JPS5829622B2 - Assembly method of press-contact type semiconductor device with control electrode terminal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of assembling a pressure contact type semiconductor device with a control electrode terminal.

Taking a thyristor device as an example, the assembled state of the conventional example will be explained in the vertical cross-sectional view shown in FIG. 1, and its main components in the enlarged plan view and enlarged longitudinal cross-sectional view shown in FIGS. 2 to 7. do.

In FIG. 1, reference numeral 1 denotes a thyristor element structure of a thyristor device, and this thyristor element structure 1 is shown in an enlarged longitudinal sectional view in FIG.

In FIG. 2, 11 is a n-type substrate, 12 and 13 are respectively a p-type anode diffusion region and a p-type gate diffusion region formed on the opposing main surfaces of the n-type substrate 11, and 14 is a central part of the p-type gate diffusion region 13. An annular n-type cathode diffusion region 15 formed in a surrounding ring shape, each pn between the n-type substrate 11, the p-type anode diffusion region 12, and the p-type gate diffusion region 13;
An oxide insulating film that protects the exposed portion of the junction, 16 a gate electrode formed on the p-type gate diffusion region 13 inside the annular n-type cathode diffusion region 14 , and 17 formed on the annular n-type nuclear diffusion region 14 An annular cathode 18 indicates an anode support plate, which is made of, for example, a tungsten plate or a molybdenum plate and is attached to the p-type anode diffusion region 12 with low resistance and supports the n-type substrate 11.

In FIG. 1, 2 is a package that houses the thyristor element structure 1 in order to prevent the performance of the thyristor element structure 1 from deteriorating due to external atmosphere, and FIG. 3 shows an enlarged view of this package 2. , FIG. 3a is a plan view thereof, and FIG.

In FIGS. 3a and 3b, 21 is a ceramic cylinder made of, for example, aluminum oxide porcelain, and has an inner diameter that allows positioning of the anode support plate 18 of the thyristor element structure 1, and 22 is made of, for example, a Kovar member. Flange-shaped flat plate glued to the 1st+7) end surface of the body 21, 2
3 is an annular flat plate made of the same member as the brim-shaped flat plate 22 and is bonded to the second end surface of the ceramic cylinder 21; 24 is a metal member such as copper, which is bonded to the inner surface of the annular flat plate 23, and is the annular cathode. a cylindrical cathode terminal having an outer diameter substantially the same as the outer diameter of the annular cathode 17; 26 is a horizontal groove provided in the radial direction of the cylindrical cathode terminal 24 and connected to the circular recess 25; 27 is a thin metal tube such as Kovar material, which protrudes from the side wall of the ceramic cylinder 21 and is bonded to the side wall; The attached gate electrode terminal is shown.

In FIG. 1, reference numeral 3 denotes a gate lead wire made of a fine wire such as copper, which is pressed into contact with the gate electrode 16 of the thyristor element structure 1 and electrically connects the gate electrode 16 and the gate electrode terminal 27 of the package 2; This gate lead wire 3 is shown in an enlarged plan view in FIG.

In FIG. 4, reference numeral 31 denotes a gate (IJ) pressure contact portion made of a metal member such as copper, which is provided at one end of the gate lead wire 3 and is in pressure contact with the gate electrode 16; The contact area is set to be no larger than the contactable area of the electrode 16, and the height is set to about 0.2 to 0.3 square centimeters.

Reference numeral 32 denotes an insertion portion for a gate lead wire inserted into the gate electrode terminal 27.

In FIG. 1, numeral 4 is inserted into the circular recess 25 of the cathode terminal 24 and connects the gate lead pressure contact portion 31 to the gate electrode 16.
A spring 5 is made of an insulating member and slides onto the inner surface of the circular recess 25 of the cathode terminal 24. This is a gate lead insulating support that supports the gate lead wire 3 so that the gate lead pressure contact part 31 can be pressed against the gate electrode 16.
5A is a plan view thereof, and FIG. 5A is a longitudinal sectional view taken along the line VB-VB of FIG. 5A.

In FIGS. 5a and 5b, reference numeral 51 denotes a gate lead insertion hole into which the insertion portion 32 of the gate lead wire 3 is inserted and supported;
indicates a lateral groove extending diametrically from the side surface of the gate lead insulating support 5 beyond the gate lead insertion hole 51.

As shown in FIG. 1, the circular recess 25 of the cathode terminal 24
When the spring 4 is inserted into the spring 4 and the gate lead insulating support 5 is stacked on top of the spring 4, the gate lead is placed so that the gate lead insulating support 5 protrudes about 2 to 3 mm from the end surface of the cathode terminal 24. The height H of the insulating support 5 is set.

6 is an insulating tube into which the gate lead wire 3 is inserted, and this insulating tube 6 is used when the gate lead wire 3 is inserted into the gate lead insertion hole 51 of the gate lead insulating support 5 as shown in FIG. Then, bend this gate lead wire 3 along the horizontal groove 52 of the gate lead insulating support 5, and connect it to the cathode terminal 24.
This is to prevent the gate lead wire 3 inserted into the tubular gate electrode terminal 27 through the lateral groove 26 from coming into contact with the cathode terminal 24.

Reference numeral 7 is a molybdenum plate having a thickness of approximately 0.1 to 1 mm and having a coefficient of thermal expansion approximately equal to that of the n-type substrate 11 of the thyristor element structure 1, and is interposed between the annular cathode 17 and the cathode terminal 24. An annular cathode pressure contact plate that is pressed against 17,
Since the thermal expansion coefficients of the annular cathode pressure contact plate 7 and the n-type substrate 11 are similar, it is possible to prevent strain stress from occurring in the n-type substrate 11 when the temperature of the n-type substrate 11 increases. .

FIG. 6 shows an enlarged view of this annular cathode pressure contact plate 7, FIG. 6a is a plan view thereof, and FIG. 6 or VIB-VIB of FIG.
FIG.

In FIGS. 6a and 6b, reference numeral 71 is an insertion hole provided in the annular cathode pressure contact plate 7 into which the gate lead insulating support 5 is inserted.
The annular cathode pressure contact plate 7 can be positioned by setting the inner diameter of the annular cathode pressure contact plate 7 to be substantially the same as the inner diameter of the annular cathode pressure contact plate 7 and inserting the gate lead insulating support 5 into the insertion hole 71.

Reference numeral 8 denotes an anode terminal that presses against and comes into contact with the anode support plate 18 of the thyristor element structure 1 made of, for example, an iron plate or an iron-nickel alloy plate. FIG. 7 shows an enlarged view of this anode terminal 8. Fig. 7a is a plan view thereof;
The figure is a longitudinal cross-sectional view taken along the line AMIB--B in FIG. 7.

In FIGS. 1a and 1b, 81 is a bowl-shaped portion provided on the anode terminal 8 and having a side surface that expands upward and a flat portion at the bottom;
Reference numeral 2 indicates a peripheral flat portion that extends around the bowl-shaped portion 81 and is welded or soldered to the brim-shaped flat plate 22 of the package 2. The material and thickness t of this anode terminal 8, and the bowl-shaped portion 8
By setting the diameter of 1 and the depth d to respective required values, the anode support plate 1 of the thyristor element structure 1 is
8 can be applied with a required pressing force.

In this assembled state, as shown in FIG. 1, the thyristor element structure 1 is lifted by the elastic force of the springs 4, so that the annular cathode 17 of the thyristor element structure 1 and the annular cathode A gap is created between the pressure contact plate 7 and a gap between the brim-shaped flat plate 22 of the package 2 and the peripheral flat portion 82 of the anode terminal 8.

Therefore, the anode terminal 8 is pressed from the direction of the arrow P using a pressure jig (not shown) to remove the gap, and the brim-shaped flat plate 22 of the package 2 and the peripheral flat part 82 of the anode terminal 8 are separated. be welded or brazed.

At this time, by shaping the bowl-shaped portion 81 of the anode terminal 8 into a desired shape, the annular cathode 17 and the cathode terminal 24 of the package 2 are connected via the annular cathode pressure contact plate 7, and the anode of the thyristor structure 1 is connected. A required contact pressure can be applied between the support plate 18 and the bowl-shaped portion 81 of the cathode terminal 8, respectively, and at the same time, the elastic force of the spring 4 can be applied to the gate electrode 16 of the thyristor element structure 1 and the gate lead wire. 3 can be applied with the required contact pressure.

The tip of the gate electrode terminal 27 of the package 2 into which the gate lead wire 3 has been inserted is pressure bonded.

Next, the details of the assembly work of the above-mentioned thyristor device will be described for each work step.

In the first step, first the cathode terminal 24 of the package 2
Insert the spring 4 into the circular recess 25 of.

Next, insert the gate lead wire 3 into the gate lead insertion hole 51 of the gate lead insulating support 5 as shown in FIG.
This gate lead wire 3 is connected to the gate lead insulating support 5.
Bend it along the horizontal groove 52.

Next, this bent gate lead wire 3 is inserted into the insulating tube 6, and then the gate lead wire 3 into which this insulating tube 6 has been inserted is inserted into the horizontal groove 26 of the cathode terminal 24, and the insertion portion 32 is inserted into the horizontal groove 26 of the cathode terminal 24. At the same time as the gate electrode terminal 27 is inserted, the above gate) IJ - the gate into which the gate wire 3 is inserted
- Place the electrode insulating support 5 on top of the spring 4 already inserted into the circular recess 25 of the cathode terminal 24.

At this time, the tip of the gate lead insulating support 5 is set to protrude from the end surface of the cathode terminal 24 by 2 to 3 mm.

Hereinafter, the above-mentioned fourth stage will be referred to as the gate pressure contact mechanism assembly; erecting stage.

In the second step, an annular cathode pressure contact plate 7 is inserted into the tip of the IJ-doped insulating holder 5 protruding from the end face of the cathode terminal 24, and then a thyristor element structure is inserted into the annular cathode pressure contact plate 7. The thyristor element structure 1 is inserted so that the annular cathode 1) 17 is in contact with the thyristor element structure 1.

Next, the anode support plate 18 of the thyristor element structure 1
The anode terminal 8 is placed on the anode support plate 18 so that the bowl-shaped portion 81 of the anode terminal 8 is in contact with the anode terminal 8 .

Hereinafter, the second stage i will be referred to as the main electrode pressure contact mechanism assembly stage.

In a third step, the anode terminal 8 is pressed from the direction of arrow P using a pressure jig, and the peripheral flat part 82 of the anode terminal 8 and the brim-shaped flat plate 22 of the package 2 are welded or brazed, Next, the tip of the gate electrode terminal 27 and the insertion portion 32 of the gate lead wire 3 are pressure-bonded.

Hereinafter, the third step will be referred to as the package sealing step.

By the way, in the structure of the conventional thyristor device, since the gate pressure contact mechanism is complicated, the number of steps in the assembly stage for assembling the gate pressure contact mechanism is large, resulting in poor workability.

Furthermore, when the thyristor element structure 1 moves in the axial direction of the ceramic cylinder 21 of the package 2 due to an impact after the main electrode pressure contact mechanism is assembled, the gate lead insulating support 5 also moves. However, when the axial height of the pressure contact portion 31 of the gate lead wire 3 is high, the gate lead insulating support 5 is pushed down into the circular recess 25 due to the above fluctuation, and the annular cathode pressure contact plate 7 is positioned. It becomes impossible to connect the annular cathode pressure contact plate 7 and the contact portion
1 will come into contact with each other, causing a short circuit.

In order to prevent this cause of failure, there is a drawback that it becomes impossible to apply the required pressure contact force to the gate electrode 16 to reduce the axial height of the pressure contact part 31.

Furthermore, since a pressurizing means using the spring 4 is required to press the press-contact portion 31 to the gate electrode 16, the height of the cathode terminal 24 of the package 2 in the axial direction increases, making it difficult to downsize the thyristor device. It also had the disadvantage of being difficult.

The present invention has been made in view of the above-mentioned drawbacks, and simplifies the control electrode pressure contact mechanism by using a control electrode spring lead made of a conductive elastic member. By inserting the semiconductor element structure into the package after assembling the semiconductor element structure into the main electrode terminal of the main electrode terminal, the assembly work efficiency is improved and the control electrode of the semiconductor element structure is prevented from being damaged by the control electrode spring lead. It is an object of the present invention to provide a method for assembling a press-contact type semiconductor device with a control electrode terminal that can reduce the amount of noise.

Next, a method of assembling a thyristor device according to an embodiment of the present invention will be described.

Among the components of the thyristor device assembled by the method of this embodiment, the thyristor element structure, the package, and the anode terminal are the thyristor element structure 1, package 2, and anode terminal shown in FIGS. 2, 3, and 7, respectively. Since it is similar to terminal 8, its explanation will be omitted.

FIG. 8 is a front view showing a gate spring lead which is a component of the thyristor device assembled by the method of this embodiment.

In the figure, a gate spring lead 3a is made of a conductive elastic member and corresponds to the gate lead wire 3 shown in FIG. The pressure contact portion 32a is an insertion portion of the gate spring lead 3a corresponding to the insertion portion 32 of the gate lead wire 3.

Note that the insertion portion 32a of this gate spring lead 3a
The gate electrode terminal 27 of the package 2 is shown in FIG.
There is no need to press and bond the device inside the device, and it is only necessary to insert it lightly.

Further, when the insertion portion 32a is inserted into the gate electrode terminal 27, the pressure contact portion 31a is arranged so that the raw end of the pressure contact portion 31a protrudes by about 2 to 3 spaces from the end surface of the cathode terminal 24 of the package 2.
Set the length Ll of a.

Further, a bent part is provided on the gate spring lead 3a to help position the required length of the insertion part 32a of the gate spring lead 3a when inserting it into the gate electrode terminal 27 of the package 2. If the length L2 at the center 1 of the 31a is set to be approximately equal to the inner radius of the ceramic cylindrical body 21 of the package 2, the pressure contact portion 31a can be easily positioned approximately at the center of the circular recess 25 of the cathode terminal 24. be able to.

FIG. 9a is an enlarged plan view showing an annular cathode pressure contact plate fitted with an insulating support, which is a component of a thyristor device assembled by the method of the embodiment of the present invention;
It is a sectional view taken along the IXB line.

In the figure, 7a denotes an insertion hole of the annular cathode pressure contact plate 7 shown in FIG. 6 for a gate spring lead insulating support 5 similar to that shown in FIG. 5 that supports the gate spring lead 3a shown in FIG. 8. 71 is an annular cathode pressure contact plate fitted with an insulating support.

Note that the insertion hole 5 of the gate spring lead insulating support 5
1 and the lateral groove 52 are not so required,
It is sufficient that the pressure contact portion 31a of the gate spring lead 3a can be prevented from falling over.

Furthermore, the dimensional accuracy relationship between the outer diameter of the gate spring lead insulating support 5 and the inner diameter of the circular recess 25 of the cathode terminal 24 of the package 2 shown in FIG. It is sufficient that it can be inserted lightly into the circular recess 25.

Next, each assembly step of the method of this embodiment is to assemble a thyristor device using the above-described thyristor element structure 1, package 2, anode terminal 8, gate spring lead 3a, and insulating support fitting annular cathode pressure contact plate 7a. The first
The longitudinal cross-sectional view shown in Figure 0 a''-'c will be explained.

First, as shown in FIG. 10a, in the gate pressure contact mechanism assembly stage, the insertion portion 32a of the gate spring lead 3a is
is inserted into the gate electrode terminal 27 from the lateral groove 26 of the cathode terminal 24 of the package 2, and then the pressure contact portion 31a of the gate spring lead 3a is fitted onto the insulating support.The gate spring lead insulating support of the annular cathode pressure contact plate 7a 5 insertion hole 5
1 and the gate spring lead 3a.
The gate spring lead insulating support 5 is inserted into the circular recess 25 of the cathode terminal 24 while being inserted into the lateral groove 52, and the annular cathode pressure contact plate 7 is placed on the cathode terminal 24.

Next, as shown in FIG. 10, in the main electrode press-contacting mechanism assembly stage, the thyristor element structure 1 is brought into contact with the gate electrode 16 of the thyristor element structure 1 and the press-contact portion 31a of the gate spring lead 3a. is inserted into the ceramic cylindrical body 21 of the package 2, and the anode terminal 8 is inserted into the ceramic cylindrical body 21 so that the anode support plate 18 of the thyristor element structure 1 and the bowl-shaped portion 81 of the anode terminal 8 are in contact with each other. insert.

At this time, since the thyristor element structure 1 is lifted by the elastic force of the gate spring lead 3a,
A gap is created between the annular cathode 17 of the thyristor element structure 1 and the annular @pole pressure contact plate 7, and a gap is also created between the brim-shaped flat plate 22 of the package 2 and the peripheral flat portion 82 of the anode terminal 8. ing.

Finally, as shown in FIG. 10C, in the package sealing step, the anode terminal 8 is pressed from the direction of arrow P using a pressure jig (not shown), and the annular cathode 17 and the annular cathode pressure contact plate are pressed. 7 and the brim-shaped flat plate 22 and the peripheral flat part 82
After that, the brim-like flat plate 22 and the peripheral flat part 82 are welded or brazed, and then only the tip of the gate electrode terminal 27 is pressure bonded.
The assembly work of the thyristor device according to the example method is completed.

In the thyristor device assembled in this way, the elastic force of the anode terminal 8 causes the annular cathode 17 and the cathode terminal to be connected between the bowl-shaped portion 81 of the anode terminal 8 and the anode support plate 18, and via the annular cathode pressure contact plate γ. At the same time, due to the elastic force of the gate spring lead 3a, the required contact pressure can be applied between the pressure contact part 31a and the gate electrode 16, and between the insertion part 32a and the gate electrode terminal 27. The required contact pressure can be applied.

In the method of this embodiment, by using the gate spring lead 3a and the annular cathode pressure contact plate 7a fitted with an insulating support, the gate pressure contact mechanism is simplified and the number of required components is reduced compared to the conventional example. Since the spring lead insulating support 5 and the annular cathode press-contact plate 7 are never separated, there is no need to take much care in assembling the gate press-contact mechanism, and even a non-skilled worker can assemble the gate press-contact mechanism. This makes it possible to improve the workability at the stage of assembling the gate pressure contact mechanism shown in FIG. 10a.

Furthermore, in the main electrode press-contacting mechanism assembly stage shown in FIG. .

Furthermore, even if the thyristor element structure 1 moves in the axial direction of the ceramic cylinder 21 due to a sudden impact after the main electrode press-contact mechanism assembly step is completed, the gate spring lead insulating support 5 and the annular cathode press-contact plate will not move. Since the annular cathode press-contact plate 7 and the press-contact portion 31a of the gate spring lead 3a do not come into contact with each other, there is no risk of short-circuit failure.

Furthermore, by inserting the thyristor element structure 1 into the ceramic cylinder 21 of the package 2 at this assembly stage, the pressure contact portion 31a of the gate spring lead 3a is removed.
Since the gate electrode 16 can be easily brought into contact with the gate electrode of the thyristor element structure 1, it is possible to prevent the gate electrode 16 from being damaged by the pressure contact portion 31a of the gate spring lead 3a.

In this embodiment, a method for assembling a thyristor device in which the annular cathode pressure contact plate 7 is interposed between the annular cathode 17 and the cathode terminal 24 has been described. The present invention can also be applied to a method of assembling a thyristor device using a thyristor element structure.

In 1, the case of assembling a thyristor device has been described as an example, but the present invention is not limited to this. The present invention can also be applied to the case of assembling a semiconductor device having a semiconductor element structure as a component.

As described above, in the method for assembling a press-contact type semiconductor device with a control electrode terminal of the present invention, the control electrode press-contact mechanism is simplified using the control electrode spring lead made of a conductive elastic member, and the control electrode After the spring lead is assembled into the package having the first main electrode terminal and the semiconductor element structure is inserted into the package, the package is sealed with the second main electrode terminal having elastic force, so that the control described above is performed. The workability of assembling the electrode pressure contact structure can be improved.

In the past, it was possible to measure the electrical characteristics of a control electrode of the semiconductor element structure while the semiconductor element structure was inserted into the package, and the control electrode was damaged by the control electrode spring lead. can be suppressed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an assembled state of an example of a conventional thyristor device, FIGS. 2 to 7 are an enlarged plan view and an enlarged longitudinal sectional view showing the main components of the conventional example, and FIGS. 9 is an enlarged plan view and an enlarged longitudinal sectional view showing the components of a thyristor device assembled by the method of an embodiment of the present invention, and FIGS. 10a and 10c are for explaining each assembly step of the method of the above embodiment In the figure, 1 is a thyristor element structure (semiconductor element structure), 16 is a gate electrode (control electrode), 1T is an annular cathode (first main electrode), and 18 is an anode support plate ( 2 is a package, 2F is a ceramic cylinder (insulating cylinder), 24 is a cathode terminal (first main electrode terminal), 25 is a recess, 26 is a horizontal groove, 27 is a gate electrode terminal (control electrode terminal)
, 3a is a gate spring lead (control electrode spring lead), 5 is a gate spring lead insulating support (insulating support), and 8 is an anode terminal (second main electrode terminal). In addition, the same reference numerals in the drawings respectively Indicates the same or equivalent part.

Claims (1)

[Claims] 1 Semiconductor element configuration in which a control electrode and a ring-shaped first main electrode formed to surround the control electrode are provided on a fourth main surface, and a second main electrode is provided on a second main surface. In a method for assembling a press-contact type semiconductor device with a control electrode terminal that seals a body, an insulating cylindrical body having an inner diameter slightly larger than an outer diameter of the semiconductor structure, and an outer peripheral portion on a first end surface of the insulating cylindrical body. a cylindrical first main electrode terminal to which is bonded and which should abut the first main electrode inside the insulating cylinder; a recessed portion provided in the center of the surface and having approximately the same diameter as the inner diameter of the first main electrode; and a radial recessed portion of the first main electrode terminal that is to be in contact with the first main electrode. a control electrode terminal having a lateral groove extending from the outer periphery to the recess, and a lead wire insertion hole that is attached to a side wall of the insulating cylindrical body opposite to the lateral groove by penetrating the same and opening into the insulating cylindrical body; The first end side of the control electrode spring lead made of a conductive elastic member is inserted into the lead wire insertion hole of the package, and the second end side is inserted into the lateral groove and the recess. The part inserted into the lead wire insertion hole through the opening communicating with the lateral groove of the insulating support is fixed, and the first main electrode terminal is inserted from the four parts by the elastic force of the part other than that part. a first step of pushing out a predetermined length above the surface to be brought into contact with the first main electrode; a tip of the control electrode spring lead pushed out from the recess of the control electrode spring lead; a second step of inserting the control electrode into contact with the second main electrode terminal of the semiconductor element structure inserted into the package; The first main electrode is brought into pressure contact with the first main electrode terminal by the elastic force of the second main electrode terminal, and the tip of the control electrode spring lead is brought into pressure contact with the control electrode. A third step of bonding the outer circumferential portion of the second main electrode terminal to the second end surface of the insulating cylinder in such a manner as to
A method for assembling a press-contact type semiconductor device with a control electrode terminal, comprising the steps of: