JPH0469434B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention improves the amplification gate structure of a conventional optical trigger thyristor, and provides an optical trigger thyristor that dramatically increases the optical trigger sensitivity of the conventional optical trigger thyristor. Regarding this, it is used as a switching element not only in small to medium power converters but also in high power converters.

[Conventional technology]

Traditionally, triggering thyristors with light has been widely used, and LASCR, Light Activated
It is a well-known fact that this technology is implemented under names such as Thyristor and Photothyristor.

FIG. 9 shows an example of the structure of a conventional optically triggered thyristor. It has a structure that integrates amplification thyristors. In order for light to penetrate inside the base,
In order to increase the photosensitivity of the amplifying thyristor, the p-base layer is dug into the portion that is irradiated with light, making it thinner. Furthermore, in order to improve the dv/dt tolerance, the cathode and base of the amplifying thyristor and the main thyristor are generally short-circuited. n cathode region 811, p base layer 803,
The n base layer 802 and the p anode layer 801 form an auxiliary thyristor for the amplification gate with an npnp four-layer structure, while the n cathode layer 804, the p base layer 803, the n base layer 802, and the p anode layer A thyristor is formed.
The n-cathode 811 of the auxiliary thyristor and the p-base layer 803 are short-circuited by an electrode 833, and the n-cathode 804 of the main thyristor and the p-base layer 803 are short-circuited by an electrode 832. Incident light 861 introduced through an optical fiber or the like passes through the thin n cathode layer 811 and generates electron-hole pairs in a depletion layer formed at the junction between the p base 803 and the n base 802. The generated holes flow through the base resistance portion 850 in the thin p base layer, while the generated electrons flow between the n base 802 and the p anode 8.
01 and causes hole injection from the p anode 801. A current due to the injected holes and holes generated by light flows through the base resistance 850 in the thin p base layer, and the base potential of the auxiliary thyristor rises.
When the turn-on threshold is reached, the auxiliary thyristor turns on. In the on state, the hole current flows through the n-cathode 811 through the electrode 833 and then through the base resistance 85 in the p-base layer 803 of the main thyristor.
4 will flow. Electron current is n cathode 8
11, flows through the p base made thinner by diffusion, flows through the strong electric field portion of the p base 803 and n base 802, accumulates at the junction between the n base 802 and the p anode 801, and further promotes hole injection from the p anode 801. At the same time, it flows out to the p anode electrode 831. When the auxiliary thyristor is turned on, an overwhelming number of hole currents are injected from the p-anode 801 toward the p-base 803, so the base resistance 854 in the base layer 803 of the main thyristor is When the hole current flows and the base potential of the main thyristor exceeds the turn-on threshold value, the main thyristor turns on. When the main thyristor is on, hole current flows through the n-cathode 804 and continues to be absorbed by the cathode electrode 832, and electron current flows from the n-cathode 804 through the p-base 803 by diffusion and drifts through the n-base layer 802. It flows through the p anode 801 and is absorbed by the anode electrode 831. 851 represents an anode terminal, and 852 represents a cathode terminal of the main thyristor.

[Problem to be solved by the invention]

As mentioned above, the conventional optically triggered thyristor is
An auxiliary amplification thyristor is used as a trigger mechanism, and the auxiliary amplification thyristor has a bipolar base structure. The direct current optical amplification factor (current amplification factor) of a bipolar base structure based on a uniform base can be expressed by the following equation using an approximation that the incident light intensity is small.

β＝D _o L _p n _e /D _p W _b P _b ...(1) In equation (1), D _o and D _p are the electron and hole diffusion constants, L _p is the hole diffusion distance, and W _b is the base width,
n _e is the impurity density at the emitter, and p _b is the impurity density at the base. In reality, the value of β is approximately 10 ² to 10 ³ at most. Therefore, triggering the amplifying thyristor with light requires considerably strong optical power. As described above, the conventional optical trigger thyristor has a problem in that the light sensitivity of the amplification gate is low, so a very high output light source is required as the trigger light source. Therefore, there is a method of thinning the base layer of the auxiliary amplification thyristor as shown in FIG.
Alternatively, attempts have been made to increase the optical amplification degree by connecting multiple stages of elaborate auxiliary thyristors to such a base layer, but this has resulted in a complex structure.

[Means to solve the problem]

The present invention provides a photo-triggered thyristor that applies a static induction transistor (SIT) gate structure as an amplification gate to improve the photosensitivity of the conventional photo-triggered thyristor.

In the SIT gate structure, the potential barrier when holes in the gate pass through to the source side is larger than the potential barrier crossed when electrons on the source side flow to the drain, so holes are accumulated in the gate region. Therefore, the current amplification factor β becomes very large. Moreover, the smaller the input light intensity is, the larger it is, and the maximum value of the DC optical amplification of the SIT gate structure corresponds to the limit where the incident light intensity is equivalent to the dark hole current, and G _nax = n _S (D _o /W _G )/P _G (D _P /L _P )・expg/KT (+V _bi
Gs −V biG ^* ) ...(2) In equation (2), W _G is the effective width of the gate potential barrier, n _S
is the impurity density of the source, p _G is the impurity density of the gate, k is Boltzmann's constant, T is the absolute temperature, q is the unit charge, and V _biGS is the gate-source value that must be crossed when holes in the gate region escape to the source side. The potential barrier height between them, V biG ^* S, is the true potential barrier height between the gate point G ^* and the source that must be overcome when electrons on the source side flow to the drain. The true gate is unique to the SIT gate structure and is the saddle point of the potential developed in the channel. As is clear from equation (2), between the gate and source and the true gate point G ^*
The difference in the potential barrier between the source and the source greatly affects the optical amplification (current amplification factor). Therefore, the optical amplification factor (current amplification factor) of the SIT gate structure is lower than that of the bipolar base structure mentioned above. degree (current amplification factor)
becomes much larger than As experimental results, values exceeding 10 ⁸ were obtained for extremely weak light of 10 ^-10 (W/cm ² ), and if the SIT gate structure is applied to the amplification gate of a conventional optical trigger thyristor, the optical trigger sensitivity can be increased. A dramatically improved optically triggered thyristor that can be driven at high speed by weak light can be realized. That is, the trigger sensitivity of the conventional optical trigger thyristor is improved by integrating the electrostatic induction thyristor with the SIT gate structure and the main thyristor.

〔Example〕

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

FIG. 1 shows an embodiment of the invention shown in FIG. 1st
The main feature of the illustrated embodiment is that the amplification gate structure of the optically triggered thyristor is composed of a buried gate type SI thyristor.

In FIG. 1, the main thyristor is composed of a p ⁺ anode region 101, an n ^- base region 102, a p base region 103, an n ⁺ cathode region 104, an n ⁺ high impurity density region 105, and a p ⁺ anode region An anode electrode 131 is provided on the surface exposed portion of the n ⁺ cathode region 10.
A cathode electrode 132 is provided on the surface exposed portion of the n + cathode region 104 and the p base region 103 , and the n ⁺ cathode region 104 and the p base region 103 are electrically connected in common by the cathode electrode 132 . This is to increase the dv/dt tolerance of the main thyristor portion. In addition, n ⁺ high impurity density region 105
is provided to improve the current amplification factor of the main thyristor and the auxiliary amplifying thyristor. n ⁺
A structure in which the high impurity density region 105 is not specially provided may be used. The buried gate type SI thyristor for amplification has a p ⁺ anode region 101', an n ^- low impurity density region 102', and an n ⁺ high impurity density second gate region 105', which are formed in the common region with the main thyristor part. , n ⁺ cathode region 111 and p ⁺
The first gate region 112 is composed of n ⁺
Cathode region 111 and p ⁺ first gate region 112
A cathode electrode 133 is provided on the surface exposed portion of each
and a first gate electrode 134 are provided. Between the first gate and cathode of the SI thyristor for amplification,
It is etched into a bevel shape to improve the breakdown voltage and also serves as a light introduction area.
The trigger incident light LT161 is refracted and enters from the bevel position as shown in FIG.

The first gate 112 of the amplifying SI thyristor is connected to a reverse bias V _GK 153 via a resistor R _GK 154 . The resistor R _GK 154 controls the optical amplification factor (current amplification factor) of the amplifying SI thyristor. Further, although V _GK 153 is determined by the characteristics of the amplifying SI thyristor, the dv/dt tolerance is improved by reverse biasing between the first gate and the cathode. Furthermore, the bias circuit of the p ⁺ first gate region 112 of the amplifying SI thyristor is not limited to the example shown in _FIG . Sometimes they are connected. The n ⁺ cathode region 111 of the amplifying SI thyristor and the cathode region 104 of the main thyristor are electrically connected in common.

The operation is explained as follows. trigger light
As for the wavelength of LT161, it is preferable to choose a wavelength that allows the light to penetrate through a relatively long distance. For example, the wavelength obtained by a GaAs infrared light emitting diode may be sufficient.

p ⁺ first gate region 112 and p ⁺ anode region 1
It is desirable that electron-hole pairs be efficiently generated within the depletion layer formed in the n ^- region 102' between 01' and 01'. The generated holes are accumulated in the p ⁺ first gate region 112 of the auxiliary SI thyristor and are formed in the n ^- layer 102' sandwiched between the p ⁺ first gate 112 near the n ⁺ cathode region 111. The height of the potential barrier is lowered by the electrostatic induction effect accompanying the potential change of the first gate region 112. Along with this, electrons in the n ⁺ cathode region 111 are injected into the n ^- layer 102', and as the potential barrier height decreases, the amount of injection increases, and the second gate becomes
It accumulates at the n ⁺ region 105' or, if the n ⁺ region 105' does not exist, at the n ^- 102' p ⁺ 101' junction interface. When the n ⁺ region 105' does not exist, the amplifying SI thyristor is a single gate type SI thyristor, and when the n ⁺ region 105' exists, it is a double gate type SI thyristor. In the case of a single gate type SI thyristor, the p ⁺ region 112 is simply called the gate region. The accumulated electrons are those generated by light and those injected from the n ⁺ cathode. The maximum value of optical amplification regarding injection of electrons from the n ⁺ cathode 111 is given by (2) above.
Since it is expressed by the formula, it is very large, and it has the characteristic that the weaker the light intensity, the larger it becomes. Similarly, the maximum value of the optical amplification accompanying the injection of holes from the p ⁺ anode 101' which is multiplied by the n ⁺ second gate 105' is approximately expressed by the same equation as equation (2). It will be done. To form such a SIT gate structure, the n ^- layer 10 between the p ⁺ first gate 112 is
2' is almost depleted and a potential barrier is formed, the height of which is higher than that of the first gate 112 and the anode 1.
n ^- layer 102' and
It is only necessary that the impurity density and spacing of the p ⁺ gate are selected. The same applies to the second gate side formed by the n ⁺ second gate 105' and the p ⁺ anode 101'. The n ⁺ second gate 105' has such a SIT gate structure and has the function of increasing hole injection efficiency from the p ⁺ anode region 101, but structurally,
This device structure is more complicated than the device structure in which the n ⁺ 105 region does not exist. Another major feature of SI thyristors is that the turn-on threshold can be lower than that of ordinary four-layer thyristors. This is also due to the SIT gate structure. 0.8eV for conventional thyristor
0.4eV~ for SI thyristors, compared to about 0.4eV
0.75eV and various p ⁺ variations can be made by changing the spacing between the first gates 112 and the impurity density.

The turn-on of an SI thyristor can therefore be triggered with a lower intensity of light compared to a conventional thyristor. 1st gate 1 for SI thyristor
The capacitor around 12 is smaller than that of the base of a conventional thyristor with a bipolar base. Furthermore, since the first gate 112 is a high impurity density region, there is no base resistance and the internal resistance of the gate is small. In particular, the turn-on delay time that determines the turn-on speed is p ⁺ the turn-on threshold determined by the time it takes for the potential of the first gate 112 to rise and reach the turn-on threshold voltage to be small. , it becomes shorter because the capacitance of the gate is small. Also, by connecting an external resistor R _GK 154 to the gate, the reverse bias voltage V _GK 1
It is also possible to control the optical trigger sensitivity and response time by adding 53 or the like. Turn-on of the main thyristor occurs as follows. The amount of holes injected from the p ⁺ anode regions 101' and 101 increases and the p base region 1 of the main thyristor
However, when the potential of the p base 103 exceeds the turn-on threshold due to the base resistance drop in the base layer 103, the main thyristor turns on, and the n ⁺
Electrons from the cathode 104 diffuse through the p base layer 103 and drift through the n ^- layer 102 to form the n ⁺ second gate region 105 or n ^- 102p ⁺ 101
is accumulated at the interface. In the ON state of the main thyristor, holes flowing into the p base layer 103 continue to be absorbed by the cathode electrode 132 through the n ⁺ cathode 104, and electron current is absorbed by the p ⁺ anode electrode 131 through the p ⁺ anode region 101. continues to be.
Therefore, in order to turn on the main thyristor quickly, it is necessary to increase the amount of holes injected from the p ⁺ anode 101, and for this purpose, it is necessary that the n ⁺ second gate 105 has a SIT gate structure. It is clear that it is preferable that the first gate of the auxiliary thyristor, p ⁺ gate 112, also has a SIT gate structure. That is, in the embodiment shown in FIG.
Since the thyristor is used as an auxiliary thyristor for amplification, the optical trigger sensitivity is extremely high.
The dv/dt tolerance is also increased by inserting a reverse bias V _GK between the first gate and cathode of the auxiliary thyristor section.

FIG. 2 shows a second embodiment of the invention. The main features of the second embodiment are that the amplification gate structure of the optical trigger thyristor is composed of a buried gate type SI thyristor, and that the n ⁺ cathode region 204, p base region 203 of the main thyristor and the auxiliary SI for amplification are
The n ⁺ cathode region 211 and the p ⁺ gate region of the thyristor are electrically shared by the same cathode electrode 232, and furthermore, the part into which light is introduced is the n ⁺ cathode region of the amplification SI thyristor, and that region is This allows light to easily penetrate without providing electrodes. The operation is basically the same as the embodiment shown in FIG. 1, but the auxiliary SI thyristor must be of a normally-off type.

Each part will be briefly explained. The auxiliary thyristor part includes an n ⁺ cathode 211, a p ⁺ first gate 212,
It is formed of a high resistance n ^- layer 202, an n ⁺ second gate 205, and a p ⁺ anode 201. 2nd gate 20
A structure in which 5 does not exist may be used. In this case, p ⁺ region 212 is simply called a gate region, similar to FIG. 1. The main thyristor part is n ⁺ cathode 20
4, p base 203, n ^- high resistance layer 202, second
It is formed by a gate 205 (n ⁺ ) and a p ⁺ anode 201. A region 232 is a cathode electrode, a region 231 is an anode electrode, and trigger light is irradiated from above the antireflection film 242 through a light transmission medium LT261 such as an optical fiber. A normal white light lamp can be used as a trigger light source, but GaAs light has a relatively long penetration distance due to its wavelength.
Infrared light from light emitting diodes shows good characteristics. The embodiment of FIG. 2 has n ⁺ cathode 2 as described above.
11 and p ⁺ first gate 212 and p base 20
3. The feature is that each part of the n ⁺ cathode 204 is a common area.

FIG. 3 shows a third embodiment of the present invention. The main features of the embodiment shown in Fig. 3 are that the amplification gate structure of the optical trigger thyristor is composed of a planar gate type SI thyristor, and that the light introduction part is a region dug above the step. This improves the efficiency of light penetration. The basic operation is similar to the embodiment shown in FIG.

Each part will be explained. n ⁺ cathode region 311, p ⁺
First gate region 312, n ^- high resistance layer 302, n ⁺
Second gate region 305, p ⁺ anode region 301
The auxiliary SI thyristor is formed by
A main thyristor is formed by the n ⁺ cathode 304, the p base 303, the n ^- high resistance layer 302, the n ⁺ second gate 305, and the p ⁺ anode 301.
333 and 334 indicate the cathode and gate electrodes of the auxiliary SI thyristor. The incident light is directed onto the auxiliary thyristor portion by means of a light transmission medium LT361 such as an optical fiber. 334, 33 as electrode material
3 is a transparent electrode. Cathode electrode 332 of the main thyristor and cathode electrode 33 of the auxiliary SI thyristor
3 is electrically common, and a resistor R _GK is connected between the first gate 312 and the cathode 311 of the auxiliary thyristor.
A reverse gate bias V _GK 353 is applied via 354 . The region 368 is made of an insulating material such as polyimide resin. Region 331 indicates an anode electrode,
351 and 352 indicate an anode terminal and a cathode terminal, respectively.

A fourth embodiment of the present invention shown in FIG. 4 has a planar gate type SI thyristor as the amplification gate structure,
This is an example of a structure in which light is introduced from an etched portion on a bevel.

Explain each part. Auxiliary SI thyristor n ⁺
It is formed of a cathode 411, a p ⁺ first gate 412, an n ^- high resistance layer 402, an n ⁺ second gate 405, and a p ⁺ anode 401, and the main thyristor is an n ⁺ cathode 404, a p base 403, and an n ^- high resistance layer. 4
02, n ⁺ second gate 405 and p ⁺ anode 40
It is formed from 1. Reference numeral 432 designates a cathode electrode of the main thyristor, which is electrically common to the cathode electrode 433 of the auxiliary SI thyristor, and is connected to the gate electrode 434 of the auxiliary SI thyristor and the cathode electrode 433 of the auxiliary SI thyristor.
Reverse gate bias via resistor R _GK 454 between
V _GK 453 is applied. The region 431 is an anode electrode, and 451 and 452 are an anode terminal and a cathode terminal. Trigger incident light LT4
No. 61 enters the auxiliary thyristor through a mesa-etched surface dug into the periphery of the auxiliary thyristor.

FIG. 5 shows a fifth embodiment of the present invention, in which the amplification gate structure is composed of a step gate type SI thyristor, and light is introduced from an etched portion on the step.

Explain each part. The auxiliary SI thyristor is formed of an n ⁺ cathode 511, a p ⁺ first gate 512, an n ^- high resistance layer 502, an n ⁺ second gate 505 and a p ⁺ anode 501, and the main thyristor is an n ⁺
Cathode 504, p base 503, n ^- high resistance layer 502, n ⁺ second gate 505 and p ⁺ anode 5
It is formed from 01. The cathode electrode 532 of the main thyristor is electrically common to the cathode electrode 533 of the auxiliary SI thyristor, and the p ⁺ gate electrode 534 of the auxiliary SI thyristor is connected to the cathode electrode 533 of the auxiliary SI thyristor.
33, a reverse bias voltage V _GK 553 is applied via a resistor R _GK 554. 531 represents an anode electrode, and 551 and 552 represent an anode terminal and a cathode terminal, respectively. Trigger incident light TL561 mainly enters the high resistance layer region 5 from the end face between the gate and cathode electrodes of the auxiliary thyristor.
It is intruding into 02 while being refracted. The region 580 is made of an insulating material such as polyimide resin.

In the embodiment of FIG. 5, the area into which light enters is
There is also a method of introducing light by forming not only the etched portion on the bevel but also the cathode electrode 533 and the gate electrode 534 with transparent electrodes.

FIG. 6 shows a sixth embodiment of the present invention. The main feature of the embodiment shown in FIG. 6 is that the amplification gate structure is composed of MIS gate type SI thyristors.
High-speed optical triggering can be achieved by using a high-speed MIS type SI thyristor. Explain each part. Auxiliary SI
The first gate portion of the thyristor is the gate electrode 63
4. It is formed of an MIS gate region consisting of an insulator 680 and a p ^- layer 612. Auxiliary SI thyristor
n ⁺ region 611, high resistance p ^- region 612, high resistance p ^-
or an ^n- or i-layer 602, ^{an n +} second gate 605, and ^a p ⁺ anode 601;
It is formed from an n ⁺ second gate 605 and a p ⁺ anode 601. High resistance p ^- layer 6 of auxiliary thyristor
In 12, p ⁺ region 613 is diffused,
This region 613 limits the channel thickness (in the MIS direction) of the p ^- layer, and at the same time, the trigger incident light 690 allows the p ^- layer 612 and the high resistance layer 6
The electrode 633 serves as an accumulation region for holes generated in the electrode 633 and a region for the accumulated holes to flow out through the electrode 633. Main thyristor cathode electrode 63
2 is electrically shared with the cathode electrode 633 of the auxiliary SI thyristor, and a reverse gate bias voltage V _GK 653 is applied between the gate electrode 634 and the cathode electrode 633 of the auxiliary SI thyristor. The region 692 is made of an insulating material such as polyimide resin. 651 and 652 are anode terminals, respectively;
The cathode terminal is shown.

〔Effect of the invention〕

Regarding the embodiments of the present invention described above, the experimental results of the direct current optical amplification factor (current amplification factor) of the SIT gate structure will be explained while comparing them with the experimental results of the bipolar base structure.

FIG. 7 shows the dependence of the DC optical amplification degree G of SIPT on the incident light intensity P _i . The drain bias voltage V _D is used as a parameter, and at the same time, the change in the gate potential of SIPT ΔV _G is shown.

FIG. 8 shows the dependence of the DC optical amplification G of a bipolar phototransistor (BPT) on the incident light intensity P _i . The collector bias voltage V _C is used as a parameter, and at the same time, the change in the base potential of BPT ΔV _B is also shown.

As is clear from Figures 7 and 8, SIPT and
The dependence of the DC optical amplification G on the optical intensity P _i of BPT is completely different. In BPT, the DC optical amplification G gradually increases as the optical intensity P _i increases,
P _i =10 ² μW/cm ² , which is about 3×10 ² at most. on the other hand,
In SIPT, the weaker the light intensity, the more direct current optical amplification G.
tends to increase, and at P _i =10 ⁻⁴ μW/cm ² , a G exceeding 10 ⁸ is obtained.

As mentioned above, the SIT gate structure provides a much larger optical amplification factor (current amplification factor) than the bipolar base structure. Therefore, if the SIT gate structure is applied to the amplification gate structure of an optical trigger thyristor, a trigger thyristor with high optical sensitivity and high speed can be realized.

As an example, when optically triggering a 400V-10A class thyristor, when using the amplification gate structure based on the SIT gate structure according to the present invention, the turn-on delay is 1.8μs with approximately 123μW of light, and the turn-on rise time is 1.1μs. It was hot. When an amplification gate structure based on a bipolar base structure was used instead of the SIT gate structure, the gate potential of the main thyristor rose only to 0.6 eV at the same light intensity, and optical triggering was not possible.

If the optically triggered thyristor according to the present invention is used in a switching device to which a conventional optically triggered thyristor is applied, an extremely high-speed, highly sensitive switching device can be realized. Furthermore, it greatly expands the range of applications of optically triggered thyristors from high power to medium to low power fields, and has high industrial utility value.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention, in which the photo-triggered auxiliary electrostatic induction thyristor has a buried gate structure, and a control resistance and a reverse gate bias are applied between the gate and the cathode. FIG. 2 shows another embodiment of the present invention, in which the cathode electrode and gate electrode of the auxiliary static induction thyristor, the base electrode and the cathode electrode of the main thyristor are all formed to have the same potential, and that the auxiliary static induction thyristor is formed to have the same potential. A light-triggered thyristor with an optical window provided on the cathode surface of the induction thyristor, Fig. 3 shows the following:
In another embodiment of the present invention, the auxiliary electrostatic induction thyristor has a cathode on the surface dug from the main surface;
A planar gate type optical trigger thyristor with a gate formed therein; Fig. 4 shows another structural example of an optical trigger thyristor consisting of a planar gate type auxiliary electrostatic induction thyristor and a main thyristor; Fig. 5 shows an example of an optical trigger thyristor with an auxiliary electrostatic induction thyristor. An example of a photo-triggered thyristor formed in a notch gate type, FIG. 6 is an example of a photo-triggered thyristor in which the auxiliary electrostatic induction thyristor is formed in an MIS gate type, and FIGS. 7 and 8 show the effects of the present invention. Figure 7 shows the DC optical amplification, gate potential change, and dependence of incident light intensity P _i on the SIT gate structure, and Figure 8 shows the DC optical amplification on the bipolar base structure. Amplification degree and gate potential change and dependence of incident light intensity P _i , 9th
The figure shows the structure of an optically triggered thyristor with a conventional amplification gate structure, which is a prior example of the present invention. 111,211,311,411,511,6
11... Cathode region of auxiliary electrostatic induction thyristor, 112, 212, 312, 412, 512,
...the first gate region of the auxiliary electrostatic induction thyristor,
133,232,333,433,533,63
3... Cathode electrode of auxiliary electrostatic induction thyristor,
134,232,334,434,534,63
4...Gate electrode of auxiliary electrostatic induction thyristor, 1
02,102',202,302,402,50
2...n ^- high resistance layer, 602... high resistance layer, 61
2...p ^- high resistance layer, 105, 105', 205,
305, 405, 505, 605, 705...
n ⁺ second gate region, 101, 101', 201,
301, 401, 501, 601, 701...
p ⁺ anode, 131,231,331,431,
531,631,731...p ⁺ anode electrode,
104,204,304,404,504,60
4,704... Cathode region of main thyristor, 1
03,203,303,403,503,60
3,703...Base area of main thyristor, 13
2,232,332,432,532,632,
732...Cathode and base electrode of the main thyristor, 154,354,454,554...Gate resistor R _GK inserted between the first gate and cathode of the auxiliary thyristor, 153,353,453,55
3,653...Bias voltage V _GK applied between the first gate and cathode of the auxiliary thyristor, 152,
252, 352, 452, 552, 652, 75
2...Cathode terminal, 151, 251, 351,
451,551,651,751...Anode terminal, 161,261,361,461,561,
690...Trigger incident light LT, 242...Antireflection film, 613...p ⁺ area.

Claims (1)

[Scope of Claims] 1. A four-layer structure main thyristor and an electrostatic induction thyristor are integrated and formed on the same semiconductor substrate, and the cathode of the four-layer structure main thyristor and the first main electrode of the electrostatic induction thyristor are connected to each other, an anode region of the main thyristor and a second main electrode region of the electrostatic induction thyristor are formed in a common region, and the electrostatic induction thyristor has a function of amplifying the main thyristor. Light-triggered thyristor. 2. The above claim, wherein the electrostatic induction thyristor is formed of a buried gate type electrostatic induction thyristor, and the trigger incident light enters from a beveled surface between a gate electrode and a cathode electrode of the electrostatic induction thyristor. The light-triggered thyristor according to item 1. 3. the electrostatic induction thyristor is formed of a buried gate electrostatic induction thyristor, the triggering incident light enters through an optical window on the cathode region of the electrostatic induction thyristor, and the cathode of the main thyristor;
a base and a cathode of the electrostatic induction thyristor;
2. The optically triggered thyristor according to claim 1, wherein the gates are electrically common. 4. The electrostatic induction thyristor is formed of a planar gate type electrostatic induction thyristor in which a cathode and a gate are formed on a surface recess cut into the cathode main surface of the main thyristor. The light-triggered thyristor according to claim 1, characterized in that the light enters from above the surface of the electric induction thyristor. 5. The electrostatic induction thyristor is formed of a planar gate type electrostatic induction thyristor, and the trigger incident light enters through a beveled surface formed by a groove cut between the planar gate type electrostatic induction thyristor and the main thyristor. The optically triggered thyristor according to claim 1, characterized in that: 6. The above claim, wherein the electrostatic induction thyristor is formed of a notched gate type electrostatic induction thyristor, and the trigger incident light enters from a beveled surface between the cathode electrode and the gate electrode of the electrostatic induction thyristor. The light-triggered thyristor according to item 1. 7. The optical trigger thyristor according to claim 1, wherein the electrostatic induction thyristor is formed of an MIS gate type electrostatic induction thyristor. 8 A four-layer structure main thyristor having a buried gate layer of a static induction transistor gate structure in a high resistance layer near an anode region and a double gate type static induction thyristor are integrated and formed on the same semiconductor substrate. A cathode of the layered main thyristor and a first main electrode of the double-gate electrostatic induction thyristor are connected, and an anode region of the main thyristor and a second main electrode region of the double-gate electrostatic induction thyristor are connected to each other. 1. A light-triggered thyristor, characterized in that the double-gate electrostatic induction thyristor is formed in a common region and has a function of amplifying the main thyristor. 9. Both the first gate and the second gate of the double-gate electrostatic induction thyristor are formed with a buried gate structure, and the trigger incident light enters from a beveled surface between the first gate electrode and the cathode electrode of the electrostatic induction thyristor. The optically triggered thyristor according to claim 8, characterized in that: 10 The first gate and the second gate of the double-gate electrostatic induction thyristor are both formed with a buried gate structure, and the trigger incident light enters through an optical window on the cathode region of the electrostatic induction thyristor, and the main thyristor 9. The optical trigger thyristor according to claim 8, wherein the cathode and the base of the electrostatic induction thyristor and the cathode and the first gate of the electrostatic induction thyristor are electrically common. 11 The double-gate electrostatic induction thyristor has a cathode and a first gate formed in a plane gate structure on a surface recess cut into the cathode main surface of the main thyristor, and a second gate formed in a buried gate structure. 9. The photo-triggered thyristor according to claim 8, wherein the trigger incident light enters the electrostatic induction thyristor from a surface on the cathode side. 12 The first gate of the double-gate electrostatic induction thyristor is formed with a planar gate structure, and the trigger incident light is injected between the electrostatic induction thyristor and the main thyristor from the cathode side surface toward the anode side. Claim 8, characterized in that the penetration occurs from a beveled surface formed by a groove.
The light-triggered thyristor described in section. 13. The first gate of the double-gate electrostatic induction thyristor is formed with a notched gate structure, and the trigger incident light enters from a beveled surface between the cathode electrode and the first gate electrode of the electrostatic induction thyristor. The optically triggered thyristor according to claim 8. 14. The optically triggered thyristor according to claim 8, wherein the first gate of the double-gate electrostatic induction thyristor is formed with an MIS gate structure.