JP3218963B2 - Nitride semiconductor laser device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nitride semiconductor (In _XA).
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser device made of l _Y Ga _{1 -XYN} (0 ≦ X, 0 ≦ Y, X + Y ≦ 1) and a method of manufacturing the same, particularly a laser device having a resonance surface obtained by cleavage and a method of forming the resonance surface. About.

[0002]

2. Description of the Related Art As materials for light emitting devices such as LDs and LEDs, nitride semiconductors (In) having a wide bandgap semiconductor are used.
_{X Al Y Ga 1-XY N} , 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is known. This semiconductor is usually MO on a sapphire substrate.
It grows using vapor phase growth methods, such as VPE (organic metal vapor phase epitaxy) and MBE (molecular beam vapor phase epitaxy). Sapphire has a plane orientation such as an A plane, a C plane, an R plane, and an M plane, but a nitride semiconductor is exclusively grown on the C plane. In general, a nitride semiconductor wafer grown on a sapphire substrate has another GaAs, because the sapphire substrate does not have cleavage.
There is a problem that it is very difficult to form a chip as compared with a wafer having a cleavage substrate such as Si or GaP. Furthermore, since sapphire is a substance having a Mohs luminous intensity of 9 or more, even when cut with a dicer, so-called chipping such as chip breakage or chipping occurs on the cut surface, and it is difficult to obtain a chip with a flat cut surface. Was.

[0003] Under such circumstances, it is very difficult to cut a nitride semiconductor layer grown on sapphire and form a resonance surface on the cut surface. For laser devices,
It is necessary to form a resonance surface for reflecting the light of the active layer inside, and it is necessary to form the resonance surface as a flat surface having very few irregularities, that is, a mirror surface. In the case of an infrared or red laser using a GaAs substrate, a cleavage plane using the cleavage of the substrate is used as the resonance surface. However, since a nitride semiconductor wafer having a sapphire C-plane as a substrate has no cleavage property as described above, it has been almost impossible to cleave the substrate to form a resonance surface.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a nitride semiconductor laser device in which a resonance surface is formed on an end face of an active layer by cleavage, and a novel method for manufacturing the laser device. Is to do.

[0005]

We have found that only sapphire having the growth surface of a nitride semiconductor as the A-plane has a cleavage property at the R-plane, and when cleaved at the R-plane, the nitride grown on the A-plane is obtained. The present inventors have newly found that a semiconductor is cleaved in a specific direction, and have accomplished the present invention. That is, in the nitride semiconductor laser device of the present invention, a nitride semiconductor having an active layer that oscillates laser is grown on the A surface of the sapphire substrate, and the sapphire substrate is cleaved on the R surface,
A cleavage plane of the active layer which is not on the same horizontal plane as the R plane is a resonance plane.

In the laser device of the present invention, the width of the waveguide region of the active layer is limited to 20 μm or less, and the nitride semiconductor surface on which the substrate is cleaved is jagged, and the jagged surfaces are parallel to each other. It is characterized in that the inclined surface is a resonance surface. Further, the thickness of the sapphire substrate is 150
μm or less.

Further, the resonance surface is located within a range of 5 ° ± 4 ° to the right and left with respect to the R-plane direction of the sapphire substrate when viewed from the nitride semiconductor plane side.

Further, according to the method of manufacturing a laser device of the present invention, after growing a nitride semiconductor having an active layer that oscillates laser on the A-plane of the sapphire substrate, the substrate is cleaved along the R-plane, and the cleavage is performed. At the same time, a resonance surface of the laser beam is formed on a cleavage plane of the active layer which is obtained at a plane different from the R-plane of the substrate.

[0009]

FIG. 1 is a unit cell diagram showing the plane orientation of a sapphire single crystal. Sapphire has a rhombohedral structure to be precise, but can be approximated by a hexagonal system as shown in this figure. In the method of the present invention, the nitride semiconductor is grown on the A-plane of sapphire as shown by the hatched portion in the figure. The A-plane is expressed in plane orientation, for example,

(Equation 1) In the present invention, the nitride semiconductor grown on the A-plane is cleaved at the R-plane. As shown in FIG.
If the plane is shown in plane orientation, for example,

(Equation 2) It can be shown. When sapphire is used as a crystal growth surface with the A-plane as a crystal growth plane and cleaved in the R-plane orientation, the substrate can be cleaved to a desired size, and a sapphire cleavage plane close to a mirror surface can be obtained. Before cleaving the substrate further, reduce the thickness of the substrate to 15
Polishing to a thickness of 0 μm or less, and more preferably 100 μm or less, makes the cleavage easier.

Hereinafter, the operation of the laser device of the present invention will be described mainly with reference to a manufacturing method. In the laser device of the present invention, the nitride semiconductor layer having the active layer that performs laser oscillation is grown on the A-plane of sapphire. By growing the nitride semiconductor on the A-plane, the nitride semiconductor can be oriented and grown so as to be easily cleaved. Next, the substrate on which the nitride semiconductor has been crystal-grown on the A-plane is cleaved on the R-plane. The sapphire substrate cleaved on the R-plane has the property of being split straight into a mirror surface due to its cleavage. On the other hand, a nitride semiconductor grown on sapphire has the same hexagonal system as sapphire, but is not cleaved on the R plane because of a different lattice constant. However,
When the nitride semiconductor grown on the A plane is cleaved on the R plane, it tends to be cleaved on a certain plane at the same time as the sapphire is cleaved due to the orientation of the nitride semiconductor crystal. By making the cleavage plane of the nitride semiconductor layer cleaved at the certain plane coincide with the end face of the active layer, a resonance surface close to a mirror surface obtained by cleavage at the end face of the active layer can be produced.
This is the operation of the present invention.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 is a plan view of a nitride semiconductor wafer for explaining one step of the manufacturing method of the present invention, and the figure shows the wafer as viewed from the semiconductor layer side. FIG. 3 is a schematic perspective view showing the shape of a laser element cut out from the wafer of FIG. 2, and these figures show an electrode stripe type laser element for easy understanding of the present invention. I have.

The nitride semiconductor layer grown on the A-plane of sapphire is basically composed of an n-type layer for confining light, an active layer for laser oscillation on the n-type layer, and It has a structure in which p-type layers that confine light are stacked.
In the electrode stripe type laser device, as shown in the figure,
A part of the p-type layer, the active layer, and the n-type layer is etched in a direction parallel to a laser resonance direction (II direction in FIG. 2), so that the nitride semiconductor layer including the active layer has a stripe shape. Have.

Next, the wafer grown on the A-plane is cleaved at the R-plane. The R plane corresponds to the II-II direction shown in the figure,
When cleaved at the plane, the p-layer nitride semiconductor layer does not break straight along the R-plane, and countless irregularities or jaggies occur on the cleavage plane as shown in FIG. If the cleavage plane has a stripe width of 20 μm or less, as shown in this figure, the cleavage planes are easily cleaved obliquely in a shape different from the shape of the cleavage plane of the n-layer. Moreover, since the cleavage planes are parallel to each other, if there is an active layer in the stripe, the cleavage plane becomes a resonance plane of the active layer. The stripe width which has a certain degree of regularity and is easily broken is 20 μm or less, and more preferably 10 μm or less. That is, if the width of the resonance surface of the active layer is 20 μm or less, preferable parallel resonance surfaces are easily obtained. FIG. 3 shows the shape of the laser element. As shown in this figure, the cleavage plane (R plane) of sapphire is different from the cleavage plane of the nitride semiconductor having the active layer, and the resonance plane of the laser is shown. The resonance surface of the active layer is not in the same horizontal plane as the R surface, and has a twisted relationship.

FIG. 4 is a plan view of a nitride semiconductor wafer for explaining one step of the manufacturing method of the present invention, similarly to FIG.
The figure which looked at the wafer from the semiconductor layer side is shown. Also,
FIG. 5 is an enlarged view showing a part of the wafer of FIG.
FIG. 6 is a schematic perspective view showing the shape of the laser element cut out from FIG. 3 and 6, the cross-sectional shape of the chip cut in the direction of II is
Since it is not particularly related to the present invention, it is shown by a straight line.

FIGS. 4 to 6 show a state in which a nitride semiconductor layer having an active layer is not etched in a stripe shape and a laser device of, for example, a refractive index waveguide type is manufactured. The present invention can be applied to such a laser device. The hatched portion shown in FIG. 4 indicates a waveguide region of the active layer, and this region can be manufactured by, for example, forming a current confinement layer, a current blocking layer, and the like in the nitride semiconductor layer. The active layer oscillates in this region. As shown in FIG. 4, when the nitride semiconductor having an active region on the A-plane of the sapphire substrate is cleaved along the R-plane (II-II), as in FIG. Jagging occurs, and the jagged inclined surfaces tend to be parallel to each other. A preferred length parallel to each other is 20 μm or less in a direction parallel to the R plane,
If the width of the active layer is set within the range, the cleavage plane can be a resonance plane.

According to our experiments, the angle at which the nitride semiconductor is cleaved is, as shown in FIG. 5, often cracked within a range of ± θ2 from the direction of right and left θ1 with respect to the cleavage plane and R plane of the substrate. . In other words, nitride semiconductors are often cleaved from the R plane in a range of ± θ2 with right and left θ1 as the center,
In the laser device of the present invention, θ1 is equivalent to 5 ° and θ2 is ± 4.
Equivalent to ゜. Within this range, cleavage planes parallel to each other and close to a mirror surface are easily obtained.

Moreover, the shape has a certain degree of regularity, and the planes cleaved by II-II and II-II tend to be parallel to each other. Therefore, since the cleavage planes are parallel to each other, if there is a stripe active layer on this parallel plane, the end face of the active layer becomes a resonance plane. FIG. 6 shows a perspective view of the laser element. The nitride semiconductor is etched so that the n-layer is exposed in order to extract the negative electrode. The negative electrode is not specifically shown.

When the wafer having the nitride semiconductor grown on the A-plane of the sapphire substrate is cleaved along the R-plane of the substrate as described above, the nitride semiconductor having the active layer cleaved simultaneously with the substrate is formed by the R Cleaved in a direction different from the plane. In addition, since the cleavage planes of the nitride semiconductor are parallel to each other, it can be a laser resonance plane. Needless to say, a reflecting mirror such as a dielectric multilayer film or a metal thin film may be formed on the cleavage surface in a usual manner in order to produce a complete resonance surface.

[Embodiment 1] FIG. 7 is a schematic sectional view showing the structure of a laser device according to an embodiment of the present invention, and shows a view when the device is cut along the R-plane of sapphire. The first embodiment will be described below with reference to FIG.

After a sapphire substrate 10 having a thickness of 500 μm having a crystal growth surface A as a plane is placed in a reaction vessel of a MOVPE apparatus, TMG (trimethylgallium) is used as a source gas.
And ammonia on the surface of the substrate at a temperature of 500 ° C.
A buffer layer of aN was grown to a thickness of 200 Å. This buffer layer has the effect of alleviating the lattice mismatch between the substrate and the nitride semiconductor.
Although it is possible to grow lGaN or the like, this buffer layer is not particularly shown.

Subsequently, the temperature was raised to 1050 ° C.
With TMG, ammonia and SiH as donor impurities
_FourMade of Si-doped GaN using (silane) gas
The n-type contact layer 11 was grown to a thickness of 4 μm. n
Type contact layer is In_XAl_YGa _1-XYN (0 ≦ X, 0 ≦
Y, X + Y ≦ 1), especially GaN, I
nGaN, of which GaN doped with Si
As a result, an n-type layer having a high carrier concentration can be obtained,
A good ohmic contact with the negative electrode
The threshold current of the laser element can be reduced.

Next, while maintaining the temperature at 1050 ° C., a current blocking layer 20 made of Mg-doped p-type GaN was grown to a thickness of 0.5 μm using TMG and ammonia as source gases and Cp 2 Mg as an impurity gas. . This current blocking layer has the effect of later focusing the current on the active layer to produce a waveguide.

After growing the current blocking layer 20, the wafer was taken out of the reaction vessel, and the current blocking layer 20 was mesa-etched in a V-groove shape to a depth reaching the n-type contact layer 11, as shown in FIG. The width of the V-groove is 5 μm, and the current blocking layer 20
Was formed in a stripe shape at a depth of 2.5 μm on the surface of the substrate.

Next, the wafer is transferred to the reaction vessel again, the temperature is set to 750 ° C., and TMG, TMI (trimethylindium), ammonia is used as a source gas, silane gas is used as an impurity gas, and Si-doped In 0.1 Ga 0.9 N is used. An anti-crack layer was grown to a thickness of 500 Å. Although this crack prevention layer is not particularly shown, In
By growing an n-type nitride semiconductor containing Al, preferably InGaN, it becomes possible to grow an n-type optical confinement layer 12 made of a nitride semiconductor containing Al to be grown next as a thick film. In the case of LD, it is necessary to grow a layer to be a light confinement layer and a light guide layer with a thickness of, for example, 0.1 μm or more. Conventionally, when thick AlGaN was directly grown on the GaN and AlGaN layers, cracks were formed in the AlGaN grown later, making it difficult to fabricate the device. Cracks in the layer can be prevented.
In addition, even if the optical confinement layer 3 to be grown next is grown as a thick film, it can be grown with good film quality. In addition, this crack prevention layer is 1
It is preferable to grow the film to a thickness of not less than 00 Å and not more than 0.5 μm. When the thickness is less than 100 Å, it is difficult to function as a crack prevention as described above, and when the thickness is more than 0.5 μm, the crystal itself tends to turn black. The crack prevention layer may be omitted depending on the growth method and the growth apparatus.

Next, an n-type optical confinement layer 12 made of Si-doped n-type Al0.3 Ga0.7 N is formed to a thickness of 0.5 μm using TEG, TMA (trimethylaluminum) and ammonia as source gases and silane gas as an impurity gas. Grown in thickness. The n-type optical confinement layer 12 is made of an n-type nitride semiconductor containing Al, and preferably has a binary mixed crystal or ternary mixed crystal of Al _Y Ga _1-Y N (0 <Y ≦ 1). It is effective in confining the longitudinal mode of laser light by increasing the difference in refractive index from the active layer. This layer is usually preferably grown to a thickness of 0.1 μm to 1 μm. If the thickness is less than 0.1 μm, it does not easily function as a light confinement layer.

Subsequently, TMG, ammonia,
Si-doped n-type GaN using silane gas as impurity gas
An n-type light guide layer 13 was grown to a thickness of 500 angstroms. The n-type optical guide layer 13 is made of an n-type nitride semiconductor containing In or n-type GaN, and preferably a ternary mixed crystal or a binary mixed crystal of In _x Ga ₁ -xN.
(0 ≦ X <1). This layer is usually preferably grown to a thickness of 100 angstroms to 1 μm. In particular, by using InGaN or GaN, the next active layer can easily have a quantum well structure.

Next, the active layer 14 was grown using TMG, TMI, and ammonia as source gases. The active layer has a temperature of 7
While maintaining the temperature at 50 ° C., first, a well layer made of non-doped In0.2Ga0.8N is grown to a thickness of 25 Å. Next, a barrier layer made of non-doped In0.01Ga0.95N was deposited at the same temperature by changing only the molar ratio of TMI.
It is grown to a thickness of 0 Å. This operation is 1
Repeat three times and finally grow the well layer to a total thickness of 0.1μ
An active layer 14 having a multiple quantum well structure having a thickness of m was grown.

After the active layer 14 is grown, the temperature is raised to 1050 ° C., and TMG, TMA, ammonia, Cp 2 Mg (cyclopentadienyl magnesium) is used as an acceptor impurity source, and the p-type cap is made of Mg-doped p-type Al 0.2 Ga 0.8 N. The layer was grown to a thickness of 100 Å. Although this p-type cap layer is not particularly shown,
By growing at a film thickness of 1 μm or less, more preferably 10 Å or more and 0.1 μm or less,
The active layer made of nGaN acts as a cap layer for preventing decomposition, and the growth of a p-type cap layer made of a p-type nitride semiconductor containing Al on the active layer significantly increases light emission output. To improve. Conversely, if the p-layer in contact with the active layer is GaN, the output of the device will be reduced to about 1/3. This is because AlGaN is more likely to be p-type than GaN, and when growing a p-type cap layer, InGa
It is presumed that this has the effect of suppressing the decomposition of N, but the details are unknown. If the thickness of the p-type cap layer is larger than 1 μm, cracks tend to be formed in the layer itself, which tends to make element fabrication difficult. Note that this p-type cap layer can also be omitted.

Next, while maintaining the temperature at 1050 ° C., T
Mg-doped p-type G using MG, ammonia, Cp2Mg
A p-type optical guide layer 15 made of aN was grown to a thickness of 500 Å. This p-type light guide layer 15
It is composed of a nitride semiconductor containing In or GaN, preferably a binary mixed crystal or a ternary mixed crystal of In _Y Ga _{1 -Y} N (0 <
Grow Y ≦ 1). It is desirable that the light guide layer is usually grown to a thickness of 100 Å to 1 μm.
The optical confinement layer can be grown with good crystallinity.

Subsequently, TMG, TMA, ammonia, C
Using p2Mg, a p-type optical confinement layer 16 made of Mg-doped Al0.3Ga0.7N was grown to a thickness of 0.5 .mu.m. The p-type optical confinement layer 16 is made of a p-type nitride semiconductor containing Al, and preferably has a binary or ternary mixed crystal Al _Y Ga ₁ -YN (0 <Y ≦ 1). Thereby, a material having good crystallinity can be obtained. Like the n-type optical confinement layer, the p-type optical confinement layer is preferably grown to a thickness of 0.1 μm to 1 μm. By forming the p-type nitride semiconductor containing Al such as AlGaN, It functions effectively as a light confinement layer by increasing the refractive index difference.

Subsequently, TMG, ammonia, Cp2Mg
The p-type contact layer 17 made of Mg-doped p-type GaN was grown to a thickness of 0.5 μm. The p-type contact layer 17 is made of p-type In _x Al _Y Ga _{1 -XYN} (0 ≦ X, 0 ≦
Y, X + Y ≦ 1), especially InGa
When p-type GaN doped with N and GaN, particularly Mg, is used, a p-type layer having the highest carrier concentration can be obtained, good ohmic contact with the positive electrode can be obtained, and the threshold current can be reduced. . Note above-described n-type layer of the general formula Al _X Ga _1-X N, the composition ratio X values such as Al _X Ga _1-X N of the p-type layer is merely shows the general formula, n-type layer X and the X of the p-type layer do not show the same value. Similarly, the Y values used in other general formulas do not indicate the same value in the same general formula.

The wafer on which the nitride semiconductor has been laminated as described above is taken out of the reaction vessel, and the uppermost p-type contact layer is selectively etched by a reactive ion etching (RIE) apparatus to form a negative electrode. The plane of the n-type contact layer 11 to be exposed was exposed. Next, a positive electrode is formed on almost the entire surface of the uppermost p-type contact layer 17, and the exposed n
A striped negative electrode was formed on the mold contact layer.

After the electrodes are formed, the wafer is transferred to a polishing apparatus, and the sapphire substrate is polished to a thickness of 80 μm to reduce the thickness. Then, a scratch is formed on the nitride semiconductor layer side corresponding to the R surface of the sapphire substrate surface. Cleave the substrate by external force,
A semiconductor bar having a cleavage plane exposed was manufactured. As a result of this operation, the sapphire substrate was cleaved at the R-plane, but the cleavage surface of the nitride semiconductor layer was cleaved at a different twist position from the R-plane of the substrate. However, in the cleavage plane of the nitride semiconductor layer, the cleavage plane of the V-groove including the n-type optical confinement layer, the active layer, and the p-type optical confinement layer is a mirror plane, and the cleavage plane is parallel to the cleavage plane. Was.

After a reflecting mirror made of a dielectric multilayer film is formed on the cleavage plane of the semiconductor bar obtained as described above using a sputtering apparatus, the bar is cut by dicing at a position perpendicular to the R plane. To make a 500 μm square laser chip. Place this laser chip on the heat sink,
When pulse oscillation is performed at room temperature, the threshold current density is 2k
A laser emission of 410 nm at A / cm ² was exhibited.

Example 2 In Example 1, the nitride semiconductor from the buffer layer to the p-type contact layer 17 was grown on the A surface of the sapphire substrate without growing the current blocking layer 20.

Next, this wafer was replaced with p in the same manner as in Example 1.
The surface of the n-type contact layer 11 on which an electrode is to be formed is exposed by etching from the side of the type contact layer 17 in a direction perpendicular to the R plane. As shown in FIG. 2 and FIG. The stripe width of the semiconductor layer is 10μ
m to form an electrode stripe type. Thereafter, a positive electrode and a negative electrode were formed in a direction parallel to the stripe.

After the formation of the electrodes, the wafer was cleaved in a direction perpendicular to the stripes, that is, along the R plane of the substrate in the same manner as in Example 1, to produce semiconductor bars. As a result of the cleavage, the substrate was cleaved on the R-plane, but the nitride semiconductor layer having the active layer and having a stripe width of 10 μm was cleaved on a plane shifted from the R-plane by about 3 °, and the cleavage plane of the nitride semiconductor was cleaved. A resonance surface close to a mirror surface where the and the cleavage plane are parallel to each other was produced.

Thereafter, a reflecting mirror made of a dielectric multilayer film is formed on the cleavage plane of the bar by using a plasma CVD apparatus.
The chip was cut by dicing at a position parallel to the electrodes to form a laser chip. This laser chip was placed on a heat sink and pulsed at room temperature. As a result, a laser oscillation of 410 nm was shown at a threshold current density of 2.5 kA / cm ² .

Example 3 Example 2 except that the width of the stripe etched from the p-type contact layer was set to 20 μm.
When a bar was produced in the same manner as in the above, the cleavage plane of the striped nitride semiconductor layer having the active layer was cleaved in a direction shifted from the R plane by about 8 °. When the bar was similarly formed into a laser chip, the laser oscillated at a threshold current density of 3 kA / cm ² .

[0040]

As described above, according to the present invention, a laser device made of a nitride semiconductor whose resonance surface is formed by cleavage can be manufactured. On the other hand, when a resonance surface is formed by means such as etching or polishing, the resonance surface is likely to have irregularities, so that the threshold current is increased. It can also be done. The fact that the resonance surface was made of a nitride semiconductor in this way is very significant for practical use of a nitride semiconductor laser device.

[Brief description of the drawings]

FIG. 1 is a unit cell diagram showing the plane orientation of a sapphire single crystal.

FIG. 2 is a plan view of a nitride semiconductor wafer for explaining one step of the method of the present invention.

FIG. 3 is a schematic perspective view showing the shape of a laser device cut out from the wafer of FIG. 2;

FIG. 4 is a plan view of a nitride semiconductor wafer for explaining one step of the method of the present invention.

FIG. 5 is an enlarged plan view showing a part of the wafer of FIG. 4;

FIG. 6 is a schematic perspective view showing the shape of a laser device cut out from the wafer of FIG. 4;

FIG. 7 is a schematic sectional view showing the structure of a laser device according to one embodiment of the present invention.

[Explanation of symbols]

 10 sapphire substrate 11 n-type contact layer 20 p-type current blocking layer 12 n-type light confinement layer 13 n-type light guide layer 14 · Active layer 15 ··· p-type light guide layer 16 ··· p-type light confinement layer 17 ··· p-type contact layer

Continuation of Front Page (56) References JP-A-64-64811 (JP, A) JP-A-5-343742 (JP, A) Journal of The American Ceramic Society Vol. 52, No. 9, p.p. 485-491 (1969) Journal of Crystal Growth Vol. 40, No. 2, pp. 239-252 (1977) Japanese Journal of Applied Physics Part2 Vol. 35, No. 2B, pp. L217-L220 (58) Field surveyed (Int. Cl. ⁷ , DB name) H01S 5/00-5/50 H01L 33/00

Claims (5)

(57) [Claims] 1. A nitride semiconductor having an active layer for laser oscillation is grown on an A-plane of a sapphire substrate, and the sapphire substrate is cleaved on an R-plane and an active semiconductor not on the same horizontal plane as the R-plane. A nitride semiconductor laser device, wherein a cleavage plane of a layer is a resonance plane. 2. The method according to claim 1, wherein the width of the waveguide region of the active layer is 20 μm.
The nitride semiconductor laser device is limited to the following, wherein the nitride semiconductor surface on which the substrate is cleaved is jagged, and the jagged parallel inclined surfaces are resonance surfaces. 3. The nitride semiconductor laser device according to claim 1, wherein said substrate has a thickness of 150 μm or less. 4. The device according to claim 1, wherein the resonance surface is within a range of 5 ° ± 4 ° left and right with respect to the R-plane direction of the sapphire substrate when viewed from the nitride semiconductor plane side.
4. The laser device according to item 1. 5. After growing a nitride semiconductor having an active layer that oscillates laser on the A-plane of the sapphire substrate, the substrate is cleaved along the R-plane, and is obtained at the same time as the cleaving. A method for manufacturing a nitride semiconductor laser device, comprising forming a laser light resonance surface on a cleavage plane of an active layer cleaved on a different plane.