JPS6338413B2 - - 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 the above-mentioned properties, there is a growing demand for even higher strength, and there is a strong desire to develop a Cu alloy lead material that has properties that can fully meet this demand. [Means for Solving the Problems] Therefore, from the above-mentioned viewpoint, the present inventors developed a Cu alloy lead material for semiconductor devices that has the characteristics required and also has even higher strength. As a result of conducting research to develop an alloy lead material, we found that it contained one or two of the following in weight% (hereinafter % indicates weight%): Cr: 0.05-1%, Zr: 0.005-0.3%. , 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%, Mg , Si, Al, Zn, Mn, B, P, Li, Y, and one or more rare earth elements (hereinafter referred to as 2nd group metals): 0.001 to 1%, Ti, Nb, One or more of V, Ta, Hf, Mo, and W (hereinafter referred to as 3rd group metals): 0.005 to 2%, any of the above 1st to 3rd group metals, or 2
The lead material is made of a Cu alloy with a composition of at least 100% Cu and the rest is Cu and unavoidable impurities (however, the oxygen content is 35ppm or less).Tensile strength: 50Kgf/ ^mm2 or more, elongation: 6% As described above, the Cu alloy lead material has the following characteristics: conductivity: 50% IACS or higher, softening point: 400°C or higher, and Cu alloy lead material with these characteristics is fully satisfactory as a lead material 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 will occur. It has become easier to
Since the plating properties and conductivity will decrease, the content should be reduced to 0.05 to 1% for Cr and 0.005 for Zr.
It was set at ~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, plastic workability will decrease, so this 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.
%. [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
Hot rolling is performed at a predetermined hot rolling start temperature within the range of 800 to 950°C to obtain a hot-rolled sheet with a thickness of 11 mm. After water cooling, the top and bottom surfaces of the hot-rolled sheet are faceted by 0.5 mm each. The thickness is 10mm, and then cold rolling and annealing are alternately repeated under normal conditions to obtain a strip with a thickness of 0.3mm. Cu alloy lead materials 1 to 20 of the present invention were manufactured by subjecting them to strain relief annealing at a predetermined temperature. Then, the tensile strength, elongation, electrical conductivity, and softening point of the Cu alloy lead materials 1 to 20 of the present invention obtained as a result were measured. These results are shown in Table 1. [Effect of the invention] From the results shown in Table 1, Cu alloy lead materials 1 to 20 of the present invention all have the following properties:

【table】

[Table] Tensile strength of 51Kgf/ ^mm2 or more, elongation of 6.2% or more, electrical conductivity of 52%IACS or more, and softening point of 410℃ or more. These values are required for lead materials for semiconductor devices. It is clear that the properties are fully satisfied and the strength is even higher. As mentioned above, the Cu alloy lead material of the present invention not only has the elongation, electrical conductivity, and softening point required of ordinary Cu alloy lead materials for semiconductor devices, but also has even higher strength. 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 ( A Cu alloy lead material for semiconductor devices having high strength, characterized in that it is made of a Cu alloy having a composition (within weight %) with an oxygen content of 35 ppm 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. Contains one or more of the following: 0.005 to 2%, with the remainder consisting of Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less) (by weight). Cu alloy lead material for semiconductor devices with high strength. 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%, and the remainder is Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less). Cu alloy lead material for equipment. 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%, and the remainder is Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less) (by weight). A Cu alloy lead material for semiconductor devices having high strength. 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%, and the remainder is Cu and unavoidable impurities (however, the oxygen content is 35 ppm or less). Cu alloy lead material for equipment. 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. A Cu alloy lead material for semiconductor devices having high strength, characterized in that it is made of a Cu alloy having a composition (by weight %) consisting of and unavoidable impurities (however, the oxygen content is 35 ppm 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 A Cu alloy lead material for semiconductor devices having high strength, characterized in that it is made of a Cu alloy having a composition (weight% of 35 ppm or less). 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 A Cu alloy lead material for semiconductor devices having high strength, characterized in that it is made of a Cu alloy having a composition (weight% of 35 ppm or less).