Semiconductor device

Abstract

A semiconductor device includes an end surface coated with a film, an upper surface disposed substantially orthogonally to the end surface, an electrode disposed substantially across the upper surface, an identifying mark disposed on the upper surface, and a protruding portion of the electrode which is disposed between the identifying mark and a plane substantially defined by the end surface, wherein the protruding portion has a thickness measured along an axis orthogonal to the upper surface which is greater than or equal to a thickness of the identifying mark measured along the axis.

Description

SEMICONDUCTOR DEVICECROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 739,343 filed December 27, 2024 the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a semiconductor device.

[0003] For example, PTL 1 discloses a semiconductor element having a two-dimensional code formed on a surface.

[0004] PTL 1: Japanese Unexamined Patent Application Publication No. 2010-199423Summary

[0005] Incidentally, in a semiconductor device, an improvement in manufacturing yield is demanded.

[0006] It is desirable to provide a semiconductor device that makes it possible to improve a manufacturing yield.

[0007] A semiconductor device according to an example embodiment of the present disclosure includes an end surface coated with a film, an upper surface disposed substantially orthogonally to the end surface, an electrode disposed substantially across the upper surface, an identifying mark disposed on the upper surface, and a protruding portion of the electrode which is disposed between the identifying mark and a plane substantially defined by the end surface, wherein the protruding portion has a thickness measured along an axis orthogonal to the upper surface which is greater than or equal to a thickness of the identifying mark measured along the axis.

[0008] The semiconductor device according to the embodiment of the present disclosure includes the semiconductor light-emitting element including the first surface and the second surface opposed to each other and the pair of end surfaces opposed to each other and each having the normal line that intersects the normal line of the first surface, and is provided with the protection object structure on the first surface. In such a semiconductor light-emitting element, the extending part that is the extension of the electrode film is also provided on the first surface, between the protection object structure and one of the pair of end surfaces. This makes it possible to prevent, when an end surface coating film such as a multilayer reflective film is formed on an end surface of the semiconductor light-emitting element, for example, formation of the end surface coating film on the protection object structure caused by spreading of the end surface coating film.

[0009] Fig. 1 is a perspective diagram illustrating a configuration example of a semiconductor device according to an embodiment of the present disclosure.Fig. 2 is an exploded perspective diagram of the semiconductor device illustrated in Fig. 1.Fig. 3 is a schematic diagram illustrating a front surface configuration example of the semiconductor device illustrated in Fig. 1.Fig. 4 includes an upper surface diagram (A) and a cross-sectional diagram (B) of the semiconductor device illustrated in Fig. 1.Fig. 5 is a diagram for explaining a step of forming an end surface coating film of a general semiconductor device.Fig. 6 is a diagram for explaining spreading of the end surface coating film formed as in Fig. 5 to an upper surface of a semiconductor laser element.Fig. 7 is a diagram for explaining a step of forming an end surface coating film of the semiconductor device illustrated in Fig. 1.Fig. 8 is a diagram for explaining spreading of the end surface coating film formed as in Fig. 7 to an upper surface of a semiconductor laser element.Fig. 9 includes an upper surface diagram (A) and a cross-sectional diagram (B) each illustrating a configuration example of a semiconductor laser element according to Modification example 1 of the present disclosure.Fig. 10 includes an upper surface diagram (A) and a cross-sectional diagram (B) each illustrating a configuration example of a semiconductor laser element according to Modification example 2 of the present disclosure.Fig. 11 includes an upper surface diagram (A) and a cross-sectional diagram (B) each illustrating a configuration example of a semiconductor laser element according to Modification example 3 of the present disclosure.Fig. 12 is a perspective diagram illustrating a configuration example of a semiconductor device according to Modification example 4 of the present disclosure.

[0010] Hereinafter, description is given in detail of embodiments of the present disclosure with reference to the drawings.

[0011] The drawings to be referred to in the following description are intended to describe embodiments of the present disclosure and facilitate understanding thereof; shapes, dimensions, ratios, and the like illustrated in the drawings may differ from actual ones, in some cases, for better understanding. Further, the design of the semiconductor device illustrated in the drawings can be modified as appropriate by taking into consideration the following description and known techniques. In addition, in the description using the cross-sectional diagram of the semiconductor device, the up / down direction of the stacked structure of the semiconductor device corresponds to a relative direction in a case where an upper electrode to be wire-bonded is defined as being the top. The up / down direction may differ, in some cases, from an up / down direction that is compliant with the actual gravitational acceleration.

[0012] In the following description, expressions regarding a size and a shape do not only mean the same values as a numerical value defined mathematically or a shape defined geometrically. The expressions regarding a size and a shape also include a shape in a case of having an industrially acceptable difference in a step of manufacturing the semiconductor device or even a shape similar thereto.

[0013] In the description of the semiconductor device, unless otherwise specified, "coupling" means electrical coupling between a plurality of elements. Additionally, "coupling" in the following description includes not only a case of coupling a plurality of elements directly and electrically, but also a case of coupling the plurality of elements indirectly and electrically via another element. It is to be noted that the description is given in the following order. 1. Embodiment (An example of a semiconductor device including an extending part for preventing spreading of an end surface coating film between a protection object structure and a resonator end surface) 2. Modification Examples 2-1. Modification Example 1 (Another example of a configuration of a semiconductor laser element) 2-2. Modification Example 2 (Another example of the configuration of the semiconductor laser element) 2-3. Modification Example 3 (Another example of the configuration of the semiconductor laser element) 2-4. Modification Example 4 (Another example of a configuration of the semiconductor device) <1. Embodiment>

[0014] Fig. 1 is a perspective diagram illustrating a configuration example of a semiconductor device 1 according to an embodiment of the present disclosure. Fig. 2 is an exploded perspective diagram of the semiconductor device 1 illustrated in Fig. 1. Fig. 3 schematically illustrates a front surface configuration of the semiconductor device 1 illustrated in Fig. 1. The semiconductor device 1 is used, for example, as a light source or a heat source of an electronic apparatus.

[0015] The semiconductor device 1 is, for example, a device in which a semiconductor laser element 10 is mounted on a mounting surface Sb1 of a submount 30. The semiconductor laser element 10 includes a pair of surfaces (an upper surface 10S1 and a lower surface 10S2) opposed to each other, and a pair of end surfaces (resonator end surfaces Sa1 and Sa2) opposed to each other. The resonator end surfaces Sa1 and Sa2 each have a normal line that intersects a normal line of the upper surface 10S1, for example. An upper electrode 117 and a two-dimensional code 20 are provided on the upper surface 10S1 of the semiconductor laser element 10. An extending part X1 that is an extension of the upper electrode 117 is provided between the two-dimensional code 20 and the resonator end surface Sa1.

[0016] Here, the semiconductor laser element 10 corresponds to a specific example of a "semiconductor light-emitting element" according to one embodiment of the present disclosure. The upper surface 10S1 corresponds to a specific example of a "first surface" according to one embodiment of the present disclosure, and the lower surface 10S2 corresponds to a specific example of a "second surface" according to one embodiment of the present disclosure. The upper electrode 117 corresponds to a specific example of an "electrode film" according to one embodiment of the present disclosure. The two-dimensional code 20 corresponds to a specific example of a "protection object structure" according to one embodiment of the present disclosure. The submount 30 corresponds to a specific example of a "bonding object" according to one embodiment of the present disclosure. {Configuration of Semiconductor Device}

[0017] The semiconductor device 1 includes the semiconductor laser element 10, the two-dimensional code 20, the submount 30, solder 40, an external electrode Eb, and a coupling electrode Ec.

[0018] The semiconductor laser element 10 is, for example, a type of edge-emitting semiconductor laser element, and includes the pair of end surfaces (the resonator end surfaces Sa1 and Sa2) opposed to each other in a resonator direction. The resonator end surface Sa1 is, for example, a light output surface through which a laser beam is outputted to the outside. The semiconductor laser element 10 further includes: a ridge part 11 extending in a direction in which the resonator end surfaces Sa1 and Sa2 are opposed to each other (here, a Y-axis direction); and a pair of trenches 12 that allows the ridge part 11 to be provided. The resonator end surfaces Sa1 and Sa2 are surfaces formed by cleaving. The resonator end surfaces Sa1 and Sa2 function as resonator mirrors, and the ridge part 11 functions as an optical waveguide. The semiconductor laser element 10 further includes a pair of side surfaces Sa3 and Sa4 opposed to each other in a direction orthogonal to an extending direction of the ridge part 11.

[0019] As illustrated in Fig. 3, the semiconductor laser element 10 includes, for example, a semiconductor stack section 110 in which a substrate 111, a buffer layer 112, a lower clad layer 113, an active layer 114, an upper clad layer 115, and a contact layer 116 are stacked in this order. The semiconductor stack section 110 corresponds to a specific example of a "semiconductor layer" according to one embodiment of the present disclosure. An upper surface of the semiconductor stack section 110 (an upper surface of the contact layer 116) is referred to as the upper surface 10S1 of the semiconductor laser element 10, and a lower surface of the semiconductor stack section 110 (a surface, of the substrate 111, opposite to a surface on which the above-described semiconductor layers are formed) is referred to as the lower surface 10S2. The ridge part 11 is provided on the upper surface 10S1 of the semiconductor laser element 10. For example, each of the pair of trenches 12 that allows the ridge part 11 to be provided penetrates the contact layer 116 and has a bottom surface in layers of the upper clad layer 115. The semiconductor laser element 10 further includes the upper electrode 117 on the contact layer 116 of the ridge part 11, and further includes a lower electrode 118 on a back surface of the substrate 111. The semiconductor laser element 10 further includes a dielectric film 13. The dielectric film 13 is provided on side surfaces and the bottom surfaces of the pair of trenches 12 as well as the contact layer 116 positioned outside the pair of trenches 12. The semiconductor laser element 10 may further include an end surface coating film 14 (for example, see Fig. 8). The end surface coating film 14 is provided on each of the resonator end surfaces Sa1 and Sa2.

[0020] The semiconductor stack section 110 includes, for example, a group III-V compound semiconductor such as gallium arsenide (GaAs). Here, the term "group III-V semiconductor" refers to a semiconductor including: at least one element out of group 3B elements (at least one element out of Ga, Al, In, and B) in the short-form periodic table; and at least As out of group 5B elements in the short-form periodic table. Examples of the group III-V compound semiconductor include gallium arsenide-based compounds including gallium (Ga) and arsenic (As). Examples of the gallium arsenide-based compounds include gallium arsenide (GaAs), aluminum gallium arsenide (AlGaAs), indium gallium arsenide (InGaAs), and the like. The group III-V compound semiconductor is doped with an n-type impurity of a group IV or group VI element such as silicon (Si), germanium (Ge), oxygen (O), or selenium (Se), or with a p-type impurity of a group II or group IV element such as magnesium (Mg), zinc (Zn), or carbon (C), as necessary.

[0021] For example, the substrate 111 may be a group III-V compound semiconductor substrate such as a GaAs substrate. The substrate 111 may be an aluminum nitride (AlN) substrate, a sapphire substrate, a silicon carbide (SiC) substrate, a Si substrate, or a zirconium oxide (ZrO) substrate.

[0022] The buffer layer 112 is adapted to mitigate a lattice mismatch between the substrate 111 and the lower clad layer 113. In a case where the substrate 111 and the lower clad layer 113 have different lattice constants, the buffer layer 112 is controlled in the lattice constant to have a more favorable crystalline state. This makes it possible to suppress a crystal defect and further prevent warping of the substrate 111. The buffer layer 112 is formed on, for example, a main surface of the substrate 111, and includes, for example, a semiconductor layer (an n-type semiconductor layer) having n-type conductivity. The buffer layer 112 includes, for example, one of a GaAs layer and an AlGaAs layer, or at least two layers of any of these layers. The buffer layer 112 includes, for example, Si as a dopant adapted to provide n-type conductivity.

[0023] The lower clad layer 113 corresponds to a specific example of a "first-conductivity-type layer" according to one embodiment of the present disclosure. The lower clad layer 113 is formed on, for example, the buffer layer 112, and includes, for example, a semiconductor layer (an n-type semiconductor layer) having n-type conductivity. The lower clad layer 113 includes, for example, an AlGaAs layer. The lower clad layer 113 includes, for example, Si as a dopant adapted to provide n-type conductivity.

[0024] The active layer 114 corresponds to a specific example of an "active layer" according to one embodiment of the present disclosure. The active layer 114 is formed on, for example, the lower clad layer 113. The active layer 114 is provided between the lower clad layer 113 and the upper clad layer 115. The active layer 114 has, for example, a multi-well structure in which barrier layers and well layers are alternately stacked. The active layer 114 may have a multi-quantum well structure.

[0025] Each well layer includes Ga and a group III-V compound semiconductor. Each well layer includes a non-doped semiconductor layer. Each well layer generates a photon having a wavelength of 780 nm to 1700 nm, for example.

[0026] Each barrier layer includes a group III-V compound semiconductor. Each barrier layer includes a non-doped semiconductor layer. The barrier layer has a bandgap having a value greater than or equal to, for example, a maximum bandgap of each well layer.

[0027] The upper clad layer 115 corresponds to a specific example of a "second-conductivity-type layer" according to one embodiment of the present disclosure. The upper clad layer 115 is formed on the active layer 114. The upper clad layer 115 includes, for example, a semiconductor layer (a p-type semiconductor layer) having p-type conductivity. The upper clad layer 115 includes, for example, an AlGaAs layer. The upper clad layer 115 includes, for example, C as a dopant adapted to provide p-type conductivity.

[0028] The contact layer 116 is formed on, for example, the upper clad layer 115, and includes, for example, a semiconductor layer (a p-type semiconductor layer) having p-type conductivity. The contact layer 116 includes, for example, one of a GaAs layer and an AlGaAs layer, or at least two layers of any of these layers. The contact layer 116 includes, for example, C as a dopant adapted to provide p-type conductivity.

[0029] The pair of trenches 12 allows the ridge part 11 to be provided on an upper part of the semiconductor stack section 110, specifically, on the contact layer 116 and a part of the upper clad layer 115. The ridge part 11 extends in one direction (the resonator direction) in a stacking plane of the semiconductor stack section 110. In other words, the ridge part 11 extends in the direction in which the resonator end surfaces Sa1 and Sa2 are opposed to each other (here, the Y-axis direction), as described above. Further, in other words, the ridge part 11 is considered as being sandwiched between the pair of resonator end surfaces Sa1 and Sa2 of the semiconductor stack section 110. The ridge part 11 is formed by, for example, performing etching removal from the upper surface of the contact layer 116 to the middle of the upper clad layer 115.

[0030] The upper electrode 117 is formed on the upper surface 10S1 of the semiconductor laser element 10. Specifically, in the ridge part 11, the upper electrode 117 is formed in contact with the contact layer 116 included in the semiconductor stack section 110. Outside the ridge part 11, the upper electrode 117 is formed over a part, of the contact layer 116, positioned outside the pair of trenches 12 that allows the ridge part 11 to be provided, as well as the side surfaces and the bottom surfaces of the pair of trenches 12, via the dielectric film 13. The upper electrode 117 applies a voltage to the active layer 114 from a side close to the upper clad layer 115, and also serves as, for example, a metal layer to which the bonding wire is bonded. The upper electrode 117 has, for example, a configuration in which a titanium (Ti) layer, a platinum (Pt) layer, and a gold (Au) layer are stacked in this order from a side close to the contact layer 116. It is sufficient for the upper electrode 117 to be electrically coupled to the contact layer 116, and a layer configuration of the upper electrode 117 is not limited to the configuration described above.

[0031] For example, the lower electrode 118 is formed in contact with a lower surface of the substrate 111. The lower electrode 118 applies a voltage to the active layer 114 from a side close to the lower clad layer 113. The lower electrode 118 has, for example, a configuration in which an AuGe layer, a Ni layer, and an Au layer are stacked in this order from a side close to the substrate 111. It is sufficient for the lower electrode 118 to be electrically coupled to the substrate 111, and a layer configuration of the lower electrode 118 is not limited to the configuration described above. Further, the lower electrode 118 may be in contact with the entirety of the lower surface of the substrate 111, or may be in contact with only a part of the lower surface of the substrate 111.

[0032] The dielectric film 13 covers the side surfaces and the bottom surfaces of the pair of trenches 12 that allows the ridge part 11 to be provided, as well as a part, of the upper surface 10S1 of the semiconductor stack section 110, positioned outside the pair of trenches 12. The dielectric film 13 corresponds to a specific example of a "first dielectric film" according to one embodiment of the present disclosure. The dielectric film 13 includes, for example, silicon oxide (SiO2).

[0033] The resonator end surfaces Sa1 and Sa2 may each be provided with the end surface coating film 14, as described above. The end surface coating film 14 is, for example, a multilayer reflective film or an antireflection film. The multilayer reflective film includes, for example, a dielectric such as SiO2, titanium oxide (TiO2), tantalum oxide (Ta2O5), or silicon nitride (SiN). The multilayer reflective film is provided on the resonator end surface Sa1 serving as the light output surface. The antireflection film includes, for example, a dielectric (e.g., SiO2, TiO2, Ta2O5, SiN, or the like) and Si. The antireflection film is provided on the resonator end surface Sa2.

[0034] In the semiconductor laser element 10 of the present embodiment, when a predetermined voltage is applied between the upper electrode 117 and the lower electrode 118, a current is injected into the active layer 114, which causes light emission to be generated due to recombination of electrons and holes. The light is repeatedly reflected by the pair of resonator end surfaces Sa1 and Sa2 and then outputted from one of the end surfaces (the resonator end surface Sa1) as a laser beam of a predetermined wavelength. In this way, laser oscillation is performed.

[0035] The two-dimensional code 20 is used for identifying, even after the semiconductor laser element 10 has been incorporated into the semiconductor device 1, the semiconductor laser element 10 to thereby link thereto electric property data, address information in a crystalline substrate, or manufacturing information such as manufacturing conditions. The two-dimensional code 20 is, for example, a matrix code formed such that squares arranged in upper, lower, left, and right directions protrude or are recessed from the upper surface 10S1 of the semiconductor laser element 10. The two-dimensional code 20 is formed, for example, by etching the dielectric film 13 down to the contact layer 116 by photolithography and etching in a step prior to the semiconductor laser element 10 being cut out from a semiconductor wafer by dicing or the like. That is, the two-dimensional code 20 includes the dielectric film 13 and the contact layer 116. In addition, the two-dimensional code 20 is formable by using, for example, laser marking.

[0036] The two-dimensional code 20 corresponds to a specific example of a "protection object structure" according to one embodiment of the present disclosure; however, this is non-limiting. The protection object structure may include, for example, a bar code, a letter, a number, a symbol, or a combination thereof.

[0037] Fig. 4 schematically illustrates respective configurations of an upper surface (A) and a cross section (B) of the semiconductor laser element 10 illustrated in Fig. 1. In the present embodiment, as described above, the extending part X1 is provided between the two-dimensional code 20 and the resonator end surface Sa1. As will be described in detail later, the extending part X1 prevents the following from occurring: in a step prior to singulating the semiconductor laser element 10, of collectively forming the end surface coating film 14 on each of respective end surfaces (e.g., the respective resonator end surfaces Sa1) of a plurality of semiconductor laser bars (hereinafter, referred to as a plurality of laser bars 100) each cut in a band-plate shape from the semiconductor wafer as illustrated in Fig. 7, for example, the end surface coating film 14 spreads on the upper surface 10S1 of the semiconductor laser element 10, and the end surface coating film 14 is thereby formed on the two-dimensional code 20 as illustrated in Fig. 6, for example. The extending part X1 is an extension of the upper electrode 117. This makes it possible, as illustrated in Fig. 8, for example, to avoid being unable to read the two-dimensional code 20 due to formation of the end surface coating film 14 on the two-dimensional code 20 caused by the spreading of the end surface coating film 14, without adding any steps.

[0038] For example, as illustrated in Fig. 4, in a case where the two-dimensional code 20 is formed closer to either one of the pair of resonator end surfaces Sa1 and Sa2, the extending part X1 is provided between one of the end surfaces that is on a side closer to the two-dimensional code 20 (here, the resonator end surface Sa1) and the two-dimensional code 20. A width (a width W1) of the extending part X1 in an extending direction (here, an X-axis direction) is preferably wider than a width W2 of the two-dimensional code 20. This makes it possible to further prevent the spreading of the end surface coating film 14 on the upper surface 10S1 of the semiconductor laser element 10.

[0039] The submount 30 includes a block 31. The block 31 includes the mounting surface Sb1 on which the semiconductor laser element 10 is mounted and a bonding end surface Sb2 having a normal line that intersects a normal line of the mounting surface Sb1. The block 31 further includes, as surfaces thereof, a non-bonding end surface Sb3 and a pair of side surfaces Sb4 and Sb5. The non-bonding end surface Sb3 is opposed to the bonding end surface Sb2. The pair of side surfaces Sb4 and Sb5 each have a normal line that intersects each of the normal line of the mounting surface Sb1 and the normal line of the bonding end surface Sb2. The block 31 includes an insulating material having a high heat dissipation property. The block 31 includes, for example, AlN, Si, SiC, copper (Cu), tungsten (W), molybdenum (Mo), aluminum (Al), diamond, a composite material including any of these materials, or the like. Examples of such a composite material include Cu-W, Al-SiC, and the like.

[0040] The bonding end surface Sb2, the non-bonding end surface Sb3, and the side surfaces Sb4 and Sb5 are side surfaces of the block 31. The block 31 is larger in size than the semiconductor laser element 10. Specifically, the mounting surface Sb1 of the block 31 is larger in size than the lower electrode 118 of the semiconductor laser element 10. The semiconductor laser element 10 is so bonded to the mounting surface Sb1 that, for example, the ridge part 11 is at a position opposed to a center position, of the mounting surface Sb1, in a width direction of the ridge part 11. For example, the resonator end surface Sa1 is disposed at a position close to the bonding end surface Sb2. For example, the resonator end surface Sa2 is disposed at a position distant from the non-bonding end surface Sb3, as compared with a distance between the resonator end surface Sa1 and the bonding end surface Sb2. For example, the side surface Sa3 is disposed at a position close to the side surface Sb4. For example, the side surface Sa4 is disposed at a position distant from the side surface Sb5, as compared with a distance between the side surface Sa3 and the side surface Sb4. The position of the semiconductor laser element 10 on the mounting surface Sb1 is not limited to the position described above.

[0041] The bonding end surface Sb2 is, for example, a bonding surface to be bonded to an external component. The semiconductor laser element 10 is bonded to the external component via the submount 30.

[0042] The bonding end surface Sb2 is provided with a bonding metal layer 32. The bonding metal layer 32 is bonded to the external component via, for example, a solder. The bonding metal layer 32 includes, for example, Ti, Pt, and Au in this order from a side closer to the bonding end surface Sb2. It is sufficient for the bonding metal layer 32 to be able to be in close contact with the bonding end surface Sb2, and a layer configuration of the bonding metal layer 32 is not limited to the configuration described above.

[0043] The mounting surface Sb1 is provided with the coupling electrode Ec and the external electrode Eb. The lower electrode 118 of the semiconductor laser element 10 is bonded to the coupling electrode Ec via the solder 40. The external electrode Eb is, for example, a metal layer to which the bonding wire is bonded. The coupling electrode Ec and the external electrode Eb each include, for example, Ti, Pt, and Au in this order from a side closer to the block 31. It is sufficient for each of the coupling electrode Ec and the external electrode Eb to be able to be in close contact with the mounting surface Sb1 of the block 31, and a layer configuration of each of the coupling electrode Ec and the external electrode Eb is not limited to the configuration described above.

[0044] The solder 40 is for mounting the semiconductor laser element 10 on the submount 30. The solder 40 is, for example, so provided between the lower electrode 118 and the coupling electrode Ec as to bond the lower surface 10S2 of the semiconductor laser element 10 and the mounting surface Sb1 of the submount 30 to each other. The solder 40 includes, for example, AuSn (gold-tin). That is, the semiconductor laser element 10 and the submount 30 are eutectically bonded to each other by, for example, AuSn. The semiconductor laser element 10 and the submount 30 may be bonded to each other by a silver (Ag) paste, sintered gold (Au), sintered silver (Ag), or the like. {Method of Manufacturing Semiconductor Laser Element}

[0045] The semiconductor laser element 10 is manufacturable, for example, as follows.

[0046] First, the substrate 111 including, for example, GaAs is prepared in a reactor. Thereafter, the buffer layer 112, the lower clad layer 113, the active layer 114, the upper clad layer 115, and the contact layer 116 are formed in this order on an upper surface (a crystal-growth surface) of the substrate 111 by, for example, organometallic chemical vapor deposition (MOCVD).

[0047] When MOCVD is performed, used as a source gas of gallium is, for example, trimethylgallium ((CH3)3Ga), and used as a source gas of aluminum is, for example, trimethylaluminum ((CH3)3Al). Further, used as a source gas of arsenic is arsine (AsH3). Further, used as a source gas of silicon is, for example, monosilane (SiH4), and used as a source gas of carbon is, for example, carbon tetrabromide (CBr4).

[0048] Thereafter, the contact layer 116 and a part of the upper clad layer 115 are selectively removed by, for example, reactive ion-etching (RIE) to form the pair of trenches 12. As a result, the ridge part 11 having a thin band shape is formed on an upper part of the upper clad layer 115 and the contact layer 116.

[0049] Thereafter, a film of the dielectric film 13 is formed on the upper clad layer 115 and the contact layer 116, following which an opening is provided correspondingly to an upper surface of the ridge part 11. Thereafter, a film of the metal material is formed by, for example, a vapor deposition method or a sputtering method, following which the film is patterned into a desired shape by, for example, etching using a photolithography method to thereby form the upper electrode 117 including the extending part X1. Thereafter, a back surface side of the substrate 111 is lapped and polished, for example, to cause the substrate 111 to have a predetermined thickness, following which the lower electrode 118 is formed on the back surface of the substrate 111.

[0050] Thereafter, as illustrated in Fig. 7, for example, the plurality of laser bars 100 is fixed by jigs, and the end surface coating film 14 is formed on each of the pair of resonator end surfaces Sa1 and Sa2 by, for example, vapor deposition or sputtering. Thereafter, for example, the plurality of laser bars 100 is diced and singulated for each semiconductor laser element 10. In this way, the semiconductor laser element 10 is completed. {Workings and Effects}

[0051] The semiconductor device 1 according to the present embodiment is provided with the upper electrode 117 and the two-dimensional code 20 on the upper surface 10S1 of the semiconductor laser element 10, and is also provided with the extending part X1 that is the extension of the upper electrode 117. The extending part X1 is provided between the two-dimensional code 20 and the resonator end surface Sa1 out of the pair of resonator end surfaces Sa1 and Sa2, which is positioned closer to the two-dimensional code 20. This prevents, when the end surface coating film 14 is formed on the resonator end surface Sa1 of the semiconductor laser element 10, formation of the end surface coating film 14 on the two-dimensional code 20 caused by the spreading of the end surface coating film 14. This will be described below.

[0052] As described above, even after the semiconductor element has been incorporated into the semiconductor device, the semiconductor element is identified and marked with identification information (e.g., a two-dimensional code) to link thereto electric property data, address information in a crystalline substrate, or manufacturing information such as manufacturing conditions.

[0053] Fig. 5 illustrates a step of forming an end surface coating film 54 on the resonator end surface Sa1 of a general semiconductor laser element (a semiconductor laser element 50, for example, see Fig. 6). As illustrated in Fig. 5, for example, the end surface coating film 54 is formed as follows. A plurality of laser bars 500 prior to singulating the semiconductor laser element 50 each cut in a band-plate shape from the semiconductor wafer is fixed by jigs, and the end surface coating film 54 is formed by, for example, vapor deposition or sputtering. At this time, measures are taken to prevent spreading of the end surface coating film 54 on an upper surface of each of the laser bars 500 by, for example, a way in which the laser bars 500 are set by the jigs. However, when an amount of spreading of the end surface coating film 54 is large, as illustrated in Fig. 6, for example, the end surface coating film 54 is also formed on identification information (a two-dimensional code 60) marked in advance on the upper surface of each of the laser bars 500 for each element, which makes it difficult to read the identification information.

[0054] Proposed as a method to prevent reduction in reading accuracy of the identification information due to spreading of the end surface coating film 54 is, for example, a method including forming a plated layer on a laser bar and marking identification information on the plated layer. However, the method described above has issues with an increase in tact time due to an increase in the number of steps and an increase in manufacturing cost.

[0055] In contrast, in the present embodiment as described above, provided between the two-dimensional code 20 provided on the upper surface 10S1 of the semiconductor laser element 10 and the resonator end surface Sa1 is the extending part X1 that is also provided on the upper surface 10S1 and is the extension of the upper electrode 117. Thus, as illustrated in Fig. 7, for example, when the plurality of laser bars 100 is fixed by jigs and the end surface coating film 14 is formed on the resonator end surface Sa1 by, for example, vapor deposition or sputtering, even if the amount of spreading of the end surface coating film 14 increases, the extending part X1 makes it possible to prevent formation of the end surface coating film 14 on the two-dimensional code 20, as illustrated in Fig. 8, for example, without increasing the number of steps.

[0056] Therefore, the semiconductor device 1 according to the present embodiment makes it possible to improve a manufacturing yield.

[0057] Next, a description is given of Modification examples 1 to 4 of the present disclosure. It is to be noted that components corresponding to those of the semiconductor device 1 according to the above-described embodiment are denoted with the same reference numerals, and descriptions thereof are omitted. <2. Modification Examples> (2-1. Modification Example 1)

[0058] Fig. 9 schematically illustrates respective configurations of an upper surface (A) and a cross section (B) of a semiconductor laser element 10A according to Modification example 1 of the present disclosure.

[0059] In the semiconductor laser element 10A of the present modification example, a dielectric film 15 is further provided between a part, of the upper surface 10S1 of the semiconductor laser element 10A, positioned outside the ridge part 11 sandwiched by the pair of trenches 12, and the dielectric film 13, and the extending part X1 has a stacked structure including the dielectric film 15, the dielectric film 13, and the upper electrode 117. Except for this point, the semiconductor laser element 10A has a configuration substantially similar to that of the semiconductor laser element 10 of the above-described embodiment.

[0060] The dielectric film 15 corresponds to a specific example of a "second dielectric film" according to one embodiment of the present disclosure. The dielectric film 15 includes, for example, silicon oxide (SiO2), as with the dielectric film 13. A thickness of the dielectric film 15 is, for example, greater than or equal to 100 nm and less than or equal to 600 nm.

[0061] As described above, in the semiconductor laser element 10A of the present modification example, the extending part X1 has the stacked structure including the dielectric film 15, the dielectric film 13, and the 117, to thereby gain a height of the extending part X1. This makes it possible to further prevent formation of the end surface coating film 14 on the two-dimensional code 20 caused by the spreading of the end surface coating film 14, as compared with the above-described embodiment. Therefore, the semiconductor laser element 10A of the present modification example makes it possible to further improve the manufacturing yield.

[0062] Further, in the semiconductor laser element 10A of the present modification example, the dielectric film 15 is further provided between the part, of the upper surface 10S1 of the semiconductor laser element 10A, positioned outside the ridge part 11 sandwiched by the pair of trenches 12, and the dielectric film 13. Thus, the part, of the upper surface 10S1 of the semiconductor laser element 10A, positioned outside the ridge part 11 becomes sufficiently higher than the upper surface of the ridge part 11, which makes it possible to suppress damage to the ridge part 11 that can be caused when laser bars are set by the jigs. Therefore, the semiconductor laser element 10A of the present modification example makes it possible to improve reliability. (2-2. Modification Example 2)

[0063] Fig. 10 schematically illustrates respective configurations of an upper surface (A) and a cross section (B) of a semiconductor laser element 10B according to Modification example 2 of the present disclosure.

[0064] In the above-described embodiment, the example has been described in which the extending part X1 is provided between the end surface (the resonator end surface Sa1) that is on a side closer to the two-dimensional code 20 and the two-dimensional code 20; however, this is non-limiting. In the semiconductor laser element 10B of the present modification example, extending parts X1 and X2 are respectively provided between the resonator end surface Sa1 and the two-dimensional code 20 and between the resonator end surface Sa2 and the two-dimensional code 20. Except for this point, the semiconductor laser element 10B has a configuration substantially similar to that of the semiconductor laser element 10 of the above-described embodiment.

[0065] The semiconductor laser element 10B of the present modification example having such a configuration also makes it possible to achieve effects similar to those of the above-described embodiment and Modification example 1. (2-3. Modification Example 3)

[0066] Fig. 11 schematically illustrates respective configurations of an upper surface (A) and a cross section (B) of a semiconductor laser element 10C according to Modification example 3 of the present disclosure.

[0067] In the above-described embodiment, the example has been described in which the two-dimensional code 20 is provided only in one of a pair of regions R1 and R2 (for example, only in the region R1) positioned outside the ridge part 11 sandwiched by the pair of trenches 12; however, this is non-limiting. In the semiconductor laser element 10C of the present modification example, two-dimensional codes 20A and 20B are respectively provided in the regions R1 and R2 positioned outside the ridge part 11. In addition, an extending part X1 is provided between the two-dimensional code 20A provided in the region R1 and the resonator end surface Sa1 that is on a side closer to the two-dimensional code 20A, and an extending part X3 is provided between the two-dimensional code 20B provided in the region R2 and the resonator end surface Sa1 that is on a side closer to the two-dimensional code 20B. Further, an extending part X2 may also be provided between the two-dimensional code 20A provided in the region R1 and the resonator end surface Sa2 that is on an opposite side to the resonator end surface Sa1 on the side closer to the two-dimensional code 20A. Except for those points, the semiconductor laser element 10C has a configuration substantially similar to that of the semiconductor laser element 10 of the above-described embodiment.

[0068] The semiconductor laser element 10C of the present modification example having such a configuration also makes it possible to achieve effects similar to those of the above-described embodiment and Modification example 1. (2-4. Modification Example 4)

[0069] Fig. 12 is a perspective diagram illustrating a configuration example of a semiconductor device 1A according to Modification example 4 of the present disclosure.

[0070] In the above-described embodiment, the example has been described in which the semiconductor laser element 10 is mounted on the submount 30; however, this is non-limiting. In the semiconductor device 1A of the present modification example, the semiconductor laser element 10 is mounted on a heat sink 70 instead of the submount 30. Except for this point, the semiconductor device 1A has a configuration substantially similar to that of the semiconductor device 1 of the above-described embodiment.

[0071] The heat sink 70 corresponds to a specific example of the "bonding object" according to one embodiment of the present disclosure. As with the submount 30, the heat sink 70 includes, for example, a block including, as surfaces thereof, the mounting surface Sb1, the bonding end surface Sb2, the non-bonding end surface Sb3, and the side surfaces Sb4 and Sb5, as illustrated in Fig. 12. In the block of the heat sink 70, the mounting surface Sb1 is provided with the coupling electrode Ec and the external electrode Eb. In the block of the heat sink 70, the bonding end surface Sb2 is provided with the bonding metal layer 32. The block of the heat sink 70 includes, for example, Cu, Fe, Al, Au, W, Mo, a composite material including any of these materials, or the like. Examples of such a composite material include Cu-W, Cu-Mo, and the like.

[0072] The semiconductor device 1A of the present modification example having such a configuration also makes it possible to achieve effects similar to those of the above-described embodiment.

[0073] Although the present disclosure has been described above with reference to the embodiment and Modification examples 1 to 4, the present disclosure is not limited to the embodiment and the like described above, and various modifications may be made. For example, any two or more of the respective configurations of the embodiment and Modification examples 1 to 4 described above may be appropriately combined with each other.

[0074] For example, the semiconductor device and the semiconductor laser element of the present disclosure do not necessarily have to include all of the components described in the embodiment and the like above, and conversely, may include any other layer. In one example, the semiconductor laser element 10 may further include, for example, a spacer layer adapted to adjust optical confinement in a stacking direction. In one example, the semiconductor laser element 10 may further include, for example, a stopper layer adapted to stop etching within the upper clad layer 115 in the process of forming the pair of trenches 12.

[0075] Furthermore, not all of the configurations and the operations described in the embodiment and the like above are necessarily essential as the configurations and the operations of the present disclosure. For example, among the components in the embodiment and the like described above, the components not recited in the independent claim representing the broadest concept of the present disclosure should be understood as optional components.

[0076] The terms used throughout this specification and the appended claims are to be interpreted as "non-limiting" terms. For example, the terms "include" or "be included" are to be interpreted as "not limited to the example described as being included". For example, the term "have" is to be interpreted as "not limited to the example described as having".

[0077] The terms in this specification are used merely for convenience of description, and include terms that are not used to limit the configurations and the operations. For example, the terms "right", "left", "up", "down", and the like merely indicate the directions in the drawing to which reference is made. Further, the terms "inner" and "outer" merely indicate a direction toward the center of the component of interest and a direction away from the center of the component of interest, respectively. This similarly applies to terms similar to the above-described terms, terms having meanings similar to those of the above-described terms, and the like.

[0078] It is to be noted that the effects described in this specification are mere examples and description thereof is non-limiting. Any other effect may also be achieved.

[0079] It is to be noted that the present disclosure may have any of the following configurations. According to the present technology having any of the following configurations, it is possible to improve a manufacturing yield. (1) A semiconductor device, including an end surface coated with a film, an upper surface disposed substantially orthogonally to the end surface, an electrode disposed substantially across the upper surface, an identifying mark disposed on the upper surface, and a protruding portion of the electrode which is disposed between the identifying mark and a plane substantially defined by the end surface, wherein the protruding portion has a thickness measured along an axis orthogonal to the upper surface which is greater than or equal to a thickness of the identifying mark measured along the axis. (2) The semiconductor device according to (1), wherein the identifying mark is a barcode, a letter, a number, a symbol, or a combination thereof. (3) The semiconductor device according to (1) or (2), wherein the identifying mark conveys information about electric properties of the semiconductor device, address information of the semiconductor device in a crystalline substrate, manufacturing information about the semiconductor device, or combinations thereof. (4) The semiconductor device according to (1) to (3), wherein the identifying mark is disposed on the upper surface closer to the end surface than to a surface longitudinally opposed to the end surface. (5) The semiconductor device according to (1) to (4), wherein the protruding portion of the upper surface has a dimension along a width axis parallel to a plane of the end surface and coplanar with the upper surface which is longer than a maximum dimension of the identifying mark on the width axis. (6) The semiconductor device according to (1) to (5), wherein the protruding portion of the upper surface further includes a first dielectric film and a second dielectric film. (7) The semiconductor device according to (6), wherein the first dielectric film is between 100 nm and 600 nm in thickness. (8) The semiconductor device according to (1) to (7), further including a second identifying mark. (9) The semiconductor device according to (8), further including a second raised portion of the upper surface disposed between the identifying mark and a surface longitudinally opposed to the end surface. (10) The semiconductor device according to (1) to (9), wherein the semiconductor device is mounted on a heat sink. (11) The semiconductor device according to (1) to (10), wherein the upper surface includes a ridge portion disposed between a first recessed trench portion and a second recessed trench portion. (12) The semiconductor device according to (1) to (11), wherein the identifying mark is formed by laser marking. (13) The semiconductor device according to (1) to (12), wherein the identifying mark is formed by photolithographic etching. (14) The semiconductor device according to (1) to (13), wherein a portion of the identifying mark protrudes from or is recessed from the upper surface. (15) The semiconductor device according to (1) to (14), wherein the identifying mark is a matrix code. (16) The semiconductor device according to (1) to (15), wherein the film is a multilayer reflective film or an antireflection film. (17) The semiconductor device according to (1) to (16), wherein the film includes a dielectric. (18) The semiconductor device according to (1) to (17), wherein a surface longitudinally opposed to the end surface is coated with a film. (19) A semiconductor device including: a semiconductor light-emitting element including a first surface, a second surface, and a pair of end surfaces, the first surface and the second surface being opposed to each other, the pair of end surfaces being opposed to each other and each having a normal line that intersects a normal line of the first surface; an electrode film provided on the first surface of the semiconductor light-emitting element; a protection object structure provided on the first surface of the semiconductor light-emitting element; and an extending part that is an extension of the electrode film between the protection object structure and one of the pair of end surfaces. (20) The semiconductor device according to (19), in which the semiconductor light-emitting element includes a semiconductor layer, the semiconductor layer including a first-conductivity-type layer, an active layer, and a second-conductivity-type layer, the second-conductivity-type layer being stacked on the first-conductivity-type layer via the active layer and having a ridge part, the ridge part extending in a direction in which the end surfaces are opposed to each other, and the electrode film is electrically coupled to the second-conductivity-type layer in the ridge part. (21) The semiconductor device according to (20), in which the semiconductor layer includes, as the pair of end surfaces, a pair of resonator end surfaces opposed to each other in an extending direction of the ridge part. (22) The semiconductor device according to (20) or (21), further including a first dielectric film, in which the first dielectric film is provided between the first surface of the semiconductor layer excluding the ridge part, and the electrode film. (23) The semiconductor device according to (22), in which the second-conductivity-type layer further includes a pair of trenches that allows the ridge part to be provided, and the first dielectric film extends on a part, of the second-conductivity-type layer, positioned outside the ridge part sandwiched by the trenches, as well as side surfaces and bottom surfaces of the trenches. (24) The semiconductor device according to (23), further including a second dielectric film, in which the second dielectric film is selectively provided on a part, of the second-conductivity-type layer, positioned outside the ridge part sandwiched by the trenches, and the extending part has a stacked structure including the electrode film and the second dielectric film. (25) The semiconductor device according to any one of (19) to (24), in which the protection object structure includes a two-dimensional code that identifies the semiconductor light-emitting element. (26) The semiconductor device according to any one of (19) to (25), in which a width of the extending part in an extending direction is wider than a width of the protection object structure in the extending direction. (27) The semiconductor device according to any one of (19) to (26), in which the extending part is provided at each of a part between the protection object structure and one of the pair of end surfaces, and a part between the protection object structure and another of the pair of end surfaces. (28) The semiconductor device according to any one of (20) to (27), in which the second-conductivity-type layer includes a first region and a second region with the ridge part interposed therebetween, and the protection object structure is provided in the first region or the second region, or in each of the first region and the second region. (29) The semiconductor device according to any one of (19) to (28), further including a bonding object having a bonding surface, in which the semiconductor light-emitting element is bonded to the bonding object to cause the second surface and the bonding surface are opposed to each other. (30) The semiconductor device according to (29), in which the bonding object includes a submount a heat sink.

[0080] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.Reference Numerals List

[0081] 1, 1A semiconductor device 10, 10A, 10B, 10C, 50 semiconductor laser element 11 ridge part 12 trench 13, 15 dielectric film 14, 54 end surface coating film 20, 20A, 20B, 60 two-dimensional code 30 submount 31 block 32 bonding metal layer 40 solder layer 70 heat sink 100, 500 laser bar 110 semiconductor stack section 111 substrate 112 buffer layer 113 lower clad layer 114 active layer 115 upper clad layer 116 contact layer 117 upper electrode 118 lower electrode 10S1 upper surface 10S2 lower surface Sa3, Sa4, Sb4, Sb5 side surface Eb external electrode Ec coupling electrode R1, R2 region Sa1, Sa2 resonator end surface Sb1 mounting surface Sb2 bonding end surface Sb3 non-bonding end surface X1, X2, X3 extending part

Claims

1. A semiconductor device, comprising: an end surface coated with a film; an upper surface disposed substantially orthogonally to the end surface; an electrode disposed substantially across the upper surface; an identifying mark disposed on the upper surface; and a protruding portion of the electrode which is disposed between the identifying mark and a plane substantially defined by the end surface, wherein the protruding portion has a thickness measured along an axis orthogonal to the upper surface which is greater than or equal to a thickness of the identifying mark measured along the axis.

2. The semiconductor device of claim 1, wherein the identifying mark is a barcode, a letter, a number, a symbol, or a combination thereof.

3. The semiconductor device of claim 1, wherein the identifying mark conveys information about electric properties of the semiconductor device, address information of the semiconductor device in a crystalline substrate, manufacturing information about the semiconductor device, or combinations thereof.

4. The semiconductor device of claim 1, wherein the identifying mark is disposed on the upper surface closer to the end surface than to a surface longitudinally opposed to the end surface.

5. The semiconductor device of claim 1, wherein the protruding portion of the upper surface has a dimension along a width axis parallel to a plane of the end surface and coplanar with the upper surface which is longer than a maximum dimension of the identifying mark on the width axis.

6. The semiconductor device of claim 1, wherein the protruding portion of the upper surface further includes a first dielectric film and a second dielectric film.

7. The semiconductor device of claim 6, wherein the first dielectric film is between 100 nm and 600 nm in thickness.

8. The semiconductor device of claim 1, further including a second identifying mark.

9. The semiconductor device of claim 8, further including a second raised portion of the upper surface disposed between the identifying mark and a surface longitudinally opposed to the end surface.

10. The semiconductor device of claim 1, wherein the semiconductor device is mounted on a heat sink.

11. The semiconductor device of claim 1, wherein the upper surface includes a ridge portion disposed between a first recessed trench portion and a second recessed trench portion.

12. The semiconductor device of claim 1, wherein the identifying mark is formed by laser marking.

13. The semiconductor device of claim 1, wherein the identifying mark is formed by photolithographic etching.

14. The semiconductor device of claim 1, wherein a portion of the identifying mark protrudes from or is recessed from the upper surface.

15. The semiconductor device of claim 1, wherein the identifying mark is a matrix code.

16. The semiconductor device of claim 1, wherein the film is a multilayer reflective film or an antireflection film.

17. The semiconductor device of claim 1, wherein the film includes a dielectric.

18. The semiconductor device of claim 1, wherein a surface longitudinally opposed to the end surface is coated with a film.

Images