JPH02174266A - Multipolar bidirectional semiconductor control device - Google Patents

Abstract

PURPOSE:To reduce the number of elements for constructing a protector, etc., and simplify the process for assembling into a box by unifying a plurality of pnpn-type two-terminal thyristors into one semiconductor chip. CONSTITUTION:A p-type is used as a first conduction type and an n-type as a second conduction type. This device is formed of five layer regions, i.e., a first semiconductor layer P6, and a fourth semiconductor layer P7a, P7b, consisting of n-type semiconductors, and a second semiconductor layer N8ab, a third semiconductor layer N9a, N9b, and a fifth semiconductor layer N10a, N10b, consisting of n-type semiconductors. The semiconductor layer P6 and the semiconductor layer N8ab are shorted by an electrode 26a, the semiconductor layer P7a and the semiconductor layer N10a are shorted by an electrode 27a, and the semiconductor layer P7b and the semiconductor layer N10b are shorted by an electrode 27b. When used as a protector for a communication apparatus, a terminal 28 is connected to the earth 30, a terminal 29a is connected to core line 31a of a communication line, and a terminal 29b is connected to a core line 31b of the communication line. The core lines 31a, 31b are connected to a communication apparatus 32.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multipolar bidirectional semiconductor control element for protecting equipment from abnormal voltages such as lightning surges.

(Prior Art) Conventionally, as this type of bidirectional semiconductor control device, one shown in FIG. 7 is known. This bidirectional semiconductor control element
consists of five layer regions of sequentially adjacent semiconductor layer Nl, semiconductor NP2, semiconductor layer N3, semiconductor layer P4, and semiconductor layer N5, where semiconductor layers Nl, N3, and N5 are n-type semiconductors, and semiconductor layers P2 and P4 are n-type semiconductors. It is a p-type semiconductor. The semiconductor layer Nl and the semiconductor layer P2 at one end are short-circuited by the electrode 2, and the semiconductor layer P4 and the semiconductor layer N5 at the other end are short-circuited by the electrode 3. A terminal 4 is formed on the electrode 2, and a terminal 5 is formed on the electrode 3. Furthermore, as shown in FIG. 8, the voltage-current characteristics of this conventional bidirectional semiconductor control element include a high resistance region 6a, 5b, breakdown regions 7a and 7b having relatively low differential resistance, transition regions 8a and 8b, and low resistance regions lla and llb. Points 9a and 9b in the figure are the breakover N pressure, and points 10a and fob are the holding current.

Next, FIG. 9 shows an example in which a protector for communication relay equipment is constructed using this conventional bidirectional semiconductor control element.

Core wire 14 of the communication line on the side of the inductor transformer 12 of the repeater 11
and the core wire 15, elements 19 and 20 between the core wire 14.15 and the ground 24, and elements 21 and 22 between the core wire 16.17 on the side of the output transformer 13 and the ground 24. , an element 23 is connected between the core wire 16 and the core wire 17, respectively. When a lightning surge is applied, for example, between the core wire 14 and the ground 24, the element 19 turns on and the lightning surge current flows to the ground 24 to protect the repeater 11. Normally, during a lightning strike, Surges of the same voltage are applied between the core wire 14 and the ground 24 and between the core wire 15 and the ground 24 at the same time. At this time, element 19 and element 2
If there is a difference in operating characteristics between ,
The repeater 11 may be damaged. In addition, if an abnormal voltage is applied directly between the core wire 14 and the core wire 15, the core wire 1
Element 19 and element 20 are inserted in series between 4 and core wire 15, and the operating voltage is higher than when elements 19 and 20 are used alone (up to the sum of the breakover voltage of each element). ), the repeater 11 may not be protected.

In order to avoid these problems, it is desirable to use elements 19 and 20 that have the same operating characteristics.
In many cases, an element 18 is inserted between the core wire 15 and the core wire 15.

The above also applies to the output transformer 13, and in this example, four to six bidirectional semiconductor control elements are required.

(Problems to be Solved by the Invention) By the way, in the conventional bidirectional semiconductor control device, when configuring a protector etc. that protects equipment from abnormal voltage, at least one bidirectional Semiconductor control elements must be used.

Furthermore, bidirectional semiconductor control devices may differ in operating characteristics even if they are manufactured in the same lot, so a separate bidirectional semiconductor control device must be added to avoid damage to equipment due to differences in operating characteristics. There must be. Therefore, there is a problem in that a large number of bidirectional semiconductor control elements are required.

(Means for Solving the Problems) In order to solve such problems, the multipolar bidirectional semiconductor control device of the present invention is a bidirectional semiconductor control device consisting of a plurality of pnpn type two-terminal thyristors. , 1st
a first semiconductor layer of a conductivity type; and a second semiconductor of a second conductivity type included in the first semiconductor layer and exposed on one main surface of the first semiconductor layer. a plurality of third semiconductor layers of a second conductivity type formed on the other main surface of the first semiconductor layer and spaced apart from each other; and a plurality of third semiconductor layers formed only on the plurality of second semiconductor layers. a fourth semiconductor layer of a first conductivity type, and each of the plurality of fourth semiconductor layers includes a fourth semiconductor layer that is included in the fourth semiconductor layer and exposed on the external surface of the fourth semiconductor layer. a fifth semiconductor layer of the second conductivity type formed; a single electrode formed by short-circuiting the first semiconductor layer and the second semiconductor layer at their respective external surfaces; The gist includes a plurality of electrodes formed by short-circuiting a fourth semiconductor layer and a fifth semiconductor layer formed on the fourth semiconductor layer in pairs on each external surface. do.

(Function) In the present invention, a plurality of pnpn type two-terminal thyristors are formed adjacent to the same semiconductor substrate to constitute a multipolar bidirectional semiconductor control element. Therefore, each pnpn type two-terminal thyristor has operating characteristics that are very similar to each other.

Furthermore, when constructing a protector or the like, the number of elements used is reduced, which allows for miniaturization and a reduction in the number of terminals.

(Embodiment) FIG. 1 is a sectional view of an embodiment of a multipolar bidirectional semiconductor control element of the present invention.

This multipolar bidirectional semiconductor control element 25 uses p type as the first conductivity type and n type as the second conductivity type. A first semiconductor layer P6 and a fourth semiconductor layer P7a, P7b are made of a p-type semiconductor, and a second semiconductor layer is made of an n-type semiconductor.
It consists of five layer regions: a semiconductor layer N8ab, a third semiconductor layer N9a, N9b, and a fifth semiconductor layer N10a, N10b.

The semiconductor layer P6 and the semiconductor layer N8ab are short-circuited by an electrode 26, the semiconductor layer P7a and the semiconductor layer N10a are short-circuited by an electrode 27a, and the semiconductor layer P7b and the semiconductor layer N10b are short-circuited by an electrode 27b.

FIG. 2 is a wiring diagram of an example in which this multi-polar bidirectional semiconductor control element is used as a protector for communication equipment.

The terminal 2 is connected to the electrode 26 of the multipolar bidirectional semiconductor control element 25.
8. Terminal 29a is attached to electrode 27a, and terminal 2 is attached to electrode 27b.
9b are provided respectively. Terminal 28 to ground 30,
The terminal 29a is connected to the core wire 31a of the communication line, and the terminal 29b is connected to the core wire 31b of the communication line. and core wire 31
a and 31b are connected to the communication device 32.

Next, the operation of this multipolar bidirectional semiconductor control element will be explained. First, this multipolar bidirectional semiconductor control element 25 is separated into a bidirectional semiconductor control element 33a sandwiched between the left half of the electrode 26 in the figure and the electrode 27a, and a bidirectional semiconductor control element 33a sandwiched between the right half of the electrode 26 in the figure and the electrode 27b. The bidirectional semiconductor control element 33b sandwiched by the two elements, and the resistor R consisting of the first semiconductor layer P6 between these elements will be considered. Here, during a lightning strike, if a lightning surge is applied such that, for example, the terminal 28 has a positive potential and the terminal 29a has a negative potential, the voltage-current characteristic shown in FIG. Protect 32. At this time, the resistance value of the resistor R is sufficiently large (element 33
The effect on b is extremely small. That is, element 33a
and element 33b can be considered to be electrically insulated. Therefore, element 33a and element 33b each operate independently. Further, in these elements, the current paths for forward direction operation and reverse direction operation are structurally symmetrical, so that forward direction characteristics and reverse direction characteristics can be easily obtained.

Further, since the elements 33a and 33b constituting the multipolar bidirectional semiconductor control element 25 are formed adjacently on the same semiconductor substrate at the same time, they can have characteristics extremely similar to each other. That is, for the reason stated in the description of the prior art, the voltage generated between the core wires 31a and 31b due to the difference in operating voltage between the elements is extremely low. Therefore, there is no need to provide another bidirectional semiconductor control element between the core wire 31a and the core wire 31b.

Furthermore, FIG. 3 shows an example in which the protector configured using six conventional bidirectional semiconductor control devices shown in FIG. 9 is replaced with one multipolar bidirectional semiconductor control device of the present invention. be.

This multipolar bidirectional semiconductor control element 34 has a structure in which bidirectional semiconductor control elements 33a, 33b, 33c, and 33d are connected via a first semiconductor layer P6 and second semiconductor layers N8ab and N8cd. ing. On the side of the inductance lance 12 of the repeater 11, the electrode 27a of the element 33a is connected to the communication core wire 14 via the terminal 29a, and the electrode 27b of the element 33b is connected to the communication core wire 15 via the terminal 29b. It is connected. On the side of the output transformer 13, the electrode 127c of the element 33c is connected to the communication core wire 17 via the terminal 29c, and the electrode 27d of the element 33d is connected to the communication core wire 16 via the terminal 29d. . Further, the electrode 35 is connected to the ground 24 by a terminal 28. That is, the element 33a connects the core wire 14 and the ground 24.
The element 33b is provided between the core wire 15 and the earth 24, the element 33c is provided between the core wire 17 and the earth 24, and the element 33d is provided between the core wire 16 and the earth 24. This protects the repeater 11, etc. from the abnormal voltage generated. Note that since the element 33a and the element 33b are formed adjacent to each other, their operating characteristics are almost the same. Therefore, the core wire 14
Since the abnormal voltage generated between the core wire 14 and the core wire 15 is small, there is no need to provide another bidirectional semiconductor control element between the core wire 14 and the core wire 15. Similarly, there is no need to provide another bidirectional semiconductor control element between the core wires 16 and 17. In this way, the conventional multi-polar bidirectional semiconductor control element of the present invention can be used to realize one bidirectional semiconductor control element, whereas six bidirectional semiconductor control elements were conventionally required to construct a protector. Therefore, it is possible to downsize the protector, simplify the process of incorporating it into the protector housing,
It is possible to reduce the number of manufacturing steps, such as by omitting the element combination selection process.

FIG. 4 is a sectional view of a multipolar bidirectional semiconductor illumination device of the present invention.

In this way, the first semiconductor layer P6, the second semiconductor layer N8
ab, N8cd, ---1 third semiconductor layer N9a, N9
b, N9c, --1 fourth semiconductor layer P7a, P,
7b, P7c, -=-1 fifth semiconductor layer N10a, Nl
0b, N10c, ... electrodes 36.27a, 27b, 2
Any number of bidirectional semiconductor control elements consisting of 1c, --= may be formed in parallel.

FIGS. 5 and 6 show other embodiments of the multipolar bidirectional semiconductor control device of the present invention. Components that are the same as those in FIGS. 1 and 2 are given the same numbers, and their explanations will be omitted.

In FIG. 5, the positions where the second semiconductor layers N8a, N8b and the fifth semiconductor layers N10a, N10b are provided are different from FIG. 1. It may be formed in this way.

In the first semiconductor layer P6 of FIG. 6, a groove 37 is formed on the surface where the third semiconductor layers N9a and N9b are not formed. With this groove 37, the value of the resistance R shown in the figure can be increased, and the insulation between the elements 33a and 33b can be further improved.

In the above embodiment, a slit may be formed in one or both of the semiconductor layers of the second semiconductor chip 5 from the electrode side in order to increase the holding current.

Furthermore, in the above embodiments, the first conductivity type is n type,
Although p-type is used as the second conductivity type, of course, p-type may be used as the first conductivity type, and n-type may be used as the second conductivity type.

(Effects of the Invention) As explained above, according to the multipolar bidirectional semiconductor control device of the present invention, a plurality of pnpn type two-terminal thyristors are integrated into one semiconductor chip, so that protectors etc. The number of elements to be configured can be reduced, and the number of manufacturing steps can be reduced, such as by simplifying the process of assembling the device into the housing and omitting the process of selecting a combination of elements.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the multi-polar bidirectional semiconductor control device of the present invention, and FIG. 2 is a cross-sectional view showing an example of using the multi-polar bi-directional semiconductor control device of the present invention as a protector for communication equipment. Connection diagram, FIG. 3 is a connection diagram when the multi-pole bidirectional semiconductor control element of this invention is used as a protector of a repeater for communication equipment, and FIG. 4 is a wiring diagram of the multi-pole bi-directional semiconductor control element of this invention. 5 and 6 are cross-sectional views showing other embodiments of the multipolar bidirectional semiconductor control element of the present invention, and FIG. 7 is a cross-sectional view showing a conventional bidirectional semiconductor control element. FIG. 8 is a graph showing voltage-current characteristics of a conventional bidirectional semiconductor control element, and FIG. 9 is a wiring diagram when the conventional bidirectional semiconductor control element is used as a protector for a repeater for communication equipment. P6...first semiconductor layer, N8ab, , N8cd, N
8a, N8b---second semiconductor layer, N9a, N9b,
N9cm-・Third semiconductor layer, P7a2, P7b, Pl
cm...Fourth semiconductor layer, N10a, N10b, Nl
0c =...Fifth semiconductor layer, 26.27a, 27b
, 27c, 27d --- Electrode. 7a 7b Figure 1 Patent applicant: Agent of Hakusan Seisakusho Co., Ltd.
Patent Attorney Yoshi 1) Yoshiharu Figure 2 Figure 5 Figure 6

Claims (1)

[Claims] A bidirectional semiconductor control device comprising a plurality of pnpn type two-terminal thyristors, comprising: a first semiconductor layer having a first conductivity type; and a first semiconductor layer included in the first semiconductor layer; A second layer of the second conductivity type formed exposed on one main surface of the layer.
a plurality of third semiconductor layers of the second conductivity type formed on the other main surface of the first semiconductor layer and spaced apart from each other; and on the plurality of third semiconductor layers. a fourth semiconductor layer of the first conductivity type that is formed only in the fourth semiconductor layer; a single electrode formed by short-circuiting the first semiconductor layer and the second semiconductor layer at their respective external surfaces; A plurality of electrodes are formed by short-circuiting the fourth semiconductor layer and the fifth semiconductor layer formed on the fourth semiconductor layer in pairs on each external surface. Features a multi-polar bidirectional semiconductor control element.