JP4530768B2 - Semiconductor laser device - Google Patents

Description

  The present invention relates to a semiconductor laser device including semiconductor laser elements having different wavelengths.

  In recent years, as the performance of personal computers and multimedia devices has increased, the amount of information to be processed has increased remarkably. As the amount of information increases, an optical recording medium and a driving device for the same have been developed to cope with higher speed and larger capacity of information processing.

  Specific examples of the optical recording medium include a compact disc (hereinafter referred to as a CD) and a digital multipurpose disc (hereinafter referred to as a DVD). Specific examples of driving devices for reproducing and recording these optical recording media include a semiconductor laser device for CD and a semiconductor laser device for DVD. The semiconductor laser device for CD can emit infrared laser light (wavelength of about 790 nm) used when reproducing or recording a CD, and the semiconductor laser device for DVD is used when reproducing or recording a DVD. The red laser light (wavelength around 658 nm) used in the above can be emitted.

  In the following description, a semiconductor laser element that emits infrared laser light (wavelength around 790 nm) is called an infrared semiconductor laser element, and a semiconductor laser element that emits red laser light (around wavelength 658 nm) is called a red semiconductor laser element. .

  As a drive device for an optical recording medium, there is a semiconductor laser device capable of reproducing or recording a CD and a DVD. This semiconductor laser device includes an infrared semiconductor laser element and a red semiconductor laser element, and can emit an infrared laser beam for CD and a red laser beam for DVD.

  When this semiconductor laser device is used, the number of parts can be reduced as compared with the case where a semiconductor laser device for CD and a semiconductor laser device for DVD are used in combination, so that the drive device for the optical recording medium can be simplified. Can be achieved.

  Both the infrared semiconductor laser device and the red semiconductor laser device can be fabricated on a GaAs substrate. Therefore, a monolithic red / infrared semiconductor laser element is manufactured by forming both an infrared semiconductor laser element and a red semiconductor laser element on a GaAs substrate to form a single chip. When the monolithic red / infrared semiconductor laser element manufactured in this way is provided in the above-described semiconductor laser device, the interval between the emission points of the infrared laser light and the red laser light can be precisely controlled.

  On the other hand, semiconductor laser elements for next-generation DVDs that emit blue-violet laser light (wavelength around 400 nm) with a short oscillation wavelength have been developed to improve recording density in optical disc systems. In addition, a semiconductor laser device equipped with a semiconductor laser element that emits the blue-violet laser light has been developed.

  In the following description, a semiconductor laser element that emits blue-violet laser light (having a wavelength of about 400 nm) is referred to as a blue-violet semiconductor laser element.

  Unlike the infrared semiconductor laser element and the red semiconductor laser element, this blue semiconductor laser element is not formed on the GaAs substrate. Therefore, it is very difficult to make the blue semiconductor laser element into one chip together with the infrared semiconductor laser element and the red semiconductor laser element.

  Therefore, a monolithic red / infrared semiconductor laser element is manufactured by forming an infrared semiconductor laser element and a red semiconductor laser element on the same chip, and a blue-violet semiconductor laser element is formed on a separate chip, and then a blue-violet semiconductor is formed. A semiconductor laser device having a structure in which a laser element chip and a monolithic red / infrared semiconductor laser element chip are stacked has been proposed (see Patent Document 1).

  The semiconductor laser device described in Patent Document 1 will be described. FIG. 25 is a schematic diagram showing a semiconductor laser device 900 described in Patent Document 1. As shown in FIG.

  As shown in FIG. 25, the blue-violet semiconductor laser device 901 is bonded to a support member 903a integrated with the package body 903 via a fusion layer 905. The blue-violet semiconductor laser element 901 is mechanically and electrically connected to the support member 903a.

  An electrode 901b and an insulating layer 904 are formed on part of the blue-violet semiconductor laser element 901. An electrode 901a is formed over the insulating layer 904. An infrared semiconductor laser element 902a is bonded to the electrode 901a via a fusion layer 906, and a red semiconductor laser element 902b is bonded to the electrode 901b via a fusion layer 907.

  The infrared semiconductor laser element 902a and the red semiconductor laser element 902b constitute an integrated semiconductor laser element 902 that is monolithically integrated on the same substrate. An electrode 902c is formed on the integrated semiconductor laser element 902.

  The electrode 901a to which the infrared semiconductor laser element 902a is connected is formed on the blue-violet semiconductor laser element 901 with the insulating layer 904 interposed therebetween. As a result, either one of the infrared semiconductor laser element 902a and the red semiconductor laser element 902b can be independently driven.

  The power supply pins 909a to 909c are formed so as to be insulated from the package body 903 by insulating rings 908a to 908c.

  Here, the electrode 901a is used as the p-electrode of the infrared semiconductor laser element 902a, the electrode 901b is used as the n-electrode of the blue-violet semiconductor laser element 901 and the p-electrode of the red semiconductor laser element 902b, and the electrode 902c is the infrared semiconductor. Used as the n-electrode of the laser element 902a and the red semiconductor laser element 902b.

  The electrodes 901a, 901b, and 902c are connected to the power supply pins 909a to 909c by wires JWa to JWc, respectively. The support member 903a is supplied with power from a power supply pin 903b connected to the package body 903.

Accordingly, the semiconductor laser device 900 of FIG. 25 can select and emit any one of infrared laser light, red laser light, and blue-violet laser light.
JP 2001-230502 A

  FIG. 26 is a circuit diagram showing electrical wiring of the semiconductor laser device 900 of FIG.

  As shown in FIG. 26, in order to drive the blue-violet semiconductor laser device 901, it is necessary to apply a negative voltage to the power feed pin 909b with respect to the package body 903 that is generally grounded. Further, in order to drive the red semiconductor laser element 902b, it is necessary to apply a voltage higher than that of the power supply pin 909c to the power supply pin 909b. Furthermore, in order to drive the infrared semiconductor laser element 902a, it is necessary to apply a voltage higher than that of the power supply pin 909c to the power supply pin 909a.

  Therefore, in the semiconductor laser device 900 of FIG. 25, when each semiconductor laser element is driven individually, the control of the drive voltage becomes complicated.

  In addition, when the infrared semiconductor laser element 902a is driven by an alternating voltage, the insulating layer 904 in contact with the electrode 901a in FIG. 25 acts as a dielectric as shown by a broken line in FIG. As a result, a current flows to the red semiconductor laser element 902b through the insulating layer 904, and the high-frequency characteristics of the infrared semiconductor laser element 902a may deteriorate.

  An object of the present invention is to provide a semiconductor laser device in which drive voltage can be easily controlled and deterioration of high-frequency characteristics of a semiconductor laser element due to the influence of an insulating layer can be sufficiently suppressed.

  A semiconductor laser device according to a first invention includes a conductive support member, an insulating layer, a conductive layer formed on one surface of the insulating layer, and a first semiconductor layer formed on a first substrate. A first semiconductor laser element including a first one electrode formed on the first semiconductor layer and a first other electrode formed on the first substrate and emitting light of a first wavelength; A second semiconductor layer formed on the second substrate, a second one electrode formed on the second semiconductor layer, and a second other electrode formed on the second substrate, and having a second wavelength A second semiconductor laser element that emits light, wherein the second semiconductor layer includes a current confinement layer that confines a current flowing from the second one electrode to the second other electrode, and the first one electrode is A first semiconductor laser is provided on the support member so as to be positioned on the support member side, and the first semiconductor laser An insulating layer and a conductive layer are sequentially provided on the first other electrode of the child, and a second semiconductor laser element is provided on the conductive layer so that the second one electrode is electrically connected to the conductive layer. The second other electrode is electrically connected to the first other electrode, and the capacitance value generated in the insulating layer is not more than the capacitance value generated in the current confinement layer.

  In the semiconductor laser device according to the first invention, light having the first wavelength is emitted from the first semiconductor laser element by applying a voltage between the first one electrode and the first other electrode. The Further, a voltage is applied between the second one electrode electrically connected to the conductive layer on the insulating layer and the second other electrode, whereby the second semiconductor laser element has a second wavelength. Light is emitted.

  In this case, the insulating current confinement layer and the insulating layer act as a dielectric when the second semiconductor laser element is driven. Here, the capacitance value generated in the insulating layer is equal to or less than the capacitance value generated in the current confinement layer. Thereby, since the capacitance value of the insulating layer becomes small, the decrease in the cutoff frequency of the second semiconductor laser element due to the influence of the insulating layer becomes sufficiently small. As a result, deterioration of the high frequency characteristics of the second semiconductor laser element due to the influence of the insulating layer is sufficiently suppressed.

  Further, the first other electrode and the second other electrode are electrically connected. Thus, the first and second semiconductor laser elements can be individually driven by applying a voltage to the first and second one electrodes, respectively. As a result, it becomes easy to control the drive voltages of the first and second semiconductor laser elements.

  As described above, the control of the driving voltage is easy, and the deterioration of the high-frequency characteristics of the second semiconductor laser element due to the influence of the insulating layer is sufficiently suppressed.

  Furthermore, a plurality of semiconductor laser devices can be simultaneously manufactured by superimposing a wafer on which a plurality of first semiconductor laser elements are formed and a wafer on which a plurality of second semiconductor laser elements are formed. In this case, the positional accuracy between each first semiconductor laser element and each second semiconductor laser element is improved. As a result, the positioning accuracy of the light emitting points of the first and second semiconductor laser elements is improved.

  The heat generated in the first and second semiconductor laser elements is radiated by the support member. In the semiconductor laser device according to the first invention, the first semiconductor laser element is provided on the support member so that the first one electrode is positioned on the support member side. Thereby, the light emitting point located in the first semiconductor layer approaches the support member. As a result, the heat dissipation of the first semiconductor laser element is improved.

  The capacitance value generated in the insulating layer may be 1/5 or less of the capacitance value generated in the current confinement layer. In this case, since the capacitance value of the insulating layer becomes extremely small, the decrease in the cutoff frequency of the second semiconductor laser element due to the influence of the insulating layer becomes extremely small. As a result, the deterioration of the high-frequency characteristics of the second semiconductor laser element due to the influence of the insulating layer is extremely sufficiently suppressed.

  A semiconductor laser device according to a second invention includes a conductive support member, an insulating layer, a conductive layer formed on one surface of the insulating layer, and a first semiconductor layer formed on a first substrate. A first semiconductor laser element including a first one electrode formed on the first semiconductor layer and a first other electrode formed on the first substrate and emitting light of a first wavelength; A second semiconductor layer formed on the second substrate, a second one electrode formed on the second semiconductor layer, and a second other electrode formed on the second substrate, and having a second wavelength A second semiconductor laser element that emits light, wherein the first semiconductor layer includes a first current confinement layer that confines a current flowing from the first one electrode to the first other electrode; The semiconductor layer includes a second current confinement layer that confines a current flowing from the second one electrode to the second other electrode, The first semiconductor laser element is provided on the support member so that the other electrode is positioned on the support member side, the insulating layer and the conductive layer are provided in order on the first one electrode of the first semiconductor laser element, The second semiconductor laser element is provided on the conductive layer so that one of the two electrodes is electrically connected to the conductive layer, the second other electrode is electrically connected to the first other electrode, and the insulating layer The capacitance value generated in the first current confinement layer is equal to or smaller than the smaller one of the capacitance values generated in the first and second current confinement layers.

  In the semiconductor laser device according to the second invention, light having the first wavelength is emitted from the first semiconductor laser element by applying a voltage between the first one electrode and the first other electrode. The Further, a voltage is applied between the second one electrode electrically connected to the conductive layer on the insulating layer and the second other electrode, whereby the second semiconductor laser element has a second wavelength. Light is emitted.

  In this case, when the first semiconductor laser element is driven, the insulating first current confinement layer and the insulating layer act as a dielectric. Here, the capacitance value generated in the insulating layer is equal to or smaller than the smaller one of the capacitance values generated in the first current confinement layer and the second current confinement layer. Thereby, since the capacitance value of the insulating layer is reduced, the decrease in the cutoff frequency of the first semiconductor laser element due to the influence of the insulating layer is sufficiently reduced. As a result, deterioration of the high frequency characteristics of the first semiconductor laser element due to the influence of the insulating layer is sufficiently suppressed.

  In addition, when the second semiconductor laser element is driven, the insulating second current confinement layer and the insulating layer act as a dielectric. Here, the capacitance value generated in the insulating layer is equal to or less than the capacitance value generated in the second current confinement layer. Thereby, since the capacitance value of the insulating layer becomes small, the decrease in the cutoff frequency of the second semiconductor laser element due to the influence of the insulating layer becomes sufficiently small. As a result, deterioration of the high frequency characteristics of the second semiconductor laser element due to the influence of the insulating layer is sufficiently suppressed.

  Further, the first other electrode and the second other electrode are electrically connected. Thus, the first and second semiconductor laser elements can be individually driven by applying a voltage to the first and second one electrodes, respectively. As a result, it becomes easy to control the drive voltages of the first and second semiconductor laser elements.

  As described above, the drive voltage can be easily controlled, and deterioration of the high frequency characteristics of the first and second semiconductor laser elements due to the influence of the insulating layer is sufficiently suppressed.

  Furthermore, a plurality of semiconductor laser devices can be simultaneously manufactured by superimposing a wafer on which a plurality of first semiconductor laser elements are formed and a wafer on which a plurality of second semiconductor laser elements are formed. In this case, the positional accuracy between each first semiconductor laser element and each second semiconductor laser element is improved. As a result, the positioning accuracy of the light emitting points of the first and second semiconductor laser elements is improved.

  In addition, the first and second semiconductor laser elements are arranged so that the first and second one electrodes face each other through an insulating layer. As a result, the first and second semiconductor layers approach each other, so that the light emitting points of the first and second semiconductor laser elements can be brought closer to each other.

  The capacitance value generated in the insulating layer may be 1/5 or less of the smaller one of the capacitance values generated in the first current confinement layer and the second current confinement layer. In this case, since the capacitance value of the insulating layer becomes extremely small, the decrease in the cutoff frequency of the first and second semiconductor laser elements due to the influence of the insulating layer is remarkably reduced. As a result, deterioration of the high-frequency characteristics of the first and second semiconductor laser elements due to the influence of the insulating layer is extremely sufficiently suppressed.

  The capacitance value generated in the insulating layer may be about 10 pF or less. In this case, since the capacitance value of the insulating layer is about 10 pF or less, the decrease in the cutoff frequency of the first and second semiconductor laser elements due to the influence of the insulating layer is reduced. As a result, deterioration of the high frequency characteristics of the first and second semiconductor laser elements due to the influence of the insulating layer is sufficiently suppressed.

  A semiconductor laser device according to a third aspect of the present invention is a conductive support member, a conductive layer, a first semiconductor layer formed on a first substrate, and a first one formed on the first semiconductor layer. A first semiconductor laser element that includes an electrode and a first other electrode formed on the first substrate and emits light of a first wavelength; and a second semiconductor layer formed on the second substrate; A second semiconductor laser element that includes a second one electrode formed on the second semiconductor layer and a second other electrode formed on the second substrate, and emits light of a second wavelength; The first semiconductor layer includes an insulating first current confinement layer that confines a current flowing from the first one electrode to the first other electrode, and the second semiconductor layer includes the second one electrode from the second one electrode to the first one. 2 includes a second current confinement layer that confines a current flowing through the other electrode, and the conductive layer is insulated from the first one electrode. The first semiconductor laser element is provided on the support member so that the first other electrode is located on the support member side, and the second one electrode is formed in a predetermined region of the first current confinement layer. Is electrically connected to the conductive layer, the second semiconductor laser element is provided on the conductive layer, the second other electrode is electrically connected to the first other electrode, and the first current confinement is The capacitance value generated in the layer may be equal to or less than the capacitance value generated in the second current confinement layer.

  In the semiconductor laser device according to the third invention, light having the first wavelength is emitted from the first semiconductor laser element by applying a voltage between the first one electrode and the first other electrode. The In addition, a voltage is applied between the second one electrode electrically connected to the conductive layer on the predetermined region of the first current confinement layer and the second other electrode, whereby the second semiconductor Light of the second wavelength is emitted from the laser element.

  In this case, the insulating first and second current confinement layers act as a dielectric when the second semiconductor laser element is driven. Here, the capacitance value generated in the first current confinement layer is equal to or less than the capacitance value generated in the second current confinement layer. Thereby, since the capacitance value of the first current confinement layer becomes small, the decrease in the cutoff frequency of the second semiconductor laser element due to the influence of the first current confinement layer becomes sufficiently small. As a result, deterioration of the high frequency characteristics of the second semiconductor laser element due to the influence of the first current confinement layer is sufficiently suppressed.

  Further, the first other electrode and the second other electrode are electrically connected. Thus, the first and second semiconductor laser elements can be individually driven by applying a voltage to the first and second one electrodes, respectively. As a result, it becomes easy to control the drive voltages of the first and second semiconductor laser elements.

  As described above, the control of the driving voltage is easy, and the deterioration of the high-frequency characteristics of the second semiconductor laser element due to the influence of the insulating layer is sufficiently suppressed.

  Furthermore, a plurality of semiconductor laser devices can be simultaneously manufactured by superimposing a wafer on which a plurality of first semiconductor laser elements are formed and a wafer on which a plurality of second semiconductor laser elements are formed. In this case, the positional accuracy between each first semiconductor laser element and each second semiconductor laser element is improved. As a result, the positioning accuracy of the light emitting points of the first and second semiconductor laser elements is improved.

  In addition, the first and second semiconductor laser elements are arranged so that the first and second one electrodes face each other. As a result, the first and second semiconductor layers approach each other, so that the light emitting points of the first and second semiconductor laser elements can be brought closer to each other.

  The capacitance value generated in the first current confinement layer may be 1/5 or less of the capacitance value generated in the second current confinement layer. In this case, since the capacitance value of the first current confinement layer is extremely small, the decrease in the cutoff frequency of the first and second semiconductor laser elements due to the influence of the first current confinement layer is remarkably small. As a result, the deterioration of the high frequency characteristics of the first and second semiconductor laser elements due to the influence of the first current confinement layer is extremely sufficiently suppressed.

  The capacitance value generated in the first current confinement layer may be about 10 pF or less. In this case, since the capacitance value of the first current confinement layer is about 10 pF or less, the decrease in the cutoff frequency of the first and second semiconductor laser elements due to the influence of the first current confinement layer is reduced. As a result, the deterioration of the high frequency characteristics of the first and second semiconductor laser elements due to the influence of the first current confinement layer is sufficiently suppressed.

  A sub-substrate having a predetermined thickness inserted between the support member and the first semiconductor laser element may be further provided. In this case, it is possible to adjust the light emitting point positions of the first and second semiconductor laser elements.

  The first semiconductor laser element may include a nitride semiconductor. Nitride semiconductors have high thermal conductivity. Thereby, the heat dissipation of the first semiconductor laser element is improved. In addition, since the second semiconductor laser element is stacked on the first semiconductor laser element, the heat dissipation of the second semiconductor laser element is also improved.

  The first and second other electrodes may be electrically connected to each other and electrically insulated from the support member. In this case, a voltage can be applied to each of the first and second other electrodes.

  According to the semiconductor laser device of the present invention, the drive voltage can be easily controlled, and the deterioration of the high frequency characteristics of the semiconductor laser element due to the influence of the insulating layer can be sufficiently suppressed.

  Hereinafter, a semiconductor laser device according to an embodiment of the present invention will be described.

(First embodiment)
The semiconductor laser device according to the first embodiment includes a first semiconductor laser element and a second semiconductor laser element. The wavelength of the laser beam emitted from the first semiconductor laser element is different from the wavelength of the laser beam emitted from the second semiconductor laser element.

  In the following description, a semiconductor laser element that emits blue-violet laser light (having a wavelength of about 400 nm) (hereinafter referred to as a blue-violet semiconductor laser element) is used as the first semiconductor laser element.

  A semiconductor laser element that emits red laser light (having a wavelength of about 658 nm) (hereinafter referred to as a red semiconductor laser element) is used as the second semiconductor laser element.

  FIG. 1 is an external perspective view showing the semiconductor laser device according to the first embodiment.

  In FIG. 1, the semiconductor laser device 500 includes a conductive package body 3, power supply pins 1 a, 1 b, 2 and a lid 4.

  The package body 3 is provided with a plurality of semiconductor laser elements, which will be described later, and is sealed with a lid 4. The lid 4 is provided with an extraction window 4a. The extraction window 4a is made of a material that transmits laser light. The power supply pin 2 is mechanically and electrically connected to the package body 3. The power feed pin 2 is used as a ground terminal.

  Details of the semiconductor laser device 500 will be described. Hereinafter, the direction in which the laser light from the semiconductor laser element is emitted will be described as the front.

  2 is a schematic front view showing a state in which the lid 4 of the semiconductor laser device 500 of FIG. 1 is removed, and FIG. 3 is a schematic top view showing a state in which the lid 4 of the semiconductor laser device 500 of FIG. 1 is removed. FIG.

  In the following description, as shown in FIGS. 2 and 3, the emission direction of the laser light from the blue-violet semiconductor laser device 10 and the red semiconductor laser device 20 is defined as the X direction, and they are mutually in a plane perpendicular to the X direction. Two orthogonal directions are defined as a Y direction and a Z direction.

  As shown in FIG. 2, a conductive fusion layer H is formed on the conductive support member 5 integrated with the package body 3. The support member 5 is made of a material having excellent conductivity and thermal conductivity, and the fusion layer H is made of AuSn (gold tin).

  On the fusion layer H, an insulating sub-substrate 31 having conductive layers 31a and 31b on the upper surface and the lower surface is provided. The sub-board 31 is made of AlN (aluminum nitride). The sub-substrate 31 has a thickness of about 200 μm, for example.

  On the conductive layer 31 a of the sub-substrate 31, the blue-violet semiconductor laser element 10 is bonded via a fusion layer H made of AuSn.

  The blue-violet semiconductor laser device 10 has a laminated structure including a p-side pad electrode 10a, an n-side pad electrode 10b, and a current blocking layer 10c. The blue-violet semiconductor laser device 10 is provided such that the p-side pad electrode 10a is on the support member 5 side.

  In FIG. 2, the n-side pad electrode 10 b is located on the upper surface side of the blue-violet semiconductor laser element 10, and the p-side pad electrode 10 a is located on the lower surface side of the blue-violet semiconductor laser element 10. Further, the ridge portion Ri is provided on the p-side pad electrode 10a, and the current blocking layer 10c is provided on both sides of Ri. Details of the blue-violet semiconductor laser element 10 will be described later.

An insulating layer 32 made of SiO ₂ (silicon oxide) is provided on the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10. In the following description, the thickness of the insulating layer 32 is t32. Details of the thickness t32 of the insulating layer 32 will be described later.

  A conductive layer 32 a containing Au is formed on the insulating layer 32. On the conductive layer 32a, the red semiconductor laser element 20 is bonded via a fusion layer H made of AuSn.

  The red semiconductor laser device 20 has a stacked structure including a p-side pad electrode 20a, an n-side pad electrode 20b, and a first current blocking layer 20c. The red semiconductor laser element 20 is provided such that the p-side pad electrode 20a is on the support member 5 side.

  In FIG. 2, the n-side pad electrode 20 b is located on the upper surface side of the red semiconductor laser element 20, and the p-side pad electrode 20 a is located on the lower surface side of the red semiconductor laser element 20. In addition, a ridge portion Ri is provided on the p-side pad electrode 20a, and a first current blocking layer 20c is provided on both sides of Ri. Details of the red semiconductor laser element 20 will be described later.

  The blue-violet semiconductor laser element 10 is provided so as to be positioned at the center of the extraction window 4a (see FIG. 1) of the lid 4.

  As shown in FIGS. 2 and 3, the power supply pins 1a and 1b are electrically insulated from the package body 3 by insulating rings 1z. The power feed pin 1a is electrically connected to the conductive layer 31a on the sub-board 31 through the wire W4. The power feed pin 1b is electrically connected to the conductive layer 32a on the insulating layer 32 through the wire W1.

  On the other hand, the exposed upper surface of the support member 5 and the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 are electrically connected by a wire W3, and the exposed upper surface of the support member 5 and the n-side pad of the red semiconductor laser element 20 are connected. The electrode 20b is electrically connected by a wire W2. As a result, the feed pin 2 is electrically connected to the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20 b of the red semiconductor laser element 20. That is, the cathode common connection of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is realized.

  By applying a voltage between the power supply pins 1a and 2 and between the power supply pins 1b and 2, the blue-violet semiconductor laser device 10 and the red semiconductor laser device 20 can be individually driven.

  FIG. 4 is a circuit diagram showing electrical wiring of the semiconductor laser device 500 according to the first embodiment.

  As described above, the feed pin 2 is electrically connected to the support member 5 and is also electrically connected to the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20b of the red semiconductor laser element 20. Has been.

  On the other hand, the p-side pad electrode 10 a of the blue-violet semiconductor laser element 10 and the p-side pad electrode 20 a of the red semiconductor laser element 20 are electrically insulated from the support member 5, that is, the power feed pin 2.

  In the semiconductor laser device 500 according to the first embodiment, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are individually provided by applying a voltage higher than the ground potential to one of the power supply pins 1a and 1b. Can be driven. As a result, the drive voltage of each semiconductor laser element can be easily controlled.

  By the way, the semiconductor laser device 500 is provided in an optical pickup device or the like. In general, the optical pickup device is driven by an AC voltage. That is, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are driven by an AC voltage. In this case, the sub-board 31 and the insulating layer 32 in FIG. 2 function as a dielectric.

  FIG. 5 is an equivalent circuit diagram for explaining the operation of the sub-substrate 31 and the insulating layer 32 of FIG. 2 as dielectrics.

  FIG. 5A shows an equivalent circuit diagram when driving the blue-violet semiconductor laser device 10, and FIG. 5B shows an equivalent circuit diagram when driving the red semiconductor laser device 20.

  When the blue-violet semiconductor laser device 10 is driven by an AC voltage, the blue-violet semiconductor laser device 10 is expressed as shown in FIG. In this case, the insulating sub-substrate 31 functions as a dielectric connected in parallel with the blue-violet semiconductor laser element 10.

  In general, the capacitance value generated in the insulating layer is expressed by the following equation.

C1 = εs · ε0 · S / d (1)
C1 is a capacitance value generated in the insulating layer, εs is a relative dielectric constant of the insulating layer, and ε0 is a vacuum dielectric constant. S is the area of the insulating layer, and d is the thickness of the insulating layer.

  In the first embodiment, the current blocking layer 10c, which is an insulating layer, has a thickness (Z direction) of 0.5 μm. The blue-violet semiconductor laser device 10 has a width of about 350 μm (Y direction) and a length of about 600 μm (X direction).

The relative permittivity of the current blocking layer 10c made of SiO ₂ is 4, and the permittivity of vacuum is 8.854 × 10 ⁻¹² F / m.

  The width (Y direction) of the ridge Ri formed in the blue-violet semiconductor laser element 10 is very small compared to the width of the blue-violet semiconductor laser element 10. Therefore, the thickness, width and length of the current blocking layer 10c are set to 0.5 μm, 350 μm and 600 μm. In this case, when the capacitance value generated in the current blocking layer 10c is obtained based on the equation (1), the capacitance value generated in the current blocking layer 10c is about 15 pF.

  On the other hand, the thickness of the sub-board 31 is about 200 μm. When the width (Y direction) of the blue-violet semiconductor laser device 10 is about 350 μm and the length (X direction) is about 600 μm, the capacitance value generated in the sub-substrate 31 is obtained based on the formula (1). The capacitance value generated in the sub-substrate 31 when the blue-violet semiconductor laser device 10 is driven is about 100 fF or less.

  As described above, in the first embodiment, the capacitance value generated in the sub-substrate 31 is much smaller than the capacitance value generated in the current blocking layer 10c of the blue-violet semiconductor laser device 10.

  Therefore, when only the blue-violet semiconductor laser device 10 is driven, the sum of the capacitance values generated in the sub-substrate 31 and the current block layer 10c (hereinafter referred to as the effective capacitance value) is the capacitance value generated in the current block layer 10c. Is almost equal to

  The cutoff frequency of the blue-violet semiconductor laser device 10 is calculated based on the effective capacitance value. The higher the cutoff frequency, the better the high frequency characteristics when driving the semiconductor laser device.

  The cutoff frequency of the semiconductor laser element is simply expressed by the following equation.

  fT is a cutoff frequency of the semiconductor laser element, L is an inductance of the semiconductor laser element, and C is an effective capacitance value when the semiconductor laser element is driven.

  In this case, as shown in Expression (2), the cutoff frequency of the blue-violet semiconductor laser device 10 is inversely proportional to the 1/2 power of the effective capacitance value. Therefore, the cutoff frequency increases as the effective capacitance value of the blue-violet semiconductor laser device 10 decreases.

  As described above, when the capacitance value generated in the sub-board 31 is very small compared to the capacitance value generated in the current blocking layer 10c, the decrease in the cutoff frequency due to the influence of the sub-board 31 is sufficiently small. As a result, deterioration of the high frequency characteristics of the blue-violet semiconductor laser device 10 due to the influence of the sub-substrate 31 is sufficiently suppressed.

  On the other hand, when the red semiconductor laser device 20 is driven by an AC voltage, the red semiconductor laser device 20 is expressed as shown in FIG. 5B using the ridge portion Ri as a resistance and the first current blocking layer 20c as a dielectric. . In this case, the insulating layer 32 acts as a dielectric connected in parallel with the red semiconductor laser element 20.

  In the first embodiment, the first current blocking layer 20c serving as a depletion layer has a thickness (Z direction) of 0.5 μm. The red semiconductor laser element 20 has a width of about 200 μm (Y direction) and a length of about 600 μm (X direction). The first current block layer 20c serving as a depletion layer is made of AlInP.

  The width (Y direction) of the ridge Ri formed in the red semiconductor laser element 20 is very small with respect to the width of the red semiconductor laser element 20. Therefore, the thickness, width, and length of the first current blocking layer 20c are set to 0.5 μm, 200 μm, and 600 μm. Moreover, the relative dielectric constant of AlInP is about 13. In this case, when the capacitance value generated in the first current blocking layer 20c is obtained based on the equation (1), the capacitance value generated in the first current blocking layer 20c is about 28 pF.

  Here, the thickness t32 of the insulating layer 32 is set so that the capacitance value generated in the insulating layer 32 is equal to or less than the capacitance value generated in the first current blocking layer 20c.

  For example, when the width (Y direction) of the insulating layer 32 is about 300 μm and the length (X direction) is about 600 μm, the capacitance value generated in the insulating layer 32 when the red semiconductor laser device 20 is driven has the thickness t32 and It is calculated based on the above formula (1). That is, the capacitance value generated in the insulating layer 32 has an inversely proportional relationship with the thickness t32.

  FIG. 6 is a diagram showing the relationship between the capacitance value generated in the insulating layer 32 when the red semiconductor laser device 20 of FIG. 2 is driven and the thickness of the insulating layer 32. In FIG. 6, the vertical axis represents the capacitance value, and the horizontal axis represents the thickness t <b> 32 of the insulating layer 32.

  According to FIG. 6, in order to make the capacitance value generated in the insulating layer 32 equal to or less than the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser device 20, the thickness t32 of the insulating layer 32 is 0.23 μm. It is necessary to set above.

  By setting the thickness t32 of the insulating layer 32 to 0.23 μm or more, the capacitance value generated in the insulating layer 32 becomes equal to or less than the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser element 20.

  The effective capacitance value in this case is the sum of the capacitance value generated in the first current blocking layer 20c and the capacitance value generated in the insulating layer 32, and therefore the capacitance value generated in the first current blocking layer 20c. 2 times or less.

  According to Equation (2), the cutoff frequency of the red semiconductor laser device 20 is inversely proportional to the 1/2 power of the effective capacitance value. As a result, the cutoff frequency of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 when the capacitance value generated in the insulating layer 32 is equal to or lower than the capacitance value generated in the first current blocking layer 20c is as follows. The maximum reduction is about 30% from the cutoff frequency when it is not provided.

  Thus, by setting the thickness of the insulating layer 32 so that the capacitance value generated in the insulating layer 32 is equal to or less than the capacitance value generated in the first current blocking layer 20c, the red semiconductor due to the influence of the insulating layer 32 is obtained. The decrease in the cutoff frequency of the laser element 20 is sufficiently small. That is, the deterioration of the high frequency characteristics of the red semiconductor laser element 20 is sufficiently suppressed.

  Here, the details of the structures of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 will be described.

  Based on FIG. 7, the details of the structure of the blue-violet semiconductor laser device 10 will be described together with the manufacturing method.

  FIG. 7 is a schematic cross-sectional view for explaining details of the structure of the blue-violet semiconductor laser device 10. Also in the following description, the X direction, the Y direction, and the Z direction are defined as in FIGS.

  At the time of manufacturing the blue-violet semiconductor laser device 10, a semiconductor layer having a stacked structure is formed on the n-GaN substrate 1s. The n-GaN substrate 1s has a (0001) Ga surface as a surface and a thickness of about 100 μm. The n-GaN substrate 1s is doped with O (oxygen).

  As shown in FIG. 7A, an n-GaN layer 101, an n-AlGaN cladding layer 102, an n-GaN light guide layer 103, an MQW (as a semiconductor layer having a stacked structure) are formed on an n-GaN substrate 1s. Multiple quantum well) active layer 104, undoped AlGaN cap layer 105, undoped GaN light guide layer 106, p-AlGaN cladding layer 107, and undoped GaInN contact layer 108 are formed in this order. These layers are formed by, for example, MOCVD (metal organic chemical vapor deposition).

  As shown in FIG. 7B, the MQW active layer 104 has a structure in which four undoped GaInN barrier layers 104a and three undoped GaInN well layers 104b are alternately stacked.

  Here, for example, the Al composition of the n-AlGaN cladding layer 102 is 0.15, and the Ga composition is 0.85. The n-GaN layer 101 and the n-AlGaN cladding layer 102 are doped with Si.

  The undoped GaInN barrier layer 104a has a Ga composition of 0.95 and an In composition of 0.05. The undoped GaInN well layer 104b has a Ga composition of 0.90 and an In composition of 0.10. The p-AlGaN cap layer 105 has an Al composition of 0.30 and a Ga composition of 0.70.

  Further, the p-AlGaN cladding layer 107 has an Al composition of 0.15 and a Ga composition of 0.85. The p-AlGaN cladding layer 107 is doped with Mg. The undoped GaInN contact layer 108 has a Ga composition of 0.95 and an In composition of 0.05.

  Among the above semiconductor layers, the p-AlGaN cladding layer 107 is formed with a striped ridge portion Ri extending in the X direction. The ridge portion Ri of the p-AlGaN cladding layer 107 has a width of about 1.5 μm.

  The undoped GaInN contact layer 108 is formed on the upper surface of the ridge portion Ri of the p-AlGaN cladding layer 107. Furthermore, a p-electrode 110 made of Pd / Pt / Au is formed thereon.

A current blocking layer 10c made of SiO ₂ is formed on the upper surface of the flat portion of the p-AlGaN cladding layer 107 and the side surface of the ridge portion Ri, the side surface of the undoped GaInN contact layer 108, and the upper surface and side surfaces of the p electrode 110. The current blocking layer 10c formed in (1) is removed by etching. Then, the p-side pad electrode 10a is formed by sputtering, vacuum vapor deposition, or electron beam vapor deposition so as to cover the upper surfaces of the p electrode 110 and the current blocking layer 10c exposed to the outside.

In this way, a semiconductor layer having a stacked structure is formed on one surface side of the n-GaN substrate 1s. An n-side pad electrode 10b made of Ti / Pt / Au is formed on the other surface side of the n-GaN substrate 1s. Further, an insulating layer 32 made of SiO ₂ is formed in a partial region on the n-side pad electrode 10b, and a conductive layer 32a containing Au is formed on the insulating layer 32.

As described above, in the first embodiment, the current blocking layer 10c made of SiO ₂ has a thickness of 0.5 μm, for example.

  In the blue-violet semiconductor laser device 10, a blue-violet light emitting point is formed at the position of the MQW active layer 104 below the ridge portion Ri. The MQW active layer 104 corresponds to the pn junction surface of the blue-violet semiconductor laser device 10.

  The details of the structure of the red semiconductor laser device 20 will be described together with the manufacturing method based on FIG.

  FIG. 8 is a schematic cross-sectional view for explaining the details of the structure of the red semiconductor laser device 20.

  When the red semiconductor laser device 20 is manufactured, a semiconductor layer having a stacked structure is formed on the n-GaAs substrate 5X. The n-GaAs substrate 5X is doped with Si.

  As shown in FIG. 8A, on the n-GaAs substrate 5X, as a semiconductor layer having a laminated structure, an n-GaAs layer 201, an n-AlGaInP cladding layer 202, an undoped AlGaInP light guide layer 203, an MQW (multiple layer) Quantum well) active layer 204, undoped AlGaInP light guide layer 205, p-AlGaInP first cladding layer 206, p-InGaP etching stop layer 207, p-AlGaInP second cladding layer 208, and p-contact layer 209 are formed in this order. . These layers are formed by, for example, MOCVD (metal organic chemical vapor deposition).

  As shown in FIG. 8B, the MQW active layer 204 has a structure in which two undoped AlGaInP barrier layers 204a and three undoped InGaP well layers 204b are alternately stacked.

  Here, for example, the Al composition of the n-AlGaInP cladding layer 202 is 0.70, the Ga composition is 0.30, the In composition is 0.50, and the P composition is 0.50. The n-GaAs layer 201 and the n-AlGaInP cladding layer 202 are doped with Si.

  The undoped AlGaInP light guide layer 203 has an Al composition of 0.50, a Ga composition of 0.50, an In composition of 0.50, and a P composition of 0.50.

  The undoped AlGaInP barrier layer 204a has an Al composition of 0.50, a Ga composition of 0.50, an In composition of 0.50, and a P composition of 0.50. The undoped InGaP well layer 204b has an In composition of 0.50 and a Ga composition of 0.50. The undoped AlGaInP light guide layer 205 has an Al composition of 0.50, a Ga composition of 0.50, an In composition of 0.50, and a P composition of 0.50.

  Furthermore, the Al composition of the p-AlGaInP first cladding layer 206 is 0.70, the Ga composition is 0.30, the In composition is 0.50, and the P composition is 0.50. The p-InGaP etching stop layer 207 has an In composition of 0.50 and a Ga composition of 0.50.

  The p-AlGaInP second cladding layer 208 has an Al composition of 0.70, a Ga composition of 0.30, an In composition of 0.50, and a P composition of 0.50.

  The p-contact layer 209 has a stacked structure of a p-GaInP layer and a p-GaAs layer. The p-GaInP layer has a Ga composition of 0.5 and an In composition of 0.5.

The composition of the AlGaInP-based material described above is such that a is an Al composition, b is a Ga composition, and c is an In composition when represented by the general formula (Al _a Ga _b ) _0.5 Inc _{c d} . d is a P composition.

  The p-AlGaInP first cladding layer 206, the p-InGaP etching stop layer 207, the p-AlGaInP second cladding layer 208, and the p-contact layer 209, p-GaInP and p-GaAs are doped with Zn.

  The p-AlGaInP second cladding layer 208 and the p-contact layer 209 on the p-InGaP etching stop layer 207 are removed by etching except for a part of the region (center portion).

  As a result, of the semiconductor layers, the p-AlGaInP second cladding layer 208 and the p-contact layer 209 form a striped ridge portion Ri extending in the X direction. The ridge Ri comprising the p-AlGaInP second cladding layer 208 and the p-contact layer 209 has a width of about 2.5 μm.

  On the upper surface of the p-InGaP etching stop layer 207, the side surface of the p-AlGaInP second cladding layer 208, and the side surface of the p-contact layer 209, the first current blocking layer 20c having a thickness of about 0.5 μm and the thickness of about 0 And a second current blocking layer 20d having a thickness of 3 μm is selectively formed. Then, a p-side pad made of Cr / Au is formed by a sputtering method, a vacuum evaporation method or an electron beam evaporation method so as to cover the upper surface of the p-contact layer 209 exposed to the outside and the upper surface of the second current blocking layer 20d. Electrode 20a is formed.

  The first current blocking layer 20c is made of undoped AlInP and functions as a depletion layer. The second current blocking layer 20d is made of n-GaAs.

  Thus, a semiconductor layer having a laminated structure is formed on one surface side of the n-GaAs substrate 5X. Further, an n-side pad electrode 20b made of AuGe / Ni / Au is formed on the other surface side of the n-GaAs substrate 5X.

  In the red semiconductor laser element 20, a red light emitting point is formed at the position of the MQW active layer 204 below the ridge Ri. The MQW active layer 204 corresponds to the pn junction surface of the red semiconductor laser device 20.

  In the semiconductor laser device 500 according to the first embodiment, a semiconductor laser element that emits infrared laser light (near wavelength 790 nm) as the second semiconductor laser element (hereinafter referred to as an infrared semiconductor laser element). May be used. In this case, the p-side pad electrode of the infrared semiconductor laser element 30 is bonded onto the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 as shown in parentheses in FIGS.

  The details of the structure of the infrared semiconductor laser device 30 will be described together with the manufacturing method based on FIG.

  FIG. 9 is a schematic cross-sectional view for explaining details of the structure of the infrared semiconductor laser device 30. At the time of manufacturing the infrared semiconductor laser device 30, a semiconductor layer having a laminated structure is formed on the n-GaAs substrate 5X. The n-GaAs substrate 5X is doped with Si.

  As shown in FIG. 9A, on the n-GaAs substrate 5X, as a semiconductor layer having a laminated structure, an n-GaAs layer 301, an n-AlGaAs cladding layer 302, an undoped AlGaAs light guide layer 303, an MQW (multiple layer). Quantum well) active layer 304, undoped AlGaAs light guide layer 305, p-AlGaAs first cladding layer 306, p-AlGaAs etching stop layer 307, p-AlGaAs second cladding layer 308 and p-GaAs contact layer 309 are formed in this order. The These layers are formed by, for example, MOCVD (metal organic chemical vapor deposition).

  As shown in FIG. 9B, the MQW active layer 304 has a structure in which two undoped AlGaAs barrier layers 304a and three undoped AlGaAs well layers 304b are alternately stacked.

  Here, for example, the Al composition of the n-AlGaAs cladding layer 302 is 0.45 and the Ga composition is 0.55. The n-GaAs layer 301 and the n-AlGaAs cladding layer 302 are doped with Si.

  The undoped AlGaAs light guide layer 303 has an Al composition of 0.35 and a Ga composition of 0.65. The undoped AlGaAs barrier layer 304a has an Al composition of 0.35 and a Ga composition of 0.65. The undoped AlGaAs well layer 304b has an Al composition of 0.10 and a Ga composition of 0.90. The undoped AlGaAs light guide layer 305 has an Al composition of 0.35 and a Ga composition of 0.65.

  Further, the Al composition of the p-AlGaAs first cladding layer 306 is 0.45, and the Ga composition is 0.55. The p-AlGaAs etching stop layer 307 has an Al composition of 0.70 and a Ga composition of 0.30.

  The p-AlGaAs second cladding layer 308 has an Al composition of 0.45 and a Ga composition of 0.55.

  The p-AlGaAs first cladding layer 306, the p-AlGaAs etching stop layer 307, the p-AlGaAs second cladding layer 308, and the p-GaAs contact layer 309 are doped with Zn.

  In the above, the formation of the p-AlGaAs second cladding layer 308 on the p-AlGaAs etching stop layer 307 is performed only on a part (center portion) of the p-AlGaAs etching stop layer 307. Then, a p-GaAs contact layer 309 is formed on the upper surface of the p-AlGaAs second cladding layer 308.

  As a result, of the semiconductor layers, the p-AlGaAs second cladding layer 308 and the p-GaAs contact layer 309 form a striped ridge portion Ri extending in the X direction. The ridge Ri comprising the p-AlGaAs second cladding layer 308 and the p-GaAs contact layer 309 has a width of about 2.8 μm.

  On the upper surface of the p-AlGaAs etching stop layer 307, the side surface of the p-AlGaAs second cladding layer 308, and the side surface of the p-GaAs contact layer 309, the first current blocking layer 30c having a thickness of about 0.5 μm and a thickness of about A second current blocking layer 30d of 0.3 μm is selectively formed by laminating. Then, the p-side made of Cr / Au is formed by sputtering, vacuum evaporation, or electron beam evaporation so as to cover the upper surface of the p-GaAs contact layer 309 exposed to the outside and the upper surface of the second current blocking layer 30d. Pad electrode 30a is formed.

  The first current blocking layer 30c is made of undoped AlGaAs and functions as a depletion layer. The second current blocking layer 20d is made of n-GaAs. The first current blocking layer 30c has an Al composition of 0.65 and a Ga composition of 0.35.

  Thus, a semiconductor layer having a laminated structure is formed on one surface side of the n-GaAs substrate 5X. Further, an n-side pad electrode 30b made of AuGe / Ni / Au is formed on the other surface side of the n-GaAs substrate 5X.

  In the infrared semiconductor laser device 30, an infrared emission point is formed at the position of the MQW active layer 304 below the ridge portion Ri. The MQW active layer 304 corresponds to the pn junction surface of the infrared semiconductor laser element 30.

  Even when the infrared semiconductor laser device 30 that emits infrared laser light (wavelength of about 790 nm) is used as the second semiconductor laser device, the thickness t32 of the insulating layer 32 is set to 0.23 μm or more, so that the insulating layer The capacitance value generated in 32 is equal to or less than the capacitance value generated in the first current blocking layer 30 c of the red semiconductor laser element 30.

  Thereby, the same effect as the case where the red semiconductor laser element 20 is used as the second semiconductor laser element can be obtained.

  In the semiconductor laser device 500 according to the first embodiment, the thickness t32 of the insulating layer 32 is set to 0.46 μm or more, and the capacitance value generated in the insulating layer 32 is set to the red semiconductor laser element 20 or the infrared semiconductor. The capacitance value generated in the first current blocking layers 20c and 30c of the laser element 30 may be about ½ or less.

  The cutoff frequency of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 when the capacitance value generated in the insulating layer 32 is about ½ or less of the capacitance value generated in the first current blocking layers 20c and 30c is The maximum reduction is about 20% from the cut-off frequency when the insulating layer 32 is not provided.

  As described above, by setting the thickness of the insulating layer 32 so that the capacitance value generated in the insulating layer 32 is about ½ or less of the capacitance value generated in the first current blocking layers 20c and 30c, insulation is achieved. The reduction in the cutoff frequency of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 due to the influence of the layer 32 is further reduced. That is, the deterioration of the high frequency characteristics of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 due to the influence of the insulating layer 32 is more sufficiently suppressed.

  In the semiconductor laser device 500 according to the first embodiment, the thickness t32 of the insulating layer 32 is set to 1.20 μm or more, and the capacitance value generated in the insulating layer 32 is set to the red semiconductor laser element 20 or the infrared semiconductor. The capacitance value generated in the first current blocking layers 20c and 30c of the laser element 30 may be about 1/5 or less.

  The cutoff frequency of the red semiconductor laser device 20 and the infrared semiconductor laser device 30 when the capacitance value generated in the insulating layer 32 is about 1/5 or less of the capacitance value generated in the first current blocking layers 20c and 30c is The maximum reduction is about 10% from the cut-off frequency when the insulating layer 32 is not provided.

  In general, the cutoff frequencies of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 vary within a range of about 10% due to variations in the arrangement of the semiconductor laser elements. Therefore, if the reduction of the cut-off frequency of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 is limited to about 10%, the deterioration of the cut-off frequency can be almost ignored.

  Thus, by setting the thickness of the insulating layer 32 so that the capacitance value generated in the insulating layer 32 is about 1/5 or less of the capacitance value generated in the first current blocking layers 20c and 30c, the insulating layer 32 is insulated. The reduction of the cutoff frequency of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 due to the influence of the layer 32 is remarkably reduced. That is, the deterioration of the high-frequency characteristics of the red semiconductor laser device 20 and the infrared semiconductor laser device 30 due to the influence of the insulating layer 32 is extremely sufficiently suppressed.

  In the first embodiment, the capacitance value generated in the insulating layer 32 is less than or equal to the capacitance value generated in the first current blocking layer 20c. Further, the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20b of the red semiconductor laser element 20 are electrically connected. This facilitates control of the driving voltages of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 and sufficiently suppresses deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the insulating layer. .

  Furthermore, a plurality of semiconductor laser devices 500 can be simultaneously manufactured by superimposing a wafer on which a plurality of blue-violet semiconductor laser elements 10 are formed and a wafer on which a plurality of red semiconductor laser elements 20 are formed. In this case, the positional accuracy of each blue-violet semiconductor laser element 10 and each red semiconductor laser element 20 is improved. As a result, the positioning accuracy of the emission points of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is improved.

  Further, by providing the sub-substrate 31 between the support member 5 and the blue-violet semiconductor laser element 10, the emission point positions of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 can be adjusted.

  By using the blue-violet semiconductor laser element 10 containing a nitride semiconductor as the first semiconductor laser element, the heat dissipation of the blue-violet semiconductor laser element 10 is improved. Further, since the red semiconductor laser element 20 is laminated on the blue-violet semiconductor laser element 10, the heat dissipation of the red semiconductor laser element 20 is also improved.

  Heat generated by the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is radiated from the support member 5. In the first embodiment, the blue-violet semiconductor laser element 10 is provided on the support member 5 so that the p-side pad electrode 10a is positioned on the support member 5 side. As a result, the emission point of the blue-violet semiconductor laser element 10 approaches the support member 5. As a result, the heat dissipation of the blue-violet semiconductor laser device 10 is improved.

  The red semiconductor laser element 20 is provided such that the p-side pad electrode 20a is on the support member 5 side. As a result, the light emitting point of the red semiconductor laser element 20 approaches the support member 5, so that heat dissipation is improved.

  In the above description, the red semiconductor laser element 20 as the second semiconductor laser element is stacked on the blue-violet semiconductor laser element 10 as the first semiconductor laser element. However, on the blue-violet semiconductor laser element 10, not only one semiconductor laser element but also a plurality of semiconductor laser elements may be provided in the Y direction. In this case, the type (wavelength) and number of laser beams emitted from the semiconductor laser device 500 can be increased.

  In the above description, the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20 b of the red semiconductor laser element 20 are both connected to the support member 5. However, the n-side pad electrodes 10b and 20b and the support member 5 may be electrically insulated.

  In this case, floating connection of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 can be realized. Thereby, an arbitrary voltage can be applied to the power supply pins electrically connected to the n-side pad electrodes 10b and 20b of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20. As a result, it becomes easy to control the driving voltages of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 by the driving device of the semiconductor laser device 500.

  In the first embodiment, the support member 5 corresponds to a support member, the insulating layer 32 corresponds to an insulating layer, and the conductive layer 32a corresponds to a conductive layer.

  The n-GaN substrate 1s corresponds to the first substrate, the semiconductor layer on the n-GaN substrate 1s corresponds to the first semiconductor layer, the p-side pad electrode 10a corresponds to the first one electrode, The n-side pad electrode 10b corresponds to the first other electrode, the blue-violet laser light corresponds to the first wavelength light, and the blue-violet semiconductor laser element 10 corresponds to the first semiconductor laser element.

  Further, the n-GaAs substrate 5X corresponds to the second substrate, the semiconductor layer on the n-GaAs substrate 5X corresponds to the second semiconductor layer, and the p-side pad electrode 20a and the p-side pad electrode 30a are the second substrate. It corresponds to one electrode, the n-side pad electrode 20b and the n-side pad electrode 30b correspond to the second other electrode, the red laser light and the infrared laser light correspond to light of the second wavelength, and the red semiconductor laser The element 20 and the infrared semiconductor laser element 30 correspond to a second semiconductor laser element, and the first current block layer 20c and the first current block layer 30c correspond to a current confinement layer.

(Second Embodiment)
The semiconductor laser device according to the second embodiment is different in configuration and operation from the semiconductor laser device 500 according to the first embodiment in the following points.

  FIG. 10 is a schematic front view showing a state in which the lid 4 of the semiconductor laser device according to the second embodiment is removed, and FIG. 11 shows the lid 4 of the semiconductor laser device according to the second embodiment. It is a typical top view which shows the state removed.

  As shown in FIG. 10, a conductive fusion layer H is formed on the conductive support member 5 integrated with the package body 3.

  On the fusion layer H, the blue-violet semiconductor laser device 10 is bonded so that the n-side pad electrode 10b is on the support member 5 side.

An insulating layer 32 made of SiO ₂ (silicon oxide) is provided on the p-side pad electrode 10 a of the blue-violet semiconductor laser element 10. Also in the second embodiment, the thickness of the insulating layer 32 is t32. Details of the thickness t32 of the insulating layer 32 will be described later.

  A conductive layer 32 a containing Au is formed on the insulating layer 32. On the conductive layer 32a, the red semiconductor laser element 20 is bonded via a fusion layer H made of AuSn so that the p-side pad electrode 20a is on the support member 5 side.

  As shown in parentheses in FIG. 10, an infrared semiconductor laser element 30 may be stacked on the blue-violet semiconductor laser element 10 instead of the red semiconductor laser element 20. When the infrared semiconductor laser element 30 is stacked on the blue-violet semiconductor laser element 10, the infrared semiconductor laser element 30 is provided so that the p-side pad electrode 30a is on the support member 5 side.

  As shown in FIGS. 10 and 11, the power supply pins 1a and 1b are electrically insulated from the package body 3 by the insulating ring 1z, respectively. The power feed pin 1a is electrically connected to the p-side pad electrode 10a of the blue-violet semiconductor laser device 10 through the wire W3. The power feed pin 1b is electrically connected to the conductive layer 32a on the insulating layer 32 through the wire W1. The exposed upper surface of the support member 5 and the n-side pad electrode 20b of the red semiconductor laser element 20 are electrically connected by a wire W2.

  The n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 is electrically connected via the fusion layer H on the support member 5. As a result, the feed pin 2 is electrically connected to the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20 b of the red semiconductor laser element 20. That is, the cathode common connection of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is realized.

  By applying a voltage between the power supply pins 1a and 2 and between the power supply pins 1b and 2, the blue-violet semiconductor laser device 10 and the red semiconductor laser device 20 can be individually driven. The electrical wiring of the semiconductor laser device 500 according to the second embodiment is the same as that in FIG. Therefore, also in the semiconductor laser device 500 according to the second embodiment, it is easy to control the drive voltage of each semiconductor laser element.

  When the semiconductor laser device 500 according to the second embodiment is driven by an AC voltage, the insulating layer 32 in FIG. 10 acts as a dielectric as in the first embodiment.

  FIG. 12 is an equivalent circuit diagram for explaining the action of the insulating layer 32 of FIG. 10 as a dielectric.

  12A shows an equivalent circuit diagram when the blue-violet semiconductor laser device 10 is driven, and FIG. 12B shows an equivalent circuit diagram when the red semiconductor laser device 20 is driven.

  When the blue-violet semiconductor laser device 10 is driven by an alternating voltage, the blue-violet semiconductor laser device 10 is expressed as shown in FIG. 12A using the ridge portion Ri as a resistor and the current block layer 10c as a dielectric. Further, the red semiconductor laser element 20 is expressed as shown in FIG. 12A with the ridge portion Ri as a resistor, the first current blocking layer 20c as a dielectric, and the pn junction surface as a dielectric. Furthermore, the insulating layer 32 acts as a dielectric as in the first embodiment.

  Thus, when the blue-violet semiconductor laser device 10 is driven by an AC voltage, the series circuit of the insulating layer 32 and the red semiconductor laser device 20 is connected in parallel to the blue-violet semiconductor laser device 10.

  On the other hand, when the red semiconductor laser device 20 is driven by an AC voltage, the red semiconductor laser device 20 is expressed as shown in FIG. 12B using the ridge portion Ri as a resistor and the first current blocking layer 20c as a dielectric. .

  When the blue-violet semiconductor laser device 10 is driven by an AC voltage, the blue-violet semiconductor laser device 10 uses the ridge Ri as a resistance, the current blocking layer 10c as a dielectric, and the pn junction surface as a dielectric as shown in FIG. It is expressed as follows. Even in this case, the insulating layer 32 acts as a dielectric.

  As shown in FIGS. 12A and 12B, when one semiconductor laser element is driven, the other current blocking layer and the pn junction surface are connected in series with the insulating layer 32. Thereby, the combined capacitance value of the insulating layer 32 and the current blocking layer and the pn junction surface of the other semiconductor laser element is reduced. As a result, the influence of the insulating layer 32 on one semiconductor laser element is reduced.

  Further, as described in the first embodiment, the capacitance value generated in the current blocking layer 10c when the blue-violet semiconductor laser device 10 is driven is about 15 pF. Thereby, when the blue-violet semiconductor laser device 10 is driven, the capacitance value generated in the insulating layer 32 is preferably about 15 pF or less. In this case, deterioration of the high frequency characteristics of the blue-violet semiconductor laser device 10 due to the influence of the insulating layer 32 is sufficiently suppressed.

  The capacitance value generated in the first current blocking layer 20c when the red semiconductor laser device 20 is driven is about 28 pF. Thereby, when the red semiconductor laser device 20 is driven, the capacitance value generated in the insulating layer 32 is preferably about 28 pF or less. In this case, deterioration of the high frequency characteristics of the red semiconductor laser element 20 due to the influence of the insulating layer 32 is sufficiently suppressed.

  From the above, by setting the capacitance value generated in the insulating layer 32 to about 15 pF or less, the deterioration of the high-frequency characteristics of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 due to the influence of the insulating layer 32 is sufficiently suppressed. be able to.

  Therefore, in the second embodiment, the thickness t32 of the insulating layer 32 is set so that the capacitance value generated in the insulating layer 32 is equal to or less than the capacitance value generated in the current blocking layers 10c and 20c.

  In order to set the capacitance value generated in the insulating layer 32 to about 15 pF or less, it is necessary to set the thickness t32 of the insulating layer 32 to 0.43 μm or more based on FIG.

  By setting the thickness t32 of the insulating layer 32 to 0.43 μm or more, the capacitance value generated in the insulating layer 32 is the capacitance value generated in the current blocking layers 10c and 20c of the blue-violet semiconductor laser device 10 and the red semiconductor laser device 20. It becomes as follows.

  In this case, the effective capacitance value is not more than twice the capacitance value generated in the current blocking layers 10c and 20c. As a result, the insulating layer 32 provides the cutoff frequency of the blue-violet semiconductor laser device 10 and the red semiconductor laser device 20 when the capacitance value generated in the insulating layer 32 is equal to or less than the capacitance value generated in the current blocking layers 10c and 20c. If it is not possible, it is reduced to about 30% at the maximum from the cut-off frequency.

  In this way, the blue-violet semiconductor due to the influence of the insulating layer 32 is set by setting the thickness of the insulating layer 32 so that the capacitance value generated in the insulating layer 32 is equal to or less than the capacitance value generated in the current blocking layers 10c and 20c. The decrease in the cutoff frequency of the laser element 10 and the red semiconductor laser element 20 is sufficiently small. That is, deterioration of the high frequency characteristics of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 due to the influence of the insulating layer 32 is sufficiently suppressed.

  Note that the thickness t32 of the insulating layer 32 is set to 0.86 μm or more, and the capacitance value generated in the insulating layer 32 is about ½ or less of the capacitance value generated in the current blocking layer 10c of the blue-violet semiconductor laser element 10. Good.

  The cutoff frequency of the blue-violet semiconductor laser device 10 when the capacitance value generated in the insulating layer 32 is about ½ or less of the capacitance value generated in the current blocking layer 10c is the cutoff frequency when the insulating layer 32 is not provided. The maximum decline is about 20%.

  As described above, by setting the thickness of the insulating layer 32 so that the capacitance value generated in the insulating layer 32 is about ½ or less of the capacitance value generated in the current blocking layer 10c, the influence of the insulating layer 32 affects the capacitance value. The decrease in the cut-off frequency of the blue-violet semiconductor laser device 10 is further reduced. That is, the deterioration of the high frequency characteristics of the blue-violet semiconductor laser device 10 due to the influence of the insulating layer 32 is more sufficiently suppressed.

  Furthermore, the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser device 20 is larger than that of the current blocking layer 10c with respect to the blue-violet semiconductor laser device 10. Therefore, the decrease in the cutoff frequency of the red semiconductor laser element 20 due to the influence of the insulating layer 32 is further reduced. That is, the deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the insulating layer 32 is more sufficiently suppressed.

  Further, the thickness t32 of the insulating layer 32 is set to 1.20 μm or more, and the capacitance value generated in the insulating layer 32 is set to about 1/5 or less of the capacitance value generated in the current blocking layer 10c of the blue-violet semiconductor laser device 10. Good.

  When the capacitance value generated in the insulating layer 32 is about 1/5 or less of the capacitance value generated in the first current blocking layers 20c and 30c, the cutoff frequency of the blue-violet semiconductor laser device 10 is provided with the insulating layer 32. Only about 10% lower than the cutoff frequency in the absence.

  Thus, the blue-violet semiconductor laser element due to the influence of the insulating layer 32 is set by setting the thickness of the insulating layer 32 so that the effective capacitance value is about 1/5 or less of the capacitance value generated in the current blocking layer 10c. The decrease in the cutoff frequency of 10 is significantly reduced. That is, the deterioration of the high-frequency characteristics of the blue-violet semiconductor laser element 10 due to the influence of the insulating layer 32 is extremely sufficiently suppressed.

  Furthermore, the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser device 20 is larger than that of the current blocking layer 10c with respect to the blue-violet semiconductor laser device 10. Therefore, the decrease in the cutoff frequency of the red semiconductor laser element 20 due to the influence of the insulating layer 32 is remarkably reduced and can be almost ignored. That is, the deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the insulating layer 32 is extremely sufficiently reduced.

  The thickness t32 of the insulating layer 32 may be set to 0.65 μm or more. According to FIG. 6, the capacitance value generated in the insulating layer 32 can be set to 10 pF or less by setting the thickness t32 of the insulating layer 32 to 0.65 μm or more. Therefore, the effective capacitance value of the blue-violet semiconductor laser device 10 when the blue-violet semiconductor laser device 10 is driven is about 23 to 24 pF. Here, the capacitance value generated at the pn junction surface of the red semiconductor laser element 20 is not considered.

  Usually, the blue-violet semiconductor laser device 10 has an inductance of about 3 nH. Based on the above effective capacitance value and the above equation (2), the cutoff frequency of the blue-violet semiconductor laser device 10 is calculated. When the capacitance value generated in the insulating layer 32 is 10 pF or less, the cutoff frequency of the blue-violet semiconductor laser device 10 is 600 MHz or more.

  In general, in an optical pickup device including the blue-violet semiconductor laser element 10, it is preferable to set the cutoff frequency of the blue-violet semiconductor laser element 10 to 600 MHz or more.

  Therefore, in the semiconductor laser device 500 according to the second embodiment, the cutoff frequency of the blue-violet semiconductor laser element 10 is set to 600 MHz or more by setting the thickness t32 of the insulating layer 32 to 0.65 μm or more. Good performance can be obtained when used in an optical pickup device or the like.

  In the second embodiment, the capacitance value generated in the insulating layer 32 is equal to or smaller than the smaller one of the capacitance values generated in the current block layer 10c and the first current block layer 20c. Further, the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20b of the red semiconductor laser element 20 are electrically connected. This facilitates control of the driving voltages of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 and sufficiently suppresses deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the insulating layer. .

  Furthermore, a plurality of semiconductor laser devices 500 can be simultaneously manufactured by superimposing a wafer on which a plurality of blue-violet semiconductor laser elements 10 are formed and a wafer on which a plurality of red semiconductor laser elements 20 are formed. In this case, the positional accuracy of each blue-violet semiconductor laser element 10 and each red semiconductor laser element 20 is improved. As a result, the positioning accuracy of the emission points of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is improved.

  Further, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are arranged so that the p-side pad electrode 10a and the p-side pad electrode 20a face each other with the insulating layer 32 interposed therebetween. Thereby, the semiconductor layer of the blue-violet semiconductor laser element 10 and the semiconductor layer of the red semiconductor laser element 20 are close to each other, so that the emission points of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 can be brought close to each other. Thereby, when the laser light emitted from the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is transmitted through the condenser lens, aberration due to the lens can be suppressed.

  In the semiconductor laser device 500 according to the second embodiment, the sub-substrate 31 is not provided between the support member 5 and the blue-violet semiconductor laser element 10. A substrate 31 may be provided.

  In this case, the position of each light emitting point of the blue-violet semiconductor laser element 10, the red semiconductor laser element 20, and the infrared semiconductor laser element 30 can be adjusted by the thickness of the sub-substrate 31.

  Further, when the sub-substrate 31 is provided between the support member 5 and the blue-violet semiconductor laser device 10, the n-side pad electrode 10 b of the blue-violet semiconductor laser device 10 and the support member 5 are electrically insulated by the sub-substrate 31. Good. In this case, floating connection of the blue-violet semiconductor laser device 10 can be realized. Thereby, an arbitrary voltage can be applied to the power supply pin that is electrically connected to the n-side pad electrode 10 b of the blue-violet semiconductor laser device 10. As a result, it becomes easy to control the driving voltages of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 by the driving device of the semiconductor laser device 500.

  In the second embodiment, the current block layer 10c corresponds to the first current confinement layer, and the first current block layers 20c and 30c correspond to the second current confinement layer.

(Third embodiment)
The semiconductor laser device according to the third embodiment is different in configuration and operation from the semiconductor laser device 500 according to the second embodiment in the following points.

  FIG. 13 is a schematic front view showing a state in which the lid 4 of the semiconductor laser device according to the third embodiment is removed, and FIG. 14 shows the lid 4 of the semiconductor laser device according to the third embodiment. It is a typical top view which shows the state removed.

  As shown in FIG. 13, a conductive fusion layer H is formed on a conductive support member 5 integrated with the package body 3. On the fusion layer H, the blue-violet semiconductor laser device 10 is bonded so that the n-side pad electrode 10b is on the support member 5 side.

  In the third embodiment, the width (Y direction) and the length (X direction) of the blue-violet semiconductor laser device 10 are larger than those of the blue-violet semiconductor laser device 10 in the first embodiment.

The p-side pad electrode 10a of the blue-violet semiconductor laser device 10 is formed in a partial region of the current blocking layer 10c formed in the semiconductor layer. As a result, the current blocking layer 10c constricts the current flowing through the blue-violet semiconductor laser device 10 under the p-side pad electrode 10a. That is, the ridge Ri is formed under the p-side pad electrode 10a. As described above, the current blocking layer 10c is made of SiO _2.

  In the XY plane, a conductive layer 33 containing Au is formed in another region of the current blocking layer 10c in a state of being separated from the p-side pad electrode 10a. The formation region of the conductive layer 33 in the XY plane is referred to as a conductive layer formation region.

  On the conductive layer 33, the red semiconductor laser element 20 is bonded via a fusion layer H made of AuSn so that the p-side pad electrode 20a is on the support member 5 side.

  As shown in parentheses in FIG. 13, an infrared semiconductor laser element 30 may be stacked on the blue-violet semiconductor laser element 10 instead of the red semiconductor laser element 20.

  As shown in FIGS. 13 and 14, the power supply pins 1 a and 1 b are electrically insulated from the package body 3 by insulating rings 1 z. The power feed pin 1a is electrically connected to the p-side pad electrode 10a of the blue-violet semiconductor laser device 10 through the wire W3. The power feed pin 1b is electrically connected to the conductive layer 33 via the wire W1. The exposed upper surface of the support member 5 and the n-side pad electrode 20b of the red semiconductor laser element 20 are electrically connected by a wire W2.

  The n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 is electrically connected via the fusion layer H on the support member 5. As a result, the feed pin 2 is electrically connected to the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20 b of the red semiconductor laser element 20. That is, the cathode common connection of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is realized.

  By applying a voltage between the power supply pins 1a and 2 and between the power supply pins 1b and 2, the blue-violet semiconductor laser device 10 and the red semiconductor laser device 20 can be individually driven.

  The electrical wiring of the semiconductor laser device 500 according to the third embodiment is the same as that in FIG. Therefore, also in the semiconductor laser device 500 according to the third embodiment, it is easy to control the drive voltage of each semiconductor laser element.

  Here, also in the third embodiment, when the red semiconductor laser device 20 is driven by an AC voltage, the current blocking layer 10c in the conductive layer forming region acts as a dielectric. Therefore, in the third embodiment, it is preferable that the capacitance value generated in the current blocking layer 10c in the conductive layer formation region is equal to or less than the capacitance value generated in the first current blocking layer 20c.

  As shown in the first embodiment, when the thickness, width and length of the first current blocking layer 20c are 0.5 μm, 200 μm and 600 μm, the capacitance value generated in the first current blocking layer 20c Is about 28 pF.

Here, the area of the conductive layer formation region in the XY plane is the same as that of the insulating layer 32 (conductive layer 32a) described in the first embodiment. That is, the width (Y direction) of the conductive layer formation region is about 300 μm and the length (X direction) is about 600 μm. In order to do this, it is necessary to set the thickness of the current blocking layer 10c to 0.23 μm or more based on FIG.

  Thus, by setting the thickness of the current blocking layer 10c to 0.23 μm or more, the capacitance value generated in the current blocking layer 10c is equal to or less than the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser element 20. It becomes.

  The effective capacitance value in this case is not more than twice the capacitance value generated in the first current blocking layer 20c. As a result, the cutoff frequency of the red semiconductor laser device 20 when the capacitance value generated in the current blocking layer 10c is equal to or less than the capacitance value generated in the first current blocking layer 20c is the case where the current blocking layer 10c is not provided. Only a maximum of about 30% of the cut-off frequency can be reduced.

  Thus, by setting the thickness of the current blocking layer 10c so that the capacitance value generated in the current blocking layer 10c is equal to or less than the capacitance value generated in the first current blocking layer 20c, the influence of the current blocking layer 10c is affected. The decrease in the cut-off frequency of the red semiconductor laser element 20 due to is sufficiently small. That is, the deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the current blocking layer 10c is sufficiently suppressed.

  The thickness of the current blocking layer 10c is set to 0.46 μm or more, and the capacitance value generated in the current blocking layer 10c is about ½ of the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser element 20. It is good also as follows.

  The cutoff frequency of the red semiconductor laser element 20 when the capacitance value generated in the current blocking layer 10c is about ½ or less of the capacitance value generated in the first current blocking layer 20c is when the insulating layer 32 is not provided. It is only about a 20% drop from the cut-off frequency.

  Thus, by setting the thickness of the current blocking layer 10c so that the capacitance value generated in the current blocking layer 10c is about ½ or less of the capacitance value generated in the first current blocking layer 20c, the current The reduction in the cut-off frequency of the red semiconductor laser element 20 due to the influence of the block layer 10c is further reduced. That is, the deterioration of the high frequency characteristics of the red semiconductor laser element 20 due to the influence of the current blocking layer 10c is more sufficiently suppressed.

  Further, the thickness of the current blocking layer 10c is set to 1.20 μm or more, and the capacitance value generated in the current blocking layer 10c is set to about 1/5 of the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser device 20. It is good also as follows.

  The cutoff frequency of the red semiconductor laser device 20 when the capacitance value generated in the current blocking layer 10c is about 1/5 or less of the capacitance value generated in the first current blocking layer 20c is not provided with the current blocking layer 10c. It is only about 10% lower than the cut-off frequency.

  In general, the cutoff frequency of a semiconductor laser element changes within a range of about 10% due to variations in the arrangement of the semiconductor laser elements. Therefore, if the reduction of the cutoff frequency of the red semiconductor laser element 20 is limited to about 10%, the degradation of the cutoff frequency can be almost ignored.

  Thus, by setting the thickness of the current blocking layer 10c so that the capacitance value generated in the current blocking layer 10c is about 1/5 or less of the capacitance value generated in the first current blocking layer 20c, the current The reduction in the cut-off frequency of the red semiconductor laser device 20 due to the influence of the block layer 10c is remarkably reduced. That is, the deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the current blocking layer 10c is extremely sufficiently suppressed.

  In the above description, the thickness of the current blocking layer 10c is set to a predetermined value in order to adjust the capacitance value generated in the current blocking layer 10c. However, the capacitance value generated in the current blocking layer 10c may be adjusted by setting the material, width (Y direction) and length (X direction) of the current blocking layer 10c.

  In the third embodiment, the capacitance value generated in the current blocking layer 10c is equal to or less than the capacitance value generated in the first current blocking layer 20c. Further, the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20b of the red semiconductor laser element 20 are electrically connected. This facilitates control of the driving voltages of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 and sufficiently suppresses deterioration of the high-frequency characteristics of the red semiconductor laser element 20 due to the influence of the insulating layer. .

  Furthermore, a plurality of semiconductor laser devices 500 can be simultaneously manufactured by superimposing a wafer on which a plurality of blue-violet semiconductor laser elements 10 are formed and a wafer on which a plurality of red semiconductor laser elements 20 are formed. In this case, the positional accuracy of each blue-violet semiconductor laser element 10 and each red semiconductor laser element 20 is improved. As a result, the positioning accuracy of the emission points of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is improved.

  Further, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are arranged so that the p-side pad electrode 10a and the p-side pad electrode 20a face each other. Thereby, the semiconductor layer of the blue-violet semiconductor laser element 10 and the semiconductor layer of the red semiconductor laser element 20 are close to each other, so that the emission points of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 can be brought close to each other. Thereby, when the laser light emitted from the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is transmitted through the condenser lens, aberration due to the lens can be suppressed.

  In the third embodiment, the conductive layer 33 corresponds to the conductive layer, the current block layer 10c corresponds to the first current confinement layer, and the first current block layers 20c and 30c second to the current confinement layer. Equivalent to.

(Fourth embodiment)
The semiconductor laser device according to the fourth embodiment is different in configuration and operation from the semiconductor laser device 500 according to the first embodiment in the following points.

  FIG. 15 is an external perspective view showing a semiconductor laser device according to the fourth embodiment.

  In FIG. 15, the semiconductor laser device 500 according to the fourth embodiment further includes a power supply pin 1c in addition to the semiconductor laser device 500 according to the first embodiment.

  16 is a schematic front view showing a state where the lid 4 of the semiconductor laser device 500 of FIG. 15 is removed, and FIG. 17 is a schematic top view showing a state where the lid 4 of the semiconductor laser device 500 of FIG. 15 is removed. FIG.

  As shown in FIG. 16, the conductive support member 5 integrated with the package body 3 is provided with a plurality of fusion layers H as in the semiconductor laser device 500 according to the first embodiment. The sub-substrate 31, the blue-violet semiconductor laser element 10, the insulating layer 32, and the red semiconductor laser element 20 are laminated in order.

  Also in this example, the sub-board 31 includes conductive layers 31a and 31b on the upper surface and the lower surface. A conductive layer 32 a is formed on the insulating layer 32.

  As shown in parentheses in FIG. 16, an infrared semiconductor laser element 30 may be stacked on the blue-violet semiconductor laser element 10 instead of the red semiconductor laser element 20.

  As shown in FIGS. 16 and 17, the power supply pins 1a, 1b, and 1c are electrically insulated from the package body 3 by insulating rings 1z, respectively.

  The power feed pin 1a is electrically connected to the conductive layer 31a on the sub-board 31 through the wire W4. As a result, the power supply pin 1 a is electrically connected to the p-side pad electrode 10 a of the blue-violet semiconductor laser element 10.

  The power feed pin 1b is electrically connected to the conductive layer 32a on the insulating layer 32 through the wire W1. As a result, the feed pin 1b is electrically connected to the p-side pad electrode 20a of the red semiconductor laser element 20.

  The power feed pin 1c is electrically connected to the n-side pad electrode 20b of the red semiconductor laser element 20 through the wire W2, and is electrically connected to the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 through the wire W3. It is connected. As a result, the feed pin 1 c functions as a common n-side pad electrode for the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20. That is, the cathode common connection of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is realized.

  In particular, in the fourth embodiment, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are electrically insulated from the conductive support member 5, respectively. That is, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are connected from the support member 5 in a floating state.

  By applying a voltage between the power supply pins 1a and 1c and between the power supply pins 1b and 1c, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 can be individually driven.

  FIG. 18 is a circuit diagram showing electrical wiring of a semiconductor laser device 500 according to the fourth embodiment.

  As described above, both the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are electrically insulated from the support member 5. In this case, an arbitrary voltage can be applied to the power supply pin 1c.

  For example, when the red semiconductor laser device 20 is driven, a ground potential is applied to the power feed pin 1c, and a voltage higher than the ground potential is applied to the power feed pin 1a. On the other hand, when driving the blue-violet semiconductor laser element 10 whose driving voltage is higher than that of the red semiconductor laser element 20, a negative voltage is applied to the feed pin 1c, and the same as when the red semiconductor laser element 20 is driven to the feed pin 1a. Apply voltage.

  Thus, the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 are electrically insulated from the support member 5. Further, since an arbitrary voltage can be applied to the power supply pin 1a electrically connected to the n-side pad electrodes 10b and 20b of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20, The drive voltage can be easily controlled.

  In the fourth embodiment, the n-side pad electrode 10b of the blue-violet semiconductor laser device 10 and the n-side pad electrode 20b of the red semiconductor laser device 20 are electrically connected to each other and electrically insulated from the support member 5. Has been. In this case, voltages can be applied to the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 and the n-side pad electrode 20b of the red semiconductor laser element 20, respectively.

(Fifth embodiment)
The semiconductor laser device according to the fifth embodiment is different in configuration and operation from the semiconductor laser device 500 according to the first embodiment in the following points. The appearance of the semiconductor laser device according to the fifth embodiment is the same as that of the semiconductor laser device 500 of FIG. 15, and in addition to the semiconductor laser device 500 according to the first embodiment, as in the fourth embodiment. And a power supply pin 1c.

  FIG. 19 is a schematic front view showing a state in which the lid 4 of the semiconductor laser device according to the fifth embodiment is removed, and FIG. 20 shows the lid 4 of the semiconductor laser device according to the fifth embodiment. It is a typical top view which shows the state removed.

  Similar to the semiconductor laser device 500 according to the first embodiment, the sub-substrate 31 and the blue-violet semiconductor are disposed on the conductive support member 5 integrated with the package body 3 through the plurality of fusion layers H. Laser elements 10 are sequentially stacked. Also in the fifth embodiment, the sub-board 31 includes conductive layers 31a and 31b on the upper surface and the lower surface.

An insulating layer 34 made of SiO ₂ is provided in a partial region (hereinafter referred to as a first insulating region) on the n-side pad electrode 10 b of the blue-violet semiconductor laser device 10. In the following description, the thickness of the insulating layer 34 is t34. Details of the thickness t34 of the insulating layer 34 will be described later. On the insulating layer 34, a conductive layer 34a containing Au is formed.

Furthermore, an insulating layer 35 made of SiO ₂ is provided in a partial region (hereinafter referred to as a second insulating region) on the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 excluding the first insulating region. Yes. In the following description, the thickness of the insulating layer 35 is assumed to be t35. Details of the thickness t35 of the insulating layer 35 will be described later. On the insulating layer 35, a conductive layer 35a containing Au is formed.

  The first insulating region and the second insulating region are separated from each other on the n-side pad electrode 10b. Therefore, the conductive layers 34a and 35a on the insulating layers 34 and 35 are electrically insulated.

  On the conductive layer 34a, the red semiconductor laser element 20 is bonded via the fusion layer H so that the p-side pad electrode 20a is on the support member 5 side. On the conductive layer 35a, the infrared semiconductor laser device 30 is bonded via the fusion layer H so that the p-side pad electrode 30a is on the support member 5 side.

  Here, in the fifth embodiment, the blue-violet semiconductor laser device 10 has a width of about 700 μm (Y direction) and a length of about 600 μm (X direction). The red semiconductor laser element 20 has a width (Y direction) of about 200 μm and a length (X direction) of about 600 μm. The infrared semiconductor laser element 30 has a width (Y direction) of about 200 μm and a length (X direction) of about 600 μm.

  Further, the insulating layers 34 and 35 have a width (Y direction) of about 300 μm and a length (X direction) of about 600 μm, like the insulating layer 32 of the first embodiment.

  As shown in FIGS. 19 and 20, the power supply pins 1a, 1b, and 1c are electrically insulated from the package body 3 by insulating rings 1z.

  The power feed pin 1a is electrically connected to the conductive layer 31a on the sub-substrate 31 through the wire W6. As a result, the power supply pin 1 a is electrically connected to the p-side pad electrode 10 a of the blue-violet semiconductor laser element 10.

  The power feed pin 1b is electrically connected to the conductive layer 34a on the insulating layer 34 through the wire W1. As a result, the feed pin 1b is electrically connected to the p-side pad electrode 20a of the red semiconductor laser element 20.

  The power feed pin 1c is electrically connected to the conductive layer 35a on the insulating layer 35 through the wire W4. As a result, the feed pin 1 b is electrically connected to the p-side pad electrode 30 a of the infrared semiconductor laser element 30.

  The exposed upper surface of the supporting member 5 and the n-side pad electrode 10b of the blue-violet semiconductor laser element 10 are electrically connected by a wire W2, and the exposed upper surface of the supporting member 5 and the n-side pad electrode 20b of the red semiconductor laser element 20 are connected. Are electrically connected by a wire W3, and the exposed upper surface of the support member 5 and the n-side pad electrode 30b of the infrared semiconductor laser element 30 are electrically connected by a wire W5.

  As a result, the feed pin 2 is electrically connected to the n-side pad electrode 10b of the blue-violet semiconductor laser element 10, the n-side pad electrode 20b of the red semiconductor laser element 20, and the n-side pad electrode 30b of the infrared semiconductor laser element 30. ing. That is, the cathode common connection of the blue-violet semiconductor laser element 10 and the red semiconductor laser element 20 is realized.

  By applying a voltage between the power supply pins 1 a and 2, between the power supply pins 1 b and 2, and between the power supply pins 1 c and 2, the blue-violet semiconductor laser element 10, the red semiconductor laser element 20, and the infrared semiconductor laser element 30 are changed. It can be driven individually.

  FIG. 21 is a circuit diagram showing electrical wiring of a semiconductor laser device 500 according to the fifth embodiment.

  As described above, the feed pin 2 is electrically connected to the support member 5, and the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10, the n-side pad electrode 20 b of the red semiconductor laser element 20, and the infrared semiconductor laser. The n-side pad electrode 30b of the element 30 is electrically connected.

  On the other hand, the p-side pad electrode 10 a of the blue-violet semiconductor laser element 10, the p-side pad electrode 20 a of the red semiconductor laser element 20, and the p-side pad electrode 30 a of the infrared semiconductor laser element 30 are electrically connected to the support member 5, that is, the feed pin 2. Is electrically insulated.

  Thus, in order to drive the blue-violet semiconductor laser device 10, it is necessary to apply a voltage higher than the ground potential to the power feed pin 1a with respect to the power feed pin 2. Further, in order to drive the red semiconductor laser element 20, it is necessary to apply a voltage higher than the ground potential to the power supply pin 1b with respect to the power supply pin 2. Furthermore, in order to drive the infrared semiconductor laser device 30, it is necessary to apply a voltage higher than the ground potential to the power supply pin 1c with respect to the power supply pin 2.

  As described above, in the semiconductor laser device 500 according to the fifth embodiment, the blue-violet semiconductor laser device 10 and the red semiconductor are provided by applying a voltage higher than the ground potential to any one of the power supply pins 1a, 1b, and 1c. The laser element 20 and the infrared semiconductor laser element 30 can be driven individually. As a result, the drive voltage of each semiconductor laser element can be easily controlled.

  In the fifth embodiment, the sub-substrate 31 functions as a dielectric when the blue-violet semiconductor laser device 10 is driven by an AC voltage. However, as in the first embodiment, the thickness of the sub-substrate 31 is about 200 μm, which is significantly larger than the thickness of 0.5 μm of the current blocking layer 10c. Therefore, the influence of the sub-substrate 31 on the blue-violet semiconductor laser element 10 can be almost ignored.

  On the other hand, the insulating layer 34 acts as a dielectric when the red semiconductor laser device 20 is driven by an AC voltage. In the fifth embodiment, the shape of the first current blocking layer 20c is the same as the shape of the first current blocking layer 20c described in the first embodiment. The shape of the insulating layer 34 is the same as the shape of the insulating layer 32 described in the first embodiment.

  Accordingly, the thickness t34 of the insulating layer 34 is preferably set to 0.23 μm or more, and more preferably set to 0.46 μm or more. Furthermore, it is very preferable that the thickness t34 of the insulating layer 34 is set to 1.20 μm or more.

  On the other hand, the insulating layer 35 acts as a dielectric when the infrared semiconductor laser device 30 is driven by an AC voltage. In the fifth embodiment, the shape of the first current blocking layer 30c is the same as the shape of the first current blocking layer 20c described in the first embodiment. The shape of the insulating layer 35 is the same as the shape of the insulating layer 32 described in the first embodiment.

  Therefore, the thickness t35 of the insulating layer 35 is preferably set to 0.23 μm or more, and more preferably set to 0.46 μm or more. Furthermore, the thickness t35 of the insulating layer 35 is very preferably set to 1.20 μm or more.

  In the fifth embodiment, the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser device 20 and the capacitance value generated in the first current blocking layer 30c of the infrared semiconductor laser device 30 are substantially equal. The same case is explained.

  However, when the capacitance values generated in the first current blocking layers 20c and 30c are greatly different from each other, the thicknesses t34 and t35 may be set according to the capacitance values.

  In the fifth embodiment, the red semiconductor laser device 20 and the infrared semiconductor laser device 30 may be fabricated on the same substrate. In this case, since the red semiconductor laser element 20 and the infrared semiconductor laser element 30 have a monolithic structure, the accuracy of the interval between the red emission point and the infrared emission point of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 is remarkably increased. Can be improved.

  A semiconductor laser device 500 according to the fifth embodiment includes a blue-violet semiconductor laser element 10, a red semiconductor laser element 20, and an infrared semiconductor laser element 30. Thereby, the semiconductor laser device 500 can emit laser light having three types of wavelengths.

  In the fifth embodiment, the insulating layers 34 and 35 correspond to insulating layers, and the conductive layers 34a and 35a correspond to conductive layers.

(Sixth embodiment)
The semiconductor laser device according to the sixth embodiment differs in configuration and operation from the semiconductor laser device 500 according to the fifth embodiment in the following points. The appearance of the semiconductor laser device according to the sixth embodiment is the same as that of the semiconductor laser device 500 of FIG. 15 as in the fifth embodiment.

  FIG. 22 is a schematic front view showing a state in which the lid 4 of the semiconductor laser device according to the sixth embodiment is removed, and FIG. 23 shows the lid 4 of the semiconductor laser device according to the sixth embodiment. It is a typical top view which shows the state removed.

  As shown in FIG. 22, a conductive fusion layer H is formed on the conductive support member 5 integrated with the package body 3. On the fusion layer H, the blue-violet semiconductor laser device 10 is bonded so that the n-side pad electrode 10b is on the support member 5 side.

  In the sixth embodiment, the blue-violet semiconductor laser device 10 has a width (Y direction) of about 800 μm and a length (X direction) of about 600 μm.

The p-side pad electrode 10a of the blue-violet semiconductor laser device 10 is formed in a partial region of the current blocking layer 10c formed in the semiconductor layer. Similar to the third embodiment, the ridge portion Ri of the blue-violet semiconductor laser device 10 is formed under the p-side pad electrode 10a, and the current blocking layer 10c is made of SiO ₂ .

  In the sixth embodiment, the partial region where the p-side pad electrode 10a is formed is about 1/4 of the size of the entire blue-violet semiconductor laser device 10 in the XY plane. For example, the p-side pad electrode 10a has a width (Y direction) of about 200 μm and a length (X direction) of about 600 μm.

  On the XY plane, conductive layers 36 and 37 containing Au are formed in other regions of the current blocking layer 10c in a state of being separated from the p-side pad electrode 10a. The formation region of the conductive layer 36 in the XY plane is referred to as a first conductive layer formation region. The formation region of the conductive layer 37 in the XY plane is referred to as a second conductive layer formation region. In the Y direction, the p-side pad electrode 10a is located between the first and second conductive layer formation regions.

  The conductive layers 36 and 37 both have a width (Y direction) of about 300 μm and a length (X direction) of about 600 μm.

  On the conductive layer 36, the red semiconductor laser element 20 is bonded via a fusion layer H made of AuSn so that the p-side pad electrode 20a is on the support member 5 side.

  On the conductive layer 37, the infrared semiconductor laser element 30 is bonded via a fusion layer H made of AuSn so that the p-side pad electrode 30a is on the support member 5 side.

  As shown in FIGS. 22 and 23, the power supply pins 1a, 1b, and 1c are electrically insulated from the package body 3 by insulating rings 1z, respectively.

  The power feed pin 1a is electrically connected to the conductive layer 37 through the wire W5. Thereby, the power feed pin 1 a is electrically connected to the p-side pad electrode 30 a of the infrared semiconductor laser element 30.

  The power feed pin 1b is electrically connected to the conductive layer 36 through the wire W1. As a result, the feed pin 1b is electrically connected to the p-side pad electrode 20a of the red semiconductor laser element 20.

  The power feed pin 1c is electrically connected to the p-side pad electrode 10a of the blue-violet semiconductor laser device 10 through the wire W3.

  The exposed upper surface of the support member 5 and the n-side pad electrode 20b of the red semiconductor laser element 20 are electrically connected by a wire W2. The exposed upper surface of the support member 5 and the n-side pad electrode 30b of the infrared semiconductor laser element 30 are electrically connected by a wire W4.

  In the sixth embodiment, the n-side pad electrode 10 b of the blue-violet semiconductor laser element 10 is electrically connected to the support member 5 via the fusion layer H. As a result, the feed pin 2 is electrically connected to the n-side pad electrode 10b of the blue-violet semiconductor laser element 10, the n-side pad electrode 20b of the red semiconductor laser element 20, and the n-side pad electrode 30b of the infrared semiconductor laser element 30. ing. That is, the cathode common connection of the blue-violet semiconductor laser element 10, the red semiconductor laser element 20, and the infrared semiconductor laser element 30 is realized.

  By applying a voltage between the power supply pins 1c and 2, between the power supply pins 1b and 2, and between the power supply pins 1a and 2, the blue-violet semiconductor laser element 10, the red semiconductor laser element 20, and the infrared semiconductor laser element 30 are changed. It can be driven individually. The electrical wiring of the semiconductor laser device 500 according to the sixth embodiment is the same as that in FIG. In FIG. 21, the reference numerals of the power supply pins according to the sixth embodiment are shown in parentheses. Thus, also in the semiconductor laser device 500 according to the sixth embodiment, it is easy to control the drive voltage of each of the semiconductor laser elements 10, 20, and 30.

  When the blue-violet semiconductor laser device 10 is driven by an alternating voltage, a partial region of the current block layer 10c where the p-side pad electrode 10a is formed functions as a dielectric.

  FIG. 24 is a diagram showing the relationship between the capacitance value generated in the current blocking layer 10c when the blue-violet semiconductor laser device 10 in FIG. 22 is driven and the thickness of the current blocking layer 10c. In FIG. 24, the vertical axis represents the capacitance value, and the horizontal axis represents the thickness of the current blocking layer 10c. As described above, the capacitance value generated in the current blocking layer 10a in the partial region changes according to the thickness of the current blocking layer 10c. In the sixth embodiment, the thickness of the current blocking layer 10c varies depending on the thickness of first current blocking layers 20c and 30c described later.

  When the red semiconductor laser device 20 is driven by an AC voltage, the current blocking layer 10c in the first conductive layer forming region acts as a dielectric. In the sixth embodiment, the shape of the first current blocking layer 20c is the same as the shape of the first current blocking layer 20c described in the first embodiment. The current blocking layer 10 c in the first conductive layer formation region has the same width and length as the conductive layer 36.

  Further, when the red semiconductor laser element 30 is driven by an AC voltage, the current blocking layer 10c in the second conductive layer forming region acts as a dielectric. In the sixth embodiment, the shape of the first current blocking layer 30c is the same as the shape of the first current blocking layer 30c described in the first embodiment. The current block layer 10 c in the second conductive layer formation region has the same width and length as the conductive layer 37.

  Therefore, the thickness of the current blocking layer 10c is preferably set to 0.23 μm or more based on FIG. 6, and more preferably set to 0.46 μm or more. Furthermore, the thickness of the current blocking layer 10c is very preferably set to 1.20 μm or more.

  In particular, when the thickness of the current blocking layer 10c is set to 0.23 μm or more, the capacitance value generated in the current blocking layer 10c when driving the red semiconductor laser element 20 and the infrared semiconductor laser element 30 is about It can be 20 pF or less. Thereby, deterioration of the high frequency characteristics of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 due to the influence of the current blocking layer 10c is sufficiently suppressed.

  Even when the blue-violet semiconductor laser device 10 is driven, the capacitance value generated in the current blocking layer 10c is about 20 pF or less, so that the high-frequency characteristics of the blue-violet semiconductor laser device 10 are further improved. In particular, since the cutoff frequency of the blue-violet semiconductor laser element 10 is set to 600 MHz or higher, good performance can be obtained when the semiconductor laser device 500 is used in an optical pickup device or the like.

  When the thickness of the current block layer 10c is set to 0.46 μm or more, the capacitance value generated in the current block layer 10c when driving the red semiconductor laser element 20 and the infrared semiconductor laser element 30 should be about 10 pF or less. Can do. Thereby, deterioration of the high frequency characteristics of the red semiconductor laser device 20 and the infrared semiconductor laser device 30 due to the influence of the current blocking layer 10c is more sufficiently suppressed.

  Further, when the thickness of the current blocking layer 10c is set to 1.20 μm or more, the capacitance value generated in the current blocking layer 10c when driving the red semiconductor laser element 20 and the infrared semiconductor laser element 30 should be about 4 pF or less. Can do. Thereby, deterioration of the high frequency characteristics of the red semiconductor laser device 20 and the infrared semiconductor laser device 30 due to the influence of the current blocking layer 10c is extremely sufficiently suppressed.

  Even when the blue-violet semiconductor laser device 10 is driven, the capacitance value generated in the current blocking layer 10c is about 4 pF or less, so that the high-frequency characteristics of the blue-violet semiconductor laser device 10 are remarkably improved. Thereby, good performance can be obtained when the semiconductor laser device 500 is used in an optical pickup device or the like.

  In the sixth embodiment, the capacitance value generated in the first current blocking layer 20c of the red semiconductor laser device 20 and the capacitance value generated in the first current blocking layer 30c of the infrared semiconductor laser device 30 are substantially equal. The same case is explained.

  However, when the capacitance values generated in each of the first current blocking layers 20c and 30c are greatly different from each other, the thickness may be set according to each.

  As described above, in the semiconductor laser device 500 according to the sixth embodiment, the p-side pad electrode 10a of the blue-violet semiconductor laser element 10 and the p-side pad electrode of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 are used. It arrange | positions so that 20a, 30a may oppose.

  As a result, the emission points of the blue-violet semiconductor laser element 10, the red semiconductor laser element 20, and the infrared semiconductor laser element 30 can be arranged on substantially the same straight line in the YZ plane.

  In the sixth embodiment, the red semiconductor laser device 20 and the infrared semiconductor laser device 30 may be fabricated on the same substrate. In this case, since the red semiconductor laser element 20 and the infrared semiconductor laser element 30 have a monolithic structure, the accuracy of the interval between the red emission point and the infrared emission point of the red semiconductor laser element 20 and the infrared semiconductor laser element 30 is remarkably increased. Can be improved.

  In the sixth embodiment, the conductive layers 36 and 37 correspond to conductive layers, the current block layer 10c corresponds to a first current confinement layer, and the first current block layers 20c and 30c correspond to a second current confinement. Corresponds to the layer.

  INDUSTRIAL APPLICABILITY The present invention can be used for an optical recording medium driving device that supports high speed information processing and large capacity.

1 is an external perspective view showing a semiconductor laser device according to a first embodiment. FIG. 2 is a schematic front view showing a state where a lid of the semiconductor laser device of FIG. 1 is removed; FIG. 2 is a schematic top view showing a state where a lid of the semiconductor laser device of FIG. 1 is removed. It is a circuit diagram which shows the electrical wiring of the semiconductor laser apparatus which concerns on 1st Embodiment. It is an equivalent circuit diagram for demonstrating the effect | action as a dielectric of the sub-board | substrate of FIG. 2, and an insulating layer. It is a figure which shows the relationship between the capacitance value generate | occur | produced in an insulating layer at the time of the drive of the red semiconductor laser element of FIG. 2, and the thickness of an insulating layer. It is typical sectional drawing for demonstrating the detail of the structure of a blue-violet semiconductor laser element. It is typical sectional drawing for demonstrating the detail of the structure of a red semiconductor laser element. It is typical sectional drawing for demonstrating the detail of the structure of an infrared semiconductor laser element. It is a typical front view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 2nd Embodiment, It is a typical top view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 2nd Embodiment. It is an equivalent circuit diagram for demonstrating the effect | action as a dielectric material of the insulating layer of FIG. It is a typical front view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 3rd Embodiment, It is a typical top view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 3rd Embodiment. It is an external appearance perspective view which shows the semiconductor laser apparatus which concerns on 4th Embodiment. FIG. 16 is a schematic front view showing a state in which the lid of the semiconductor laser device of FIG. 15 is removed; FIG. 16 is a schematic top view showing a state in which the lid of the semiconductor laser device of FIG. 15 is removed. It is a circuit diagram which shows the electrical wiring of the semiconductor laser apparatus which concerns on 4th Embodiment. It is a typical front view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 5th Embodiment, It is a typical top view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 5th Embodiment. It is a circuit diagram which shows the electrical wiring of the semiconductor laser apparatus which concerns on 5th Embodiment. It is a typical front view showing the state where the lid of the semiconductor laser device concerning a 6th embodiment was removed, It is a typical top view which shows the state which removed the cover body of the semiconductor laser apparatus which concerns on 6th Embodiment. It is a figure which shows the relationship between the capacitance value which generate | occur | produces in a current block layer at the time of the drive of the blue-violet semiconductor laser element of FIG. 22, and the thickness of a current block layer. 10 is a schematic diagram showing a semiconductor laser device described in Patent Document 1. FIG. FIG. 26 is a circuit diagram showing electrical wiring of the semiconductor laser device of FIG. 25.

Explanation of symbols

1s n-GaN substrate 5X n-GaAs substrate 5 support member 10 blue-violet semiconductor laser element 10a p-side pad electrode 10b n-side pad electrode 10c current blocking layer 20 red semiconductor laser element 20a p-side pad electrode 20b n-side pad electrode 20c first 1 current blocking layer 30 infrared semiconductor laser element 30a p-side pad electrode 30b n-side pad electrode 30c first current blocking layer 32 insulating layer 32a conductive layer 33 conductive layer 34, 35 insulating layer 34a, 35a conductive layer

Claims (10)

A conductive support member;
An insulating layer;
A conductive layer formed on one surface of the insulating layer;
A first semiconductor layer formed on a first substrate; a first one electrode formed on the first semiconductor layer; and a first other electrode formed on the first substrate, A first semiconductor laser element that emits light of a wavelength of
A second semiconductor layer formed on a second substrate; a second one electrode formed on the second semiconductor layer; and a second other electrode formed on the second substrate, A second semiconductor laser element that emits light of a wavelength of
The second semiconductor layer includes a current confinement layer that confines a current flowing from the second one electrode to the second other electrode,
The first semiconductor laser element is provided on the support member such that the first one electrode is positioned on the support member side;
The insulating layer and the conductive layer are sequentially provided on the first other electrode of the first semiconductor laser element,
The second semiconductor laser element is provided on the conductive layer so that the second one electrode is electrically connected to the conductive layer;
The second other electrode is electrically connected to the first other electrode;
A semiconductor laser device, wherein a capacitance value generated in the insulating layer is equal to or less than a capacitance value generated in the current confinement layer. 2. The semiconductor laser device according to claim 1, wherein a capacitance value generated in the insulating layer is 1/5 or less of a capacitance value generated in the current confinement layer. A conductive support member;
An insulating layer;
A conductive layer formed on one surface of the insulating layer;
A first semiconductor layer formed on a first substrate; a first one electrode formed on the first semiconductor layer; and a first other electrode formed on the first substrate, A first semiconductor laser element that emits light of a wavelength of
A second semiconductor layer formed on a second substrate; a second one electrode formed on the second semiconductor layer; and a second other electrode formed on the second substrate, A second semiconductor laser element that emits light of a wavelength of
The first semiconductor layer includes a first current confinement layer that confines a current flowing from the first one electrode to the first other electrode,
The second semiconductor layer includes a second current confinement layer that confines a current flowing from the second one electrode to the second other electrode,
The first semiconductor laser element is provided on the support member such that the first other electrode is positioned on the support member side;
The insulating layer and the conductive layer are sequentially provided on the first one electrode of the first semiconductor laser element,
The second semiconductor laser element is provided on the conductive layer so that the second one electrode is electrically connected to the conductive layer;
The second other electrode is electrically connected to the first other electrode;
2. A semiconductor laser device according to claim 1, wherein a capacitance value generated in the insulating layer is equal to or smaller than a smaller one of the capacitance values generated in the first current confinement layer and the second current confinement layer. The capacitance value generated in the insulating layer is 1/5 or less of the smaller one of the capacitance values generated in the first current confinement layer and the second current confinement layer. Item 4. The semiconductor laser device according to Item 3. 5. The semiconductor laser device according to claim 3, wherein a capacitance value generated in the insulating layer is about 10 pF or less. A conductive support member;
A conductive layer;
A first semiconductor layer formed on a first substrate; a first one electrode formed on the first semiconductor layer; and a first other electrode formed on the first substrate, A first semiconductor laser element that emits light of a wavelength of
A second semiconductor layer formed on a second substrate; a second one electrode formed on the second semiconductor layer; and a second other electrode formed on the second substrate, A second semiconductor laser element that emits light of a wavelength of
The first semiconductor layer includes an insulating first current confinement layer that confines a current flowing from the first one electrode to the first other electrode,
The second semiconductor layer includes a second current confinement layer that confines a current flowing from the second one electrode to the second other electrode,
The conductive layer is formed in a predetermined region of the first current confinement layer so as to be insulated from the first one electrode;
The first semiconductor laser element is provided on the support member such that the first other electrode is positioned on the support member side;
The second semiconductor laser element is provided on the conductive layer so that the second one electrode is electrically connected to the conductive layer;
The second other electrode is electrically connected to the first other electrode;
A semiconductor laser device, wherein a capacitance value generated in the first current confinement layer immediately below the conductive layer is equal to or less than a capacitance value generated in the second current confinement layer. 7. The semiconductor laser device according to claim 6, wherein a capacitance value generated in the first current confinement layer immediately below the conductive layer is 1/5 or less of a capacitance value generated in the second current confinement layer. . 8. The semiconductor laser device according to claim 1, further comprising a sub-substrate having a predetermined thickness inserted between the support member and the first semiconductor laser element. The semiconductor laser device according to claim 1, wherein the first semiconductor laser element includes a nitride-based semiconductor. 10. The semiconductor laser device according to claim 1, wherein the first and second other electrodes are electrically connected to each other and electrically insulated from the support member.

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