CN104046843A - Copper-nickel-silicon alloy material containing rare-earth cerium, lead frame strip and preparation method thereof - Google Patents

Abstract

The invention discloses a copper-nickel-silicon alloy material containing rare-earth cerium, a lead frame strip and a preparation method thereof. The alloy material is prepared from the following components in percentage by weight: 1.9-5.5% of Ni, 0.35-1.8% of Si, 0.001-0.02% of Ce, 0.01-0.12% of Ag, 0.01-0.12% of P, and the balance of Cu and inevitable impurities. The preparation method of the strip comprises the following steps: smelting and casting, hot rolling, on-line quenching (solid solution treatment), face milling, cold rolling, annealing (progressive aging treatment), stretch bending and straightening. The tensile strength of the obtained finished product is up to 700-900 Mpa, the electric conductivity is up to 48-78% IACS, the elongation percentage is not lower than 6%, and the softening temperature is not lower than 560 DEG C; and the finished product can well satisfy the performance requirements for copper alloy materials for large-scale integrated circuit lead frames.

Description

A kind of Corson alloy material that contains cerium, lead frame band and preparation method thereof

Technical field

The invention belongs to copper alloy technical field, relate generally to a kind of Corson alloy material that contains cerium, lead frame band and preparation method thereof.Be particularly useful for ultra-large and great scale integrated circuit blaster fuse frame material high strength high conductivity rare earth Corson alloy material, lead frame band and preparation method.

Background technology

Along with electronics and IT products are to miniaturization, slimming, lightweight and intelligent direction development and unicircuit (IC) to extensive (LSI) and great scale (GSI) future development, the performance requriements of lead frame Cu alloy material is also more and more high, and corresponding to short, light, thin, high strength, the researchdevelopment of high precision direction.

Extensive and great scale integrated circuit manufacture has complex manufacturing technology, operating frequency superelevation, service rating super large, the large outstanding feature of Working environment exceedingly odious four, therefore very harsh to the requirement of its mechanical property, conductivity, heat conductivility, high temperature softening resistant performance, corrosion resisting property.At present, global development Copper Alloys for Lead Frame out nearly more than 120 is planted, and main series is Cu-Fe-P system, Cu-Ni-Si system, Cu-Cr-Zr system.It is first-generation lead frame copper alloy that the Cu-Fe-P with medium tenacity is associated gold, there is good specific conductivity (being not less than 70%IACS), be the wider Albatra metal-of current circuit lead frame application, but the integrated performance indexs such as its tensile strength (being not more than 550MPa) and high temperature resistance softening temperature (being not more than 400 DEG C) also can not meet the requirement of great scale integrated circuit high loading long-term stable operation far away.Cu-Cr-Zr is associated gold utensil high strength, high conductivity and good heat-resistant stability, but Zr element is very easily oxidized, and such alloy quenching sensitive time prepared by band is strong, therefore its complex manufacturing, preparation cost are high, on market and for being widely used.

Cu-Ni-Si is associated gold utensil high tensile strength, good electrical and thermal conductivity performance, high anti-softening temperature, good corrosion resistance, is the ideal material of great scale integrated circuit.At present, China is associated gold at lead frame copper alloy with Cu-Ni-Si and is still in the experimental exploring stage, and its industrialization gordian technique urgently breaks through.High-strength Cu-Ni-Si series copper alloy is still all quite backward on producing in research, most of dependence on import.The existence that not only China's copper processing industry in serious threat of this situation, has also seriously hindered the development of the numerous high-technology fields of China.Therefore the Cu-Ni-Si used for lead frame that is necessary to provide that a kind of over-all properties is high, cost is low, production technique is simple, can industrialization produce is associated gold.

Summary of the invention

The object of the invention is to design a kind of Corson alloy material containing cerium with high strength, high conductivity, high temperature resistance softening temperature and excellent corrosion resistance, lead frame band and preparation method, meet demand extensive and great scale integrated circuit use lead frame band.

To achieve these goals, a kind of Corson alloy material that contains cerium is proposed according to the present invention, this alloy material is made up of the component of following weight percent: 1.9～5.5% nickel, 0.35～1.8% silicon, 0.001～0.02% rare-earth element cerium, 0.01～0.12% silver, 0.01～0.12% phosphorus, surplus is copper.Can also comprise inevitable impurity.

Preferred version of the present invention is: 2.2～4.2% nickel, and 0.4～1.2% silicon, 0.001～0.01% rare-earth element cerium, 0.01～0.08% silver, 0.01～0.08% phosphorus, surplus is copper.Can also comprise inevitable impurity.

The further preferred version of the present invention is: 3.2～3.8% nickel, and 0.7～0.95% silicon, 0.005～0.008% rare-earth element cerium, 0.04～0.06% silver, 0.04～0.06% phosphorus, surplus is copper.Can also comprise inevitable impurity.

Preferably, described nickel: silicon=3.5～5.5.Preferably nickel: silicon=4.0～4.6.

The present invention also provides a kind of lead frame band that adopts the above-mentioned Corson alloy material that contains cerium to prepare.

The present invention provides a kind of preparation method of lead frame band in addition, and step is melting and casting → hot rolling-press quenching → milling face → cold rolling → annealing → stretch-bending straightening.Specifically comprise the steps:

1) melting and casting: electrolytic copper and electrolytic nickel are required to drop into smelting furnace according to above-mentioned mass percent, add successively until completely melted silver, phosphorus, silicon and copper cerium master alloy, smelting temperature is 1180～1280 DEG C;

2) hot rolling-press quenching: the Corson alloy that contains cerium of 840～940 DEG C is carried out to hot rolling on milling train, and press quenching, finishing temperature is not less than 680 DEG C;

3) milling face: by strip surface zone of oxidation and mass defect milling, milling depth: one side milling amount: 0.25～0.85mm, monolateral milling amount: 2-10mm;

4) cold rolling: by milling train, strip-rolling to be become to meet the strip that product size requires;

5) annealing: the band after rolling is carried out to interrupted aging processing, and aging temp is controlled at 380～520 DEG C, soaking time 1.5～8h.Meanwhile, need alloy to carry out three times and three above ageing treatment according to over-all properties;

6) stretch-bending straightening: band is carried out on straightener to stretch-bending straightening processing, the flatness defect of conditioning strip material and the inner unrelieved stress of minimizing.

What the present invention proposed is a kind of Corson alloy material that contains cerium, and it has high strength, high conductivity, high temperature resistance softening temperature and excellent corrosion resistance.The Ni that this alloy adds, the second-phase Ni that Si separates out generation ₂si produces strengthening effect, adopts suitable proportioning to ensure that alloy is after timeliness, and residual less alloying element in copper matrix, makes alloy obtain performance relatively preferably; The rare-earth element cerium adding hardly solid solution in copper, effect in copper is rotten and purifies, can deoxidation, and can form high melting compound with low melting point impurity, eliminate deleterious effect, improve the plasticity of copper alloy, can improve plasticity, reduce cold worked crackle, determine that its addition is in 0.001～0.01% scope; The silver adding, electric conductivity on copper, thermal conductivity impact are little, and can significantly improve recrystallization temperature, creep-resistant property and wear resisting property, determine that its addition is in 0.01～0.08% scope; The phosphorus adding is the reductor the most effective, cost is minimum, the existence of trace amounts of phosphorus, can improve the mobility of melt, improve the anti-softening temperature of welding property, corrosion resisting property, raising of copper alloy, the phosphorus of solid solution in copper significantly reduces its electroconductibility, phosphorous 0.014% soft band electric conductivity is 94%IACS, and phosphorous 0.14% electric conductivity is only 45.2%, therefore determines that its addition is in 0.01～0.08% scope.

The tensile strength of the Corson alloy material gained finished product under above-mentioned technique that contains cerium of the present invention reaches 700～900Mpa, specific conductivity and reaches that 48～78%IACS, unit elongation are not less than 6%, softening temperature is not less than 560 DEG C, can meet preferably the performance requirement of large-scale integrated circuit lead frame Cu alloy material.

Additional aspect of the present invention and advantage in the following description part provide, and part will become obviously from the following description, or recognize by practice of the present invention.

Embodiment

With reference to specification sheets to a kind of Corson alloy material that contains cerium of the present invention, lead frame band and preparation method be described in detail below.

Embodiment of the present invention 1-4 design is a kind of have high strength, high conductivity, high temperature resistance softening temperature and excellent corrosion resistance the Corson alloy material containing cerium, lead frame band and preparation method, meet extensive and great scale integrated circuit and use the demand of lead frame band.This alloy is by making forming of following weight percent: 3.2～3.8% nickel, and 0.7～0.95% silicon, 0.005～0.008% rare-earth element cerium, 0.04～0.06% silver, 0.04～0.06% phosphorus, surplus is copper.Can also comprise inevitable impurity.Described nickel: silicon=3.5～5.5.Preferably nickel: silicon=4.0～4.6.Concrete amounts of components is in table 1.

The preparation method that the present invention realizes lead frame band prepared by the above-mentioned Corson alloy material that contains cerium mainly comprises the steps:

(1) melting and casting: electrolytic copper and electrolytic nickel are required to drop into smelting furnace according to above-mentioned mass percent, add successively until completely melted silver, phosphorus, silicon and copper cerium master alloy, smelting temperature is 1230 DEG C;

(2) hot rolling-press quenching: the Corson alloy that contains cerium of 860 DEG C is carried out to hot rolling on milling train, and press quenching, finishing temperature is 690 DEG C;

(3) milling face: by strip surface zone of oxidation and mass defect milling, milling depth: one side milling amount: 0.5mm, monolateral milling amount: 6mm;

(4) cold rolling: the strip that by milling train, strip-rolling is become to 0.1mm;

(5) annealing: the band after rolling is carried out to interrupted aging processing, and aging temp is controlled at 450 DEG C, soaking time 3h.Meanwhile, need alloy to carry out three times and three above ageing treatment according to over-all properties;

(6) stretch-bending straightening: band is carried out on straightener to stretch-bending straightening processing, the flatness defect of conditioning strip material and the inner unrelieved stress of minimizing.

Composition and performance in each specific embodiment are shown in Table 1:

Table 1:

?	Example 1	Example 2	Example 3	Example 4
					Cu％	Surplus	Surplus	Surplus	Surplus
Ni％	3.2	3.2	3.8	3.8
					Si％	0.7	0.8	0.85	0.95
Ce％	0.005	0.008	0.005	0.008
					Ag％	0.04	0.06	0.04	0.06
P％	0.04	0.06	0.04	0.06

Tensile strength Mpa	864	732	887	768
					Specific conductivity %IACS	72	67	75	64
Unit elongation %	5.2	5.3	6	5.8
					Anti-softening temperature degree DEG C	567	573	592	581
Erosion rate g/m 2·h	0.0869	0.0761	0.0683	0.0812

By above example, the ratio of Ni and Si is 4.5.Within the specific limits, its over-all properties is more excellent for rare-earth element cerium, silver, phosphorus.Preferred embodiment of the present invention is 3.

Corrosion resisting property testing method is as follows:

Sample is cut into the square of 10 × 10mm with line, carries out again polishing with after sand papering, allow matrix of samples expose, wash away the surperficial oxide compound of sample with 10% dilute sulphuric acid, water rinses then dry, weighs, and calculate the surface-area of sample after being dried with electronic balance.(3.5%) aqueous solution of NaCl for corrosive fluid and H ₂sO ₄solution allocation forms, and pH is in 5 left and right.In this test, with fine rule, test materials being suspended in the beaker that fills corrosive fluid, in order to make corrosion more complete, is that material is immersed in corrosive fluid completely, does not contact with the wall of cup of beaker, and this test period is 15 days.

The size of metallic corrosion degree adopts weight-loss method to evaluate, and calculation formula is as follows:

$v=\frac{\mathrm{Ma}-\mathrm{Mb}}{s\·h}$

Wherein, V: erosion rate, the g/m of unit ²h;

S: the surface-area that sample is total, unit 10 ^-4m ²;

H: etching time, the h of unit;

M a: the weight before corrosion, the g of unit;

M b: the weight after corrosion, the g of unit.

Although illustrated and described embodiments of the invention, those having ordinary skill in the art will appreciate that: in the situation that not departing from principle of the present invention and aim, can carry out multiple variation, amendment, replacement and modification to these embodiment, scope of the present invention is limited by claim and equivalent thereof.

Claims (7)

1. a Corson alloy material that contains cerium, it is characterized in that, this alloy material is made up of the component of following weight percent: 1.9～5.5% nickel, 0.35～1.8% silicon, 0.001～0.02% rare-earth element cerium, 0.01～0.12% silver, 0.01～0.12% phosphorus, surplus is copper and inevitable impurity.

2. the Corson alloy material that contains cerium according to claim 1, it is characterized in that, its component is: 2.2～4.2% nickel, 0.4～1.2% silicon, 0.001～0.01% rare-earth element cerium, the silver of Ag0.01～0.08%, the phosphorus of P0.01～0.08%, surplus is copper and inevitable impurity.

3. the Corson alloy material that contains cerium according to claim 1, it is characterized in that, its component is: 3.2～3.8% nickel, 0.7～0.95% silicon, 0.005～0.008% rare-earth element cerium, 0.04～0.06% silver, 0.04～0.06% phosphorus, surplus is copper and inevitable impurity.

4. the Corson alloy material that contains cerium according to claim 1, is characterized in that described nickel: silicon=3.5～5.5.

5. the Corson alloy material that contains cerium according to claim 4, is characterized in that described nickel: silicon=4.0～4.6.

6. a lead frame band that adopts the Corson alloy material that contains cerium described in claim 1-5 any one to prepare.

7. a preparation method for lead frame band as claimed in claim 6, is characterized in that, comprises the steps:

1) melting and casting: alloy is required according to mass percent and certain order input smelting furnace, smelting temperature is 1180～1280 DEG C;

2) hot rolling-press quenching: the Corson alloy that contains cerium of 840～940 DEG C is carried out to hot rolling on milling train, and press quenching, finishing temperature is not less than 680 DEG C;

3) milling face: by strip surface zone of oxidation and mass defect milling, milling depth: one side milling amount: 0.25～0.85mm, monolateral milling amount: 2-10mm;

4) cold rolling: by milling train, strip-rolling to be become to meet the strip that product size requires;

5) annealing: the band after rolling is carried out to interrupted aging processing, and aging temp is controlled at 380～520 DEG C, soaking time 1.5～8h, meanwhile, needs alloy to carry out three times and three above ageing treatment according to over-all properties;

6) stretch-bending straightening: band is carried out on straightener to stretch-bending straightening processing, the flatness defect of conditioning strip material and the inner unrelieved stress of minimizing.