JPH03259214A - Semiconductor optical modulating device - Google Patents

Abstract

PURPOSE:To obtain an excellent storing function by making a 1st semiconductor layer or semiconductor substrate, a 2nd semiconductor layer, a multiple quantum well layer, and 1st-4th semiconductor layers in a semiconductor laminate body transmissive to light having expected wavelength. CONSTITUTION:The semiconductor substrate 51 and semiconductor layers 52, 53, 55, and 56 of the semiconductor laminate body are transmissive to light with expected wavelength lambda0 which is inputted as external light L1 mentioned below. Further, the multiple quantum well layer 5 of the semiconductor laminate body 50 is transmissive to input light L1 having expected wavelength lambda0. Further, power terminals 61 and 62 are led out of the semiconductor layers 52 and 53 of the semiconductor laminate body 50 and a control terminal 63 is led out of the semiconductor layer 53. Consequently, the excellent storing function is obtained.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a semiconductor optical modulator.

[Conventional technology]

Conventionally, a semiconductor optical modulation device has been proposed as described below with reference to FIG. That is, for example, a semiconductor layer or semiconductor substrate 11 having n-type (hereinafter referred to as semiconductor layer 11 for simplicity), and a multiple quantum well in which no impurity giving either n-type or p-type conductivity is intentionally introduced. layer 13 and semiconductor layer 11
A semiconductor stacked body 10 includes a semiconductor layer 12 having a p-type opposite to the semiconductor layer 12 stacked in that order. In this case, the semiconductor stack 10 has opposing main surfaces 10a.
and on 10b, a light entrance surface 15 and a light exit surface 16
have. Further, the semiconductor layers 11 and 12 of the semiconductor stack 10 receive light input from the outside at a wavelength λ which is expected to be incident as 1, as will be described later. For this reason, both are made of GaAS, for example. Furthermore, the multi-quantum well layer 13 of the semiconductor stack 10 has the above-described scheduled wavelength λ. The barrier layer has a relatively small thickness so that the absorption coefficient δ (Cm-1) for light as the input light L1 having Semiconductor 1 with
113a and a relatively thin semiconductor layer 13b serving as a well layer are stacked in alternating order,
Further, similarly to the semiconductor layers 11 and 12, the scheduled wavelength λ mentioned above. Therefore, the semiconductor layer 13a is made of, for example, InGaA.
The semiconductor layer 13a is made of s-based material, and the semiconductor layer 13a is made of I n
When made of GaAS, the semiconductor layer 13b is made of GaAS, for example.
It becomes. Furthermore, from the semiconductor layers 11 and 12 of the semiconductor stack 10,
Control terminals 21 and 22 are led out, respectively. The above is the configuration of a conventionally proposed semiconductor optical modulator. In the conventional semiconductor optical modulator having such a configuration, the semiconductor stack 10 has a semiconductor layer 12 represented by rpJ, a multiple quantum well W13 represented by Fil, and a semiconductor layer 1i13.
When expressed as rnJ, it has a pin element structure, and therefore,
It has a pin junction inside. Therefore, the control power supply 30 is connected between the control terminals 21 and 22.
, the control voltage V. , a semiconductor 11i1 having n-type
If the voltage is applied with a polarity that is positive to the control terminal 21 side derived from 1, the p
A reverse bias voltage is applied to the in junction, so that p
The electric field E is applied to the control voltage ■ in the multi-ff1ffl child well H13 as the i-layer constituting the in junction. occurs with an intensity that depends on the value of . On the other hand, the multiple quantum well layer 13 has a wavelength λ as previously described. The absorption coefficient δ for light as the input light L1 having
The absorption coefficient δ depends on the strength of the electric field E generated in the multiple quantum well layer 113, and the dependence of the absorption coefficient δ on the electric field strength generally depends on the wavelength λ (μm) of the light incident on the multiple quantum well layer 13.
When the electric field E generated in the multiple quantum well layer 13 has a relatively high intensity (this is referred to as EH) in terms of the absorption coefficient δ (Cm-1) for If the light incident on the well layer 13 has a maximum value δHH at a certain wavelength λH, and the electric field E generated in the multi-quantum well layer 13 has a relatively low intensity (this is referred to as E), then as shown in FIG. As shown in curve B, the maximum value δ8 is reached at a wavelength λ that is shorter than the wavelength λ□ of the light incident on the multi-quantum well layer 13.
It takes a higher maximum value δ□ than H, but takes a lower value δ8° than the maximum value δHH at wavelength λ. Therefore, a predetermined wavelength λ is transmitted into the semiconductor stack 10 from the outside on the light entrance surface 15 side through the light entrance surface 15. Suppose that light is input as input light L1 having a control voltage V. has a relatively high expected value (this is designated as ■.H), the absorption coefficient δ of the multiple quantum well layer 13 exhibits an extreme value δHH on the curve A in FIG. The wavelength λ of the light incident on the semiconductor stack 10 as the input light L1 is as shown in FIG. If the above-mentioned wavelength λ□ is selected in advance, the expected wavelength λ will be stored in the semiconductor stack 10. If the control voltage Vc is made to have a high value VCH in a state where the input light L1 having a value of H, a predetermined wavelength λ is present in the semiconductor stack 10. The input light L1 has
If it enters from the outside on the light incidence surface 15 side, at this time,
The absorption coefficient δ of the multiple quantum well layer 13 exhibits a maximum value δ8H on the curve A in FIG. Further, in a state where the value of the wavelength 20 of the light incident as the input light L1 is selected in advance as described above, the semiconductor stack 1
The input light L1 having a predetermined wavelength 2o within 0 is input to the light entrance surface 1.
The control voltage is V when the input is from the outside on the 5 side. the lower value V. , or the control voltage V. the lower value V. , a predetermined wavelength λ is stored in the semiconductor stack 10. If the input light L1 having a value of δ8. It shows. Therefore, while input light L1 having a predetermined wavelength λ0 enters the semiconductor stack 10 from the outside on the light incidence surface 15 side, the control voltage V is applied. ■ High value. H or control voltage V. with high favH,
A wavelength λ is present in the semiconductor stacked body 10 . If input light L1 having a
Output light 2 is output from the exit surface 16 side of 0 to the outside with relatively low intensity 12. It emits light. Further, a predetermined wavelength λ is stored in the semiconductor stacked body 10 . In a state where input light L1 having a current of the lower value V. , or the control voltage V. the lower value V. , wavelength λ is present in the semiconductor stack 10. The input light L having
1 is incident from the outside on the light incidence surface 15 side, the output light L2 is transmitted from the exit surface 16 side of the semiconductor stack 10 to the outside,
The light is emitted with a higher intensity L2H than when the control voltage V is set to a high value ■chH. From the above, in the case of the conventional semiconductor optical modulator shown in FIG.
C has a relatively high value VCH and a low value V. ,
The fact that the output light L2 has a relatively high intensity of 2° and the low intensity L2. To describe the fact that the control voltage V . in binary display “
1" or the value of rOJ, or the control voltage ■
If the input light L1 is made to enter the semiconductor stack 10 from the outside on the light incidence surface 15 side while the value is set to "1" or rOJ in the binary display, the output light L2 will change accordingly. 2
Obtained with an intensity of "O" or "1" in the value display. Therefore, the conventional semiconductor optical modulator shown in FIG. 6 exhibits a luminous intensity m function.

Problem 1 to be Solved by the Invention However, in the case of the conventional semiconductor luminous intensity It device shown in FIG. 6, the control voltage V. The wavelength λ when the value is set to "1" (high value VCH) in 2Wi display. The value δ of the absorption coefficient δ of the multi-quantum well layer 13 for light having The same wavelength λ when the value is set to ``1'' (low value ■) on the 2H value display. Multiffi! for light with Value of absorption coefficient δ of child well layer 13 δ8. If the difference between the two is large, the intensity L2 when the output light L2 is obtained with the binary display "O" and the intensity L2 when the output light L2 is obtained with the binary display "1" are determined accordingly. Strength of 12. However, for this purpose, the control power supply 30
When the pressure vc is obtained as the rlJ value (high value vcH) in the binary representation, the control i11 is the value of "1" in the binary representation, and the value of rOJ in the binary representation (low value V. It is necessary to prepare a power source that has a large difference between rOJ in binary representation when obtained with In the case of the conventional semiconductor optical modulation device shown in FIG. [It is necessary to continuously apply the lN pressure vo between the control terminals 21 and 22 with the value "1" in the binary display, and similarly, the output light L2 must be applied in the binary display. "
In order to obtain a state that continues for a certain period of time as light having an intensity of 1, the control voltage ■ must be applied during that period. of,
It is necessary to continuously apply the value "0" in the binary display between the control terminals 21 and 22, and therefore the control voltage V
. -d, from the value of rOJ in binary display to "1" in binary display.
Even if the output light L2 continues to have the intensity of "0" in the binary display even if the value of rOJ is converted to the value "0" in the binary display, the ill m voltage ■. , -d, binary display "1"
Even if the output light L2 continues to have the intensity of "1" in the binary display even if the value is changed from "0" to the "O" value in the binary display and then returned to the "1" value in the binary display. Even if it is desired to have a memory function such as a memory function, such a device has the disadvantage that such a desired item cannot be satisfied. Therefore, the present invention aims to propose a novel semiconductor optical modulator that does not have the above-mentioned drawbacks. [Means for solving the WI problem] The semiconductor optical modulation device according to the first invention of the present application is
a first semiconductor layer or semiconductor substrate having a conductivity type;
a second semiconductor layer having a second conductivity type opposite to the first conductivity type; and a multi-quantum well in which impurities imparting either the first conductivity type or the second conductivity type are not intentionally introduced. a third semiconductor layer having a first conductivity type, and a fourth semiconductor layer having a second conductivity type; (1) a first power supply terminal led out from the first semiconductor layer or semiconductor substrate; (2) a second power supply terminal led out from the fourth semiconductor layer of the semiconductor stack and paired with the first power supply terminal;
(2) a control terminal led out from the second or third semiconductor layer; (1) The first semiconductor layer or semiconductor substrate, the second semiconductor layer, the multiple quantum well layer, the third semiconductor layer, and the fourth semiconductor layer of the semiconductor stacked body each have an emission surface; Transparent to light having a certain wavelength. Further, the semiconductor optical modulation device according to the second invention of the present application includes:
In the semiconductor optical modulation device according to the first invention of the present application,
The control terminal is omitted, and accordingly, "light having a predetermined wavelength" is read as "first light having a predetermined first wavelength", and the second or third semiconductor of the semiconductor stack This is similar to the semiconductor optical modulator according to the first aspect of the present invention, except that the layer is absorbent to second light having a predetermined second wavelength. [Operation/Effect] In the semiconductor optical modulation device according to the first invention of the present application,
In the semiconductor stack, the first semiconductor layer or semiconductor substrate and the third semiconductor layer are represented by rnJ (or "p"), and the second and fourth semiconductor layers are represented by "p" (or "n"). When a multi-ff1ffi child well layer is represented by Fil, np
i np element structure (or pn i pn element structure)
Therefore, it has two np junctions (or pn junctions) and one pln junction (or nip junction). For this reason, a bias power supply is connected between the first and second power supply terminals with the polarity opposite to the pin junction (or nip junction) in the npinp element structure (or pn i pn element structure). , the first for the current flowing from the bias power supply through the first and second power supply terminals.
Looking at the relationship between the voltages between the second power supply terminal and the second power supply terminal, the current-voltage characteristic exhibits a characteristic represented by an S-curve similar to that of a thyristor having an npnp element structure (or pnpn element structure). Therefore, a bias power supply is connected between the first and second power supply terminals through a load having a value that can draw a load line that intersects the S-curve of the current-voltage characteristic at three points, If the voltage of the bias power supply is selected in advance to be at or near the voltage at the point where the load line intersects the voltage axis of the current-voltage characteristic described above, the semiconductor optical modulator will be able to follow the S-shaped curve described above. The first stable point is the point where the current value is the smallest among the three points where the load line intersects.
The second stable point is the point where the current value is the largest. When the semiconductor optical modulator is operating at the first stable point on the S-curve of the current-voltage characteristics described above, 111FiL flowing through the first and second power supply terminals in the semiconductor stack , Therefore, since a state in which the current flowing through the load has a sufficiently small value (this is called the off state of the semiconductor optical modulator) is obtained, a reverse A large directional bias voltage is applied, and therefore a high electric field is generated in the multi-quantum well layer. However, when the semiconductor optical modulator is operating at the second stable point, , a state is obtained in which the current flowing through the first and second power supply terminals in the semiconductor stack, and therefore the current flowing to the load, has a sufficiently large value (this is called the on state of the semiconductor optical modulator). Therefore, only a small reverse bias voltage is applied to the pin junction (or nip junction).
The electric field is generated only at low strength. On the other hand, it is clear from the description of the conventional semiconductor optical modulator described above in FIG. As shown, there is a difference in absorption coefficient for light having the same wavelength incident on the multi-quantum well layer in the former case than in the latter case. Therefore, suppose that light having a predetermined wavelength is incident as input light into the semiconductor stacked body from outside on the light incidence surface side through the light incidence surface, and at that time, the semiconductor luminous intensity: I
When the device is operating at the first stable point on the S-curve of the current-voltage characteristics described above, the absorption coefficient of the multi-quantum well layer exhibits a high value. However, the semiconductor luminous intensity m device is
When the multi-quantum well layer is operating at a stable point, the absorption coefficient of the multi-quantum well layer exhibits a low value. Therefore, in a state where light having a predetermined wavelength is inputted into the semiconductor stack from the outside on the light incident surface side, the semiconductor optical modulator is controlled to When operating at the stable point of 1, that is, when the semiconductor optical modulator is turned off, or when the semiconductor optical modulator is turned off, light having a predetermined wavelength is input into the semiconductor stack. If the light is made to enter from the outside on the light incident surface side, the output light will be emitted to the outside from the exit surface side of the semiconductor stack with relatively low intensity. Further, in a state where light having a predetermined wavelength is inputted into the semiconductor stack from the outside on the light incident surface side, the semiconductor optical modulator is moved to the second position on the S-curve of the current-voltage characteristic described above. When operating at a stable point, that is, when the semiconductor optical modulator is in the on state, or when the semiconductor optical modulator is in the on state, light having a predetermined wavelength is input into the semiconductor stack. If the light is input from the outside on the incident surface side, the output light will be transmitted to the outside from the output surface side of the semiconductor stack.
The light is emitted with a higher intensity than when the semiconductor optical modulator is turned off. Further, when the semiconductor optical modulator is turned off as described above, the control power source is connected between the control terminal and the first power source terminal when the control terminal is led out from the second semiconductor layer. i np element structure (or pn i p
n element structure) by the first and second semiconductor layers
If the polarity is forward to the p-junction (or pn-junction) and the voltage of the control power supply is selected to an appropriate value in advance, the voltage from the second (or first) semiconductor layer side can be Since a control current flows to the first (or second) semiconductor layer side, electrons (or holes), which are minority carriers, flow into the second (or first) semiconductor layer from the first semiconductor layer side. Therefore, the limiting a power source is controlled so that the maximum voltage value point on the S-curve of the current-voltage characteristic described above crosses the load line only at the S-curve and the second stable point described above. The voltage is lower than that in the case where there is no connection between the terminal and the first power supply terminal, so that the semiconductor optical modulator can be turned on. Also, the semiconductor optical modulator can be turned on as described above. If the control terminal is derived from the third semiconductor layer, an np i np element structure (or pn i pn
np by the third and fourth semiconductor layers in the device structure)
By connecting the junction (or pn junction) with the polarity in the forward direction, and by setting the voltage of the control power supply to an appropriate value in advance, from the fourth (or third) semiconductor layer side,
Since the control current flows to the third (or fourth) semiconductor layer side, holes (or electrons), which are minority carriers, flow into the third semiconductor layer from the fourth semiconductor layer side, and therefore,
The control power supply is controlled so that the maximum voltage value point on the S-curve of the current-voltage characteristics described above crosses the load line only at the S-curve and the second stable point described above.
It is lower than when there is no connection between the Il terminal and the second power supply terminal, and therefore the semiconductor optical modulator can be turned on from an off state. Further, from the state in which the semiconductor optical modulator is turned on as described above, a reset power supply capable of obtaining a reset voltage of zero is connected between the first and second power supply terminals in place of the bias power supply described above. Alternatively, a reset power supply that provides a non-zero reset voltage is connected at a point with a polarity opposite to the p1n junction (or nip junction) in the np i np element structure (or pn i pn structure), or , 6111m In place of the power supply, a reset power supply capable of obtaining a non-zero reset voltage is provided between the control Il terminal and the first power supply terminal, and when the Ii control terminal is derived from the second semiconductor layer, the first semiconductor layer If the control terminal is derived from the third semiconductor layer, the polarity is opposite to the pn junction (or np junction) between the third semiconductor layer and the second semiconductor layer. If the connection is made at one point with the polarity opposite to the np junction (or pn junction) formed by the layer, an npnp element structure (or pn
Similarly to the case of a thyristor having a pn element structure), the semiconductor optical modulator can be returned from an on state to an off state. From the above, in the case of the semiconductor luminous intensity W4 device according to the first invention of the present application, the on state and off state of the semiconductor optical modulation device are respectively indicated by the binary display “
If we state that the output light has a relatively high intensity and that the output light has a relatively low intensity, corresponding to rlJ and ``0'' in the binary representation, the input light into the semiconductor stack If the semiconductor light modulator is made to display "1" or "0" in binary display while inputting from the outside to the light incident surface side, or 1" or rOJ state, if input light is made to enter the semiconductor stack from the outside on the light incident surface side, the output light will be displayed in a binary manner according to this.
It can be obtained with an intensity of "0" or "1". Therefore, the semiconductor optical modulation device according to the first aspect of the present invention also exhibits a light modulation function in the same way as the conventional semiconductor optical modulation device described above with reference to FIG. However, in the case of the semiconductor optical modulator according to the first invention of the present application, since the semiconductor optical modulator has the above-mentioned current-voltage characteristics, the semiconductor optical modulator can be expressed as "1" in the binary display.
The value of the absorption coefficient of the multi-quantum well layer for light having a predetermined wavelength when the semiconductor optical modulator is in the state of ``1'' on the binary display, and the same plan when the semiconductor optical modulator is in the state of ``1'' on the binary display. It is possible to increase the difference between the value of the absorption coefficient of the multi-quantum well layer for light having a wavelength of It can be obtained as having a large difference in intensity from the intensity obtained when the value display is "0". Further, in the case of the semiconductor luminous intensity m device according to the first invention of the present application, the semiconductor optical modulator is turned off and the output light is
From the state obtained with the strength of rOJ in the value display, by simply connecting the control power supply between the control terminal and the first power supply terminal, the control power supply will be connected between the control terminal and the first power supply terminal from the time of the connection start. Even if the first power supply terminal is not connected, the semiconductor optical modulator can be turned on. Therefore, if the control power is connected between the control terminal and the first power supply terminal,
- By only making a temporary connection, even if the control power supply is not connected between the control terminal and the first power supply terminal, the output light will be changed to "1" on the binary display. It exhibits the characteristic of being able to obtain strong and continuous strength. Furthermore, in the case of the semiconductor optical modulator according to the first invention of the present application, the above-mentioned reset power supply , between the first and second power supply terminals or between the control terminal and the first power supply terminal as described above, the reset power supply described above will be activated as described above from the time of connection start. Even if there is no connection between the control terminal and the first power supply terminal, the semiconductor optical modulation device can be turned off. Even if the above-mentioned reset power supply is not connected between the control terminal and the first power supply terminal as described above, from the time when the connection is started, It exhibits a memory function that allows output light to be continuously obtained at the intensity of "O" on a binary display. Furthermore, according to the semiconductor luminous intensity device according to the second invention of the present application,

It has the same configuration as the semiconductor optical modulation device according to the first invention of the present application, except for the matters mentioned above in the column of [Means for solving the WR problem]. Therefore, although a detailed explanation will be omitted, similarly to the case of the semiconductor optical modulation device according to the 1Nth invention of the present application, a predetermined first Suppose that first light having a wavelength of When operating at the first stable point on the S-curve, the multi-quantum well layer exhibits a high absorption coefficient. However, the semiconductor luminosity Il
When the device is operating at the second stable point on the S-curve of current-voltage characteristics similar to that described above, the absorption coefficient of the multiple quantum well layer exhibits a low value. Therefore, as in the case of the semiconductor optical modulation device according to the first invention of the present application, the first light having the first wavelength intended to be inside the semiconductor WA layer is inputted from the outside on the light incidence surface side. If the semiconductor optical modulator is operated at the first stable point on the S-curve of the current-voltage characteristics, that is, is turned off, or the semiconductor optical modulator is is turned off, and if first light having a predetermined first wavelength is made to enter the semiconductor stack as input light from the outside on the light incident surface side, the output surface side of the semiconductor stack Output light is emitted to the outside at a relatively low intensity. Further, as in the case of the semiconductor optical modulation device according to the first invention of the present application, first light having a predetermined first wavelength is made to enter the semiconductor stack from the outside on the light incident surface side as input light. state, the semiconductor optical modulator is connected to the above-mentioned current −
When operating at the second stable point on the S-curve of voltage characteristics, that is, when the semiconductor light modulator is turned on, or when the semiconductor optical modulator is turned on, When first light having a first wavelength of It emits radiation with higher intensity than when it is in the off state. However, in the case of the semiconductor optical modulator according to the eleventh invention of the present application, from the above-mentioned OFF state, from the outside of the semiconductor multilayer body on the light incident surface or light exit surface side. , if a second light having a predetermined second wavelength is made incident as a control light, the second light as a control light will cause the second (or third) light to enter the semiconductor stack.
As a result of absorption in the second (or third) semiconductor layer, minority carriers are generated in the second (or third) semiconductor layer. As in the case of the semiconductor optical modulator according to the invention, a second light as a control light is provided in the semiconductor stack so that the load line intersects the S-shaped curve only at the second stable point. It becomes lower than when it is not incident, and therefore the semiconductor optical modulator can be turned on. Further, from the state in which the semiconductor optical modulator is in the above-mentioned on state, the power supply voltage is changed between the first and second power supply terminals.
As in the case of the semiconductor optical modulator according to the second invention, instead of the bias power supply, a reset power supply capable of obtaining a zero reset voltage is connected, or a reset power supply capable of obtaining a non-zero reset voltage is connected to the np i np element structure. (or pn i pn structure) pin junction (or n
If the semiconductor optical modulator is connected at one point with the polarity opposite to the IP junction), the semiconductor optical modulator changes from the on state to the off state, similar to the case of a thyristor having an npnp element structure (or pnpn element structure). Return. From the above, in the case of the semiconductor optical modulator according to the second invention of the present application, as in the case of the semiconductor optical modulator according to the first invention of the present application, the semiconductor optical modulator is in the on state and the semiconductor optical modulator is in the off state. The states correspond to "1J" and "rOJ" on the binary display, respectively, and "1" and "rOJ" on the binary display indicate that the output light has relatively high intensity and low intensity, respectively. In other words, as in the case of the semiconductor optical modulator according to the first invention of the present application, the semiconductor optical modulator is converted into a binary optical modulator with input light entering the semiconductor stack from the outside on the light incident surface side. When the display shows "1" or "0", or when the semiconductor optical modulator is set to "1" or rOJ on the binary display, input light enters the semiconductor stack. If the light is incident from the outside on the surface side, output light can be obtained with an intensity of rOJ or "1" in binary display. Therefore, the semiconductor optical modulation device according to the second aspect of the present invention also exhibits a light modulation function in the same way as the semiconductor optical modulation device according to the first aspect of the present invention. Further, in the case of the semiconductor filled m-device according to the second invention of the present application, as in the case of the semiconductor optical modulation device according to the first invention of the present application, the semiconductor optical modulation device has the above-mentioned current-voltage characteristics. Semiconductor optical modulator with binary display “1”
The value of the absorption coefficient of the multi-quantum well layer for the first light having the predetermined first wavelength when the semiconductor light modulator is in the state of "1" in the binary display Since the difference between the value of the absorption coefficient of the multi-quantum well layer for the first light having the same scheduled first wavelength when the output light is It can be obtained that there is a large difference between the intensity obtained with "1" and the intensity obtained with binary rOJ. Further, in the case of the semiconductor optical modulator according to the second invention of the present application, the semiconductor optical modulator is turned off and the output light is outputted twice.
From the state where the intensity is "0" on the value display, by simply making the second light having the second wavelength enter the semiconductor stack as control light temporarily, from the moment when it starts entering the semiconductor stack, Since the semiconductor optical modulator can be turned on even when the second light is not being incident on the semiconductor 115, just by temporarily making the second light enter the semiconductor 115, the second light can start to enter the semiconductor 115. From this point on, even if the second light is not entering the semiconductor stack, the output light is
It exhibits a memory function in that it can be obtained continuously with the intensity of "1" on the value display. Furthermore, in the case of the semiconductor optical modulation device according to the second invention of the present application, from a state in which the semiconductor optical modulation device is turned on and the output light is obtained with an intensity of “1” on a binary display,
As in the case of the semiconductor optical modulator according to the second invention, the reset power supply described above is temporarily connected between the first and second power supply terminals or between the control terminal and the first power supply terminal as described above. Even if the above-mentioned reset power supply is not connected between the control terminal and the first power supply terminal as described above, the semiconductor optical modulation device can be turned off from the time when the connection is started. Therefore, the above-mentioned reset power supply can be connected to the control terminal and the first
Even if the above-mentioned reset power supply is not connected between the control terminal and the first power supply terminal as described above, from the time when the connection is started, It exhibits a memory function that allows output light to be continuously obtained at an intensity of "0" in a binary display.

Embodiment 1 Next, a first embodiment of a semiconductor optical modulation device according to the first invention of the present application will be described with reference to FIG. The semiconductor optical modulation device according to the first invention of the present application shown in FIG. 1 has the following configuration. That is, a semiconductor substrate 51, a semiconductor layer 52 having, for example, an n-type and a thickness of, for example, 1 μm, and a semiconductor [5
A semiconductor layer 53 having a p-type opposite to that of 2 and having a thickness of, for example, 0.5 μm, and a multi-quantum well layer in which impurities giving either n-type or p-type conductivity are not intentionally introduced. 54, a semiconductor layer 55 having the same n-type as the semiconductor layer 52 and having a thickness of, for example, 1 μm, and a semiconductor layer 56 having the same p-type as the semiconductor layer 53 and having a thickness of, for example, 0°5 μm. have a semiconductor stacked body 50 which is stacked in that order. In this case, the semiconductor stack 50 has opposing principal surfaces 50a
and on 50b, a light entrance surface 57 and a light exit surface 58
have. In addition, the semiconductor substrate 51 and the semiconductor layer 5 of the semiconductor stack 50
2.53.55 and 56 are wavelengths λ that are scheduled to be input from the outside as input light L1, as will be described later. For this reason, for example, both Ga
It will be AS. Furthermore, the multi-quantum well layer 54 of the semiconductor stack 50 has the above-described scheduled wavelength λ, as in the case of the multi-quantum well layer 13 of the conventional semiconductor optical modulator described above with reference to FIG. Absorption coefficient δ(c m
”) is generated in the multiple quantum well 854 as the electric field E (V/cm
), for example, 50 pairs of semiconductor layers 54a having a relatively thin thickness as a barrier layer and semiconductor layers 1154b having a relatively thin thickness as a well layer are laminated in alternating order. Also, like the semiconductor substrate 51 and the semiconductor layers 52, 53, 55 and 56, the input light having the above-mentioned scheduled wavelength 20 has a transmittance, Therefore, each semiconductor layer 54a
has a thickness of, for example, 80A and is made of, for example, an InGaAS system (for example, InQa AS) 0.2 0.8, and thus each semiconductor 1i54a has a thickness of 80A.
For example, when each semiconductor 1154b has a thickness of 100 A and is made of InGaAs, each semiconductor 1154b has a thickness of 100 A and is made of GaAs.
It becomes. Furthermore, from the semiconductor layers 52 and 53 of the semiconductor stack 50,
Power supply terminals 61 and 62 are led out, respectively. Furthermore, semiconductors! A control terminal 63 is led out from I53. The above is the configuration of the first embodiment of the semiconductor optical modulation device according to the first invention of the present application. In the semiconductor optical modulation device according to the first invention of the present application having such a configuration, the semiconductor stack 50 includes the semiconductor 1
152 and 55 are represented by "n", and semiconductor layers 53 and 56
is expressed as rpJ, and multiple quantum well I! When 54 is represented by "i", it has an npinp element IIa structure, and therefore has two np junctions and one pin junction. Therefore, the bias power supply 70 is connected between the power supply terminals 61 and 62 with a polarity such that the power supply terminal 62 side, which is opposite to the pin junction in the np + np element structure, is positive. From power terminals 61 and 62
Looking at the relationship between the voltage (■) between the power supply terminals 61 and 62 and the current I flowing through it, we can see that the current I-voltage characteristics:
As shown in FIG. 2, it exhibits characteristics expressed by an S-shaped curve 90 similar to that of a thyristor having an npnp element structure. Therefore, the bias power supply 7 is connected between the power supply terminals 61 and 62.
0 to the S-shaped curve 90 and 3 of the current ■-voltage V characteristics described above.
The voltage V of the bias power supply 70 is connected through a load 71 having a value that can draw a load line 91 that intersects at two points. By selecting in advance the voltage v' at the point where the load line 91 intersects the voltage axis of the I-voltage V characteristic described above, or in the vicinity thereof, the semiconductor optical modulator will be able to follow the S-shaped curve 90 described above. The first stable point is point A, which takes the smallest current value among the three intersections of the load line 91 and the load line 91.
The device operates with point B, where the current value is the largest, as the second stable point. When the semiconductor luminous intensity m device is operating at the first stable point of point A on the above-mentioned current I-voltage characteristics S-curve 90, the power terminals 61 and 6 are connected in the semiconductor stack 50.
Since a state has been obtained in which the current flowing through 2 and, therefore, the current flowing to the load has a sufficiently small value (this is called the off state of the semiconductor optical modulator), the pin junction , a reverse bias voltage is applied with a large value vH, and therefore an electric field E with a high intensity EH is generated in the multiple quantum well layer 54. However, the semiconductor optical modulator has the above-mentioned current I-
When operating at the second stable point of point B on the voltage characteristic S-curve 90, the power supply terminal 61 is located within the semiconductor stack 50.
and the current flowing through 62, and therefore the current flowing to the load, has a sufficiently large value ■. (this is called the on state of the semiconductor optical modulator) is obtained, so p
A reverse bias voltage is applied to the in junction with only a small value vL, so that an electric field E of only a low intensity E is generated in the multiple quantum well layer 54. On the other hand, the electric field E in the multiple quantum well layer 54 has a high intensity E
and low intensity E. As is clear from the description of the conventional semiconductor optical modulator described above in FIG. 6, the same wavelength λ incident on the multi-quantum well layer 54 occurs. The absorption coefficient δ (cm") for light with Therefore, an input having a predetermined wavelength λ is input into the semiconductor stack 50 from the outside on the light incidence surface 57 side through the light incidence surface 57. Suppose that light is incident as light L1, and at that time, the semiconductor optical modulator is operating at the first stable point of point A on the above-mentioned current I-voltage characteristics S-shaped curve 90. For example, the absorption coefficient 6 of the multi-quantum well 1i54 exhibits a high value δH. However, the semiconductor optical modulator is stable at the second stable point of point B on the above-mentioned current I-voltage characteristic S-curve 90. When the multi-quantum well layer 54 is in an operating state, the absorption coefficient δ of the multi-quantum well layer 54 exhibits a low value δ. Therefore, the light having the expected wavelength λ0 is input into the semiconductor stack 50 as the input light L1. A state in which the semiconductor optical modulator is operating at the first stable point of point A on the above-mentioned current I-voltage characteristics S-shaped curve 90 with light entering from the outside on the light incidence surface 57 side. , that is, if you turn it off,
Alternatively, when the semiconductor optical modulator is turned off, a predetermined wavelength λ is stored in the semiconductor stack 50. If the light having the input light L1 is made to enter from the outside on the light incidence surface 57 side, from the light exit surface 58 side of the semiconductor stack 50 to the outside,
Output light L2 is emitted with relatively low intensity 12H. Further, a predetermined wavelength λ is stored in the semiconductor stacked body 50 . While input light L1 is incident from the outside on the light incidence surface 57 side, the semiconductor optical modulator is moved to the second point B on the current I-voltage characteristics S-shaped curve 90 described above. When operating at a stable point, ie, in the on state, or when the semiconductor optical modulator is in the on state, a predetermined wavelength λ is present in the semiconductor stack 50. If the input light L1 is made to enter from the outside on the light incident surface 57 side, the output light will be output from the light exit surface 58 side of the semiconductor stack 50 to the outside, and the semiconductor optical modulator 2 will be in the OFF state. The light is emitted at a higher intensity L2H than when the light is set to . Further, from the above-described off state of the semiconductor optical modulator, the control power supply 80 is connected between the ill terminal 63 and the power supply terminal 61 to the np junction formed by the semiconductor [152 and 53 in the npinp element structure]. If the connection is made with the polarity in the forward direction, and the voltage of the i-controlled power supply 80 is selected in advance to an appropriate value, a current will flow from the semiconductor layer 53 side to the semiconductor layer 52 side, so that the semiconductor Electrons, which are minority carriers, flow from the layer 52 side to the semiconductor layer 53 side, and as a result, as shown in FIG. M connects the control power supply 80 to the control terminal 63 and the power supply terminal 61 such that the load line 91 intersects the S-curve 90 only at the second stable point of point B mentioned above.
This is lower than when no connection is made between them, and therefore the semiconductor optical modulator can be turned on. In addition, in place of the bias power supply 70 described above, a reset power supply (not shown) capable of obtaining a reset voltage of zero is connected between the Ti source terminals 61 and 62 from the state in which the semiconductor optical modulator is turned on as described above. ), or temporarily connect a reset power source (not shown) that provides a non-zero reset voltage with the polarity opposite to the pin junction in the np i np element structure, Or, for control terminal 63 and power supply terminal 61 questions,
If a reset power source (not shown) capable of obtaining a non-zero reset voltage is temporarily connected in place of the power source 80 for I11 with a polarity opposite to the n-p junction formed by the semiconductor layers 52 and 53, an npnp element structure can be obtained. Similarly to the case of a thyristor having a thyristor, the semiconductor optical modulator returns from an on state to an off state. From the above, in the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG.
Corresponds to “1” and “0” on the value display, and output light L
2 has a relatively high strength 12N and a low strength L
2, respectively, the binary representation of “1” and rO
Corresponding to J, when the input light L1 is input into the semiconductor stack 50 from the outside on the light incidence surface 57 side, the semiconductor optical modulator is displayed as "1" or "0" in binary display. or when the semiconductor optical modulator is in the state of "1" or "O" in the binary display, the input light L1 is transmitted into the semiconductor stack 50 from the outside on the pre-copper surface 57 side. Accordingly, the output light L2 can be obtained with an intensity of rOJ or "1" in binary representation. Therefore, even in the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG. 1, the luminous intensity i! ! exhibit a function. However, in the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG. 1, since the semiconductor optical modulator has the above-mentioned current I-voltage characteristic, The planned wavelength λ when the state is The value δ1 of the absorption coefficient δ of the multiple quantum well 854 for light having
The same scheduled wavelength λ when the state is maintained. The value δ1 of the absorption coefficient δ of the multiple quantum well layer 54 for light having
It is possible to increase the difference between
Strong IL2 when the value display is "0". It can be obtained as having a large difference between the two. In the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG. 1, the semiconductor optical modulator is turned off and the output light L2 is changed to the intensity L2 of "0" in the binary display. From the state obtained in , the control terminal 63 and the power supply terminal 61 are
By only temporarily connecting the power supply 80, the control power supply 80 is connected to the control terminal 63 and the power supply terminal 6 from the start of the connection.
Since the semiconductor optical modulator can be turned on even when the control I terminal 63 and the power supply terminal 61 are not connected to each other, the control III source 80 is connected between the control I terminal 63 and the power supply terminal 61.
Even if the control power supply 80 is not connected between the control terminal 63 and the power supply terminal 61 from the time when the connection is started, the output light L2 is changed to "1" in the binary display.
It exhibits a memory function that can be obtained continuously with the strength of ``. Furthermore, in the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG. 1, the semiconductor optical modulator is turned on and the output light L2 is obtained with an intensity L2H of "1" in binary display. From the state, the reset power supply described above is connected to the control terminal 63.
As described above, by only temporarily connecting between the control terminal 63 and the power supply terminal 61, the reset power supply described above is not connected between the control terminal 63 and the power supply terminal 61 as described above from the time when the connection is started. The semiconductor luminosity VII device can be turned off even if From the starting point, even if the reset power supply described above is not connected between the control terminal 63 and the power supply terminal 61 as described above, the output light L2 is continuously obtained at the intensity of "O" in the binary display. It exhibits the memory function of being able to do things.

Embodiment 2 Next, a second embodiment of the semiconductor optical modulation device according to the first invention of the present application will be described with reference to FIG. In FIG. 3, parts corresponding to those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted. The semiconductor optical modulation device according to the first invention of the present application shown in FIG. 3 is the semiconductor optical modulation device according to the first invention of the present application described above in FIG. It has the same configuration as the semiconductor optical modulator according to the first invention of the present application described above in FIG. 1, except that it is derived from the semiconductor layer 55 of the semiconductor stack 50 instead of being derived from the semiconductor layer 55. The above is the configuration of the second embodiment of the semiconductor optical modulation device according to the first invention of the present application. According to the second embodiment of the semiconductor optical modulation device according to the first invention of the present application having such a configuration, the semiconductor optical modulation device according to the first invention of the present application described above in FIG. Since it has the same configuration as the device, a detailed explanation will be omitted, but the same effects as in the case of the semiconductor optical modulation device according to the first invention of the present application described above in FIG. 1 can be obtained. However, in the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG.
Since the semiconductor layer 53 in the np I np element structure is led out, the control power supply 80 is connected between the control terminal 63 and the power supply terminal 62 from the state where the semiconductor optical modulator is turned off. 56 with a forward polarity to the np junction, and its control 1
If the voltage of the power supply 80 is appropriately selected in advance, a control current flows from the semiconductor Ji 56 side to the semiconductor 1155 side, so that holes, which are minority carriers, flow into the semiconductor layer 55 from the semiconductor WB2 side. Therefore, the above-mentioned current I-
The control power supply 80 is set so that the maximum voltage value point in the voltage characteristic S-shaped curve 90 crosses the load line 91 only at the second stable point of the S-shaped curve 90 and the above-mentioned point B.
is lower than that when the control terminal 63 and the power supply terminal 62 are not connected. Therefore, the semiconductor optical modulator can be turned on from the off state, and the semiconductor optical modulator can be turned on from the off state. In this state, instead of the bias power supply 70, connect a reset power supply that can provide a zero reset voltage between the power supply terminals 61 and 62, or connect a reset power supply that can provide a non-zero reset voltage between the power supply terminals 61 and 62.
Connect at one point with polarity opposite to the pin junction in the pinp element structure, or
Instead of the power supply 80, between the control terminal 63 and the power supply terminal 62,
If a reset power source that provides a non-zero reset voltage is connected at the - time point with a polarity opposite to the pn junction formed by the semiconductor layer 55 and the semiconductor layer 56, the result will be the same as in the case of a thyristor having an npnp element structure. Since the semiconductor optical modulator can be returned from the on state to the off state, the same effects as in the case of the semiconductor light intensity 11 device according to the first aspect of the present invention described above with reference to FIG. 1 can be obtained.

Embodiment 3 Next, a first embodiment of a semiconductor optical modulation device according to the second invention of the present application will be described with reference to FIG. In FIG. 4, parts corresponding to those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted. The semiconductor optical modulation device according to the second invention of the present application shown in FIG. 4 is the same as the semiconductor optical modulation device according to the first invention of the present application described above in FIG. "Light having a predetermined wavelength λ" is read as "first light having a predetermined wavelength λ1"4, and the semiconductor layers 55 and 56 of the semiconductor stack 50 are the second light having a predetermined second wavelength λ2. It is transparent to the light of
The semiconductor 153 has absorption property for the second light having the predetermined second wavelength λ2, and therefore the semiconductor substrate 51 and the semiconductors 1152 and 53 according to the first invention of the present application shown in FIG. As in the case of semiconductor optical modulators, for example, G
aAS and a multi-quantum well 1i54 semiconductor 11
54a and 54b are A I O, as in the case of the semiconductor optical modulator according to the first invention of the present application shown in FIG.
The semiconductor layer 5 is made of 2Ga 0.8As and GaAs.
5 and 56 are, for example, AlGaAs-based (AI Ga
It has the same configuration as the semiconductor optical modulator according to the first invention of the present application described above in FIG. 1, except that As) is 0.4 0.6. The above is the configuration of the first actual flow example of the semiconductor luminous intensity W4 device according to the second invention of the present application. According to the first embodiment of the semiconductor optical modulation device according to the second invention of the present application having such a configuration, the semiconductor optical modulation device according to the first invention of the application described above in FIG. Although the detailed explanation will be omitted since it has the same configuration as that of the device, as in the case of the semiconductor optical modulation device according to the first invention of the present application described above with reference to FIG.
Assume that a first light having a predetermined first wavelength λ1 is input from the outside on the light incidence surface 57 side through the light incidence surface 57 and is incident as 1, and at that time, the semiconductor light In the case where the modulation device is the semiconductor optical modulation device according to the first invention of the present application described above with reference to FIG. If we are in a state operating at the first stable point, then the multiple quantum well v! The absorption coefficient δ of No. 54 exhibits a high value δH. However, the semiconductor optical modulator has the same current I as described above.
- When operating at the second stable point of point B on the S-curve 90, the absorption coefficient δ of the multi-1ffi well layer 54 exhibits a low value δ[. Therefore, as in the case of the semiconductor optical modulation device according to the first invention of the present application shown in FIG. With the semiconductor luminous intensity Il device in a state where the light is incident from the outside of the 57 incident surfaces, the above-mentioned current ■-voltage characteristics S
operating state at the first stable point of point A on the curve 90;
In other words, if the semiconductor optical modulator is turned off, or while the semiconductor optical modulator is turned off, the semiconductor stack 50
The first light having a predetermined first wavelength λ1 within the input light L
1, if the light enters from the outside on the light incidence surface 57 side, the output light L2 is transmitted from the exit surface 58 side of the semiconductor stack 50 to the outside.
However, the light is emitted with relatively low intensity L21. Further, as in the case of the semiconductor optical modulation device according to the first invention of the present application described above with reference to FIG. A state in which the semiconductor optical modulator is operating at the second stable point of point B on the S-curve 90 of the above-mentioned current ■-voltage ■ characteristic while inputting light from the outside on the entrance surface 57 side;
That is, if the semiconductor optical modulator is turned on, or while the semiconductor optical modulator is turned on, the semiconductor stack 50
The first light having a predetermined first wavelength λ1 within the input light L
1, if the light enters from the outside on the light incidence surface 57 side, the output light L2 is transmitted from the exit surface 58 side of the semiconductor stack 50 to the outside.
However, the light is emitted with a higher intensity of 12H than when the semiconductor optical modulator is turned off. However, in the case of the semiconductor optical modulator according to the second invention of the present application shown in FIG. If a second light having a predetermined second wavelength λ2 is input from the outside as control light L3, the second light as control light L3 will be transmitted to the semiconductor 'fi4M.
By being absorbed by the semiconductor 1153 in the body 50,
Since minority carriers are generated in the semiconductor layer 53, the maximum voltage value point in the above-mentioned current I-voltage characteristic S-curve 90 is Similarly to the above case, the control light L is inserted into the semiconductor stack 50 so that the load line 91 crosses the S-curve 90 only at the second stable point of point B mentioned above.
It is lower than that in the case where the second light No. 3 is not incident, and therefore the semiconductor optical modulator can be turned on. Further, from the above-mentioned ON state of the semiconductor optical modulator, between the power supply terminals 61 and 62, as in the case of the semiconductor optical modulator according to the first invention of the present application described above in FIG. Instead of the bias power supply 70, connect a reset power supply that provides a zero reset voltage, or connect a reset power supply that provides a non-zero reset voltage to npinl.
) By connecting at one point with the polarity opposite to the pin junction in the JK structure, the semiconductor optical modulator returns from the on state to the off state, similar to the case of a thyristor having an npnp element structure. . From the above, in the case of the semiconductor optical modulator according to the second invention of the present application shown in FIG. The binary display “1” and rO indicate that the light modulator is in the on state and in the off state, respectively.
J, and also state that the output light L2 has relatively high intensity and low intensity, respectively, corresponding to "1" and "0" in the binary display, as described above in Fig. 1. As in the case of the semiconductor optical modulation device according to the first invention of the present application, the semiconductor optical modulation device is operated in a binary manner in a state in which the input light L1 is divided by λ from the outside on the light incidence surface 57 side within the semiconductor 18 body 50. If the display shows "1" or "0", or if the semiconductor optical modulator shows the binary display "1" or rOJ, the semiconductor stack 50
If the input light L1 is made to enter from the outside on the light incidence surface 57 side, the output light L2 can be obtained with an intensity of rOJ or "1" in binary representation. Therefore, the semiconductor optical modulation device according to the second invention of the present application shown in FIG. 4 also exhibits the luminous intensity AM function, as in the case of the semiconductor optical modulation device according to the first invention of the present application described above in FIG. . Further, in the case of the semiconductor optical modulation device according to the second invention of the present application shown in FIG. Since it has the above-mentioned current I-voltage characteristics, the multi-quantum well for the first light having the expected first wavelength λ1 when the semiconductor optical modulator is in the state of binary display "1". The value of the absorption coefficient 6 of the layer 54 and the multi-quantum well layer for the first light having the same planned first wavelength λ1 when the semiconductor optical modulator is in the state of 21 [displayed "1"] Since the difference between the value of the absorption coefficient δ of 54 and the value of absorption coefficient δ can be increased, the output light L2 can be
It can be obtained that there is a large difference between the intensity obtained by `` and the intensity obtained by binary rOJ. Further, in the case of the semiconductor optical modulator according to the second invention of the present application shown in FIG. 4, from the state in which the semiconductor optical modulator is turned off and the output light L2 is obtained with an intensity of rOJ in a binary display, By simply making the second light having the second wavelength λ2 enter the semiconductor stack 50 as the control light L3,
The control light L enters the semiconductor stack 50 from the point of time when the incidence starts.
Even if the second light L3 is not incident, the semiconductor optical modulator can be turned on. Even if the second light as the control light L3 is not entered into the semiconductor stacked body 50 from the point of time when the second light enters the semiconductor stack 50, the output light L2 is changed to 2i1.
It exhibits the m* ability that it can be continuously obtained at the indicated intensity of "1". Furthermore, in the case of the semiconductor optical modulator according to the second invention of the present application shown in FIG. 4, the semiconductor optical modulator is turned on and the output light L2 is obtained at an intensity of "1" in binary display. Then, as in the case of the semiconductor optical modulation device according to the first invention of the present application described above in FIG. Even if the above-mentioned reset power supply is not connected between the control terminal 63 and the power supply terminal 61 as described above from the time when the connection is started, the semiconductor optical modulation device can be turned off. Therefore, the reset power supply described above is connected to the control terminal 6 as described above.
3 and the power supply terminal 61, even if the above-mentioned reset power supply is not connected to the control terminal 63 and the power supply terminal 611il from the time of connection start, as described above, rO in binary display of output light L2
It exhibits a memory function that can be obtained continuously at the strength of J.

Embodiment 4 Next, a second embodiment of the semiconductor optical modulation device according to the second invention of the present application will be described with reference to FIG. In FIG. 5, parts corresponding to those in FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted. The semiconductor optical modulator according to the second invention of the present application shown in FIG. 5 is the semiconductor optical modulator according to the second invention of the present application described above in FIG.
3 has absorbency for the second light as the control light L3 having the predetermined second wavelength λ2, and the semiconductor layer 56 absorbs the second light as the control light L3 having the predetermined second wavelength λ2. Therefore, the semiconductor substrate 51, the semiconductor! 52, 53 and 55 are made of GaAs, for example, and the semiconductor layers 54a and 5 of the multiple quantum well layer 54 are made of GaAs.
4b is 0.4 except that 2 08 is made of A1GaAs and GaAs, respectively, and the semiconductor layer 56 is made of, for example, A I GaAS system (for example, AI Ga As).
0.6, and has the same configuration as the semiconductor optical modulator according to the second invention of the present application described above in FIG. The above is the configuration of the second embodiment of the semiconductor optical modulation device according to the second invention of the present application. According to the configuration of the second embodiment of the semiconductor optical modulation device according to the second invention of the present application having such a configuration, except for the above-mentioned matters, the semiconductor optical modulator according to the second invention of the present application described above in FIG. Since it has the same configuration as the optical modulation device, a detailed explanation will be omitted, but the same effects as in the case of the semiconductor optical modulation device according to the second invention of the present application described above in FIG. 4 can be obtained. However, in the case of the semiconductor optical modulation device according to the second invention of the present application shown in FIG. If the second light having the intended wavelength λ2 is made to enter the semiconductor stack 50 from the light incidence surface 57 side as the control light L3 while the modulation device is in the OFF state, 11 control lights will be generated. The second light as L3 is a semiconductor! I5
5, minority carriers are generated in the semiconductor 1155. Therefore, the maximum point in the S-curve 1190 of the current ■-voltage characteristics described above is when the load line 91 is S.
The curve 90 intersects only at the second stable point of the above-mentioned point B, which is lower than when the control light L3 is not incident into the semiconductor stack 50, and therefore, the semiconductor optical modulation Since the device can be turned on from the off state, the same effects as in the case of the semiconductor optical modulation device according to the second invention of the present application described above with reference to FIG. 4 can be obtained. In addition, in the above description, only two embodiments have been described for both the semiconductor optical modulation device according to the first invention of the present application and the semiconductor optical modulation device according to the second invention of the present application. In the embodiments of the semiconductor optical modulation device according to the first invention and the semiconductor optical modulation device according to the twenty-first invention of the present application, “n-type” is read as “ρ-type” and “p-type” is read as “n-type”. It is also possible to obtain the same effects as described above. Further, in the first embodiment of the semiconductor optical modulation device according to the second invention of the present application described above, the semiconductor substrate 51 and the semiconductor layer 52 are exposed to the second light as the control light L3 having the predetermined second wavelength λ2. In addition, in the second embodiment of the semiconductor optical modulation device according to the second invention of the present application described above, the semiconductor substrate 51, the semiconductor layer 5
2 and 53, and the multi-quantum well layer 54 are made to be transparent to the second light as the control light L3 having a predetermined second wavelength λ2, and the control light L3 is transmitted to the semiconductor stack 5.
The same effect as described above can also be obtained by entering the light from the light exit surface 58 side. Furthermore, in the embodiments of the semiconductor y modulation device according to the first invention of the present application and the semiconductor optical modulation device according to the second invention of the present application described above, the semiconductor layer 52 of the semiconductor stack 50
However, in this case, the semiconductor substrate 51 may be of n-type to obtain the same effect as described above, and various other modifications may be made without departing from the spirit of the present invention. Variations and changes may be made.

[Brief explanation of drawings]

FIG. 1 is a linear sectional view showing a first embodiment of a semiconductor optical modulation device according to the first invention of the present application. FIG. 2 is a current I-voltage characteristic diagram for explaining this. FIG. 3 is a cross-sectional view showing an embodiment of M2 of the semiconductor optical modulation device according to the first invention of the present application. FIGS. 4 and 5 are cross-sectional views showing the first and second embodiments of the semiconductor optical modulation device according to the second invention of the present application, respectively. FIG. 6 shows the conventional semiconductor optical sound; l! It is a line cross-sectional view showing one load. FIG. 7 is a diagram showing the relationship between the absorption coefficient δ (Cm-1) and the wavelength λ (μm) of light in a multi-quantum well layer for explanation. 10... Semiconductor laminate 11
．． 12...Semiconductor layer 13...Multi-quantum well layer 2
1.22... Control terminal 30... Control l power supply 50.
...... Semiconductor stacked body 51...
...... Semiconductor substrate 52.53.55
．． 56 ...... Semiconductor layer 54...
......Multiple quantum well layer 57...
...... Light entrance surface 58 ......
......Light exit surface 61.62...Power terminal

Claims (2)

[Claims] 1. A first semiconductor layer or a semiconductor substrate having a first conductivity type, a second semiconductor layer having a second conductivity type opposite to the first conductivity type, and a first semiconductor layer or a semiconductor substrate having a first conductivity type. a multi-quantum well layer in which no impurity giving any of the conductivity types is intentionally introduced; a third semiconductor layer having the first conductivity type;
a semiconductor stacked body in which a fourth semiconductor layer having a conductivity type of a second power terminal led out from a fourth semiconductor layer of the stacked body and paired with the first power terminal; and a control terminal led out from the second or third semiconductor layer; The semiconductor laminate has a light incident surface and a light exit surface on opposing first and second main surfaces, respectively, a first semiconductor layer or a semiconductor substrate of the semiconductor laminate,
A semiconductor optical modulation device characterized in that the second semiconductor layer, the multiple quantum well layer, the third semiconductor layer, and the fourth semiconductor layer are transparent to light having a predetermined wavelength. 2. A first semiconductor layer or semiconductor substrate having a first conductivity type; a second semiconductor layer having a second conductivity type opposite to the first conductivity type; a multi-quantum well layer in which no impurity giving any of the conductivity types is intentionally introduced; a third semiconductor layer having the first conductivity type;
a semiconductor laminate in which a fourth semiconductor layer having a conductivity type is laminated in this order; a first power supply terminal derived from the first semiconductor layer or the semiconductor substrate; a second power supply terminal derived from the first power supply terminal and paired with the first power supply terminal, the semiconductor laminate has a light incident surface and a light output a first semiconductor layer or a semiconductor substrate of the semiconductor stack, each having a surface;
The second semiconductor layer, the multiple quantum well layer, the third semiconductor layer, and the fourth semiconductor layer are transparent to first light having a predetermined first wavelength; A semiconductor optical modulation device characterized in that a second or third semiconductor layer of a semiconductor stack has absorbency for second light having a predetermined second wavelength.