JPS6338414B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a Cu alloy lead material used in the manufacture of semiconductor devices such as ICs and LSIs. [Prior Art] In general, Cu alloy lead materials used as lead materials for semiconductor devices have the following properties: (1) Good press punching properties; (2) Heat distortion and heat softening occur during heat bonding or heat diffusion compression bonding of semiconductor elements. (3) Good heat dissipation and conductivity; (4) Strength and elongation that will prevent damage from bending or repeated bending when transporting semiconductor devices or incorporating them into electrical equipment. In terms of specific fields of use, for the purpose of evaluating strength, tensile strength: 40Kgf/
mm ² or more, elongation: 4% or more, conductivity: 50% IACS or more, for the purpose of evaluating heat dissipation and conductivity, softening point: 400℃ or more, for the purpose of evaluating heat resistance,
However, many Cu alloy lead materials having these characteristics have been proposed and put into practical use. [Problems to be solved by the invention] However, with the increasing degree of integration of semiconductor devices in recent years, Cu alloy lead materials have
In addition to having the above characteristics, higher strength and higher elongation are now required, and there is a strong desire to develop a Cu alloy lead material that has characteristics that can fully meet these requirements. [Means for Solving the Problems] Therefore, from the above-mentioned viewpoint, the present inventors have developed a Cu alloy lead material with even higher strength and elongation, in addition to having the characteristics required for a Cu alloy lead material for semiconductor devices. As a result of conducting research to develop a Cu alloy lead material with Contains one or two of C: 5 to 60 ppm, and further contains one or more of Ni, Sn, Fe, Co, and Be (hereinafter referred to as Group 1 metals). ): 0.005 to 2%, one or more of Mg, Si, Al, Zn, Mn, B, P, Li, Y, and rare earth elements (hereinafter referred to as Group 2 metals): 0.001 ~1%, one or more of Ti, Nb, V, Ta, Hf, Mo, and W (hereinafter referred to as Group 3 metals): 0.005 to 2%, Groups 1 to 3 Contains one or more of the following metals, with the remainder consisting of Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less). , which generally refers to component metals that appear during the solidification process from a molten alloy (here mainly composed of Cr), has an average particle size of 20 to 100 μm, but is generally 10 μm or less, and precipitates (precipitates) The term "compound" generally refers to a component metal that emerges from a solid solution through heat treatment, etc. (here, it mainly consists of Cu ₃ Cr and Cr), which also has an average particle size of 0.5 to 3 μm.
The lead material is made of a Cu alloy with a grain size of 0.1 μm or less, and an average grain size of 50 μm or less instead of the normal average grain size of 60 to 200 μm. Tensile strength: 52 Kgf/mm ² or more, elongation : 6.2% or more, electrical conductivity: 53% IACS or more, softening point: 410°C or more, and Cu alloy lead materials with these characteristics are fully satisfactory as lead materials for highly integrated semiconductor devices. We have gained knowledge that it can perform well. This invention was made based on the above knowledge, and the reason why the component composition was limited as described above will be explained below. (a) Cr and Zr These components have the effect of improving strength and heat resistance, but the content of each
If Cr: less than 0.05% and Zr: less than 0.005%, the desired effect cannot be obtained, while if the content exceeds Cr: 1% and Zr: 0.3%, nonmetallic inclusions are likely to occur. As the plating properties and conductivity deteriorate,
Its content is Cr: 0.05~1%, Zr: 0.005~0.3
%. (b) C The C component forms carbides, contributes to the refinement of crystal grains and precipitates, and has the effect of improving strength, but if its content is less than 5 ppm, the desired high strength cannot be achieved. On the other hand, if the content exceeds 60 ppm, the plastic workability will decrease, so the content should be reduced to 5.
~60ppm. However, in this case, if the oxygen content as an unavoidable impurity exceeds 35 ppm, the C component will be less than 5 ppm, which means that it will be difficult to contain 5 ppm or more of the C component to ensure the desired high strength. Therefore, the oxygen content must be 35 ppm or less. (c) Group 1 metals In addition to improving strength, these components
It has the effect of preventing deformation and burr generation during press punching, but if the content is less than 0.005%, the desired effect will not be obtained, while if the content exceeds 2%, the electrical conductivity will decrease. Therefore, the content was set at 0.005 to 2%. (d) Group 2 metals These components all have a deoxidizing effect and also have the effect of improving electrical conductivity, plating properties, and soldering properties, but their content is
If the content is less than 0.001%, the desired effect cannot be obtained in the above action, while if the content exceeds 1%, the above action tends to deteriorate. Therefore, the content was set at 0.001 to 1%. . (e) Group 3 metals These components have the effect of improving strength and heat resistance, but if their content is less than 0.005%, the desired effect cannot be obtained; If the content exceeds 0.005% to 2%, the conductivity will decrease.
%. In addition, as mentioned above, in this type of conventional Cu alloy, the average grain size of crystal grains: 20 to 100 μm, the average grain size of precipitates: 0.5 to 3 μm, and the average grain size of crystal grains: 60 to 100 μm. 200μm, but with this microstructure, it is not possible to secure the desired high strength and high elongation. By setting the average grain size: 0.1μm or less and the average crystal grain size: 50μm or less, that is, by satisfying all of these conditions, it is possible to achieve a tensile strength of 52Kgf/mm2 ^or more. It is possible to ensure strength and high elongation of 6.2% or more, and this also significantly improves press punching properties. Therefore, even if the average particle size of any of the crystallized substances, precipitates, and crystal grains exceeds the above upper limit, the above-mentioned high strength and high elongation cannot be ensured. [Example] Next, the Cu alloy lead material of the present invention will be specifically explained using Examples. Using an ordinary low-frequency groove induction furnace, the Cu raw material is covered with a graphite plate and melted in an Ar atmosphere. After melting, when the temperature of the molten metal rises to a predetermined temperature within the range of 1220 to 1480 °C, the Ar gas is The molten metal is degassed and stirred by blowing in CO gas, and then alloy components are added to the molten metal under stirring, and finally CO gas is blown in to reduce the oxygen content as an unavoidable impurity to 35 ppm. In addition, the C content was adjusted to a predetermined content within the range of 5 to 60 ppm to obtain a molten metal having the component composition shown in Table 1, and then water-cooled in the same Ar atmosphere. Using a mold, planar shape: 50mm x height: 100mm
An ingot with the dimensions of
After hot-rolling at a predetermined hot-rolling start temperature within the range of 800 to 950℃ to obtain a hot-rolled sheet with a thickness of 11 mm, it is rapidly cooled with water spray to form crystals without forming precipitates. The material and crystal grains were made fine, and then the upper and lower sides of this hot-rolled sheet were faceted by 0.5 mm each to a thickness of 10 mm, and then cold rolled to a thickness of:
A 2 mm cold-rolled plate is made, and this cold-rolled plate is aged at a predetermined temperature within the range of 400 to 550°C for 60 minutes to finely precipitate precipitates, and then cold-rolled. Thickness: 0.7mm, followed by 400mm
After performing strain relief annealing under the conditions of holding at a predetermined temperature within the range of ~500°C for 60 minutes, final cold rolling was performed to obtain a thickness of 0.3 mm, thereby producing the Cu alloy lead material 1 of the present invention. 20 were produced each. Furthermore, regarding the Cu alloy lead materials 1 to 20 of the present invention obtained as a result, crystallized substances, precipitates, and

【table】

【table】

[Table] In addition to measuring the average grain size of the crystal grains, tensile strength, elongation, electrical conductivity, and softening point were also measured. These results are shown in Table 2. [Effects of the Invention] From the results shown in Table 2, Cu alloy lead materials 1 to 20 of the present invention all have a tensile strength of 52 Kgf/mm ² or more, an elongation of 6.2% or more, and a conductivity of 53% IACS or more. These values indicate that the material fully satisfies the characteristics required for lead materials for semiconductor devices, and it is clear that the strength and elongation are even higher. It is. As mentioned above, the Cu alloy lead material of the present invention not only has the electrical conductivity and softening point required of normal Cu alloy lead materials for semiconductor devices, but also has even higher strength and elongation, so it is generally It exhibits excellent performance as a lead material not only for semiconductor devices but also for highly integrated semiconductor devices.

Claims (1)

[Claims] 1 Contains one or two of Cr: 0.05 to 1%, Zr: 0.005 to 0.3%, C: 5 to 60 ppm, and the remainder is Cu and unavoidable impurities ( However, the composition (wt%) consists of (oxygen content of 35 ppm or less), and the structure shows that the average grain size of the crystallized product is 10 μm or less, the average grain size of the precipitate is 0.1 μm or less, and the average crystal grain size is 10 μm or less. A Cu alloy lead material for semiconductor devices having high strength and high elongation, characterized by being composed of a Cu alloy that satisfies the following: grain size: 50 μm or less. 2 Contains one or two of Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Ni, Sn, Fe, Co, and Be. One or more of these: 0.005 to 2%, with the remainder consisting of Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less) (wt%), and the structure is crystalline. The average grain size of precipitates: 10 μm or less, the average grain size of precipitates: 0.1 μm or less, and the average grain size of crystal grains: 50 μm or less.It has high strength and high elongation. Cu alloy lead material for semiconductor devices. 3 Contains one or two of the following: Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Mg, Si, Al, Zn, Mn, B , P, Li, Y, and one or more of rare earth elements:
0.001 to 1%, with the remainder consisting of Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less) (wt%), and the average particle size of the crystallized material is 10 μm or less based on the structure. A Cu alloy lead material for a semiconductor device having high strength and high elongation, characterized in that it is made of a Cu alloy that satisfies the following: , average grain size of precipitates: 0.1 μm or less, average grain size of crystal grains: 50 μm or less. 4 Contains one or two of the following: Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Ti, Nb, V, Ta, Hf, Mo , and one or more of W: 0.005 to 2%, with the remainder consisting of Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less) (wt%), and High strength characterized by being composed of a Cu alloy that satisfies the following in terms of structure: average grain size of crystallized particles: 10 μm or less, average grain size of precipitates: 0.1 μm or less, average grain size of crystal grains: 50 μm or less. and Cu alloy lead material for semiconductor devices with high elongation. 5 Contains one or two of the following: Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Ni, Sn, Fe, Co, and Be. One or more of these: 0.005 to 2%; One or more of Mg, Si, Al, Zn, Mn, B, P, Li, Y, and rare earth elements:
0.001 to 1%, with the remainder consisting of Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less) (wt%), and the average particle size of the crystallized material is 10 μm or less based on the structure. A Cu alloy lead material for a semiconductor device having high strength and high elongation, characterized in that it is made of a Cu alloy that satisfies the following: , average grain size of precipitates: 0.1 μm or less, average grain size of crystal grains: 50 μm or less. 6 Contains one or two of the following: Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Ni, Sn, Fe, Co, and Be. Contains one or more of these: 0.005-2%, one or more of Ti, Nb, V, Ta, Hf, Mo, and W: 0.005-2%, and the rest is Cu. and unavoidable impurities (however, the oxygen content is 35 ppm or less) (wt%), and in terms of structure, the average particle size of the crystallized product: 10 μm or less, the average particle size of the precipitate: 0.1 μm or less, A Cu alloy lead material for semiconductor devices having high strength and high elongation, characterized by being composed of a Cu alloy that satisfies the following: average grain size of crystal grains: 50 μm or less. 7 Contains one or two of the following: Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Mg, Si, Al, Zn, Mn, B , P, Li, Y, and one or more of rare earth elements:
Contains 0.001 to 1%, one or more of Ti, Nb, V, Ta, Hf, Mo, and W: 0.005 to 2%, and the rest is Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less), and in terms of structure, the average grain size of crystallized products: 10 μm or less, the average grain size of precipitates: 0.1 μm or less, and the average grain size of crystal grains: 50 μm or less A Cu alloy lead material for semiconductor devices having high strength and high elongation, characterized by being composed of a Cu alloy that satisfies the following. 8 Contains one or two of Cr: 0.05-1%, Zr: 0.005-0.3%, C: 5-60ppm, and further contains Ni, Sn, Fe, Co, and Be. One or more of these: 0.005 to 2%; One or more of Mg, Si, Al, Zn, Mn, B, P, Li, Y, and rare earth elements:
Contains 0.001 to 1%, one or more of Ti, Nb, V, Ta, Hf, Mo, and W: 0.005 to 2%, and the rest is Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less), and in terms of structure, the average grain size of crystallized products: 10 μm or less, the average grain size of precipitates: 0.1 μm or less, and the average grain size of crystal grains: 50 μm or less A Cu alloy lead material for semiconductor devices having high strength and high elongation, characterized by being composed of a Cu alloy that satisfies the following.