAILED DESCRIPTION

[0027] See also Figure 1 , Specific embodiment 1, a method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, comprising the following steps:

[0028] Step 1, cleaning the ceramic sheet;

[0029] Step 2: Double-sided oxidation of copper foil;

[0030] Step 3: stacking: stacking from bottom to top according to the order of ceramic sheet, copper foil and ceramic sheet;

[0031] Step 4: sintering.

[0032] The present invention provides a composite cover plate structure, which significantly reduces the loss of ceramic cover plates and has significant economic benefits.

[0033] The copper foil is made of high-purity oxygen-free copper with a purity of more than 99.99%. The size of the copper foil is 132*184*0.127 or 132*184*0.2 mm.

[0034] The ceramic sheet is made of 96% alumina.

[0035] The size of the ceramic sheet is 160*200*(0.32-0.5) mm.

[0036] In step 2, the copper foil is oxidized on both sides in a nitrogen-oxygen mixed gas with an oxygen content of 100-1000 ppm, the oxidation temperature is 400-800° C., and the oxidation speed is 50-300 mm / min.

[0037] In step 4, the sintering temperature is controlled at 1065° C.-1083° C., nitrogen atmosphere, and mesh belt speed is 50-200 mm / min.

[0038] A method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, characterized in that it comprises the following steps:

[0039] Step 1, cleaning the ceramic sheet; the ceramic sheet is made of 96% alumina; the size of the ceramic sheet is 160*200*(0.32-0.5) mm;

[0040] Step 2: Double-sided oxidation of copper foil; the copper foil is made of high-purity oxygen-free copper with a purity of more than 99.99%;

[0041] The size of the copper foil is 132*184*0.127 or 132*184*0.2mm;

[0042] The copper foil is oxidized on both sides in a nitrogen-oxygen mixed gas with an oxygen content of 100-1000ppm, the oxidation temperature is 400-800℃, and the oxidation speed is 50-300mm / min;

[0043] Step 3: stacking: stacking from bottom to top according to the order of ceramic sheet, copper foil and ceramic sheet;

[0044] Step 4: sintering;

[0045] The sintering temperature is controlled at 1065°C-1083°C, nitrogen atmosphere, and mesh belt speed is 50-200mm / min.

[0046] Comparison between the present invention and the original ceramic cover plate:

[0047] type Number of scrapped cover sheets / day / machine Original ceramic cover 15-30 The present invention (ceramic-metal composite cover plate) 0-2

[0048] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, characterized in that: The steps include: Step 1, cleaning the ceramic sheet; Step 2: Double-sided oxidation of copper foil; Step 3: stacking: stacking from bottom to top according to the order of ceramic sheet, copper foil and ceramic sheet; Step 4: sintering.

2. The method for preparing a ceramic-metal composite cover plate with good thermal shock resistance according to claim 1, characterized in that: The copper foil is made of high-purity oxygen-free copper with a purity of more than 99.99%.

3. The method for preparing a ceramic-metal composite cover plate with good thermal shock resistance according to claim 1, characterized in that: The size of the copper foil is 132*184*0.127 or 132*184*0.2 mm.

4. The method for preparing a ceramic-metal composite cover plate with good thermal shock resistance according to claim 1, characterized in that: The ceramic sheet is made of 96% alumina.

5. The method for preparing a ceramic-metal composite cover plate with good thermal shock resistance according to claim 1, characterized in that: The size of the ceramic sheet is 160*200*(0.32-0.5) mm.

6. The method for preparing a ceramic-metal composite cover plate with good thermal shock resistance according to claim 1, characterized in that: In step 2, the copper foil is oxidized on both sides in a nitrogen-oxygen mixed gas with an oxygen content of 100-1000 ppm, the oxidation temperature is 400-800° C., and the oxidation speed is 50-300 mm / min.

7. The method for preparing a ceramic-metal composite cover plate with good thermal shock resistance according to claim 1, characterized in that: In step 4, the sintering temperature is controlled at 1065° C.-1083° C., nitrogen atmosphere, and mesh belt speed is 50-200 mm / min.

8. A method for preparing a ceramic-metal composite cover plate with good thermal shock resistance, characterized in that: The steps include: Step 1, cleaning the ceramic sheet; the ceramic sheet is made of 96% alumina; the size of the ceramic sheet is 160*200*(0.32-0.5) mm; Step 2: Double-sided oxidation of copper foil; the copper foil is made of high-purity oxygen-free copper with a purity of more than 99.99%; The size of the copper foil is 132*184*0.127 or 132*184*0.2mm; The copper foil is oxidized on both sides in a nitrogen-oxygen mixed gas with an oxygen content of 100-1000ppm, the oxidation temperature is 400-800℃, and the oxidation speed is 50-300mm / min; Step 3: stacking: stacking from bottom to top according to the order of ceramic sheet, copper foil and ceramic sheet; Step 4: sintering; The sintering temperature is controlled at 1065°C-1083°C, nitrogen atmosphere, and mesh belt speed is 50-200mm / min.

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