JP2985452B2 - Semiconductor laser device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold type semiconductor laser device formed by resin-encapsulating a laser diode element, and more particularly to a resin breakage prevention layer formed on a light emitting end face irradiated with a laser. .

[0002]

2. Description of the Related Art As a semiconductor laser device, a can type device in which a laser diode element 10 is soldered to a radiator 62 of a stem 61 and a cap 63 with a glass window is welded as shown in FIG. . On the other hand, as a semiconductor laser device having a low manufacturing cost and a large degree of freedom in shape, there is a resin-sealed type (mold type) proposed in Japanese Patent Application Laid-Open No. 2-125687. This resin-sealed type device is conventionally known as a light emitting device having a low light density per unit area, such as an LED, and is excellent in manufacturing cost and shape flexibility. It is. But,
This type of device has no problem when the density of emitted light is low, but when it is used for a laser diode element,
Optical damage of the sealing resin becomes a problem. For example, when a laser diode element is sealed with a transparent epoxy resin having excellent light transmittance, and a life test is performed under APC (automatic power control) operation at an ambient temperature of 60 ° C. and an optical output of 3 mW, a laser within 100 hours is obtained. The sealing resin in contact with the laser beam irradiation part (about 5 μm × 1 μm) of the diode element is damaged by light. Then, a hole in the form of a perforated mark is opened at a position corresponding to the irradiated portion of the sealing resin, and it is found that the characteristics of the laser device are deteriorated.

In order to prevent the deterioration of characteristics due to such optical damage, it has been proposed to form an end face destruction prevention layer. For details, refer to Japanese Patent Application No.
302258, one example of which is shown in FIG. Laser diode element 10 shown in FIG.
Is a laser diode element 10 having a DH structure (double heterojunction structure), on an n-type GaAs substrate 2,
An n-type cladding layer 3 made of AlGaAs (aluminum-gallium-arsenic), an active layer 4, a p-type cladding layer 5, and
And a p-type cap layer 6 made of GaAs (gallium-arsenic) , and an electrode 7 is selectively deposited on the front side of the opening of the p-type cap layer 6, while a back surface is formed on the back side of the GaAs substrate 2. Electrode 8 is applied. The light emitting end face 9 irradiated with the laser light is provided with an end face destruction prevention layer 20 made of an organic resin having a low light absorption coefficient and a high heat resistance in the wavelength band of the laser light. And FIG.
As shown in the figure, a laser diode element 10 having an end face destruction prevention layer 20 is mounted on a heat sink 71, and the periphery is sealed with a sealing resin layer 30 such as a transparent epoxy resin to obtain a mold type laser device. , Through the lead frame 72.

The thickness of the end face destruction preventing layer 20 is 5 μm.
Desirably, the high heat-resistant end face destruction preventing layer can prevent the resin in the vicinity of the light emitting end face from being decomposed. Therefore, the laser diode element 10 having the end face destruction preventing layer formed thereon
In the resin-encapsulated semiconductor laser device adopted, the thermal decomposition of the encapsulating resin is suppressed, so that the emission characteristics are stable for a long time, the reliability is high, and the manufacturing cost is easy, A semiconductor laser device having a free shape can be realized.

[0005]

One of the problems in extending the life of a semiconductor laser device employing a laser diode element having an end face destruction prevention layer as described above is that the end face destruction prevention is problematic. This is interface delamination due to the difference in thermal expansion coefficient between the layer and the sealing resin layer. For example,
The dimethylpolysiloxane ({(CH ₃ ) ₂ SiO} _n ) which is an organic material is used as a main component as an end surface breakdown prevention layer.
Rubber-like resin (hereinafter abbreviated as dimethylpolysiloxane)
When a transparent epoxy resin is used as the sealing resin, when the laser device is repeatedly turned on and off, peeling occurs due to stress generated at the interface due to a difference in thermal expansion coefficient between the end face destruction prevention layer and the resin sealing layer. . This may cause disturbances in the optical characteristics of the laser device, such as the far-field image,
In order to obtain stable performance over a long period of time, it is necessary to prevent such peeling.

As a method of preventing peeling, it is conceivable to use materials having the same coefficient of thermal expansion for the end face destruction prevention layer and the resin sealing layer. However, at present, no suitable material has been found. It is also conceivable to use a strong adhesive to firmly bond the end face destruction prevention layer and the resin sealing layer.However, it does not affect the optical system of laser light, has heat resistance, It is difficult to find a suitable material having an adhesive strength higher than that of resin.

In view of the above problems, the present invention has found a means for preventing separation between the end face destruction preventing layer and the resin sealing layer without affecting the optical system.
It is an object of the present invention to realize a semiconductor laser device that can maintain the characteristics of laser light for a long time.

[0008]

In order to solve the above-mentioned problems, the present invention focuses on the fact that a layer having a strong adhesive force is formed when energy is applied to the surface of the end face destruction preventing layer. The end face destruction prevention layer and the resin sealing layer are bonded to each other by using the adhesion layer having a strong adhesion.
That is, a laser diode element having at least one light emitting end face for irradiating a laser beam according to the present invention,
In a semiconductor laser device sealed with an encapsulating resin layer that transmits at least the laser light through an end-face destruction prevention layer made of an organic resin that transmits at least the laser light and prevents the light-emitting end face from being destroyed, At the boundary area between the layer and the sealing resin layer, at least in the radiation area on the front emission surface side where the laser light passes, an adhesion layer by high energy irradiation on the surface of the end face breakdown prevention layer is formed, I have.

In addition, an adhesive layer is formed by irradiating the surface of the end face destruction prevention layer with high energy only in the radiation area on the front emission surface side where the laser beam passes at the boundary between the end face destruction prevention layer and the sealing resin layer. It may be. Ultraviolet irradiation can be used as high energy irradiation.

[0010] Dimethylpolysiloxane can be used as the end face destruction preventing layer, a transparent epoxy resin can be used as the sealing resin, and short-wave ultraviolet rays having a wavelength of at least 200 nm or less can be used as ultraviolet rays. Further, as the short-wavelength ultraviolet ray, an ultraviolet ray having a wavelength of 184.9 nm included in the emission spectrum of the low-pressure mercury lamp and a wavelength of 253.
Ultraviolet light containing at least 7 nm ultraviolet light can be applied.

Also, such a semiconductor laser device is
An adhesion layer formed on the surface of the end face destruction prevention layer formed on the light emitting end face of the laser diode element with a sealing resin layer for sealing the laser diode element through the end face destruction prevention layer by high energy irradiation. It can be manufactured by a manufacturing method of a semiconductor laser device having a forming step.

Further, as the adhesion layer forming step, a shield irradiation step of performing high energy irradiation through a shield having an opening corresponding to a radiation area on the front emission surface side through which laser light passes may be employed. It is effective, and a metal mask or the like can be used as the shield. Furthermore, as the adhesion layer forming step, it is effective to adopt a lead frame irradiation step of performing high energy irradiation substantially perpendicularly to the lead frame on which the laser diode element is mounted from a direction opposite to the laser diode element. It is.

[0013]

According to this means, since the adhesive layer having high adhesiveness is formed in the radiation area of the end face destruction prevention layer through which the laser beam passes, the end face destruction prevention layer and the sealing resin layer are firmly adhered. You. Therefore, even if stress is generated at the boundary surface between the end surface destruction prevention layer and the sealing resin layer due to the difference in the thermal expansion coefficient in the repeated on / off operation of the semiconductor laser device, the occurrence of interfacial separation is prevented. For this reason, a semiconductor laser device with high long-term reliability in which the characteristics of laser light is maintained for a long period of time is realized.

Further, in the step of forming the adhesive layer, by limiting the range in which the adhesive layer is formed to the radiating region, the stress generated at the boundary surface due to the difference in the coefficient of thermal expansion causes the stress other than the radiating region where the adhesive layer is not formed. Since the radiation is released to the region, the distortion due to the on / off repetition does not accumulate in the radiation region, and the characteristics of the laser beam can be maintained for a long period of time.

The adhesion layer limited to such a radiation region is as follows:
It is formed by performing high energy irradiation through a shield having an opening corresponding to a radiation area on the front emission surface side of the laser diode element. In addition, by applying high-energy irradiation from the direction opposite to the laser diode element almost perpendicularly to the lead frame on which the laser diode element is mounted, an adhesion layer is formed in a limited area covering the radiation area. Is done.

[0016]

Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

[Embodiment 1] FIG. 4 is an enlarged view showing a state in which a laser diode element 10 is mounted on a semiconductor laser device according to this embodiment. This figure shows an enlarged view of the state where the laser diode element 10 attached to the lead frame 72 via the heat sink 71 is sealed by the sealing resin layer 30 made of a transparent epoxy resin. The overall configuration of this device is the same as that of the semiconductor laser device described above with reference to FIG. 3, and the same reference numerals are given and the description is omitted.

The end face destruction preventing layer 20 of the present device has a shape formed by using a coding method utilizing characteristics of an organic material. In other words, the end face destruction prevention layer 20 of the present device has a drop-like outer shape formed by a dipping method or a dropping method excellent in mass productivity, and is provided on the front emission surface side where the laser light is projected from the element 10. From the side of the lead frame 72 and the heat sink 71 on the same side as the laser emitting surface 11, the laser emitting surface 1 of the element 10 passes through the element 10.
It is stacked in a wide area over the back surface 12 of the first.

The end surface destruction preventing layer 20 is formed by first soldering the element 10 to the heat radiating plate 71 on the lead frame 72 by a junction down method and dropping about 1 mg of dimethylpolysiloxane from above the element 10. I do. Then, the apparatus to which the dimethylpolysiloxane is dropped is subjected to a heat treatment at a temperature of 150 ° C. for 5 hours to cure the dimethylpolysiloxane. In addition,
This dimethylpolysiloxane cures to a rubbery resin.
Are most desirable.

In this semiconductor laser device, the radiation surface 1 in front of the active layer 4 of the laser diode element 10
The laser light A is emitted toward 1. At the same time, the laser beam B is also emitted toward the back side 12, and this laser beam B is used to confirm the operation of the present apparatus. The thickness of the end surface breakdown prevention layer 20 formed as described above is 30 to 40 μm in the vicinity of the active layer 4 on the front radiation surface, and is several hundred μm or more in the vicinity of the rear active layer 4. I have.

Further, in the present device, an adhesion layer 21 is formed on the entire surface of the end face destruction prevention layer 20. This adhesive layer 21 is formed by ultraviolet irradiation as shown in FIG. 5 before coding the epoxy resin 30.
When the device 10 is mounted on the lead frame 72 and the curing process of the end surface destruction prevention layer 20 is completed, the lead frame 72 on which the device 10 is mounted is set in the ultraviolet irradiation device 42, and the ultraviolet light 43 is exposed to air for about 15 minutes. Is irradiated.
At this time, the adhesive layer 21 is formed in front of the element 10 by irradiating the radiation surface 11 of the element 10 with ultraviolet rays 43. The ultraviolet irradiation device 42 is a device using the low-pressure mercury lamp 41 as an ultraviolet light source. The emission spectrum of the ultraviolet light 43 has a wavelength of 253.7 nm, which is effective for decomposing ozone and generating oxygen radicals. Includes a line spectrum of mercury, such as 184.9 nm, which acts on oxygen to produce ozone. The irradiation energy density at a wavelength of 253.7 nm
10 mW / c near the element 10 mounted on
It is adjusted to m ^2.

After the adhesion layer 21 is formed on the surface of the end face destruction prevention layer 20 in the above, sealing is performed on the end face destruction prevention layer 20 with the transparent epoxy resin 30 to manufacture a semiconductor laser device. The results of a heat cycle test performed on the apparatus of this example and a conventional apparatus not subjected to ultraviolet irradiation will be described below. The test conditions are first maintained at 85 ° C. for 30 minutes. Then, it is left at room temperature for 5 minutes, further cooled to -40 ° C, and kept at that temperature for 30 minutes. After being left at room temperature again for 5 minutes,
Heat up to This is taken as one cycle, and the semiconductor laser device after 100 cycles has been
The presence / absence of interfacial separation between the dimethylpolysiloxane as the end face destruction prevention layer 20 on the side of the irradiation surface 11 in front of the transparent epoxy layer as the sealing layer 30 and the far-field image were checked. As a result, in the conventional semiconductor laser device which has not been subjected to the ultraviolet irradiation, about 10% of the characteristics of the laser beam have been deteriorated due to the interface peeling. However, in the apparatus of the present example to which the ultraviolet irradiation was performed, no peeling occurred at the interface, and therefore, the characteristic defect of the laser light, which was observed in the disorder of the far-field image, was not observed. From this test result, in the apparatus of the present example, the adhesion layer 21 was formed on the surface of the end surface destruction prevention layer 20 by the irradiation of ultraviolet rays, and strong adhesion with the sealing resin layer 30 was achieved. It can be seen that a long-life semiconductor laser device with stable laser emission characteristics was realized even when the thermal cycle accompanying the above was repeatedly applied.

Further, the surface of the dimethylpolysiloxane irradiated with ultraviolet rays of the apparatus of this embodiment irradiated with ultraviolet rays was examined by X-ray electron spectroscopy. As a result, from the surface,
₂ , functional groups such as carbonyl group, ether group and hydroxyl group were detected. These are more excellent in adhesiveness to the epoxy resin than dimethylpolysiloxane itself, and the adhesion layer 21 is formed on the surface of the end face destruction prevention layer 20 as estimated from the above test results. I was assured.

From the above, the effect of ultraviolet irradiation is estimated as follows. That is, when the surface of dimethylpolysiloxane is irradiated with ultraviolet rays, the wavelength is 253.7 nm (energy 133 kcal / mol) or the wavelength 18
Since the energy of ultraviolet light of 4.9 nm (energy: 155 kcal / mol) is larger than the bonding energy of Si—O bond, C—Si bond, or C—H bond, which is the main chemical bond of dimethylpolysiloxane, Break the bond. Further, oxygen radicals excited by the ultraviolet rays are present at a relatively high concentration in the atmosphere near the surface of dimethylpolysiloxane. Therefore, it is presumed that these oxygen radicals act on the above-mentioned broken bond, and the decomposition, oxidation and denaturation of the surface proceed.

As described above, by irradiating the surface of the end surface destruction preventing layer with ultraviolet rays and then laminating the sealing resin layer, a long-life semiconductor laser device having stable laser light characteristics can be realized. .

[Embodiment 2] FIG. 6 is an enlarged view of a semiconductor laser device according to Embodiment 2 in which a laser diode element 10 is mounted. This figure also shows, in an enlarged manner, a state in which the laser diode element 10 attached to the lead frame 72 via the heat sink 71 is sealed by the sealing resin layer 30 made of a transparent epoxy resin. The overall configuration of the present apparatus is the same as in the first embodiment, and the same reference numerals are given and the description is omitted.

A point to be noted in the apparatus of this embodiment is that the adhesive layer 2 is formed only on the laser emission region 13 near the active layer 4 on the emission surface 11 on the front emission surface side of the laser diode element 10.
1 is formed. In a semiconductor laser device, an optically important area such as a high-quality far-field image is required is only the emission surface 11 from which the laser light A is emitted. Since the back surface 12 from which the laser light B is emitted is used only for monitoring, it is not necessary to maintain optical quality. Therefore, except for the radiation surface 11, if further limited,
In areas other than the laser emission region 13 through which the laser light A passes, even if the interface between the end surface destruction prevention layer 20 and the sealing resin layer 30 is separated and the optical characteristics are deteriorated, the characteristics of the laser device still remain. Has no effect.

The apparatus of this embodiment pays attention to this point, and adheres only to the laser emission region 13 of the end face destruction prevention layer 20.
Is formed, the thermal strain caused by the thermal cycle is reduced in the region 1 without improving the adhesion in the region 13.
It is made to escape to the interface other than 3. That is, when a thermal cycle is applied, a stress is generated at the interface due to a difference in thermal expansion coefficient between the end surface destruction prevention layer 20 and the sealing resin layer 30, and thermal strain is excited. In the apparatus of the first embodiment, the end face destruction prevention layer 20 and the sealing resin layer 30 are bonded to each other by using the adhesive layer 21 having an adhesive force capable of withstanding the thermal distortion. On the other hand, in the apparatus of the present embodiment, only the laser emission region 13 is provided by the adhesion layer 21 and the end face destruction prevention layer 2 is provided.
0 and the sealing resin layer 30. Therefore, in regions other than the region 13, if thermal strain increases, interface separation occurs, so that energy related to the strain is released. Therefore, even if a thermal cycle is applied, the region 13
Does not accumulate strain and prevents interfacial delamination. As described above, in the device of this example, it is possible to further stabilize the optical characteristics, and it is possible to realize a semiconductor laser device having a longer life.

FIG. 7 shows the state of irradiation with ultraviolet rays in the process of manufacturing the apparatus of this embodiment. When irradiating the apparatus of this embodiment with ultraviolet rays, the same ultraviolet irradiation apparatus 42 as in the first embodiment is used. However, in the ultraviolet irradiation process of this example, the region of the end face destruction prevention layer 20 irradiated with ultraviolet light is limited to the laser emission region 13 using the metal mask 51. This metal mask 51 has 0.1
A hole 52 for ultraviolet transmission of mmφ is provided, and the mask 51 is set so that the hole 52 coincides with the laser emission region 13 having a length of about 250 μm and a width of about 100 μm. By irradiating ultraviolet rays 43 from above, the adhesion layer 21 can be formed only in the laser emission region 13. Note that the surface of the metal mask 51 is colored black in order to prevent stray light due to reflection or the like. The conditions of the ultraviolet rays 43 are the same as in the first embodiment.

In the above, the adhesion layer 21 was formed, sealed with a transparent epoxy resin in the same manner as in Example 1, and a thermal cycle test was performed on this device under the same conditions as in Example 1. As a result, large interfacial separation occurred on the back surface 12, but no abnormality was observed in the radiation region 13 and no deterioration in optical characteristics such as a far-field image was observed.

Further, the apparatus of this example was subjected to a more severe thermal cycle without leaving it at room temperature. In this heat cycle test, first, the temperature is maintained at 85 ° C. for 30 minutes, and then the temperature is lowered to −40 ° C. without being left at room temperature, and the temperature is maintained at −40 ° C. for 30 minutes. Then, the temperature rises to 85 ° C. without being left at room temperature again. With this cycle as one cycle, the state of the interface after 100 cycles and characteristics such as a far-field image were measured. As a result, no abnormality was observed at the interface of the radiation region, and no deterioration of the characteristics was observed. From this test result, it can be seen that the device of the present example is more stable than a device of Example 1 even with a more severe thermal cycle, and has a long life.

As described above, by limiting the range of the ultraviolet light radiated to the surface of the end face destruction preventing layer, the adhesion layer is formed only in the laser emission area, and then the sealing resin layer is laminated, whereby the laser light A semiconductor laser device having stable characteristics and a longer life can be realized.

[Embodiment 3] FIG. 8 shows an ultraviolet irradiation method according to the present embodiment, which is applied in the process of manufacturing a semiconductor laser device. Also in this example, the lead frame 7
2 uses a laser diode element 10 attached via a heat sink 71. Then, after forming an end face destruction preventing layer 20 of dimethylpolysiloxane on the laser diode element 10, an ultraviolet ray is applied to the end face destruction preventing layer 20 in order to form an adhesion layer 21 in a limited area covering the laser emission region 13. 43 is shown. The overall configuration of this apparatus is the same as that of the first and second embodiments, and the same reference numerals are given and the description is omitted.

In the method of irradiating with ultraviolet light of the present embodiment,
An ultraviolet irradiation device 42 similar to the first and second embodiments is used, but a low-pressure mercury lamp 41 is provided on a side surface of the ultraviolet irradiation device 42. Therefore, in this example, unlike the method of irradiating ultraviolet rays in Examples 1 and 2, FIG.
As shown in FIG.
Irradiation is performed from a direction perpendicular to the lead frame 72 on which the laser diode element 10 is mounted. The laser diode element 10 is connected to the lead frame 72.
On the other hand, since ultraviolet irradiation is performed with the direction set to be opposite to that of the low-pressure mercury lamp 41, the ultraviolet light 43 is irradiated to the end face destruction prevention layer 20 via the lead frame 72. The conditions of the ultraviolet ray 43, such as the emission spectrum width and the irradiation energy density, are the same as those in Examples 1 and 2.

As shown in FIG. 9, the device used in the present embodiment has a laser diode element 10 mounted on a plate-like lead frame 72 via a heat radiating plate 71.
The end surface destruction prevention layer 20 is formed on the lead frame 72 so as to cover the laser diode element 10. Here, the surface area of the lead frame 72 is large for the laser diode element 10 and also for the end face destruction prevention layer 20, and in this example, ultraviolet rays 43 are irradiated from the back side of such a device. Accordingly, the end face destruction prevention layer 20 is shaded by the lead frame 72 in the ultraviolet irradiation direction C, and thus the front emission face side of the laser diode element 10 on the end face destruction prevention layer 20 surface layer protruding from the lead end face of the lead frame 72. UV light 43 is applied only to the above. After forming the adhesion layer 21 in this manner,
As in Examples 1 and 2, sealing was performed with a transparent epoxy resin, and an apparatus was manufactured by the ultraviolet irradiation method of this example.

For the device manufactured as described above,
A heat cycle test was performed under the same conditions as in Example 2, and thereafter, the state of the interface and characteristics such as a far-field pattern were measured. As a result, no delamination of the interface between the end surface destruction prevention layer 20 and the sealing resin layer 30 in the laser emission region 13 and no deterioration in optical characteristics such as a far-field image were observed. Therefore, it can be seen that a semiconductor laser device having a stable laser emission characteristic and a long life like the second embodiment can be realized by the ultraviolet irradiation method of this embodiment. Further, in the manufacturing method of this example, the metal mask used in Example 2 is unnecessary.
For this reason, the time required for setting the metal mask can be omitted, and a long-life semiconductor laser device with stable characteristics can be manufactured more easily and inexpensively.

When the region in which the adhesion layer 21 is formed is examined by micro-area X-ray electron spectroscopy in the apparatus according to the manufacturing method of the present embodiment, the adhesion layer 21 on the front emission surface side of the laser diode element 10 is shown in FIG. As shown in FIG. 5, it was confirmed that the surface layer was formed so as to cover the surface layer of dimethylpolysiloxane, which is the end-face destruction prevention layer 20, and the range was limited to the laser emission region 13. Therefore,
Also in this example, it is considered that a semiconductor laser device showing good results in the above-mentioned thermal cycle test was obtained by the action of the adhesion layer 21 formed so as to cover the laser emission region 13.

According to the result of the X-ray electron spectroscopy for the minute area, the ultraviolet rays 4 were applied from the back side of the lead frame 72 of this example.
According to the method of irradiating the ultraviolet ray 43, the adhesive layer 21 is not limited to the leading end portion of the lead frame 72 which is directly irradiated with the ultraviolet ray 43, but also the laser radiation area 1 which is negative to the ultraviolet ray 43.
3 was formed. Laser radiation region 1 corresponding to such a geometrically shadowed portion
The reason why the adhesion layer 21 is formed on 3 is not clear. However, the effect of the ultraviolet light transmitted through the dimethylpolysiloxane and applied to the laser emission region 13 is considered. In addition, the maximum thickness of the dimethylpolysiloxane layer on the front emission surface side is as thin as about 100 μm. Is also conceivable.

As described above, by using the manufacturing method of this embodiment in which the ultraviolet irradiation is applied from the back side of the lead frame to the lead frame at a high energy substantially perpendicular to the lead frame, the end face destruction preventing layer including the laser emission region is limited. The adhesion layer can be formed in the range defined. In a semiconductor laser device in which such an adhesion layer is formed on an end surface breakdown prevention layer, stabilization of optical characteristics is achieved. Therefore, in the semiconductor laser device in which the laser diode element is attached to the lead frame, without using a shielding material such as a metal mask, the manufacturing method of the present embodiment,
A long-life semiconductor laser device with stable optical characteristics can be manufactured in a short time and at low cost.

As described above, in the first, second and third embodiments, in the resin-sealed mold type semiconductor laser device, the adhesion layer with the sealing resin layer is formed on the end face destruction preventing layer using ultraviolet rays. This makes it possible to stabilize optical characteristics and extend the life. Therefore,
A low-cost, free-form, long-life laser device can be realized.

In the first, second and third embodiments, the example in which the adhesion layer is formed by using ultraviolet rays has been described.
Needless to say, the adhesion layer can be formed even by using a high energy flow such as wire or plasma.

[0042]

As described above, according to the present invention, in a semiconductor laser device formed by resin-sealing a laser diode element, an adhesion layer is formed on the surface of an end face destruction prevention layer, and the sealing resin is formed by a thermal cycle. Prevents interfacial delamination with the layer. Therefore, the device according to the present invention is durable to a thermal cycle related to ON / OFF and the like, and can stably maintain characteristics of laser light such as a far-field image for a long time.

This adhesion layer can be easily formed by irradiating the end surface destruction prevention layer with a high energy flow such as ultraviolet rays. Therefore, even if the device has different thermal expansion coefficients of the end surface destruction prevention layer and the sealing resin layer, it can be a device having stable laser light characteristics and a long life.

Further, the area where the adhesive layer is formed is limited to only the area on the front emission surface side where the laser beam is emitted, and an area having a relatively low adhesive force is formed around the area.
It becomes possible to absorb the stress due to the thermal cycle in a region where the adhesion is low.

Therefore, it is possible to improve the durability against severe thermal cycles and to realize a semiconductor laser device having stable characteristics and a long life.

In a semiconductor laser device having a laser diode element mounted on a lead frame, in the step of forming the adhesion layer, the laser diode element is substantially perpendicular to the lead frame on which the laser diode element is mounted. By performing high-energy irradiation from the opposite direction, the adhesion layer can be easily formed in a limited area on the front emission surface side where laser light is emitted. Therefore, by such a simple method, it is possible to limit the irradiation region of the ultraviolet light, so that a semiconductor laser device having excellent optical characteristics and a long life can be manufactured at low cost.
Also, it can be manufactured in a short time. In particular, according to this manufacturing method, the number of steps can be reduced, and it can be said that this method is particularly effective for mass-produced products.

As described above, in the present invention, it is possible to improve the adhesion between the end face destruction preventing layer and the sealing resin layer by irradiating with ultraviolet rays or the like, and it is a low-cost, freely-shaped mold type semiconductor. The characteristics of the laser device can be stabilized, and a long-life device can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a laser diode element used in a semiconductor laser device according to the present invention.

FIG. 2 is a sectional view showing a configuration of the laser diode element shown in FIG.

FIG. 3 is an explanatory diagram showing a configuration of a resin-sealed mold type semiconductor laser device.

FIG. 4 is an enlarged sectional view showing the vicinity of a laser diode element attached to the semiconductor laser device according to the first embodiment of the present invention.

FIG. 5 is an explanatory view showing a step of irradiating ultraviolet rays in the manufacturing steps of the semiconductor laser device shown in FIG.

FIG. 6 is an enlarged sectional view showing the vicinity of a laser diode element attached to a semiconductor laser device according to a second embodiment of the present invention.

FIG. 7 is an explanatory view showing a step of irradiating ultraviolet rays in the manufacturing steps of the semiconductor laser device shown in FIG. 6;

FIG. 8 is an explanatory view showing a step of irradiating ultraviolet rays in the manufacturing steps of the semiconductor laser device according to the third embodiment of the present invention.

FIG. 9 is an explanatory diagram showing a configuration of a resin-sealed mold type semiconductor laser device.

FIG. 10 is a cutaway perspective view showing an outline of a conventional can type semiconductor laser device.

[Explanation of symbols]

 2 ... GaAs substrate 3 ... n-type clad layer 4 ... light-emitting layer 5 ... p-type clad layer 6 ... p-type cap layer 7 ... electrode 8 ... back electrode 10 ...・ Laser diode element 11 ・ ・ ・ Emission surface 12 ・ ・ ・ Back surface 13 ・ ・ ・ Emission area 20 ・ ・ ・ End face destruction prevention layer 21 ・ ・ ・ Adhesion layer 30 ・ ・ ・ Sealing resin layer 41 ・ ・ ・ Low pressure mercury lamp 42 ... Ultraviolet irradiation device 43 ... Ultraviolet 51 ... Metal mask 52 ... Hole for ultraviolet transmission 61 ... Stem 62 ... Heat radiator 63 ... Cap with window 71 ... Heat radiation Plate 72: Lead frame A, B: Laser light C: UV irradiation direction

──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsue Nakata, Inventor 1-1, Tanabe Nitta, Kawasaki-ku, Kawasaki, Kanagawa Prefecture Inside Fuji Electric Co., Ltd. No. 1 Fuji Electric Co., Ltd. (56) References JP-A-2-209786 (JP, A) JP-A-63-62363 (JP, A) JP-A-55-12774 (JP, A) JP-A-55- 3668 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01S 3/18 JICST file (JOIS)

Claims (11)

(57) [Claims] 1. A laser diode device having at least one light emitting end face for irradiating laser light, wherein said laser diode element has an end face destruction prevention layer made of an organic resin that transmits at least the laser light and prevents the light emitting end face from being destroyed. In a semiconductor laser device sealed with a sealing resin layer that transmits at least laser light, radiation on a front emission surface side of at least the laser light passing through a boundary surface between the end surface destruction prevention layer and the sealing resin layer. A semiconductor laser device, wherein an adhesion layer is formed in a region by high-energy irradiation on the surface of the end-face breakdown prevention layer. 2. A laser diode device having at least one light emitting end face for irradiating laser light, wherein said laser diode element has an end face destruction prevention layer made of an organic resin that transmits at least the laser light and prevents the light emitting end face from being destroyed. In a semiconductor laser device sealed with a sealing resin layer that transmits at least laser light, a radiation area on a front emission surface side of the boundary surface between the end surface destruction prevention layer and the sealing resin layer, through which the laser light passes. A semiconductor laser device, wherein an adhesive layer is formed only on the surface of the end surface destruction prevention layer by high energy irradiation. 3. The semiconductor laser device according to claim 1, wherein the high-energy irradiation is ultraviolet irradiation. 4. The end face destruction prevention layer according to claim 3, wherein the end face destruction prevention layer is a rubber-like resin containing dimethylpolysiloxane as a main component, the sealing resin is a transparent epoxy resin, and the ultraviolet light has a wavelength of at least 200 nm or less. A semiconductor laser device characterized by containing short-wavelength ultraviolet light. 5. The method according to claim 4, wherein the short-wavelength ultraviolet light has a wavelength of 1 that is included in an emission spectrum of a low-pressure mercury lamp.
A semiconductor laser device comprising at least ultraviolet light having a wavelength of 84.9 nm and ultraviolet light having a wavelength of 253.7 nm. 6. An adhesive layer with a sealing resin layer for sealing the laser diode element via the end face destruction preventing layer is formed on the surface of the end face destruction preventing layer formed on the light emitting end face of the laser diode element with high energy. A method for manufacturing a semiconductor laser device, comprising a step of forming an adhesion layer formed by irradiation. 7. The method according to claim 6, wherein the step of forming the adhesive layer includes applying the high-energy irradiation to a shield having an opening corresponding to a radiation area on a front emission surface side of the laser diode element through which laser light passes. A method of manufacturing a semiconductor laser device, wherein the method is a shielding irradiation step. 8. The method according to claim 6, wherein in the step of forming the adhesion layer, the high-energy irradiation is performed substantially perpendicularly to a lead frame to which the laser diode element is attached, from a direction opposite to the laser diode element. And a lead frame irradiation step. 9. The method for manufacturing a semiconductor laser device according to claim 6, wherein the high energy irradiation is ultraviolet irradiation. 10. The method according to claim 9, wherein the end surface destruction preventing layer is a rubber-like resin containing dimethylpolysiloxane as a main component, the sealing resin is a transparent epoxy resin, and the ultraviolet light is at least 200 nm. A method of manufacturing a semiconductor laser device, comprising a short wavelength ultraviolet light including the following wavelengths. 11. The method according to claim 9, wherein the short-wavelength ultraviolet light has a wavelength of 1 that is included in an emission spectrum of a low-pressure mercury lamp.
A method for manufacturing a semiconductor laser device, comprising at least ultraviolet light having a wavelength of 84.9 nm and ultraviolet light having a wavelength of 253.7 nm.