JP2508634Y2 - Resin-sealed pin head type semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a resin-sealed pin head type semiconductor element used as a general-purpose electronic component.

[Conventional technology]

FIG. 3 shows an example of the structure of a conventional resin-sealed pin head type semiconductor element, for example, a semiconductor substrate 3 such as a diode.
The end surface 1AA of the header 1A of the lead pin 1 is joined to the respective electrodes on the upper surface and the lower surface thereof by solder 2. An insulating protective film 4 made of, for example, resin is provided around the semiconductor substrate 3. The leads 1B of the lead pins 1 respectively form the electrode leads of this semiconductor element.

[Problems to be solved by the device]

In the resin-sealed pin head type semiconductor element described above,
Since the header of the lead pin needs to be bonded to the entire electrode surface of the semiconductor substrate, the diameter of the end face is usually made larger than the diameter of the semiconductor substrate, and a roundness for relaxing the electric field generated by the applied voltage is formed around the end face. It is provided. However, in the lead pin having such a header, there is a reference that the relational position between the semiconductor substrate and the lead pin is not provided, and there is a problem that positioning is difficult at the time of joining. In addition, excessive solder flows out to the side surface of the header at the time of joining, and the solder adheres to the side surface of the header. Generally, solder is vulnerable to corrosion due to moisture, and when moisture invades, the influence of corrosion of the solder flowing out to the side surface of the header affects the semiconductor substrate,
There is a problem that its characteristics deteriorate.

An object of the present invention is to solve the above-mentioned problems, to easily position the joint between the semiconductor substrate and the lead pin, and to reduce the influence of corrosion of the excess solder flowing out at the time of joining, which is the resin-sealed pin head. Type semiconductor device.

[Means for solving the problem]

In order to solve the above-mentioned problems, in the resin-sealed pin head type semiconductor device of the present invention, a pair of lead pins having a header at one end of a lead, and electrodes on the upper surface and the lower surface sandwiched between the headers have respective headers. In a semiconductor element composed of a semiconductor substrate bonded to the solder by a solder, and an insulating protective film covering the semiconductor substrate, the solder, and the outer surface of the header, the header has the largest diameter part via the solder. A surface end to be joined with the semiconductor device, the diameter of which is the same as the diameter of the semiconductor, and has an inclined portion whose diameter becomes smaller toward the lead side, and an excess solder is disposed on the inclined portion. To do so.

[Action]

In the resin-sealed pin head type semiconductor device of the present invention, the diameter of the semiconductor substrate and the diameter of the header of the lead pin are set to the same size. And match exactly. Further, since the header to which the electrode of the semiconductor substrate is joined is provided with the inclined portion whose diameter becomes smaller toward the lead side, when the header and the semiconductor substrate electrode are joined, the excess solder is removed from the surface end of this inclined portion. As a result, the solder flows in a direction away from the semiconductor substrate, and there is no excess solder between the header and the semiconductor substrate electrode, so that the thickness is substantially uniform, and it is possible to reduce the influence of moisture on the solder at this point.

〔Example〕

FIG. 1 is a cross-sectional view of a resin-sealed pin head type semiconductor device according to an embodiment of the present invention. For example, an end surface 5AA of a header 5A of a lead pin 5 is soldered to electrodes on the upper and lower surfaces of a semiconductor substrate 3 such as a diode. Joined by two. An insulating protective film 4 made of, for example, resin is provided around the semiconductor substrate 3. The leads 5B of the lead pins 5 respectively form the electrode leads of this semiconductor element.

In the present invention, the diameter of the semiconductor substrate and the diameter of the end face of the header of the lead pin are set to be the same size, and an inclination is provided inward from the outer periphery of the end face of the header to which the electrode of the semiconductor substrate is joined.

FIG. 2 is a cross-sectional view showing a method of positioning the semiconductor substrate 3 and the header 5A of the lead pin 5 in the present invention, showing the assembly jig 6 having the hole 6A having an inner diameter slightly larger than the diameter of the semiconductor substrate 3 and the header 5A. The header 5A of each lead pin is inserted into the hole 6A with the semiconductor substrate 3 as the center on both sides. The semiconductor substrate 3 and the headers 5A placed on both sides are positioned with the outer periphery as a reference, and the central axis of the semiconductor substrate 3 and the central axis of each header 5A are correctly aligned.

Further, since the inclination is provided inward from the outer circumference of the end surface of the header to which the electrode of the semiconductor substrate is joined to the lead side inward, excess solder is inclined from the outer circumference of the end surface when the header end surface and the semiconductor electrode are joined. Flowing to the opposite surface of the header away from the semiconductor substrate, and the influence of corrosion due to moisture can be reduced. Further, when the excess solder wraps around from the outer circumference of the end face to the inclined portion, it covers the outer circumference of the end face and rounds the outer circumference to relax the electric field generated by the applied voltage around the end face. In the present invention, it is desirable to use a slightly larger amount of solder in consideration of the electric field relaxation effect when joining the electrodes. Furthermore, the insulating protective film 4 provided around the semiconductor substrate has the same diameter as the semiconductor substrate 3 and the header 5A of the lead pin 5. Therefore, it is easy to form an insulating protective film having a required uniform thickness, and the insulating protection film is formed. The stress of the film is relaxed and the influence on the semiconductor substrate can be suppressed to a minimum. This stress relaxation is particularly effective for thermal cycling.

[Effect of device]

In the resin-encapsulated pin head type semiconductor device of the present invention, the diameter of the semiconductor substrate and the diameter of the header of the lead pin are set to the same size, and they are positioned with reference to their outer circumference so that the central axis of the semiconductor substrate and the central axis of the header are correctly aligned. By doing so, it is possible to obtain a semiconductor element having excellent characteristics and no variation. Further, since the header to which the electrode of the semiconductor substrate is joined is provided with the inclined portion whose diameter becomes smaller toward the lead side, when the header and the semiconductor substrate electrode are joined, the excess solder is removed from the surface end of this inclined portion. As a result, the solder flows in a direction away from the semiconductor substrate, and there is no excess solder between the header and the semiconductor substrate electrode, resulting in a substantially uniform thickness, and it is possible to reduce the corrosion effect of the solder at this location on the solder. Furthermore, since the diameter of the semiconductor substrate and the diameter of the header are equal and the insulating protective film having a uniform thickness can be formed, the influence of the stress of the insulating protective film on the semiconductor substrate,
In particular, the influence on the heat cycle can be minimized. As a result, a high-performance resin-sealed pin head type semiconductor element having excellent electric characteristics, no variation in electric characteristics, and moisture resistance / heat resistance cycle can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a resin-sealed pin head type semiconductor device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing a method of positioning a semiconductor substrate and a lead pin header of FIG. 1, and FIG. It is sectional drawing of a resin-sealed pin head type semiconductor element. 2: Solder, 3: Semiconductor substrate, 4: Insulating protective film, 5: Lead pin, 5A: Header, 5AA: End surface (on the side opposite the header), 5B: Lead (electrode lead), G: Inclined (header end surface 5AA) From the outer circumference to the lead side inward direction).

Claims (1)

(57) [Scope of utility model registration request] 1. A pair of lead pins each having a header at one end of a lead, a semiconductor substrate sandwiched between the headers, each electrode of an upper surface and a lower surface being joined to each header by solder, said semiconductor substrate, solder and In a semiconductor element consisting of an insulating protective film covering the outer surface of the header, the header has a portion with the largest diameter which is a surface end joined to the semiconductor substrate via solder, and the diameter is the diameter of the semiconductor. A resin-sealed pin head type semiconductor element having the same size as the above, and having an inclined portion whose diameter becomes smaller toward the lead side, and excess solder is disposed on the inclined portion.