JPH07254620A - Surface mounted semiconductor device - Google Patents

Abstract

PURPOSE:To facilitate fabrication while allowing reduction in the thickness by bonding a single semiconductor substrate of first conductivity type, at the opposite sides thereof, with semiconductor elements of opposite conductivity type while spacing apart from each other and connecting the semiconductor elements with independent lead frames before the entirety is sealed with resin. CONSTITUTION:Two P conductivity type semiconductor regions 1b, 1b' are provided, while spaced apart from each other, on one surface of a single N conductivity type semiconductor substrate 1a to form a PN junction having guard ring structure. The semiconductor regions 1b, 1b' are connected through solder layers 2, 2' with lead frames 3, 3' and then they are entirely sealed with an insulating resin except a part of the lead frame 3, 3' and integrated. Since a pair of adjacent P-N junctions can be cut in parallel, the fabrication is facilitated while allowing reduction in the thickness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount semiconductor device used as a bidirectional varistor, a unidirectional varistor, a surge absorbing element, a diode or the like.

[0002]

2. Description of the Related Art Conventionally, as a bidirectional surface mount type semiconductor device utilizing a reverse drop by a PN junction of a semiconductor element, there is one as shown in FIG. In the structure shown in FIG. 9, a pair of semiconductor elements 1 and 1 ′ having a diode structure have opposite polarities and are connected in series. The semiconductor elements 1 and 1'have the same planar structure and have substantially the same characteristics. The semiconductor elements 1 and 1 ′ are P-conductivity type semiconductor regions 1 b serving as anode regions formed on one surface side of the N-conductivity type silicon substrates 1 a and 1 ′ a serving as cathode regions, respectively.
1'b. In the semiconductor element 1, the N-conductivity type silicon substrate 1a is fixed to the first lead frame 3 via the solder layer 2, and in the semiconductor element 1 ′, the N-conductivity type silicon substrate 1′a has the solder layer 2 ′. It is fixed to the second lead frame 3 ′ via. The P-conductivity type semiconductor region 1b of the semiconductor element 1 is connected to one end of the metal plate 5 via the solder layer 4, and the P-conductivity type semiconductor region 1'b of the semiconductor element 1'is connected via the solder layer 4 '. 5 is connected to the other end. Then, as shown by the chain line, the lead frame 3,
The entire part except for a part of 3'is sealed with an insulating resin to form a resin mold portion 6 to form a bidirectional surface mount type semiconductor device.

Although not shown, for example, in FIG. 9, a semiconductor element 1'is stacked on the semiconductor element 1 and connected in series, and the P-conductivity type semiconductor region 1'b of the semiconductor element 1'is connected to the connecting conductor plate 5. There is also a structure for connecting to the second lead frame 3 '. In this structure, the semiconductor elements 1 and 1 ′ are arranged only on one of the lead frames 3.

[0004]

However, in such a conventional first surface-mounting type semiconductor device, the structure is such that two semiconductor elements having a diode structure are connected by using the connection conductors. Therefore, there are disadvantages that the number of parts increases, the structure of the assembly jig becomes complicated, and the number of assembly processes including the soldering process increases. Further, in the other surface mount type semiconductor device, only on one of the lead frames 3,
Since the stacked semiconductor elements are arranged and the connection conductor is used, in addition to the above-mentioned drawbacks, the height after assembling becomes high and the height of the resin mold portion is inevitably large. Therefore, there is also a problem that the surface-mount type semiconductor device cannot be downsized, especially the height is low, that is, it cannot be made thin.

The main object of the present invention is to eliminate the drawbacks of the conventional surface mount type semiconductor device and to provide a thin surface mount type semiconductor device which is easy to manufacture.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 is a first semiconductor substrate of a single conductivity type formed on one surface side apart from each other. 1
A semiconductor element having first and second semiconductor regions of a second conductivity type opposite to that of the first lead frame and a second lead frame arranged apart from the first lead frame. A second lead frame which is placed on these lead frames so as to be entangled with each other, connects the first semiconductor region to the first lead frame, and separates the second semiconductor region from the first lead frame. The present invention provides a bidirectional surface-mount type semiconductor device, characterized in that the whole of the lead frame except for a part thereof is sealed with resin and integrated.

In order to solve the above-mentioned problems, the second aspect of the present invention is that the first conductivity type is formed separately from one surface side of a single semiconductor substrate of the first conductivity type. First and second semiconductor regions of second conductivity type of opposite conductivity type, and third of second conductivity type formed on the other surface side of the semiconductor substrate.
A semiconductor element having a semiconductor region and an insulating region extending from the one surface side of the semiconductor substrate between the first and second semiconductor regions to the third semiconductor region, and separating the semiconductor element from the first lead frame. Are placed on these lead frames so as to bridge the second lead frame that is arranged so as to bridge the first semiconductor region to the first lead frame, and the second semiconductor region is connected to the first lead region. A bidirectional surface-mounting semiconductor device, characterized in that it is connected to a second lead frame independent of one lead frame, and the whole except a part of these lead frames is sealed and integrated with resin. Is provided.

According to a third aspect of the invention, in order to solve the above problems, a first semiconductor region of a first conductivity type and a first semiconductor region are provided.
A second semiconductor region having a second conductivity type opposite to the first conductivity type, and the first semiconductor region from the one surface side of the second semiconductor region.
A semiconductor element having an insulating region extending to the semiconductor region of the first lead frame and a second lead frame arranged apart from the first lead frame are mounted on the lead frames so as to bridge the first lead frame and the second lead frame. One of the second semiconductor regions electrically insulated from each other is connected to the first lead frame, and the other of the second semiconductor regions is formed into a second lead frame independent of the first lead frame. The present invention provides a bidirectional surface-mount type semiconductor device, which is connected to and integrated with a whole of the lead frame except a part thereof, which is sealed with resin.

According to a fourth aspect of the invention, in order to solve the above problems, a first semiconductor region of a first conductivity type and a first conductivity type formed on both sides of the first semiconductor region. Second and third semiconductor regions of a second conductivity type having a conductivity type opposite to that;
From the one surface side of the second conductivity type semiconductor region,
A semiconductor element having an insulating region extending through the semiconductor region to the third semiconductor region is mounted on the lead frames so as to bridge the first lead frame and the second lead frame arranged apart from the first lead frame. One of the second semiconductor regions electrically isolated from the insulating region is connected to the first lead frame, and the other of the second semiconductor regions is independent of the first lead frame. The present invention provides a bidirectional surface-mount type semiconductor device which is connected to two lead frames, and the whole of the lead frames except for a part thereof is sealed with a resin and integrated.

According to a fifth aspect of the present invention, in order to solve the above-mentioned problems, the first conductivity type is formed on one surface side of a single semiconductor substrate of the first conductivity type and is separated from each other. A semiconductor block in which a plurality of semiconductor elements having first and second semiconductor regions of a second conductivity type of opposite conductivity type are connected in series,
A first lead frame and a second lead frame spaced apart from the first lead frame
Are placed on these lead frames so as to bridge the lead frames of the above, and the first outermost semiconductor region is connected to the first lead frame, and the second semiconductor region is connected to the first lead region. And a second lead frame independent of the lead frame, and the whole of the lead frame except a part of the lead frame is sealed with a resin and integrated, and a bidirectional surface mount type semiconductor device is provided. It is provided.

According to a sixth aspect of the present invention, in order to solve the above problems, a conductivity type opposite to the first conductivity type is formed on one surface side of a single semiconductor substrate of the first conductivity type. Second conductivity type first semiconductor region, and a second conductivity type second semiconductor region formed on the other surface side of the semiconductor substrate,
A semiconductor block having a plurality of semiconductor elements connected in series and having an insulating region formed on the semiconductor substrate for electrically insulating the first semiconductor region and the second semiconductor region is connected to a first lead frame. And a second lead frame arranged apart from the first lead frame are mounted on these lead frames so as to bridge them, and the outermost first semiconductor region on one side is connected to the first lead frame and One surface of the outermost semiconductor substrate is connected to a second lead frame independent of the first lead frame, and the other surface of the other outermost semiconductor substrate and its second semiconductor region are connected. The present invention provides a unidirectional surface-mounting type semiconductor device, characterized in that the whole of the lead frame except for a part thereof is sealed with resin and integrated.

According to a seventh aspect of the invention, in order to solve the above problems, a conductivity type opposite to the first conductivity type is formed on one surface side of a single semiconductor substrate of the first conductivity type. Second conductivity type first semiconductor region, and a second conductivity type second semiconductor region formed on the other surface side of the semiconductor substrate,
A semiconductor block having a plurality of semiconductor elements connected in series and having an insulating region formed on the semiconductor substrate for electrically insulating the first semiconductor region and the second semiconductor region is connected to a first lead frame. And a second lead frame arranged apart from the first lead frame are mounted on these lead frames so as to bridge them, and the outermost first semiconductor region on one side is connected to the first lead frame and One surface of the outermost semiconductor substrate is connected to a second lead frame independent of the first lead frame, and the other surface of the other outermost semiconductor substrate and its second semiconductor region are connected. The present invention provides a unidirectional surface-mounting type semiconductor device, characterized in that the whole of the lead frame except for a part thereof is sealed with resin and integrated.

In order to solve the above problems, a reinforcing member is provided on the outermost surface of the semiconductor element surface opposite to the surface connected to the first and second lead frames. The surface-mounted semiconductor device according to any one of claims 1 to 7, wherein the surface-mounted semiconductor device is fixed.

[0014]

FIG. 1 is a diagram for explaining a first embodiment of the present invention. In the figure, the same symbols as those shown in FIG. 9 indicate members corresponding to the members in FIG. In FIG. 1, a semiconductor element 1 is a single semiconductor substrate 1a of N conductivity type.
Two P-conductivity-type semiconductor regions 1b, 1 formed on one surface of the semiconductor substrate 1a and separated from each other by a conventional planar technique.
with b '. These P-conductivity type semiconductor regions 1b, 1
The b'is formed with the N-conductivity type semiconductor substrate 1a and a PN junction having a guard ring structure. These two PN junctions are connected in series in opposite directions through the semiconductor substrate 1a, and when a voltage exceeding the reverse withstand voltage of the PN junction is applied regardless of the polarity of the voltage, the PN junction causes an avalanche or Zener phenomenon, The first and second lead frames 3,
The voltage of 3'is limited to a certain value or less.

Ohmic contacts are formed in the semiconductor regions 1b and 1b ', respectively, so that the semiconductor element 1 bridges the first and second lead frames 3 and 3'having the same structure. 3, 3 ', and the relatively thick solder layers 2, 2'
It is connected to the second lead frames 3, 3 '. Here, it is preferable that the distance between the semiconductor regions 1b and 1b ′ is equal to or larger than the distance X between the tip surfaces of the first and second lead frames 3 and 3 ′. Further, the N-conductivity type semiconductor substrate 1a between the semiconductor regions 1b and 1b ′ should not be short-circuited by both solder layers 2 and 2 ′, but in the planar semiconductor element 1, the electrode films of the semiconductor regions 1b and 1b ′ are formed. Except for (not shown), it is covered with an insulating film (not shown) such as a dioxide film and does not spread on the surface of the semiconductor element 1 between the lead frames 3 and 3 '. Finally, as shown by the chain line, the whole of the lead frames 3 and 3 ', except for a part thereof, is sealed with an insulating resin to form a resin mold portion 6, which is integrated to obtain a bidirectional surface mount semiconductor device. .

Here, the lead frames 3 and 3'are of the same size as the areas of the semiconductor regions 1b and 1b '(actually a little larger because the field plate extends from the ohmic contact) and higher than the other portions. It has mounting parts 3a and 3'a. Therefore, the solder layer 2,
Since 2'does not extend to the surface of the semiconductor element 1 which is detached from the mounting portions 3a, 3'a of the lead frames 3, 3 ', the insulating film on the surface of the semiconductor element 1 is not destroyed, so that the PN junction is short-circuited There is also no. In this semiconductor element 1, a semiconductor substrate having a PN junction is not cut as an individual diode chip, and two PN junctions are combined with each other to form one diode chip.
It can be easily manufactured by cutting in parallel as a set. According to this surface-mounting type semiconductor device, a connection conductor plate for connecting between diode chips as in the prior art is not required, and accordingly, the soldering process is not required and the thickness can be reduced.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the lead frames 3, 3'having a flat upper surface on which a part of the semiconductor element 1 is mounted
Therefore, the semiconductor element 1 is connected to the lead frames 3, 3'through the metal disks 7, 7'having a thickness of 0.1 to 0.2 mm and having the same area as that of the semiconductor regions 1b and 1b '. Connected to. According to this structure, the distance between the lower surface of the semiconductor element 1 and the lead frames 3 and 3'is increased, so that the solder layers 2 and 2'do not unnecessarily spread on the lower surface of the semiconductor element 1. Also, the disks 7, 7 '
As a semiconductor disc of any conductivity type having a sufficiently high impurity concentration or a metal desk of molybdenum or tungsten having a semiconductor expansion coefficient close to that of the semiconductor element 1 and the lead frames 3 and 3 ', It is possible to provide a surface-mount type semiconductor device that is hardly affected by the adverse effect. The semiconductor element 1 has a structure similar to that shown in FIG.

Next, a third embodiment of the present invention will be described with reference to FIG. In this embodiment, the semiconductor element 1 having a three-layer structure formed by using the planar technique is used. The semiconductor element 1 has a common third semiconductor region 1c formed by using a planar technique on the surface opposite to the semiconductor regions 1b and 1b 'formed as described above. The semiconductor region 1c has the same conductivity type as the semiconductor regions 1b and 1b '. A groove reaching the common third semiconductor region 1c is formed in a portion of the semiconductor substrate 1a of the semiconductor element 1 between the semiconductor regions 1b and 1b ', and the insulating region 1 is filled with glass or the like.
By providing d, the semiconductor regions 1b and 1b 'are separated.

Therefore, according to this semiconductor structure, two PN junctions having different polarities are formed in series between the semiconductor regions 1b and 1b ', so that a total of four PN junctions are formed in series. Can obtain a bidirectional surface mount semiconductor varistor having a high break voltage. The lead frames 3 and 3'and the fixing structure thereof are the same as those shown in FIG. 1 or FIG.

Next, a fourth embodiment of the present invention will be described with reference to FIG. 4. In this embodiment, a semiconductor device 1 having a PN junction having a mesa structure is used. The semiconductor element 1 includes an insulating region 1d formed by filling a groove formed so as to reach from the P conductive type semiconductor region 1B to the N conductive type semiconductor region 1A with the above-described insulating material. The insulating region 1d divides the PN junction into left and right in FIG. 4, and the left and right PN junctions are connected back to back in series by the P-conductivity type semiconductor region 1A. The exposed surface of the PN junction is covered with a normal surface protective agent 8. The other parts are the same as those in the above-mentioned embodiment, and the description thereof will be omitted.

Next, a fifth embodiment of the present invention will be described with reference to FIG. 5. This embodiment corresponds to the planar type three-layer semiconductor device shown in FIG. 3 and has a mesa structure.
The layer semiconductor element 1 is used. The semiconductor element 1 is formed by filling a groove formed so as to reach from the P-conductivity type semiconductor region 1B through the N-conductivity type semiconductor region 1A to the P-conductivity type semiconductor region 1B 'with the above-described insulator. The insulating region 1d is provided. By this insulating region 1d, two PN junctions are divided into left and right in FIG. 5, and the four PN junctions on the left and right are N conductive type semiconductor regions 1B '.
Are connected in series back to back. The semiconductor element 1 is formed on the surface of the N-conductivity type semiconductor region 1B ′ located on the outermost side.
A reinforcing member 8 such as a metal plate, a semiconductor plate or an electrically insulating plate for mechanically reinforcing the is fixed.

For example, the reinforcing member 8 is 0.1 to 0.2.
In the case of a glass plate having a size of about mm, a large-area semiconductor plate on which impurities are diffused in a predetermined pattern is adhered to the large-area glass plate with an adhesive, and then a predetermined portion of the large-area semiconductor plate is attached. Grooves may be formed in the groove, the grooves may be filled with an insulating material, and then cut into individual pieces. In this case, the adhesive may be insulating. However, when the reinforcing member 8 is made of one conductive type semiconductor plate having a high impurity concentration, or a metal plate which can be easily cut, it is preferable to use a conductive adhesive or solder in order to use these as electrodes. .

Such a reinforcing member, particularly a reinforcing member made of an electrically insulating material, can be applied to the embodiment shown in FIGS. 1 to 4 as it is, and even when a reinforcing member made of a conductive material is used, it is partially used. The same can be applied by forming an insulating film. Furthermore, it goes without saying that the present invention can be similarly applied to any of the embodiments described later.

Next, a sixth embodiment of the present invention will be described with reference to FIG. 6. In this embodiment, N between the P-conductivity type semiconductor regions 1b and 1b 'of each of the planar type semiconductor elements as described in FIG. Semiconductor elements 1 and 1 ′ each having an insulating region 1d formed of a P-conductivity type semiconductor region in the conductivity type semiconductor region 1a are connected in series. The semiconductor elements 1, 1'are connected via the metal disks 7, 7'and a solder layer. The semiconductor elements 1 and 1'are respectively separated by an insulating region 1d,
The semiconductor element 1'is divided into right and left diode elements, and the semiconductor element 1'is divided into left and right N conductive type semiconductor regions 1a.
Are connected by a metal film 10 formed on the surface by plating or vapor deposition. When it is desired to remove the metal film 10, a semiconductor element in which the insulating region 1d is not formed may be used as the uppermost semiconductor element 1 '.

Next, a seventh embodiment of the present invention will be described with reference to FIG. 7. In this embodiment, the P-conductivity type semiconductor region 1 is formed on both sides of the N-conductivity type semiconductor region 1a by shifting positions.
b, 1b 'and an insulating region 1 for insulating these regions
The semiconductor element 1 having d and is used. Then, on one surface, the N-conductivity type semiconductor region 1a on one side and the P-conductivity type semiconductor region 1b 'on the other side are connected by a metal film 10 formed on the surface by plating or vapor deposition. Therefore, two PN junctions are connected in series with the same polarity between the lead frames 3 and 3 ', and a unidirectional surface mount type semiconductor device can be obtained. Also in this embodiment, at the same level, the P-conduction type semiconductor region 1b on one side of the semiconductor element 1 is provided.
To the lead frame 3 and the N-conductivity type semiconductor region 1a on the other side to the lead frame 3 '. 1
Reference numeral 1 is an insulating film such as a disilicon oxide film.

Next, an eighth embodiment of the present invention will be described with reference to FIG. 8. In this embodiment, semiconductor elements 1, 1 ′ similar to the semiconductor element having the structure shown in FIG. 7 are connected in series. In this embodiment, four PN junctions are connected in series between the lead frames 3 and 3 ′ with the same polarity, and a unidirectional surface mount type semiconductor device having a constant voltage twice as high as that of the embodiment of FIG. Obtainable.

In the above-mentioned embodiments, the case where the common layer of the semiconductor element 1 is the N-conductivity type semiconductor region has been described, but the same applies to the case where the common layer is the P-conductivity type semiconductor region. be able to. Also, it is possible to connect a desired number of semiconductor elements in series or in parallel, if necessary.

[0028]

As described above, according to the present invention, the following effects can be obtained. (1) Since the step of soldering the connecting member is unnecessary, the cost and the number of assembling steps can be reduced. (2) The structure of the assembly jig is simplified. (3) Since the connecting member is unnecessary, the height after assembly is low and the distance to the resin mold portion is long. Therefore, the surface mount semiconductor device can be made thin. (4) Since the reinforcing member is fixed to the semiconductor element, mechanical stress is not applied to the semiconductor element even if external force is applied, and the semiconductor element is not destroyed. (5) Since the lead frame in which the mounting portion having an area substantially equal to the soldering area of the semiconductor element is higher than the other portions is used, a highly reliable surface mounting type semiconductor device can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an embodiment of the present invention.

FIG. 2 is a diagram for explaining another embodiment of the present invention.

FIG. 3 is a diagram for explaining another embodiment of the present invention.

FIG. 4 is a diagram for explaining another embodiment of the present invention.

FIG. 5 is a diagram for explaining another embodiment of the present invention.

FIG. 6 is a diagram for explaining another embodiment of the present invention.

FIG. 7 is a diagram for explaining another embodiment of the present invention.

FIG. 8 is a diagram for explaining another embodiment of the present invention.

FIG. 9 is a diagram for explaining a conventional example.

[Explanation of symbols]

1, 1 '... Semiconductor element 2, 2' ... Solder layer 3, 3 '... Lead frame 6 ... Resin mold part 7, 7' ... Disk 8 ... Surface protective agent 9 ... Reinforcing member 10 ... Metal film 11 ... Insulating layer

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H01L 23/48 F 27/08 331 B 29/861 29/866

Claims (8)

[Claims] 1. A first conductivity type second semiconductor of a conductivity type opposite to the first conductivity type formed separately from each other on one surface side of a single semiconductor substrate of the first conductivity type. A semiconductor element having two semiconductor regions is mounted on these lead frames so as to bridge the first lead frame and a second lead frame arranged apart from the first lead frame, and the first semiconductor region is placed on the first lead region. One lead frame, the second semiconductor region is connected to a second lead frame independent of the first lead frame, and the whole except a part of these lead frames is sealed with resin to be integrated. An interactive bidirectional surface-mount type semiconductor device. 2. A first conductivity type second semiconductor of a conductivity type opposite to the first conductivity type formed separately from each other on one surface side of a single semiconductor substrate of the first conductivity type. Second semiconductor region, a second conductive type third semiconductor region formed on the other surface side of the semiconductor substrate, and one surface side of the semiconductor substrate between the first and second semiconductor regions. A semiconductor element having an insulating region extending from the first lead frame to the third semiconductor region is mounted on these lead frames so as to bridge the first lead frame and the second lead frame spaced apart therefrom. The first semiconductor region is connected to the first lead frame, the second semiconductor region is connected to a second lead frame independent of the first lead frame, and the whole except a part of these lead frames. Is sealed with resin and integrated A bidirectional surface-mount type semiconductor device characterized in that 3. A first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type opposite to the first conductivity type, and a second semiconductor region of the second semiconductor region. A semiconductor element having an insulating region extending from one surface side to the first semiconductor region is formed on the lead frames so as to bridge the first lead frame and the second lead frame arranged apart from the first lead frame. One of the second semiconductor regions that is placed and electrically insulated from each other by the insulating region is connected to a first lead frame, and the other of the second semiconductor regions is connected to the first lead frame. A bidirectional surface-mount type semiconductor device, characterized in that it is connected to an independent second lead frame, and the whole except a part of these lead frames is sealed and integrated with a resin. 4. A first semiconductor region of a first conductivity type and a second semiconductor region of a second conductivity type opposite to the first conductivity type formed on both sides of the first semiconductor region. A semiconductor element having a third semiconductor region and an insulating region extending from one surface side of the second conductivity type semiconductor region to the third semiconductor region through the first semiconductor region, The lead frame and the second lead frame arranged apart from this are placed on these lead frames so as to bridge them,
One of the second semiconductor regions electrically insulated from each other by the insulating region is connected to the first lead frame, and the other of the second semiconductor regions is isolated from the first lead frame. A bidirectional surface-mounting semiconductor device, characterized in that it is connected to a frame, and the entire lead frame is partially sealed with resin and integrated. 5. A first conductivity type second semiconductor of a conductivity type opposite to the first conductivity type formed apart from each other on one surface side of a single semiconductor substrate of the first conductivity type. A semiconductor block in which a plurality of semiconductor elements having two semiconductor regions are connected in series is placed on these lead frames so as to bridge the first lead frame and the second lead frame arranged apart from the first lead frame. , The outermost first semiconductor region is connected to a first lead frame, and the second semiconductor region is connected to a second lead frame independent of the first lead frame. A bidirectional surface-mount type semiconductor device characterized in that the entire frame except a part is sealed with resin and integrated. 6. A second conductivity type opposite to the first conductivity type formed on one surface side of a single semiconductor substrate of the first conductivity type.
Of the first conductivity type semiconductor region, the second conductivity type second semiconductor region formed on the other surface side of the semiconductor substrate, and the first semiconductor region and the second semiconductor region are electrically connected to each other. A semiconductor element having an insulating region formed on the semiconductor substrate to electrically insulate the first lead frame and a second lead frame arranged apart from the first lead frame to these lead frames. Mounting and connecting the first semiconductor region to the first lead frame,
One surface of the semiconductor substrate is connected to a second lead frame independent of the first lead frame, and the other surface of the semiconductor substrate is connected to the second semiconductor region. A unidirectional surface-mounting type semiconductor device, characterized in that the whole except a part is sealed with resin and integrated. 7. A second conductivity type opposite to the first conductivity type formed on one surface side of a single semiconductor substrate of the first conductivity type.
Of the first conductivity type semiconductor region, the second conductivity type second semiconductor region formed on the other surface side of the semiconductor substrate, and the first semiconductor region and the second semiconductor region are electrically connected to each other. A semiconductor block formed by serially connecting a plurality of semiconductor elements each having an insulating region formed on the semiconductor substrate to electrically insulate the first lead frame and a second lead frame arranged apart from the first lead frame. The lead frames are mounted so as to bridge, and the one outermost first semiconductor region is connected to the first lead frame.
One surface of the one outermost semiconductor substrate is connected to a second lead frame that is independent of the first lead frame, and the other surface of the other outermost semiconductor substrate and its second semiconductor A unidirectional surface-mount type semiconductor device, characterized in that it is connected to a region, and the whole of the lead frame except a part thereof is sealed with resin and integrated. 8. The reinforcing member is fixed to the outermost surface of the semiconductor element surface opposite to the surface connected to the first and second lead frames. The surface-mounted semiconductor device according to any one of claims.