阅读说明：本技术 一种集成电路用高强高导高韧铜钛合金及其制备方法 (High-strength, high-conductivity and high-toughness copper-titanium alloy for integrated circuit and preparation method thereof ) 是由 晏弘 于 2020-12-23 设计创作，主要内容包括：本发明公开了一种集成电路用高强高导高韧铜钛合金,所述铜钛合金所含元素及各元素的重量百分比为：钛2.9-3.4％、铁0.17-0.23％、铝0.15-0.20％、硼0.03-0.10％,余量为铜和不可避免的杂质；所述高强高导高韧铜钛合金的制备方法,包括如下步骤：(1)配料；(2)真空熔炼,形成铜钛合金熔体；(3)浇铸,形成铸锭；(4)冷轧,获得板材；(5)时效处理。本发明合金具有强度高、导电性好、韧性强的优势,主要用于集成电路,特别是大规模和超大规模集成电路框架以及各种电子产品接插件。(The invention discloses a high-strength, high-conductivity and high-toughness copper-titanium alloy for an integrated circuit, which comprises the following elements in percentage by weight: 2.9 to 3.4 percent of titanium, 0.17 to 0.23 percent of iron, 0.15 to 0.20 percent of aluminum, 0.03 to 0.10 percent of boron, and the balance of copper and inevitable impurities; the preparation method of the high-strength, high-conductivity and high-toughness copper-titanium alloy comprises the following steps: (1) preparing materials; (2) vacuum melting to form a copper-titanium alloy melt; (3) casting to form a cast ingot; (4) cold rolling to obtain a plate; (5) and (5) aging treatment. The alloy has the advantages of high strength, good conductivity and strong toughness, and is mainly used for integrated circuits, in particular large-scale and ultra-large-scale integrated circuit frames and various electronic product connectors.)

1. The high-strength, high-conductivity and high-toughness copper-titanium alloy for the integrated circuit is characterized by comprising the following elements in percentage by weight: 2.9 to 3.4 percent of titanium, 0.17 to 0.23 percent of iron, 0.15 to 0.20 percent of aluminum, 0.03 to 0.10 percent of boron, and the balance of copper and inevitable impurities.

2. The high strength, high conductivity and high toughness copper titanium alloy according to claim 1, wherein titanium is electrolyzed to provide Ti element; electrolytic iron which provides an Fe element; electrolyzing aluminum to provide Al element; elemental boron, providing element B; TU2 contains oxygen free copper, providing the Cu element.

3. The preparation method of the high-strength, high-conductivity and high-toughness copper-titanium alloy according to claim 1, wherein the preparation method comprises the following steps:

(1) preparing materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 2.9 to 3.4 percent of titanium, 0.17 to 0.23 percent of iron, 0.15 to 0.20 percent of aluminum, 0.03 to 0.10 percent of boron, and the balance of copper and inevitable impurities;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into vacuum smelting equipment, and carrying out vacuum smelting to form a copper-titanium alloy melt;

(3) casting: casting the copper alloy titanium melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water;

(4) cold rolling: cold-rolling the slab ingot obtained in the step (3) into a plate with the thickness of 0.2-0.4 mm;

(5) aging treatment: and (4) ageing the plate obtained in the step (4) at the temperature of 350-450 ℃ for 5-15 hours.

4. The production method according to claim 3, wherein in the step (2), the vacuum melting apparatus is a vacuum induction furnace.

5. The production method according to claim 3, wherein in the step (3), the vacuum melting conditions are as follows: the vacuum degree is 10-10^-2Pa, the temperature is 1200-1500 ℃, and the temperature is kept for 20-30 min.

Technical Field

The invention relates to the technical field of metal materials, in particular to a high-strength, high-conductivity and high-toughness copper-titanium alloy for an integrated circuit and a preparation method thereof.

Background

Lead frame materials for integrated circuits and semiconductors at home and abroad are classified into two major types, iron-nickel alloy (Fe42Ni) and copper alloy. The iron-nickel alloy has high strength and softening temperature, but low electric conductivity and thermal conductivity, and is mainly used for ceramic and glass packaging. Copper alloy lead frames have been consumed in 90% of the total amount since the twenty-first century because of its excellent electrical conductivity and low cost.

In addition to high strength and high conductivity, copper alloys used for lead frames, various terminals of electronic devices, connectors, and the like are required to have high density packaging and high reliability, and electronic components are required to have a high density of packaging due to the rapid progress of the reduction in pitch by increasing the number of leads on connectors for various terminals. Therefore, a material used for electronic parts is also required to have excellent workability.

Of these alloys, the CuTi age-hardening type alloys are representative, with Ti addition levels generally most preferably in the range of 3.0% to 4.5% by weight. For example: cu-3.5Ti alloy, Cu-3.5Ti-0.2Cr alloy, Cu-6Ti-1Al alloy, etc. Typical processes for these alloys are generally: the processing technology of ingot casting, hot rolling, solution treatment, cold rolling and aging treatment is relatively complex, and the performance of the product is directly influenced by the quality of the processing technology.

In order to improve the performance of the product, a number of patents propose methods of adding different trace elements: for example, more than 0.35 wt% of Sn is added on the CuTi alloy matrix to strengthen the alloy, wherein the Cu-1.6% wtTi-2.5% wtSn alloy has the best precipitation strengthening effect; 0.5-0.7 wt% of Fe is added into the Cu-4.0 wt% of Ti alloy, so that the plasticity and the wear resistance of the alloy can be improved; adding Ni element such as Cu-0.58 wt% Ti-2.06 wt% Ni on CuTi alloy matrix can realize obvious precipitation hardening effect; adding at least one of the following elements into the CuTi alloy matrix: 0.01-0.5 wt% (Cr, V, Zr, B, P) of the rare earth metal oxide can delay the growth of crystal grains in the recrystallization annealing process; 0.3-1.0 wt% of Zn is added into the CuTi alloy matrix, so that the castability of the alloy can be improved; 0.1-0.5 wt% of Mg is added into the CuTi alloy matrix, so that the stress relaxation resistance of the alloy can be improved. Although the addition of these trace elements improves the properties of gold to some extent, the addition of these trace elements is not enough to make the properties of the alloy leap forward without changing the processing technology of the alloy, and cannot reach a sufficient degree in terms of strength, conductivity and toughness.

Disclosure of Invention

In view of the above problems in the prior art, the applicant of the present invention provides a high strength, high conductivity and high toughness copper-titanium alloy for integrated circuits and a preparation method thereof. The alloy has the advantages of high strength, good conductivity and strong toughness, and is mainly used for integrated circuits, in particular large-scale and ultra-large-scale integrated circuit frames and various electronic product connectors.

The technical scheme of the invention is as follows:

the high-strength, high-conductivity and high-toughness copper-titanium alloy for the integrated circuit comprises the following elements in percentage by weight: 2.9 to 3.4 percent of titanium, 0.17 to 0.23 percent of iron, 0.15 to 0.20 percent of aluminum, 0.03 to 0.10 percent of boron, and the balance of copper and inevitable impurities.

Electrolytic titanium which provides Ti element; electrolytic iron which provides an Fe element; electrolyzing aluminum to provide Al element; elemental boron, providing element B; TU2 contains oxygen free copper, providing the Cu element.

A preparation method of the high-strength, high-conductivity and high-toughness copper-titanium alloy comprises the following steps:

(1) preparing materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 2.9 to 3.4 percent of titanium, 0.17 to 0.23 percent of iron, 0.15 to 0.20 percent of aluminum, 0.03 to 0.10 percent of boron, and the balance of copper and inevitable impurities;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into vacuum smelting equipment, and carrying out vacuum smelting to form a copper-titanium alloy melt;

(3) casting: casting the copper-titanium alloy melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water to achieve the purpose of solution treatment;

(4) cold rolling: cold-rolling the slab ingot obtained in the step (3) into a plate with the thickness of 0.2-0.4 mm;

(5) aging treatment: and (4) ageing the plate obtained in the step (4) at the temperature of 350-450 ℃ for 5-15 hours.

In the step (2), the vacuum smelting equipment is a vacuum induction furnace.

In the step (3), the vacuum melting conditions are as follows: the vacuum degree is 10-10^-2Pa, the temperature is 1200-1500 ℃, and the temperature is kept for 20-30 min.

The beneficial technical effects of the invention are as follows:

the invention adds a trace amount of Fe, Al and B elements on a CuTi alloy matrix. Fe acts in the alloy as: fe element is easy to form intermetallic compound with Ti, and ultrafine high-melting-point compound particles are suspended in the melt to form dispersed crystalline core, so that the crystalline grains become more and smaller, thereby refining the crystalline grains and improving the wear resistance of the alloy; because the atomic radius of iron is smaller than that of copper, the surface defect of a new phase of crystal grains in the growth process of copper or copper alloy is easily filled, and a film which can prevent the crystal grains from continuously growing is generated, thereby playing the role of refining the crystal grains. Meanwhile, Fe can reduce the hardness of the Cu-Ti alloy after solution treatment, improve the plasticity, obviously prevent the crystal grains from growing during heating and inhibit the crystal boundary reaction in the aging process; the Al plays a role in the alloy: in the aging process, Al element and the matrix form AlCu2Ti phase, thereby reducing the Ti atom content in the matrix and greatly improving the conductivity of the alloy; b has the following functions in the alloy: the B element positioned at the grain boundary inhibits the discontinuous precipitation of beta-Cu 4Ti at the grain boundary, thereby reducing the possibility of the initiation and the propagation of intergranular cracks of the alloy and improving the ductility and the hardness of the alloy on the premise of not influencing the electrical conductivity. The addition of the trace elements can greatly improve the overall performance of the copper-titanium alloy, so that the copper-titanium alloy has high strength, good conductivity and toughness.

The alloy composition of the invention is reasonable, the prepared copper alloy has the advantages of high strength, good conductivity, strong toughness and the like, and the copper alloy can be used for integrated circuits, in particular large-scale and ultra-large-scale integrated circuit frames and various electronic product connectors. The preparation method of the copper alloy eliminates the hot rolling procedure, so that the processing procedure is simpler.

Detailed Description

The present invention will be described in detail with reference to examples.

Example 1

A preparation method of a high-strength, high-conductivity and high-toughness copper-titanium alloy comprises the following steps:

(1) preparing materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 3.0% of titanium, 0.18% of iron, 0.16% of aluminum, 0.05% of boron, and the balance of copper and inevitable impurities; electrolytic titanium which provides Ti element; electrolytic iron which provides an Fe element; electrolyzing aluminum to provide Al element; elemental boron, providing element B; TU2 oxygen free copper, providing Cu element;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into vacuum melting equipment for vacuum melting, wherein the vacuum degree is 0.5Pa, and the temperature is 1250 ℃ and is kept for 25min to form a copper-titanium alloy melt;

(3) casting: casting the copper-titanium alloy melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water to achieve the purpose of solution treatment; obtaining an ingot with the thickness of 40mm and the width of 105 mm;

(4) cold rolling: cold-rolling the cast ingot obtained in the step (3) into a plate with the thickness of 0.3 mm;

(5) aging treatment: and (4) ageing the plate obtained in the step (4) at the temperature of 400 ℃ for 10 hours to obtain the copper-titanium alloy. The results of the performance tests are shown in table 1.

Example 2

A preparation method of a high-strength, high-conductivity and high-toughness copper-titanium alloy comprises the following steps:

(1) preparing materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 3.2% of titanium, 0.2% of iron, 0.18% of aluminum, 0.07% of boron, and the balance of copper and inevitable impurities; electrolytic titanium which provides Ti element; electrolytic iron which provides an Fe element; electrolyzing aluminum to provide Al element; elemental boron, providing element B; TU2 oxygen free copper, providing Cu element;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into vacuum melting equipment for vacuum melting, wherein the vacuum degree is 10Pa, and the temperature is 1250 ℃ and is kept for 30min to form a copper-titanium alloy melt;

(3) casting: casting the copper-titanium alloy melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water to achieve the purpose of solution treatment; obtaining an ingot with the thickness of 40mm and the width of 105 mm;

(4) cold rolling: cold-rolling the cast ingot obtained in the step (3) into a plate with the thickness of 0.3 mm;

(5) aging treatment: and (4) aging the plate obtained in the step (4) at the temperature of 420 ℃ for 8 hours to obtain the copper-titanium alloy. The results of the performance tests are shown in table 1.

Example 3

A preparation method of a high-strength, high-conductivity and high-toughness copper-titanium alloy comprises the following steps:

(1) preparing materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 3.4% of titanium, 0.22% of iron, 0.20% of aluminum, 0.09% of boron, and the balance of copper and inevitable impurities; electrolytic titanium which provides Ti element; electrolytic iron which provides an Fe element; electrolyzing aluminum to provide Al element; elemental boron, providing element B; TU2 oxygen free copper, providing Cu element;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into vacuum melting equipment for vacuum melting, keeping the vacuum degree at 0.01Pa and the temperature at 1350 ℃ for 20min to form a copper-titanium alloy melt;

(3) casting: casting the copper-titanium alloy melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water to achieve the purpose of solution treatment; obtaining an ingot with the thickness of 40mm and the width of 105 mm;

(4) cold rolling: cold-rolling the cast ingot obtained in the step (3) into a plate with the thickness of 0.2 mm;

(5) aging treatment: and (4) aging the plate obtained in the step (4) at the temperature of 450 ℃ for 8 hours to obtain the copper-titanium alloy. The results of the performance tests are shown in table 1.

TABLE 1

As can be seen from Table 1, the properties of the copper-titanium alloys obtained in examples 1 to 3, compared with the existing C70250 copper alloy, have achieved the strength and conductivity of the C70250 copper alloy, and in terms of the processing technique, hot rolling and solution treatment are eliminated, so that the processing technique is simpler and more convenient.