JPS6360533B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device in which a semiconductor element having a large number of convex electrodes is fixed to a substrate made of ceramic or the like.

Conventionally, in this type of face-down bonding type semiconductor device, in order to avoid mechanical damage due to thermal stress applied to the protruding electrode, the protruding electrode was placed in the center of the semiconductor element, which required a rather difficult process. I was picking. Furthermore, when electrodes are provided on the periphery of a semiconductor element, there is a limit to the size of the element, and this face-down bonding method cannot be applied to large elements.

The present invention has been made to eliminate the above-mentioned drawbacks, and an object of the present invention is to provide a semiconductor device that can prevent thermal stress from being applied to the convex electrode and provide a highly reliable connection between the element and the substrate. purpose.

In the semiconductor device according to the present invention, a supporter made of the same material as the substrate is fixed to the surface of the semiconductor element opposite to the surface having the convex electrode.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of this embodiment. Reference numeral 1 denotes a substrate on which one or more semiconductor elements 2 are mounted, and is usually made of ceramic or glass epoxy material. 3 indicates a protruding electrode for electrically and mechanically connecting the semiconductor element 2 and the substrate 1, and is a so-called "bump" in which a protrusion is provided on both or one of the semiconductor element 2 and the substrate 1. be. Further, 4 is a supporter made of the same material as the substrate 1;
is the adhesive layer.

Further, FIG. 2 is a schematic diagram for explaining the amount of displacement when a bump is displaced when a semiconductor device is subjected to a temperature cycle, in which a shows a conventional device and b shows a device according to this embodiment. There is.

Hereinafter, the functions of the supporter 4 in this embodiment will be explained in detail using these figures.

Bumps are usually made of a soft material such as solder, and are relatively mechanically weak. In conventional semiconductor devices, when subjected to temperature cycles, thermal stress is applied to the weak bumps due to the difference in thermal expansion between silicon and the substrate. Second
As shown in Figure a, the bumps 3 were distorted and destroyed, resulting in a defective device.

In this embodiment, a supporter 4 made of the same material as the substrate 1 and having a thickness sufficient to restrain the semiconductor element 2 is provided on the surface opposite to the surface having the convex electrode 3, and an adhesive layer 5 is provided. It is fixed by

As a result, when the device undergoes a thermal cycle, the substrate 1 and the supporter 4 expand and contract in the same way,
As shown in FIG. 2b, the semiconductor element 2 is also supported by the supporter 4.
Since the bump 3 expands and contracts in substantially the same way, the displacement of the bump 3 can be made smaller than in the past. Therefore, when a supporter is provided as in this embodiment, it is possible to prevent bump destruction at a low cycle as in the conventional case without a supporter, and the biggest defect in mounting the face-down bonding method is alleviated. However, the life of the device can be extended by temperature cycling.

Note that the supporter 4 may be simply plate-shaped, but it is also possible to provide means for improving heat dissipation characteristics and through-holes for taking out electrodes to the outside.

Further, although not shown in the drawings, the present invention provides a substrate 1
It goes without saying that the present invention can also be applied to a so-called module in which a large number of semiconductor elements 2 are mounted, and in that case, the supporter 4 can have a structure common to a large number of semiconductor elements 2.

As described above, according to the semiconductor device of the present invention, since the supporter made of the same material as the substrate is provided on the surface of the semiconductor element opposite to the surface having the convex electrode, the semiconductor element and the substrate can expand and contract in the same manner. , it is possible to relax the thermal stress on the weakest convex electrode part,
This has the effect of making it possible to apply the face-down bonding method even to large semiconductor devices.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the displacement of bumps due to temperature cycles. 1 is a substrate, 2 is a semiconductor element, 3 is a convex electrode, 4
is a supporter. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. A semiconductor device having a semiconductor element having a convex electrode on one surface, and a substrate connected to the semiconductor element by the convex electrode, the surface of the semiconductor element having the convex electrode and the substrate connected to the semiconductor element by the convex electrode. A semiconductor device characterized in that a supporter made of the same material as the substrate is provided on the opposite surface. 2. The semiconductor device according to claim 1, wherein the substrate is made of ceramic.