JP2003092450A - Semiconductor light emitting unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light emitting unit improved to suppress a change of a far field pattern when an aging test is executed. SOLUTION: A semiconductor light emitting element chip has a nitride compound semiconductor substrate 105, and a nitride compound semiconductor layer 106 provided on the substrate 105. The chip is mounted on the sub-mount 103 so that a laser beam emitting end face of the chip is deviated forward in a range of 5 μm<=L<=100 μm from the end face of the sub-mount 103, (wherein L is a deviated distance).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to semiconductor light emitting devices, and more particularly to a semiconductor light emitting device having a laser chip using a nitride compound.

[0002]

2. Description of the Related Art At present, a laser chip including an active layer made of a nitride semiconductor represented by GaN, InN, AlN and their mixed crystal semiconductors has been developed. Also,
A semiconductor laser device equipped with this laser chip has been prototyped. In the semiconductor laser device, the temperature of the light emitting part rises due to the heat generated in the laser chip during its operation,
It is well known that the characteristics are deteriorated.

Therefore, the laser chip must be mounted on the stem with good thermal conductivity. JP-A-11-340
Japanese Patent No. 571 describes a semiconductor laser device using a GaN substrate. However, there is no detailed description on the mount in this publication.

[0004]

An aging test was carried out by mounting a semiconductor laser chip using a GaN substrate. Here, the engine test is an APC drive (changing the drive current (Iop) so that the light output is constant), 5 mW (light output), an ambient temperature of 60 ° C., and a semiconductor laser device for each drive time. Is to investigate the characteristics of.

At this time, it has been found that the far field pattern (FFP) of the semiconductor laser chip changes greatly in about tens of hours. A semiconductor laser device
When used as a pickup for a device such as a VD, when the FFP changes in this way, the signal of the disk cannot be accurately tracked and an erroneous signal is read, which is a very problem.

The present invention has been made to solve the above problems, and provides an improved semiconductor light emitting device capable of suppressing a change in FFP when an aging test is performed. With the goal.

[0007]

A semiconductor light emitting device according to a first aspect is a semiconductor light emitting element chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and the semiconductor light emitting device. And a submount on which the element chip is mounted. The laser light emitting end surface of the semiconductor light emitting device chip, from the end surface of the submount,
In order to shift forward within the range of 5 μm ≦ L ≦ 100 μm,
The semiconductor light emitting element chip is mounted on the submount (where L is a displaced distance).

In the semiconductor light emitting device according to the second aspect, a semiconductor light emitting element chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and the semiconductor light emitting element chip are mounted. And a stem. The semiconductor light emitting device chip is mounted on the stem such that the laser light emitting end face of the semiconductor light emitting device chip is displaced forward from the end face of the stem in the range of 5 μm ≦ L ≦ 100 μm (wherein, L is the displaced distance).

In a semiconductor light emitting device according to a third aspect, a semiconductor light emitting device chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and the semiconductor light emitting device chip are mounted. And a submount. The corner of the side of the submount that contacts the laser light emitting end face of the semiconductor light emitting element chip is chamfered and scraped off. The laser light emitting end face of the semiconductor light emitting device chip is located in front of a distance L satisfying the following inequality from a portion where the nitride compound semiconductor substrate and the submount are in contact with each other. 5 μm ≦ L
≦ 100 μm.

In a semiconductor light emitting device according to a fourth aspect, a semiconductor light emitting device chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and the semiconductor light emitting device chip are mounted. And a stem. The corner of the stem on the side in contact with the laser light emitting end face of the semiconductor light emitting element chip is chamfered and scraped off. The laser light emitting end face of the semiconductor light emitting device chip has a distance L that satisfies the following inequality from a portion where the nitride compound semiconductor substrate and the stem are in contact with each other,
It is located in the front. 5 μm ≦ L ≦ 100 μm.

The semiconductor light emitting device according to the fifth aspect is the first
In the semiconductor light emitting device according to the above aspect, the semiconductor light emitting element chip is mounted on the submount such that the nitride compound semiconductor layer side of the semiconductor light emitting element chip is in contact with the submount.

The semiconductor light emitting device according to the sixth aspect is the second
In the semiconductor light emitting device according to the aspect, the semiconductor light emitting element chip is mounted on the stem such that the nitride compound semiconductor layer side of the semiconductor light emitting element chip is in contact with the stem.

The semiconductor light emitting device according to the seventh aspect is the third light emitting device.
In the semiconductor light emitting device according to the above aspect, the semiconductor light emitting element chip is mounted on the submount such that the nitride compound semiconductor layer side of the semiconductor light emitting element chip is in contact with the submount.

A semiconductor light emitting device according to an eighth aspect is the fourth aspect.
In the semiconductor light emitting device according to the aspect, the semiconductor light emitting element chip is mounted on the stem such that the nitride compound semiconductor layer side of the semiconductor light emitting element chip is in contact with the stem.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment FIG. 1 is a side view of a semiconductor light emitting device according to the first embodiment. Note that wire connections and the like are omitted for simplification of the drawing.

Referring to FIG. 1, a nitride-based semiconductor laminate 106 is formed on an n-type GaN substrate 105. On the back surface of the n-type GaN substrate 105 (the surface on which the nitride semiconductors are not stacked), an n electrode (not shown) is formed. A p-electrode 107 is provided on the nitride-based semiconductor laminate 106. The above is the basic configuration of the semiconductor laser chip used in the semiconductor laser device according to the first embodiment, and the details thereof will be described later.

The laser chip is a submount 103.
The semiconductor laser chip is placed on the submount 103 and fixed and stacked with the solder 104 interposed between the submount and the n-electrode formed on the back surface of the laser chip. The submount 103 is also a conductive adhesive 10
It is fixed to the stem 101 by 2. At this time,
solder 104 between the n-electrode and the submount 103,
The solder (conductive adhesive 102) between the submount 103 and the stem 101 may be made of the same material or different materials without any problem.

FIG. 2 is a schematic view of the semiconductor laser chip used in this embodiment as seen from the end face.

This figure shows the semiconductor laser chip before it is mounted on the submount 103.

Referring to FIG. 2, the semiconductor laser chip is
In order from the n-type GaN substrate 105, an AlGaInN buffer layer 201, an n-AlGaInN contact layer 202,
n--AlGaInN cladding layer 203, n-AlGa
InN guide layer 204, AlGaInN multiple quantum well active layer 205, p-AlGaInN guide layer 206, p-
AlGaInN clad layer 207, p-AlGaInN
The contact layer 208 is laminated and configured.

The p-clad layer 207 and the p-contact layer 208 are provided with striped ridges extending in the cavity direction, and the ridge portion is provided between the p-electrode 107 and the nitride-based semiconductor laminate. Except the insulating film 210
Is provided.

As described above, the semiconductor laser chip used in this embodiment has a so-called ridge stripe structure. Furthermore, on the back side of the semiconductor laser chip,
The n-electrode 211 is formed. Further, the end face of the semiconductor laser chip is coated with HR or AR for the purpose of controlling the reflectance of the end face of the resonator.

A method of manufacturing the semiconductor laser device according to the present embodiment will be described below with reference to FIGS. 1 and 2.

First, a large number of unit structures of individual semiconductor laser chips as shown in FIG. 2 are formed on the n-type GaN substrate 105 by appropriately applying the process used for manufacturing semiconductor laser chips. A semiconductor laser wafer was obtained. Since such a process of obtaining a wafer is a well-known technique, its detailed description is omitted. In the present embodiment, the thickness of n-type GaN substrate 105 was 350 μm.

Next, a part of the substrate is removed from the back surface side of the n-type GaN substrate 105 by polishing or etching, and the thickness of the wafer is adjusted to a thickness of usually 40 to 200 μm.

In the present embodiment, the thickness of the wafer was adjusted to 120 μm using a grinder, and then adjusted to 100 μm using a polisher. Next, on the back surface of the wafer,
The electrode 211 was formed. Here, the layer structure of the n-electrode was Ti / Al / Mo / Au in the order from the substrate side, and the thickness of each was 300/1500/80 / 1500Å.

The Ti / Al layer is a layer for forming an ohmic contact with the n-GaN substrate, and Mo on the layer is Au and A.
The block layer for preventing the contamination of l, Au is a layer for being mixed with the solder 104 at the time of mounting to firmly mount the semiconductor laser chip.

Then, the wafer was divided into individual semiconductor laser chips by a chip dividing step. This step was performed as follows.

The wafer obtained above was placed on the stage with the back side facing upward, the scratching position was aligned using an optical microscope, and a scribe line was placed at the diamond point on the back surface of the wafer (GaN substrate). At this time, the case where the scribe line was inserted in a wavy line was the best and the most accurate cracking.

Then, an appropriate force was applied to the wafer to divide the wafer along the scribe lines to produce individual semiconductor laser chips as shown in FIG.
Although the chip dividing step has been described here by the scribing method, alignment can be similarly performed as long as a method of dividing the chip by inserting a scratch, a groove, or the like from the back surface side of the substrate can be used. Needless to say, the same effect can be obtained.

As another method, a dicing method in which a wire saw or a thin plate blade is used for scratching or cutting, irradiation heating with laser light such as an excimer laser and subsequent rapid cooling generate cracks in the irradiation portion, which are scribe lines. Similarly, the chip dividing step can be performed by using a laser scribing method, a laser ablation method or the like in which a laser beam having a high energy density is irradiated to evaporate this portion and grooving is performed.

The chip size was taken out in the range of 350 mm to 1.5 mm in the cavity length direction. Also, in the direction perpendicular to the cavity length, 200 μm to 700 μm
It was taken out in the range of m.

Next, the semiconductor laser chip was mounted on the submount by the die bonding method. This step was performed as follows.

First, the submount 103 shown in FIG.
Then, the solder 104 was formed. Here, a submount made of Cu was used. A Ni film / Au film is sequentially plated on the surface of the Cu submount 103. AuSn was used for the solder 104, and the invention after coating was about 1 to 20 μm. The solder may be previously formed into a film by coating as described above, or another film forming method such as a vapor deposition method, a sputtering method, a printing method, or a plating method may be used. However, when the solder is particularly soft at room temperature, as in the case of a solder containing In or Sn as a main component, it was preferable to use a coating method with extremely high productivity.

In the present embodiment, AuSn is used as the solder, but PbSn, In and a material containing no lead are used.
Mainly AgCu, Sn, Cu, Bi, Ag, Cu, I
It may be a material containing n, Ge or the like. Most of the above-mentioned materials have a melting point of about 150 to 120 ° C., and therefore, when mounting, it is necessary to heat to a temperature higher than this melting point. Therefore, in the present embodiment, the submount 103 is heated to a temperature slightly higher than the melting point of the solder of about 300 ° C., and when the solder is melted, the semiconductor laser chip obtained above is placed with the substrate side down, Further, while appropriately applying a load, the temperature is maintained for about 1 minute,
The electrode and the solder 104 were well blended. This allows
The Au layer on the outermost surface of the n-electrode is dissolved in the solder to form an alloy with the solder material. After that, the submount was cooled, and when the solder was solidified, this step was finished. Although the solder is provided on the submount side before this step here, it may be provided on the semiconductor laser chip side.

Here, as shown in FIG. 1, the end face of the semiconductor laser chip with respect to the end face of the submount 103 is
Mounted by shifting 10 μm forward. Letting the displaced distance be L, in this case, L = + 10 μm. Normally, the end face of the semiconductor laser chip is attached to the submount 103
The semiconductor laser device was manufactured through the above procedure of mounting at the same position as the end face of the.

As a comparative example of the semiconductor laser device of the present invention, the end face of the semiconductor laser chip is attached to the submount 103.
20 semiconductor laser devices mounted at almost the same position as the end face of the device were manufactured, and APC driving (changing the drive current (Iop) so as to keep the light output constant) was performed at 5 mW (light output) at an ambient temperature of 60 ° C. The aging test was carried out by driving with. At this time, as a result of measuring the far field pattern (FFP) of the semiconductor laser chip after 100 hours, a semiconductor laser chip showing an FFP different from the initial FFP was found, and the yield at this time was 30%.

When the semiconductor laser device is used as a pickup for a device such as a DVD, if the FFP changes in this way, the signal of the disk cannot be accurately tracked and an erroneous signal is read, which is extremely high. It's a problem.

On the other hand, the semiconductor laser device of the present embodiment was driven by APC at 5 mW (light output) at an ambient temperature of 60 ° C., and similarly an aging test was conducted. As a result of measuring the far field pattern (FFP) of the semiconductor laser chip after 100 hours, a semiconductor laser chip showing an FFP different from the initial FFP was found, but the yield at this time was 90%. As described above, by mounting the end surface of the semiconductor laser chip with the end surface of the submount 103 shifted by 10 μm forward, the change in FFP after aging was successfully suppressed significantly. As a result of repeated research on this cause, F
A situation in which the near field pattern (NFP) is changing in the chip end surface (laser light emitting end surface) where the FP is changed, for example, a phenomenon such as a dark portion having a small emission intensity appears, and the state of the end surface is confirmed by an aging test. It seems that it has changed.

Such a phenomenon that the FFP changes due to aging becomes a problem in a semiconductor laser device using a nitride semiconductor in the active layer. This is because the active layer using such a material does not necessarily have a uniform crystal in the active layer surface, it is a non-uniform active layer with uneven composition, and carrier injection is uniform in the surface. This is because the non-luminous portion is likely to occur even on the end face. In order to suppress this change in FFP, the state of the end face is important. It is known that when a sapphire substrate is used as the substrate, sapphire does not have a cleavage property, and thus when the end face is cleaved, the roughness of the end face becomes large. Therefore, when the sapphire substrate was used, the original state of the end face was not good, and the problem that the NFP changed did not appear.

When the end surface of the semiconductor laser chip is mounted at substantially the same position as the end surface of the submount 103 as in the comparative example, a strong compressive strain from the submount is applied to the laser light emitting end surface of the semiconductor laser chip. It was found from Raman measurement that the presence of It is considered that this is because the submount is made of Cu and has a larger coefficient of thermal expansion than GaN.

The thermal expansion coefficient of Cu is 16.8 × 10 ^-6 / d
and GaN is 5.59 × 10 ⁻⁶ / deg. Further, as shown in this embodiment, the end face of the semiconductor laser chip is
It was found that when mounted by shifting 10 μm forward, the distortion of compression and extension from the submount was significantly reduced on the laser light emitting end face of the semiconductor laser chip. Furthermore, the yield in each case was plotted using the distance between the end surface of the semiconductor laser chip and the end surface of the submount 103 as a parameter.

As can be seen from FIG. 3, it was found that the influence of the distortion from the submount can be avoided by projecting it forward (L = + 5 μm) by 5 μm or more. Also, 5μ
It was found that the yield decreases when the emission end face of the semiconductor laser chip is retracted rearward from the end face of the submount or below m (when L is negative).

From the above, it was found that when the strain caused by the difference in thermal expansion coefficient between GaN and the submount is applied to the end face of the semiconductor laser chip, the state of the end face is changed by the aging test. Further, when L exceeds 100 μm, the contact area between the semiconductor laser chip and the submount becomes small, heat radiation cannot be sufficiently performed, and thermal runaway shortens the life of the semiconductor laser device. Therefore, it is considered that 5 μm ≦ L ≦ 100 μm is optimal.

The submount is made of SiC (3.7 × 1).
0 ^-6 /deg),Si(3.5×10 ^-6 / deg), even if using a material that has a smaller thermal expansion coefficient than GaN, such as polycrystalline diamond, the depending mounting position Similar results were obtained. That is,
Even when tensile strain is applied to the semiconductor laser chip, there is a problem in that the FFP greatly changes due to the aging test. By performing the mounting method and position as described in this embodiment, semiconductors can be manufactured with high yield. It has been found possible to make a laser device.

Second Embodiment The second embodiment is the same as the first embodiment except that the semiconductor laser chip is directly mounted on the stem.
In other words, without using a submount, a solder is formed on the stem of the part where the semiconductor laser chip is mounted,
Mount the tip directly on the stem. Usually the stem is C
It is assumed that the end face of the semiconductor laser chip is distorted due to the difference in thermal expansion coefficient from that of the stem, even if it is made of u or the like and is mounted as described above.

Even when mounted as in this embodiment, the same result as that shown in FIG. 3 is shown, and the end face of the semiconductor laser chip is shifted forward by 5 μm or more with respect to the end face of the submounting 103. It was found that mounting can suppress the change in FFP. Further, when L exceeds 100 μm, the contact area between the semiconductor laser chip and the submount becomes small, heat radiation cannot be sufficiently performed, and thermal runaway shortens the life of the semiconductor laser device. Therefore, 5 μm ≦ L ≦ 10
0 μm is considered optimal.

Third Embodiment This embodiment has the same basic structure as that of the first embodiment, but as shown in FIG. 4, the corner of the side of the submount contacting the emitting end face of the semiconductor laser chip is chamfered. It has been scraped off.

FIG. 4 is a side view of the semiconductor laser device according to the third embodiment. In order to simplify the figure,
Wire connections and the like are omitted.

Referring to FIG. 4, a nitride semiconductor laminated body 406 is formed on an n-type GaN substrate 405.
An n-electrode (not shown) is formed on the back surface of the n-type GaN substrate 405 (the surface on which the nitride semiconductor is not laminated), and the p-electrode is formed on the nitride-based semiconductor laminate 406. 407 is provided.

The above is the basic configuration of the semiconductor laser chip used in the semiconductor laser device of the present embodiment. The semiconductor laser chip is placed on the submount 403, the solder 404 is interposed between the submount 403 and the p electrode formed on the back surface of the semiconductor laser chip, and the semiconductor laser chip is placed on the submount 403. Fixed
It is stacked. However, as described above, the submount 403 used in the present embodiment is chamfered by chamfering the corner on the side in contact with the emitting end face of the semiconductor laser chip.

As shown in FIG. 5, the state after scraping off the corners may be rounded (a), may be cut into a rectangle (b), or may be cut linearly and obliquely. It may be provided (c), and the shape does not matter.

In FIG. 5, 501 is a submount, 502 is a solder, 503 is an n-type GaN substrate, 504 is a nitride semiconductor film, and 505 is a p-type electrode.

When the submount having such a shape is used, even if the end face of the semiconductor laser chip is mounted at the same position as the end face of the submount 501 (L = 0 μm), the problem that the FFP changes is caused. Don't get up In this case, the end face of the semiconductor laser chip floats from the submount and is not distorted by the submount. In such a case, L is the distance from the portion where the substrate is in contact with the submount, as shown in FIG. In reality, since the solder 502 exists between the substrate 503 and the submount 501, they are not in direct contact with each other, but in the present specification, they are ignored as being extremely thin, and there is no solder. The discussion is on the position where the semiconductor laser chip is placed on the submount.

Even the semiconductor laser device as shown in this embodiment shows the same result as that shown in FIG. 3, and the end face of the semiconductor laser chip is shifted forward by 5 μm or more with respect to the end face of the submount. By mounting, F
It was found that the change in FP can be suppressed. Further, when L exceeds 100 μm, the contact area between the semiconductor laser chip and the submount becomes small, heat radiation cannot be sufficiently performed, and thermal runaway shortens the life of the semiconductor laser device. Therefore, it is considered that 5 μm ≦ L ≦ 100 μm is optimal.

Fourth Embodiment In this embodiment, the basic structure of the semiconductor laser device is the same as that of the second embodiment. However, only the shape of the portion of the stem on which the semiconductor laser chip is mounted is different. The corner of the stem that is in contact with the emission end face of the semiconductor laser chip is chamfered and scraped off.

As shown in FIG. 5, in the third embodiment, 5
Although 01 is the submount, it is considered in the present embodiment that 501 in FIG. 5 is an enlarged view of the stem portion on which the semiconductor laser chip is mounted. On the stem 501,
Solder 502 is formed, and the semiconductor laser chip is mounted thereon.

As shown in FIG. 5, the state of the stem 501 after scraping off the corners may be rounded (a), may be cut into a rectangle (b), or may be linear. It may be obliquely cut off (c), and the shape does not matter. In the present embodiment, in FIG. 5, 501 is a portion of the stem on which the semiconductor laser chip is mounted, 502 is solder, and 503.
Is an n-type GaN substrate, 504 is a nitride semiconductor film, 505
Is a p-type electrode.

When the stem 501 having such a shape is used, even if the end face of the semiconductor laser chip is mounted at the same position as the end face of the stem 501 (L = 0 μm), the FFP changes. Don't get up

In this case, the end surface of the semiconductor laser chip floats from the stem 501 and is not strained by the stem. In such a case, L is the distance from the portion where the substrate is in contact with the stem, as shown in FIG. In reality, since the solder 502 is present between the substrate 503 and the stem 501, they do not come into direct contact with each other, but in the present specification, they are neglected as being very thin, and when there is no solder, The discussion is on the position where the semiconductor laser chip is placed on the submount.

Even the semiconductor laser device as shown in this embodiment shows the same result as that shown in FIG. 3, and the end face of the semiconductor laser chip is 5 μm away from the end face of the stem.
The FFP can be mounted by shifting it forward more than m
It turned out that the change of can be suppressed.

Further, when L exceeds 100 μm, the contact area between the semiconductor laser chip and the submount becomes small, heat cannot be sufficiently dissipated, and thermal runaway shortens the life of the semiconductor laser device. Therefore, 5
It is considered that μm ≦ L ≦ 100 μm is optimal.

Fifth Embodiment In the first embodiment, the semiconductor laser chip is placed and mounted on the submount with the substrate 105 side facing down, but in the present embodiment, the semiconductor laser chip is formed with the p-electrode 107. Mount with the surface down (submount side) (junction down). As described above, by mounting on the stem with the junction down, it is possible to effectively dissipate the heat generated at the time of driving the semiconductor laser chip to the stem or the like, and it is possible to reduce the temperature rise of the semiconductor laser chip.

Here, the case where the junction down is mounted on the submount has been described, but the same effect can be obtained as described above even when the stem is directly mounted without the submount.

As a comparative example, even in the case of junction down, the end face of the semiconductor laser chip is mounted on the submount 1
20 semiconductor laser devices mounted on the same position as the end face of 03, APC drive (changing drive current (Iop) so as to keep the optical output constant), 5 mW
(Light output), an aging test was performed by driving at an ambient temperature of 60 ° C. At this time, as a result of measuring the far field pattern (FFP) of the semiconductor laser chip after 100 hours, a semiconductor laser chip showing an FFP different from the initial FFP was found, and the yield at this time was 20%, and the junction up The yield was worse than in the case.

This is because when the device is mounted with the junction down, the laser emitting end face is closer to the submount than when mounted with the junction up, so that a very large compression or tensile strain is applied. Therefore, it was found that the yield is further deteriorated because the change in FFP is more significantly affected than in the case of junction up.

Here, all of the mounting methods shown in the first to fourth embodiments are mounted by junction down as shown in the present embodiment. Also in this case, the same result as that shown in FIG. 3 was obtained in all the mounting methods shown in the first to fourth embodiments.

It has been found that the light output of spontaneous emission light emitted from the end face of the semiconductor laser chip can be reduced by setting the thickness of the GaN substrate to 150 μm or less.

Further, when L exceeds 200 μm, the contact area between the semiconductor laser chip and the submount becomes small, heat dissipation cannot be sufficiently performed, and thermal runaway shortens the life of the semiconductor laser device. Therefore, 5
It is considered that the optimum value is μm ≦ L ≦ 200 μm.

It is considered that this is because it was mounted with the junction down, so that the heat radiation was better than that of the semiconductor laser chip mounted with the junction up, so that even if the mounting position was shifted to 200 μm, it could be driven without thermal runaway. .

As described above, in the case of mounting with the junction down, the mounting position is shifted, or the stem and the submount are chamfered in the shape as shown in the above-mentioned embodiment, and the strain applied to the end face of the semiconductor laser chip. It has been found that the removal of the is very effective and is an effective means for improving the yield related to the FFP change after the aging test.

It should be considered that the embodiments disclosed herein are illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

[0074]

As described above, according to the present invention, in the case where the end surface of the semiconductor laser chip is mounted by being shifted forward with respect to the end surface of the submount within the range of 5 μm ≦ L ≦ 100 μm, the semiconductor laser chip is mounted. It was found that the distortion of compression and expansion and contraction from the submount was reduced on the laser light emitting end face. By mounting in this manner, excessive strain due to the difference in thermal expansion coefficient between the submount and the GaN substrate is reduced, and an effect of suppressing a change in FFP due to an aging test is exerted.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a semiconductor light emitting device according to a first embodiment.

FIG. 2 is a sectional view of the semiconductor laser chip according to the first embodiment.

FIG. 3 is a graph showing the yield when L is changed.

FIG. 4 is a conceptual diagram of a semiconductor laser device according to a third embodiment.

FIG. 5 is a schematic diagram of shapes of a stem and a submount according to the third embodiment.

[Explanation of symbols]

101 stem, 102 solder, 103 submount, 104 solder, 105 n-type GaN substrate, 106
Nitride-based semiconductor laminate, 107 p electrode.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shigetoshi Ito             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company F term (reference) 5F073 AA13 AA74 AA83 CA17 CB02                       CB22 EA18 FA14 FA22 HA05                       HA10

Claims (8)

[Claims] 1. A semiconductor light emitting device chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and a submount on which the semiconductor light emitting device chip is mounted, The semiconductor light emitting device chip is mounted on the submount such that the laser light emitting end face of the semiconductor light emitting device chip is displaced forward from the end face of the submount in the range of 5 μm ≦ L ≦ 100 μm (in the formula) , L
Is a shifted distance) A semiconductor light emitting device. 2. A semiconductor light emitting device chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and a stem on which the semiconductor light emitting device chip is mounted,
The semiconductor light emitting element chip is mounted on the stem such that the laser light emitting end surface of the semiconductor light emitting element chip is displaced forward from the end surface of the stem within a range of 5 μm ≦ L ≦ 100 μm ( In the formula, L is a shifted distance) A semiconductor light emitting device. 3. A semiconductor light emitting device chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and a submount on which the semiconductor light emitting device chip is mounted, The side of the submount, which is in contact with the laser light emitting end face of the semiconductor light emitting device chip, is chamfered and chamfered, and the laser light emitting end face of the semiconductor light emitting device chip is the nitride compound semiconductor substrate. A semiconductor light emitting device, which is located in front of a portion L that is in contact with the submount by a distance L that satisfies the following inequality. 5 μm ≦ L ≦ 100 μm 4. A semiconductor light emitting device chip having a nitride compound semiconductor substrate and a nitride compound semiconductor layer provided thereon, and a stem on which the semiconductor light emitting device chip is mounted,
, The side of the stem, which is in contact with the laser light emitting end face of the semiconductor light emitting device chip, is chamfered and chamfered, and the laser light emitting end face of the semiconductor light emitting device chip is the nitride-based compound. A semiconductor light emitting device, which is located in front of a portion L where the semiconductor substrate and the stem are in contact with each other by a distance L satisfying the following inequality. 5 μm ≦ L ≦ 100 μm 5. The semiconductor light emitting device according to claim 1, wherein the semiconductor light emitting element chip is mounted on the submount so that a nitride compound semiconductor layer side of the semiconductor light emitting element chip is in contact with the submount. . 6. The semiconductor light emitting device chip is mounted on the stem such that the nitride compound semiconductor layer side of the semiconductor light emitting device chip is in contact with the stem.
The semiconductor light emitting device according to claim 2. 7. The semiconductor light emitting device according to claim 3, wherein the semiconductor light emitting element chip is mounted on the submount such that a nitride compound semiconductor layer side of the semiconductor light emitting element chip is in contact with the submount. . 8. The semiconductor light emitting device chip is mounted on the stem such that the nitride compound semiconductor layer side of the semiconductor light emitting device chip is in contact with the stem.
The semiconductor light emitting device according to claim 4.