JP5428605B2 - Manufacturing method of semiconductor laser device - Google Patents

Description

  The present invention relates to a method of manufacturing a semiconductor laser device in which a dielectric reflection film is coated on a laser transmission surface and a reflection surface, and more particularly to a method of manufacturing a semiconductor laser element capable of preventing an unnecessary dielectric reflection film from adhering.

  When manufacturing a laser diode (LD) of a semiconductor laser device, a low-reflectivity dielectric reflection film and a high-reflectivity dielectric reflection film are formed on a laser transmission surface and a reflection surface, respectively. As a result, it is possible to prevent the laser transmission surface and the reflection surface from being destroyed or deteriorated, and to improve the characteristics and reliability of the laser diode.

  When forming the dielectric reflection film, it is inefficient to form the dielectric reflection film separately for each laser diode. For this reason, the following manufacturing method of the first semiconductor laser device has been applied (for example, Patent Document 1). 12 to 16 are process diagrams showing a first method of manufacturing a semiconductor laser device according to the prior art. Note that FIG. 16 is an enlarged view in the broken line frame of FIG.

  First, as shown in FIG. 12, a semiconductor layer 104 including an active layer 102 where stimulated emission of laser is performed is formed on the surface 100 a side of the semiconductor substrate 100.

  Next, as illustrated in FIG. 13, an electrode layer 106 including an insulating film and a plating layer is formed on the entire surface 104 a of the semiconductor layer 104. Similarly, the electrode layer 106 is formed on the entire back surface 100 b of the semiconductor substrate 100.

  Next, the semiconductor substrate 100 is cleaved along the direction of arrow a. As a result, as shown in FIG. 14, a semiconductor laser bar 110 including a plurality of laser diodes 108 is formed. One of the cleavage surfaces 110c of the semiconductor laser bar 110 is a transmission surface, and the other is a reflection surface. A surface intersecting the surface 110a and the cleavage surface 110c is a side wall surface 110d. The distance between the transmission surface and the reflection surface indicated by the broken line arrow is the resonator length. The electrode layer 106 straddles a plurality of laser diodes 108.

  Next, as shown in FIG. 15, a plurality of semiconductor laser bars 110 and a plurality of spacer bars 112 are alternately stacked. At this time, the front surface 110a and the back surface 110b of the semiconductor laser bars 110 adjacent to each other are made to face each other. And those cleavage surfaces 110c are made to face the same direction. In addition, the length of the spacer bar 112 in the resonator length direction is made shorter than the resonator length indicated by the broken line arrow of the semiconductor laser bar 110. As a result, the cleaved surface 110 c of the semiconductor laser bar 110 is projected from the spacer bar 112. Then, the material of the dielectric reflection film is advanced in the direction of the arrow c perpendicular to the cleavage plane 110c of the semiconductor laser bar 110. Thus, as shown in FIG. 16, the dielectric reflection film 114 is coated on the cleavage surface 110 c of the semiconductor laser bar 110.

  In this method, the cleavage surface 110 c of the semiconductor laser bar 110 is protruded with respect to the spacer bar 112. For this reason, the cleaved surface 110 c does not become a shadow of the spacer bar 112 when coating the dielectric reflecting film 114. Therefore, it is possible to prevent the thickness of the dielectric reflecting film 114 coated near the active layer 102 of the cleavage plane 110c from varying.

  However, in this method, as shown in FIG. 13, the electrode layer 106 is formed on the entire surface of the front surface 104 a of the semiconductor layer 104 and the back surface 100 b of the semiconductor substrate 100. For this reason, it is difficult to cleave the semiconductor substrate 100 to form the semiconductor laser bar 110. It is also difficult to separate the individual laser diodes 108 from the semiconductor laser bar 110. Therefore, there has been a demand for easy cleavage of the semiconductor substrate 100 and separation of the laser diode 108.

JP-A-10-93187

  In order to meet this demand, the following second method of manufacturing a semiconductor laser device has been applied. 17 to 20 are process diagrams showing the main part of the second method for manufacturing a semiconductor laser device according to the prior art. FIG. 20 is an enlarged view inside the broken line frame of FIG.

  First, the semiconductor layer 104 is formed on the surface 100a side of the semiconductor substrate 100 as in the first method for manufacturing a semiconductor laser device. Next, as shown in FIG. 17, a plurality of surface-side electrodes 116 are formed on the surface 104a of the semiconductor layer 104 so as to be separated from each other so as to be aligned in the direction of arrow a and the direction of arrow b intersecting this direction. . Similarly, a plurality of backside electrodes 118 are formed on the backside 100b of the semiconductor substrate 100 so as to be separated from each other so as to be arranged at positions facing the frontside electrodes 116.

  Next, the semiconductor substrate 100 is cleaved along the direction of the arrow a at a position away from the front surface side electrode 116 and the back surface side electrode 118. As a result, as shown in FIG. 18, a semiconductor laser bar 122 including a plurality of laser diodes 120 is formed. One of the cleavage surfaces 122c of the semiconductor laser bar 122 is a transmission surface, and the other is a reflection surface. A surface intersecting the surface 122a and the cleavage surface 122c is a side wall surface 122d. The distance between the transmission surface and the reflection surface indicated by the broken line arrow is the resonator length.

  At this time, on the surface 104a of the semiconductor layer 104 of the semiconductor laser bar 122, a first gap 124 is formed between the cleavage surface 122c and the end portion 116a of the surface side electrode 116 on the cleavage surface side. Similarly, on the back surface 100b of the semiconductor substrate 100 of the semiconductor laser bar 122, a second gap 126 is formed between the cleavage surface 122c and the end portion 118a of the back surface side electrode 118 on the cleavage surface side.

  Next, as shown in FIG. 19, a plurality of semiconductor laser bars 122 and a plurality of spacer bars 112 are alternately stacked in the same manner as in the first method of manufacturing a semiconductor laser device, and their cleavage surfaces 122c are formed on the spacer bars 112. Protruding against. Then, the material of the dielectric reflection film is advanced in the direction of the arrow c perpendicular to the cleavage surface 122c of the semiconductor laser bar 122. Thereby, as shown in FIG. 20, the dielectric reflection film 114 is coated on the cleavage surface 122 c of the semiconductor laser bar 122.

  In the manufacturing method according to this problem, when coating the dielectric reflection film 114, the first gap 124, the edge 116 a on the cleaved surface side of the front surface side electrode 116, the second gap 126, and the cleaved surface of the back surface side electrode 118. The material of the dielectric reflection film 114 goes to the vicinity of the side end portion 118a. As a result, the unnecessary dielectric reflection film 114 adheres to the first gap 124, the cleaved surface side end portion 116a, the second gap 126, and the cleaved surface side end portion 118a.

  The unnecessary dielectric reflection film 114 is peeled off and reattached in the process after coating the dielectric reflection film 114, and this causes a defect in the appearance of the semiconductor laser bar 122. Further, the presence of the unnecessary dielectric reflection film 114 may prevent the semiconductor laser bar 122 and the cooling package from being joined. In this case, when the laser is oscillated, the laser diode 120 is not sufficiently cooled, resulting in poor characteristics of the laser diode 120.

  Further, since the surface side electrode 116 protrudes with respect to the spacer bar 112, a third gap 128 is formed between the cleaved surface side end portion 118 a and the spacer bar 112 in the surface side electrode 116. Similarly, since the back surface side electrode 118 protrudes with respect to the spacer bar 112, a fourth gap 130 is formed between the cleaved surface side end portion 118 a and the spacer bar 112 in the back surface side electrode 118. Therefore, the unnecessary dielectric reflection film 114 is also attached to the third gap 128 and the fourth gap 130. This can cause the above problems as well.

  The present invention has been made to solve this problem, and an object of the present invention is to provide a method of manufacturing a semiconductor laser device that can prevent an unnecessary dielectric reflection film from adhering.

According to a first aspect of the present invention, there is provided a method for manufacturing a semiconductor laser device, comprising: forming a semiconductor layer including an active layer on a surface side of a semiconductor substrate; Forming a plurality of backside electrodes so as to be arranged in a second direction intersecting the first direction, and separating the plurality of backside electrodes from each other so as to be arranged at positions facing the front side electrodes on the backside of the semiconductor substrate. Forming a semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode; and a first rectangular parallelepiped . And the second spacer bar sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate, respectively, on the cleavage surface of the semiconductor laser bar A step of coating an electroreflecting film, and when forming the semiconductor laser bar, a surface of the semiconductor layer of the semiconductor laser bar is formed between the cleaved surface and an end of the surface-side electrode on the cleaved surface side. A first gap is formed, and a second gap is formed between the cleaved surface and an end of the backside electrode on the cleaved surface side on the back surface of the semiconductor substrate of the semiconductor laser bar. When coating the dielectric reflecting film, the end portions of the first and second spacer bars are perpendicular to the cleaved surfaces from the cleaved surface side ends of the front surface side electrode and the back surface side electrode. in the direction of a position away from said cleavage plane in a direction, and to come respectively, when coating the dielectric reflective film, it perpendicular to the cleavage plane of the semiconductor laser bar The, in the direction inclined to the direction of the surface side of the semiconductor layer of the semiconductor laser bar from the center of the cleavage plane, is characterized in that the advancing material of the dielectric reflective film.

According to a second aspect of the present invention, there is provided a method for manufacturing a semiconductor laser device, comprising: forming a semiconductor layer including an active layer on a surface side of a semiconductor substrate; and a plurality of surface side electrodes on the surface of the semiconductor layer in a first direction and Forming a plurality of backside electrodes so as to be arranged in a second direction intersecting the first direction, and separating the plurality of backside electrodes from each other so as to be arranged at positions facing the front side electrodes on the backside of the semiconductor substrate. Forming a semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode; and a first rectangular parallelepiped . And the second spacer bar sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate, respectively, on the cleavage surface of the semiconductor laser bar A step of coating an electroreflecting film, and when forming the semiconductor laser bar, a surface of the semiconductor layer of the semiconductor laser bar is formed between the cleaved surface and an end of the surface-side electrode on the cleaved surface side. When the dielectric reflective film is coated so that a first gap is formed between the first and second spacer bars, the surface-side electrode has a cleaved surface-side end and the first spacer bar. When the dielectric reflection film is coated so that a second gap is formed between them, the direction perpendicular to the cleavage surface of the semiconductor laser bar is set to the surface side of the semiconductor layer of the semiconductor laser bar from the center of the cleavage surface. The material of the dielectric reflecting film is advanced in a direction inclined in the direction of.

According to a third aspect of the present invention, there is provided a method for manufacturing a semiconductor laser device, comprising: forming a semiconductor layer including an active layer on a surface side of a semiconductor substrate; and a plurality of surface side electrodes on the surface of the semiconductor layer in a first direction and Forming a plurality of backside electrodes so as to be arranged in a second direction intersecting the first direction, and separating the plurality of backside electrodes from each other so as to be arranged at positions facing the front side electrodes on the backside of the semiconductor substrate. Forming a semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode; and a first rectangular parallelepiped . And the second spacer bar sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate, respectively, on the cleavage surface of the semiconductor laser bar A step of coating an electric reflecting film, and when forming the semiconductor laser bar, on the back surface of the semiconductor substrate of the semiconductor laser bar, the cleavage surface and an end of the back surface side electrode on the cleavage surface side When the dielectric reflective film is coated such that a first gap is formed between the end surface of the rear surface side electrode and the second spacer bar between the end of the rear surface side electrode on the cleavage surface side and the second spacer bar. When the dielectric reflection film is coated so that a second gap is formed between them, the direction perpendicular to the cleavage plane of the semiconductor laser bar is set to the back side of the semiconductor substrate of the semiconductor laser bar from the center of the cleavage plane. The material of the dielectric reflecting film is advanced in a direction inclined in the direction of.

  According to the present invention, it is possible to prevent an unnecessary dielectric reflection film from adhering.

6 is a process diagram illustrating the method of manufacturing the semiconductor laser device according to the first embodiment. FIG. 6 is a process diagram illustrating the method of manufacturing the semiconductor laser device according to the first embodiment. FIG. 6 is a process diagram illustrating the method of manufacturing the semiconductor laser device according to the first embodiment. FIG. 6 is a process diagram illustrating the method of manufacturing the semiconductor laser device according to the first embodiment. FIG. 6 is a process diagram illustrating the method of manufacturing the semiconductor laser device according to the first embodiment. FIG. FIG. 10 is a process diagram illustrating a main part of a method of manufacturing a semiconductor laser device according to a modification of the first embodiment. FIG. 10 is a process diagram illustrating a main part of a method for manufacturing the semiconductor laser device according to the second embodiment. FIG. 11 is a process diagram showing a main part of a method for manufacturing a semiconductor laser device according to a third embodiment. FIG. 10 is a process diagram illustrating a main part of a method for manufacturing a semiconductor laser device according to a modification of the third embodiment. FIG. 10 is a process diagram showing a main part of a method for manufacturing a semiconductor laser device according to a fourth embodiment. FIG. 10 is a process diagram illustrating a main part of a method for manufacturing a semiconductor laser device according to a modification of the fourth embodiment. It is process drawing which shows the manufacturing method of the 1st semiconductor laser apparatus based on a prior art. It is process drawing which shows the manufacturing method of the 1st semiconductor laser apparatus based on a prior art. It is process drawing which shows the manufacturing method of the 1st semiconductor laser apparatus based on a prior art. It is process drawing which shows the manufacturing method of the 1st semiconductor laser apparatus based on a prior art. It is process drawing which shows the manufacturing method of the 1st semiconductor laser apparatus based on a prior art. It is process drawing which shows the principal part of the manufacturing method of the 2nd semiconductor laser apparatus based on a prior art. It is process drawing which shows the principal part of the manufacturing method of the 2nd semiconductor laser apparatus based on a prior art. It is process drawing which shows the principal part of the manufacturing method of the 2nd semiconductor laser apparatus based on a prior art. It is process drawing which shows the principal part of the manufacturing method of the 2nd semiconductor laser apparatus based on a prior art.

Embodiment 1 FIG.
The first embodiment relates to a method for manufacturing a semiconductor laser device. In particular, the semiconductor laser device according to the first embodiment includes an information processing device such as an optical disk writing device, an Nd-doped YAG (Nd: YAG) laser, a Yb-doped YAG (Yb: YAG) laser, a Yb-doped fiber laser, and an Er. It is used as a device for an excitation light source such as a doped fiber amplifier laser and a device for optical communication. The same applies to semiconductor laser devices according to the following embodiments. Hereinafter, the manufacturing method according to Embodiment 1 will be described. 1 to 5 are process diagrams showing the method of manufacturing the semiconductor laser device according to the first embodiment. FIG. 5 is an enlarged view in the broken line frame of FIG.

  First, as shown in FIG. 1, a semiconductor layer 14 including an active layer 12 where stimulated emission of laser is performed is formed on the surface 10 a side of the semiconductor substrate 10. At this time, the active layer 12 and the semiconductor layer 14 are formed using a vapor phase epitaxial method or a liquid phase epitaxial method. Further, GaAs, InP, GaN or the like is used for the semiconductor substrate 10, and InGaAs, InGaAsP, InGaP, AlGaInP, InGaN, AlGaN or the like is used for the active layer 12 and the semiconductor layer 14. For the active layer 12 and the semiconductor layer 14, Si, Mg, Zn, or the like is used as an additive impurity.

  Next, as shown in FIG. 2, the plurality of surface side electrodes 16 are arranged on the surface 14a of the semiconductor layer 14 in the direction of the arrow a (first direction) and the direction of the arrow b (first direction) intersecting the direction of the arrow a. 2) and spaced apart from each other. Similarly, a plurality of back surface side electrodes 18 are formed apart from each other so as to be arranged in a position facing the front surface side electrode 16 on the back surface 10 b of the semiconductor substrate 10. At this time, a lift-off method, a vacuum deposition method, a sputtering method, or the like is used.

  Next, the semiconductor substrate 10 is cleaved along the direction of the arrow a at a position away from the front surface side electrode 16 and the back surface side electrode 18. Thereby, as shown in FIG. 3, a semiconductor laser bar 22 including a plurality of laser diodes 20 is formed. One of the cleavage surfaces 22c of the semiconductor laser bar 22 is a transmission surface, and the other is a reflection surface. A surface intersecting with the surface 22a and the cleavage surface 22c is a side wall surface 22d. The distance between the transmission surface and the reflection surface indicated by the broken line arrow is the resonator length.

  At this time, on the surface 14a of the semiconductor layer 14 of the semiconductor laser bar 22, a first gap 24 is formed between the cleaved surface 22c and the end 16a of the front surface side electrode 16 on the cleaved surface side. Similarly, on the back surface 10b of the semiconductor substrate 10 of the semiconductor laser bar 22, a second gap 26 is formed between the cleavage surface 22c and the end portion 18a of the back surface side electrode 18 on the cleavage surface side.

  Next, as shown in FIG. 4, the semiconductor laser bars 22 and the spacer bars 28 are alternately stacked. At this time, the front surface 22a and the back surface 22b of the semiconductor laser bars 22 adjacent to each other are made to face each other. And those cleavage surfaces 22c are made to face the same direction. Further, the upper spacer bar (first spacer bar) 28 and the lower spacer bar (second spacer bar) 28 of the semiconductor laser bar 22 are protruded from the cleaved surface 22 c of the semiconductor laser bar 22.

  Next, with the upper spacer bar 28 and the lower spacer bar 28 sandwiching the semiconductor laser bar 22 from the surface 14a side of the semiconductor layer 14 and the back surface 10b side of the semiconductor substrate 10, respectively, the direction perpendicular to the cleavage plane 22c is The material of the dielectric reflection film 30 is advanced in the direction of the arrow e inclined from the center of the cleavage plane 22c toward the surface 14a of the semiconductor layer 14. As a result, as shown in FIG. 5, the dielectric reflection film 30 is coated on the cleavage plane 22c.

  In this method, when the semiconductor laser bar 22 and the spacer bar 28 are stacked, the width for projecting the spacer bar 28 below the semiconductor laser bar 22 is adjusted. Then, the direction of the arrow e for advancing the material of the dielectric reflection film 30 is adjusted. As a result, the semiconductor layer 14 serves as a mask for the material to be propagated, and prevents the dielectric reflection film 30 from being coated on the first gap 24 and the end portion 16a on the cleaved surface side of the surface-side electrode 16. Then, the lower spacer bar 28 serves as a mask for the material to be advanced so that the second gap 26 and the end face 18a of the rear surface side electrode 18 on the cleavage surface side are not coated with the dielectric reflection film 30. Further, on the cleavage surface 22c, the dielectric reflection film 30 is coated on at least a half region 22d on the upper spacer bar 28 side including the active layer 12.

  Therefore, it is possible to prevent unnecessary dielectric reflection film 30 from adhering to the first gap 24, the end portion 16a of the front surface side electrode 16, the second gap 26, and the end portion 18a of the back surface side electrode 18. Thereby, the appearance defect of the semiconductor laser bar 22 and the characteristic defect of the laser diode 20 can be prevented.

  Then, the dielectric reflection film 30 is coated on the active region 22d on the cleavage surface 22c. For this reason, it is possible to prevent the laser transmission surface and the reflection surface of the cleavage surface 22c of the laser diode 20 from being broken or deteriorated without any problem.

  In addition, using the lower spacer bar 28 as a mask, the dielectric reflection film 30 is intentionally formed on the cleavage surface 22c in at least half of the region 22d on the upper spacer bar 28 side. Thereby, it can suppress that the thickness of the dielectric reflecting film 30 formed near the active layer 12 varies. For this reason, the characteristic defect of the laser diode 20 can be prevented.

  Furthermore, unlike the second method for manufacturing a semiconductor laser device according to the prior art, there is no gap between the cleaved surface side end 16a and the upper spacer bar 28 in the surface side electrode 16. Similarly, in the back surface side electrode 18, there is no gap between the cleaved surface side end 18 a and the lower spacer bar 28.

  Accordingly, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the front surface side electrode 16 and the back surface side electrode 18. Thereby, the appearance defect of the semiconductor laser bar 22 and the characteristic defect of the laser diode 20 can be prevented.

  As shown in FIG. 4, the material of the dielectric reflection film 30 is formed in a direction perpendicular to the cleaved surface 22c in the direction of arrow f inclined from the center of the cleaved surface 22c toward the back surface 10b of the semiconductor substrate 10. You may make it progress. As a result, the spacer bar 28 on the upper side of the semiconductor laser bar 22 can be used as a mask so that the first gap 24 and the edge 16a on the cleaved surface side of the surface side electrode 16 are not coated with the dielectric reflection film 30. In addition, the semiconductor substrate 10 of the semiconductor laser bar 22 can be used as a mask so that the dielectric reflection film 30 is not coated on the second gap 26 and the end face 18a of the rear surface side electrode 18 on the cleavage surface side. For this reason, it can prevent that the unnecessary dielectric reflecting film 30 adheres.

  Then, the dielectric reflective film 30 may be coated by advancing the material of the dielectric reflective film 30 in the direction of the arrow c perpendicular to the cleavage plane 22c. Also in this case, in the surface side electrode 16, there is no gap between the cleaved surface side end portion 16a and the upper spacer bar 28. Similarly, in the back surface side electrode 18, there is no gap between the cleaved surface side end 18 a and the lower spacer bar 28. For this reason, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the front surface side electrode 16 and the back surface side electrode 18.

  Further, the upper spacer bar 28 and the lower spacer bar 28 do not necessarily have to protrude from the cleavage plane 22c. The end portion 28a of the upper spacer bar 28 may be located at a position away from the cleaved surface 22c in a direction perpendicular to the cleaved surface 22c from the cleaved surface side end 16a of the surface-side electrode 16. Then, the end portion 28a of the lower spacer bar 28 may be positioned at a position away from the cleaved surface 22c in a direction perpendicular to the cleaved surface 22c from the cleaved surface side end portion 18a of the back surface side electrode 18. .

  In this way, the upper spacer bar 28 and the lower spacer bar 28 of the semiconductor laser bar 22 can serve as masks for materials that travel in the direction of arrow e or arrow f. Therefore, it is possible to prevent unnecessary dielectric reflection film 30 from adhering to the first gap 24, the end portion 16a of the front surface side electrode 16, the second gap 26, and the end portion 18a of the back surface side electrode 18.

  Here, FIG. 6 is a process diagram showing the main part of the method of manufacturing the semiconductor laser device according to the modification of the first embodiment. In the semiconductor laser device according to this modification, the first gap 24 and the second gap 26 are not provided as in the first method for manufacturing a semiconductor laser device according to the prior art.

  On the other hand, unlike the manufacturing method of the first semiconductor laser device according to the prior art, the upper spacer bar 28 and the lower spacer bar 28 of the semiconductor laser bar 22 are protruded from the cleaved surface 22c. For this reason, in the surface side electrode 16, there is no gap between the cleaved surface side end 16a and the upper spacer bar 28. Similarly, in the back surface side electrode 18, there is no gap between the cleaved surface side end 18 a and the lower spacer bar 28. Therefore, when the dielectric reflection film 30 is coated on the cleaved surface 22c, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the front surface side electrode 16 and the back surface side electrode 18.

Embodiment 2. FIG.
Hereinafter, with respect to the method for manufacturing the semiconductor laser device according to the second embodiment, differences from the first embodiment will be described. FIG. 7 is a process diagram showing the main part of the method of manufacturing the semiconductor laser device according to the second embodiment.

  When the semiconductor laser bar 22 and the spacer bar 28 are stacked, the end 28a of the upper spacer bar (first spacer bar) 28 of the semiconductor laser bar 22 is positioned at the position of the end 16a on the cleaved surface side of the front electrode 16. Then, the end portion 28a of the lower spacer bar (second spacer bar) 28 is positioned at the position of the end portion 18a on the cleavage plane side of the back surface side electrode 18.

  Then, the material of the dielectric reflecting film 30 is advanced in a direction perpendicular to the cleaved surface 22c in the direction of arrow e inclined from the center of the cleaved surface 22c toward the surface 14a of the semiconductor layer 14. Thereby, the dielectric reflecting film 30 is coated on the cleavage surface 22c. As a result, the semiconductor layer 14 serves as a mask for the material to be propagated, and prevents the dielectric reflection film 30 from being coated on the first gap 24 and the end portion 16a on the cleaved surface side of the surface-side electrode 16.

  Therefore, it is possible to prevent the unnecessary dielectric reflecting film 30 from adhering to the first gap 24 and the end portion 16a on the cleaved surface side of the front electrode 16.

  Unlike the second method for manufacturing a semiconductor laser device according to the prior art, there is no gap between the cleaved surface side end 16a and the upper spacer bar 28 in the surface side electrode 16. Similarly, in the back surface side electrode 18, there is no gap between the cleaved surface side end 18 a and the lower spacer bar 28.

  Accordingly, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the front surface side electrode 16 and the back surface side electrode 18. Thereby, the appearance defect of the semiconductor laser bar 22 and the characteristic defect of the laser diode 20 can be prevented.

  When the material of the dielectric reflecting film 30 is advanced in the direction of arrow e, the unnecessary dielectric reflecting film 30 adheres to the second gap 26 and the end 18a on the cleaved surface side of the back surface side electrode 18. There is a fear. In order to cope with this, the material of the dielectric reflecting film 30 is advanced in a direction perpendicular to the cleavage surface 22c in a direction of an arrow f inclined from the center of the cleavage surface 22c toward the back surface 10b of the semiconductor substrate 10. May be. In this case, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the second gap 26 and the end face 18a on the cleavage plane side of the back surface side electrode 18 as a mask for the material on which the semiconductor substrate 10 travels. .

  Alternatively, the dielectric reflecting film 30 may be coated by causing the material of the dielectric reflecting film 30 to advance in the direction of the arrow c perpendicular to the cleavage plane 22c. Also in this case, in the surface side electrode 16, there is no gap between the cleaved surface side end portion 16a and the upper spacer bar 28. Similarly, in the back surface side electrode 18, there is no gap between the cleaved surface side end 18 a and the lower spacer bar 28. For this reason, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the front surface side electrode 16 and the back surface side electrode 18.

Embodiment 3 FIG.
In the following, with respect to the method for manufacturing the semiconductor laser device according to the third embodiment, differences from the first embodiment will be described. FIG. 8 is a process diagram showing the main part of the method of manufacturing the semiconductor laser device according to the third embodiment.

  When the semiconductor laser bar 22 and the spacer bar 28 are stacked, the cleaved surface 22 c of the semiconductor laser bar 22 is protruded with respect to the spacer bar 28. When the dielectric reflecting film 30 is coated, a third gap 32 is formed in the front side electrode 16 between the cleaved surface side end 16a of the front side electrode 16 and the upper spacer bar 28. . In addition, a fourth gap 34 is formed on the surface of the back electrode 18 between the cleaved surface end 18 a of the back electrode 18 and the lower spacer bar 28.

  Then, the material of the dielectric reflection film 30 is advanced in a direction perpendicular to the cleaved surface 22c in the direction of an arrow e inclined from the center of the cleaved surface 22c toward the surface 14a of the semiconductor layer 14 of the semiconductor laser bar. As a result, the semiconductor layer 14 and the surface side electrode 16 serve as a mask for the traveling material, and the first gap 24, the cleaved surface side end 16 a of the surface side electrode 16, and the third gap 32 are subjected to dielectric reflection. The membrane 30 is not coated.

  Therefore, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the first gap 24, the end portion 16a of the surface side electrode 16, and the third gap 32.

  When the material of the dielectric reflecting film 30 is advanced in the direction of the arrow e, the unnecessary dielectric reflecting film 30 is formed in the second gap 26, the end 18a on the cleaved surface side of the back side electrode 18, and the fourth. There is a risk of adhering to the gap 34. In order to cope with this, the material of the dielectric reflection film 30 is formed in a direction perpendicular to the cleavage surface 22c in an f direction inclined from the center of the cleavage surface 22c toward the back surface 10b of the semiconductor substrate 10 of the semiconductor laser bar 22. You may make it progress. In this case, the semiconductor substrate 10 and the back surface side electrode 18 serve as a mask for the traveling material, and an unnecessary dielectric reflection film 30 is formed in the second gap 26, the end portion 18 a of the back side electrode 18, and the fourth gap 34. Can be prevented.

  Here, FIG. 9 is a process diagram showing the main part of the method of manufacturing the semiconductor laser device according to the modification of the third embodiment. In the semiconductor laser device according to this modification, the first gap 24 and the second gap 26 are not provided as in the first method for manufacturing a semiconductor laser device according to the prior art. Also in this case, it is effective to advance the material of the dielectric reflection film 30 in the direction of the arrow e or the direction of the arrow f. It is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the third gap 32 or the fourth gap 34.

Embodiment 4 FIG.
Hereinafter, differences from the first embodiment with respect to the method for manufacturing the semiconductor laser device according to the fourth embodiment will be described. FIG. 10 is a process diagram showing the main part of the method of manufacturing the semiconductor laser device according to the fourth embodiment.

  A plurality of semiconductor laser bars 22 are stacked without using the spacer bar 28. At this time, the front surface side electrode 16 and the rear surface side electrode 18 of the semiconductor laser bars 22 adjacent to each other are brought into contact with each other so that the cleavage surfaces 22c face the same direction.

  Then, the material of the dielectric reflecting film 30 is advanced in a direction perpendicular to the cleaved surface 22c in the direction of arrow e inclined from the center of the cleaved surface 22c toward the surface 14a of the semiconductor layer 14. Thereby, the dielectric reflecting film 30 is coated on the cleavage surface 22c.

  Thereby, it becomes a mask with respect to the material which the semiconductor layer 14 advances, and it can prevent that the unnecessary dielectric reflecting film 30 adheres to the edge part 16a by the side of the cleavage surface of the 1st clearance gap 24 and the surface side electrode 16. .

  Further, the front surface side electrode 16 and the back surface side electrode 18 of the semiconductor laser bars 22 adjacent to each other of the plurality of semiconductor laser bars 22 are in contact with each other. For this reason, there is no gap in the front surface side electrode 16 and the back surface side electrode 18.

  Accordingly, it is possible to prevent the unnecessary dielectric reflection film 30 from adhering to the front surface side electrode 16 and the back surface side electrode 18. Thereby, the appearance defect of the semiconductor laser bar 22 and the characteristic defect of the laser diode 20 can be prevented.

  When the material of the dielectric reflecting film 30 is advanced in the direction of arrow e, the unnecessary dielectric reflecting film 30 adheres to the second gap 26 and the end 18a on the cleaved surface side of the back surface side electrode 18. There is a fear. Therefore, the material of the dielectric reflection film may be advanced in a direction perpendicular to the cleaved surface 22c in the direction of arrow f inclined from the center of the cleaved surface 22c toward the back surface 10b side of the semiconductor substrate 10. Thereby, it becomes a mask with respect to the material which the semiconductor substrate 10 advances, and it can prevent that the unnecessary dielectric reflective film 30 adheres to the edge part 18a by the side of the cleavage surface of the 2nd clearance gap 26 and the back surface side electrode 18. .

  Here, FIG. 11 is a process diagram showing the main part of the manufacturing method of the semiconductor laser device according to the modification of the fourth embodiment. In the semiconductor laser device according to this modification, the first gap 24 and the second gap 26 are not provided as in the first method for manufacturing a semiconductor laser device according to the prior art. Also in this case, the plurality of semiconductor laser bars 22 are overlapped so that the front surface side electrode 16 and the back surface side electrode 18 of the semiconductor laser bars 22 adjacent to each other are in contact with each other. For this reason, there is no gap in the front surface side electrode 16 and the back surface side electrode 18. Therefore, when the dielectric reflection film 30 is coated on the cleaved surface 22c, unnecessary dielectric reflection film 30 can be prevented from adhering to the front surface side electrode 16 and the back surface side electrode 18.

10 Semiconductor substrate 12 Active layer 14 Semiconductor layer 16 Front side electrode 18 Back side electrode 20 Laser diode 22 Semiconductor laser bar 24 First gap 26 Second gap 28 Spacer bar 30 Dielectric reflection film 32 Third gap 34 Fourth Gap

Claims (7)

Forming a semiconductor layer including an active layer on the surface side of the semiconductor substrate;
Forming a plurality of surface side electrodes separated from each other so as to be aligned in a first direction and a second direction intersecting the first direction on the surface of the semiconductor layer;
Forming a plurality of backside electrodes spaced apart from each other so as to line up at positions facing the frontside electrodes on the backside of the semiconductor substrate;
Forming the semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode;
Coating the dielectric reflective film on the cleaved surface of the semiconductor laser bar while sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate by the first and second spacer bars in a rectangular parallelepiped ; When,
With
When forming the semiconductor laser bar, on the surface of the semiconductor layer of the semiconductor laser bar, a first gap is formed between the cleaved surface and an end of the surface-side electrode on the cleaved surface side, and the semiconductor laser bar is formed. In the back surface of the semiconductor substrate of the laser bar, a second gap is formed between the cleavage surface and an end of the back surface side electrode on the cleavage surface side,
When coating the dielectric reflecting film, the end portions of the first and second spacer bars are perpendicular to the cleaved surface from the cleaved surface side end portions of the front surface side electrode and the back surface side electrode. And so that it is in a position away from the cleavage plane ,
When coating the dielectric reflection film, the dielectric is set in a direction in which a direction perpendicular to the cleavage plane of the semiconductor laser bar is inclined from a center of the cleavage plane toward a surface side of the semiconductor layer of the semiconductor laser bar. A method of manufacturing a semiconductor laser device, wherein the material of the reflective film is advanced . 2. The method of manufacturing a semiconductor laser device according to claim 1 , wherein when coating the dielectric reflection film, the second spacer bar protrudes from the cleaved surface. 3. In the cleavage plane, at least half of the region including the active layer on the first spacer bar side is coated with the dielectric reflection film, and the first gap, the end of the surface-side electrode on the cleavage plane side. , The second gap, and a width for projecting the second spacer bar so that the dielectric reflective film is not coated on the cleaved surface side end of the back electrode, and the dielectric reflective film The method of manufacturing a semiconductor laser device according to claim 2 , wherein a direction in which the material is advanced is adjusted. Forming a semiconductor layer including an active layer on the surface side of the semiconductor substrate;
Forming a plurality of surface side electrodes separated from each other so as to be aligned in a first direction and a second direction intersecting the first direction on the surface of the semiconductor layer;
Forming a plurality of backside electrodes spaced apart from each other so as to line up at positions facing the frontside electrodes on the backside of the semiconductor substrate;
Forming the semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode;
Coating the dielectric reflective film on the cleaved surface of the semiconductor laser bar while sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate by the first and second spacer bars in a rectangular parallelepiped; When,
With
When forming the semiconductor laser bar, on the surface of the semiconductor layer of the semiconductor laser bar, a first gap is formed between the cleaved surface and an end of the surface-side electrode on the cleaved surface side, and the semiconductor laser bar is formed. In the back surface of the semiconductor substrate of the laser bar, a second gap is formed between the cleavage surface and an end of the back surface side electrode on the cleavage surface side,
When coating the dielectric reflecting film, the end portions of the first and second spacer bars are perpendicular to the cleaved surface from the cleaved surface side end portions of the front surface side electrode and the back surface side electrode. And so that it is in a position away from the cleavage plane,
When coating the dielectric reflection film, the dielectric is set in such a direction that a direction perpendicular to the cleaved surface of the semiconductor laser bar is inclined from a center of the cleaved surface toward a back side of the semiconductor substrate of the semiconductor laser bar. method of manufacturing a semi-conductor laser element you characterized by advancing the material of the reflective film. 5. The method of manufacturing a semiconductor laser device according to claim 4 , wherein when coating the dielectric reflection film, the first spacer bar is protruded with respect to the cleavage plane. Forming a semiconductor layer including an active layer on the surface side of the semiconductor substrate;
Forming a plurality of surface side electrodes separated from each other so as to be aligned in a first direction and a second direction intersecting the first direction on the surface of the semiconductor layer;
Forming a plurality of backside electrodes spaced apart from each other so as to line up at positions facing the frontside electrodes on the backside of the semiconductor substrate;
Forming the semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode;
Coating the dielectric reflective film on the cleaved surface of the semiconductor laser bar while sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate by the first and second spacer bars in a rectangular parallelepiped ; When,
With
When forming the semiconductor laser bar, on the surface of the semiconductor layer of the semiconductor laser bar, a first gap is formed between the cleaved surface and an end of the surface side electrode on the cleaved surface side,
When coating the dielectric reflection film, on the surface of the surface-side electrode, a second gap is formed between the cleaved surface side end of the surface-side electrode and the first spacer bar,
When coating the dielectric reflection film, the dielectric is set in a direction in which a direction perpendicular to the cleavage plane of the semiconductor laser bar is inclined from a center of the cleavage plane toward a surface side of the semiconductor layer of the semiconductor laser bar. A method of manufacturing a semiconductor laser device, wherein the material of the reflective film is advanced. Forming a semiconductor layer including an active layer on the surface side of the semiconductor substrate;
Forming a plurality of surface side electrodes separated from each other so as to be aligned in a first direction and a second direction intersecting the first direction on the surface of the semiconductor layer;
Forming a plurality of backside electrodes spaced apart from each other so as to line up at positions facing the frontside electrodes on the backside of the semiconductor substrate;
Forming the semiconductor laser bar by cleaving the semiconductor substrate along the first direction at a position away from the front surface side electrode and the back surface side electrode;
Coating the dielectric reflective film on the cleaved surface of the semiconductor laser bar while sandwiching the semiconductor laser bar from the front surface side of the semiconductor layer and the back surface side of the semiconductor substrate by the first and second spacer bars in a rectangular parallelepiped ; When,
With
When forming the semiconductor laser bar, on the back surface of the semiconductor substrate of the semiconductor laser bar, a first gap is formed between the cleaved surface and an end of the back surface side electrode on the cleaved surface side,
When coating the dielectric reflection film, on the surface of the back electrode, a second gap is formed between the cleaved surface side end of the back electrode and the second spacer bar,
When coating the dielectric reflection film, the dielectric is set in such a direction that a direction perpendicular to the cleaved surface of the semiconductor laser bar is inclined from a center of the cleaved surface toward a back side of the semiconductor substrate of the semiconductor laser bar. A method of manufacturing a semiconductor laser device, wherein the material of the reflective film is advanced .

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