JPH0345338A - Nickel-molybdenum composite material and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain substrate, the thermal expansion coefficient of which is closely akin to those of various semiconductors by a method wherein nickel- molybdenum laminate is used for substrate, to which semiconductor is to be bonded. CONSTITUTION:Substrate, to which semiconductor is to be bonded, can be made of composite, which is produced by laminating or piling up nickel and molybdenum to each other. In addition, by comparatively freely changing the sheet thicknesses of nickel and of molybdenum composing composite material, composite material, the thermal expansion coefficient of which is closely akin to those intrinsic to various semiconductors, can be obtained comparatively easily. Accordingly, by using the substrate made of said composite material, the fear of the occurrence of fracture, crack, poor bonding and the like in semiconductor at the bonding between the semiconductor and the substrate is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a nickel-molybdenum composite, particularly a nickel-molybdenum alloy composite used for semiconductor substrates.

[Prior Art] Conventionally, silicon has been the mainstream semiconductor used in integrated circuits (ICs), large-scale integrated circuits (LSIs), etc., but this semiconductor has very low mechanical strength and Moreover, it is necessary to prevent deformation due to heat dissipated from the heat generated by the semiconductor chip, so feed having a coefficient of thermal expansion similar to that of the semiconductor chip is used for the substrate to which the semiconductor chip is soldered or bonded. was. For example, tungsten, molybdenum, and copper-molybdenum-copper composites have been used.

[Problems to be Solved by the Invention] However, since silicon is the mainstream semiconductor, tungsten and molybdenum are used for the substrates used for bonding the conventional semiconductor chips mentioned above. , I.C.

As LSIs and other devices become smaller and lighter, semiconductor materials such as germanium (Ge), m-v group compounds (AiSb, GaP, GaAs) are being used in addition to silicon.

GaSb, etc.), II-IV group compounds (ZnS,
ZnSe, ZnTe, CdS, etc.) and other compounds (SiC, B1Te5), etc. have been used.

Since these semiconductors have different thermal expansion coefficients from substrates using tungsten or molybdenum, there is a risk that serious defects such as cracks, cracks, and poor bonding may occur in the semiconductor.

Therefore, one technical problem of the present invention is to obtain a substrate having a thermal expansion coefficient close to that of various semiconductors by using a nickel-molybdenum stack as a substrate to which semiconductors are bonded.

[Means for Solving the Problems] According to the present invention, a nickel-molybdenum composite characterized by laminating nickel and molybdenum is obtained.

Further, according to the present invention, a nickel-molybdenum composite material can be produced by hot rolling a nickel plate and a molybdenum plate after polymerizing them.

[Operation] Nickel and molybdenum are bonded by a pressure bonding method to produce a substrate made of a nickel-molybdenum laminated composite material, and a semiconductor chip is bonded onto the substrate by means such as brazing.

[Example code] Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

In Figure 1, (A) shows a cross-section of a laminated composite material 3 manufactured by sandwiching molybdenum 2 between two layers of nickel 1 and joining them by pressure bonding, and (B) , shows a composite material 3 obtained by laminating nickel 1 and molybdenum 2 by a pressure bonding method.

FIG. 2 shows a nickel plate 10 and a molybdenum plate 20 that are bonded together using the hot press method in the following steps.
A composite material 30 was prepared by polymerizing 0-molybdenum 20-nickel 10.

First, a molybdenum plate 20 with a thickness of 1.0 mm x width of 100 nm x length of 150 nm and a thickness of 1.0 mm x width of 110 m.
Prepare two nickel plates 20 of m x length 170+nm,
Polymerization occurs as shown in Figure 2.

This polymerized member was heated at 750° to 1°C in a hydrogen gas atmosphere.
000 degrees Celsius and perform the first rolling at a rolling ratio of 10 to 50%. By this rolling, the nickel plate 10 and the molybdenum plate 20 are completely brought into close contact with each other.

Next, it is heated again and rolled a second time at a rolling ratio of 5 to 30%. This second and subsequent rolling is repeated an arbitrary number of times depending on the thickness of the final composite substrate. Here, the final thickness is 1°O+nm x width 110mm x length 4
90 cm of hot pressed material 30 was manufactured.

This rolled material 30 is 1.0mm thick x 1.00mm wide x
It was cut into lengths of 400 mm and heated to 900 degrees in a hydrogen gas atmosphere to reduce oxides on the surface.

The physical properties of the composite material obtained by this manufacturing method are as follows.

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Effects of the Invention] As stated above, the present invention can manufacture a substrate to which semiconductors are bonded using a composite material obtained by laminating or polymerizing nickel-molybdenum. Furthermore, by relatively freely changing the thickness of the nickel-molybdenum composite material, it is relatively easy to obtain a composite material with a coefficient of thermal expansion that approximates the coefficient of thermal expansion inherent to various semiconductors. ,
Therefore, by using a substrate made of this composite material,
When the semiconductor and the substrate are bonded, there is less risk of cracks, cracks, poor bonding, etc. occurring in the semiconductor.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a laminated composite material of the present invention, where A shows a three-layer composite of nickel-molybdenum-nickel, and a shows a two-layer composite of nickel-molybdenum. FIG. 2 is a cross-sectional view showing a composite material manufactured by polymerizing a nickel plate and a molybdenum plate. ]...Nickel, 2...Molybdenum, 3...Laminated composite material,...Nickel plate, 0...Molybdenum plate, 0...Polymerized composite material.

Claims (1)

[Claims] 1. A nickel-molybdenum composite material characterized by laminating nickel and molybdenum. 2. A method for producing a nickel-molybdenum composite material, which comprises hot rolling a nickel plate and a molybdenum plate after polymerizing them.