JP7291537B2 - semiconductor light emitting device - Google Patents

Description

The present invention relates to a semiconductor light emitting device such as a light emitting diode (LED).

A flip-chip type semiconductor light-emitting device is known in which a semiconductor light-emitting element, in which a semiconductor layer including an active layer is laminated on a transparent substrate, is mounted on a mounting surface while being turned upside down (for example, Cited Document 1). In a flip-chip type semiconductor light-emitting device, both positive (p-electrode) and negative (n-electrode) electrodes are provided on the same plane side of the semiconductor light-emitting element. Further, when mounting a flip chip type semiconductor light emitting device, each electrode provided on the element side and each wiring provided on the mounting surface are joined via a conductive joining member such as AuSn, and then reflowed. The solder melts and electrical continuity is established.

Patent No. 5272287

In bonding the semiconductor light emitting element and the mounting surface as described above, the melted bonding material may flow out to areas other than the area where the electrode and the wiring are bonded, causing leaks and short circuits. In such a case, the characteristics as designed as a semiconductor light-emitting device cannot be obtained, and the problem is that the yield decreases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flip-chip type semiconductor light-emitting device which is free from leaks and shorts, has high quality, and has a high yield.

A semiconductor light emitting device of the present invention comprises: a first semiconductor layer of a first conductivity type; a first electrode formed in one region on an upper surface of the first semiconductor layer; an active layer formed in another region of the upper surface; a second semiconductor layer formed on the active layer and having a second conductivity type opposite to the first conductivity type; and a first protection made of an insulator having a first opening formed on the surface of the second electrode and exposing the surface of the second electrode. a film, a first joining member made of a conductor provided on the first electrode, a second joining member made of a conductor provided on the surface exposed by the first opening, and a substrate having one surface facing the first electrode and the second electrode; and a first opening formed on the surface of the substrate at a position facing the second electrode on the first surface of the substrate and spaced apart from the first wiring. A second wiring made of a conductor bonded to the second bonding member in a predetermined bonding region facing each other, and a second wiring formed on the surface of the second wiring and far from the first wiring in the bonding region. and a second protective film extending from the end in a direction away from the first wiring.

Further, the semiconductor light emitting device of the present invention includes: a first semiconductor layer of a first conductivity type; a first electrode formed in one region on an upper surface of the first semiconductor layer; an active layer formed in another region of the upper surface of the layer; a second semiconductor layer of a second conductivity type opposite to the first conductivity type formed on the active layer; A first insulator comprising a second electrode formed on a second semiconductor layer and an insulator having a first opening formed on the surface of the second electrode and exposing the surface of the second electrode a protective film, a first joining member made of a conductor provided on the first electrode, and a second joining member made of a conductor provided on the surface exposed by the first opening. , a substrate having one surface facing the first electrode and the second electrode, and the first joining member formed at a position facing the first electrode on the one surface of the substrate and a first opening formed on the first surface of the substrate at a position facing the second electrode and spaced apart from the first wiring. a second wiring made of a conductor bonded to the second bonding member in a predetermined bonding region facing the portion; and a second protective film made of an insulator that is exposed to the surface of the second wiring, and the first opening is exposed from the second protective film on the surface of the second wiring when viewed from above. Alternatively, a region of the surface of the second wiring that is exposed from the second protective film includes the first opening.

1 is a top view of a semiconductor light emitting device according to Example 1 of the present invention; FIG. 1 is a top view of a semiconductor light emitting device of Example 1. FIG. FIG. 2 is a partially enlarged view of the top view of FIG. 1; 2 is a cross-sectional view of the semiconductor light emitting device of FIG. 1; FIG. 2 is a top view of the submount of the semiconductor light emitting device of Example 1. FIG. 2 is a cross-sectional view showing a state in which a semiconductor light emitting element and a submount are aligned before bonding the semiconductor light emitting device of FIG. 1; FIG. FIG. 10 is a cross-sectional view of a semiconductor light emitting device of Example 2;

Examples of the present invention are described in detail below. In the following description and accompanying drawings, substantially the same or equivalent parts are denoted by the same reference numerals. Part of the top view is hatched for explanation.

A configuration of a semiconductor light emitting device 10 according to Example 1 of the present invention will be described with reference to FIGS. 1 to 4. FIG. FIG. 1 is a top view of a semiconductor light emitting device 10. FIG. As shown in FIG. 1, a semiconductor light emitting device 10 is constructed by mounting a semiconductor light emitting element (optical semiconductor chip) 30 on a submount 11 having a mounting surface. In FIG. 1, only the outer shape of the semiconductor light emitting device 30 is indicated by broken lines, and other parts are omitted.

The submount 11 is configured by forming electrodes and the like on a submount substrate 12 . The submount substrate 12 is a plate-like mounting substrate having a surface 1 as a mounting surface for the light emitting element. As shown in FIG. 1, the submount substrate 12 has, for example, a rectangular shape when viewed from above. The submount substrate 12 is, for example, an AlN ceramic substrate, and other substrates such as alumina are used.

The n-wiring electrode 13 as the first wiring is an electrode pattern formed on the mounting surface of the submount substrate 12 . The n-wiring electrode 13 is formed in a region along one side of the submount substrate 12 on the mounting surface of the submount substrate 12 . The n-wiring electrode 13 is made of a conductor such as a metal such as Ti, Pt, Au or Pd.

A p-wiring electrode 15 as a second wiring is an electrode pattern formed on the mounting surface of the submount substrate 12 . The p-wiring electrode 15 is formed electrically separated from the n-wiring electrode 13 .

The p-wiring electrode 15 is composed of a base portion 15A and an extension portion 15B. The base portion 15A is a portion formed in a region along the side opposite to the side on which the n-wiring electrode 13 is formed. The extension portion 15B is a plurality of stripe-shaped portions extending from the base portion 15A toward the n-wiring electrode 13. As shown in FIG. In this way, the p-wiring electrode 15 has a comb tooth shape consisting of the base portion 15A and the extension portion 15B.

Hereinafter, the direction along the long side of the stripe shape of the extension portion 15B is referred to as the X direction. The p-wiring electrode 15 is made of a conductor such as a metal such as Ti, Pt, Au or Pd.

A p-wiring protective film 17 as a second protective film is provided on the p-wiring electrode 15 . As shown in FIG. 1, the p-wiring protective film 17 is formed at the end of the p-wiring electrode 15 near the base 15A of the extension 15B. Further, the p-wiring protective film 17 may extend up to the region of the base portion 15A as shown in FIG.

The p-wiring protective film 17 is a metal film such as Cr, W, Pt, or the like. Further, for example, the p-wiring protective film 17 may be a metal oxide film such as a chromium oxide film, or may be an insulating film such as an SiO ₂ film. Furthermore, the p-wiring protective film 17 may be formed by forming an insulating film such as SiO ₂ on a metal film such as Cr.

A p-wiring protective film 19 as a third protective film is provided on the p-wiring electrode 15 . As shown in FIG. 1, the p-wiring protective film 19 is formed at the distal end portion of the extending portion 15B from the base portion 15A, that is, at the tip of the extending portion 15B.

The p-wiring electrode 15 is exposed between the p-wiring protective film 17 formed on the proximal end of the extending portion 15B from the base 15A and the p-wiring protective film 19 formed on the distal end. ing. For example, the p-wiring protective film 19 is made of a metal film such as Cr, an insulating film such as a metal oxide film, or a combination of a metal film and an insulating film.

The n-wiring protective film 21 is provided on the n-wiring electrode 13 . The n-wiring protective film 21 is formed along one side of the submount substrate 12 on which the n-wiring electrode 13 is formed. Like the p-wiring protective film 17 and the p-wiring protective film 19, the n-wiring protective film 21 is made of a metal film such as Cr, an insulating film such as a metal oxide film, or a combination of a metal film and an insulating film. Hereinafter, each of the stripe-shaped portion of the p-wiring electrode 15 and the portion formed of the p-wiring protective film 19 will be referred to as a stripe portion 23 .

FIG. 2 is a top view of the semiconductor light emitting element 30 of the semiconductor light emitting device 10 of Example 1, looking at the surface facing the submount 11 of FIG. 1 during bonding. The growth substrate 31 has a rectangular shape when viewed from above. The growth substrate 31 is, for example, an AlN substrate, which is a substrate that transmits visible light. Substrates such as sapphire and SiC are also used. An n-type semiconductor layer 33 as a first semiconductor layer is formed on the growth substrate 31 so as to cover the top surface of the growth substrate 31 . An n-electrode 35 as a first electrode is formed on the n-type semiconductor layer 33 . The n-electrode 35 is formed on the n-type semiconductor layer 33 in the vicinity of one side of the growth substrate 31 along the one side when viewed from above. In other words, the n-electrode 35 as the first electrode is formed in one region along the vicinity of one side on the n-type semiconductor layer 33 .

A plurality of light emitting units 36 are formed on the n-type semiconductor layer 33 . A p-electrode 37 is formed on the upper surface of each of the light emitting portions 36 . A p-electrode 37 as a second electrode is arranged above the n-type semiconductor layer 33 . Each of p-electrodes 37 has a stripe shape. Each of the p-electrodes 37 has a shape corresponding to the stripe portion 23 formed on the submount substrate 12 shown in FIG. 1 at the time of bonding.

The p-electrode 37 is formed on a p-type semiconductor layer (not shown) having the same shape. The p-type semiconductor layer is formed on a similarly shaped active layer (not shown) formed on the n-type semiconductor layer 33 .

A p-electrode protective film 39 as a first protective film is formed to cover the outer peripheral portion of the p-electrode 37 . The p-electrode protective film 39 has an opening 39OP. In other words, the p-electrode 37 is exposed from the p-electrode protective film 39 in the region of the opening 39OP of the p-electrode protective film 39 . The p-electrode protective film 39 is made of an insulator such as _SiO2 . For example, the p-electrode protective film 39 may be another metal oxide film. The p-electrode protective film 39 has optical transparency with respect to light emitted from the semiconductor light-emitting device 10 .

The n-electrode protective film 41 is provided on at least part of the outer periphery of the n-electrode 35 and is made of an insulator such as SiO ₂ . As shown in FIG. 2, the n-electrode protective film 41 is formed on the side adjacent to the p-electrode 37 and the side opposite thereto in the outer peripheral portion of the n-electrode 35 . The n-electrode protective film 41 has optical transparency with respect to light emitted from the semiconductor light-emitting device 10 .

FIG. 3 is an enlarged view of a portion B surrounded by a dashed line in FIG. The portion B corresponds to the portion B surrounded by the dashed line in FIG. FIG. 3 shows the positional relationship between the p-electrode protective film 39 and the stripe portion 23 when the semiconductor light emitting device 30 of FIG. 2 is mounted on the submount 11 when viewed from above. In FIG. 3, only the p-electrode protective film 39 of the semiconductor light emitting device 30 is shown, and other parts are omitted.

As shown in FIG. 3, the p-electrode protective film 39 and the p-wiring protective film 17 have regions in the vicinity of the proximal end portion of the base portion 15A of the stripe portion 23 that overlap each other when viewed from above. In addition, the p-electrode protective film 39 and the p-wiring protective film 19 have regions near the distal end of the base portion 15A of the stripe portion 23 that overlap each other when viewed from above. Both the p-wiring protective film 17 and the p-wiring protective film 19 overlap the p-electrode protective film 39 over the entire stripe width direction (short side direction) of the stripe portion 23 .

Furthermore, as shown in FIG. 3 , the p-wiring protective film 17 and the p-wiring protective film 19 extend to the inside of the opening 39 OP of the p-electrode protective film 39 . That is, the p-wiring protective film 17 and the p-wiring protective film 19 extend beyond the region overlapping the p-electrode protective film 39 to the inside of the opening 39OP.

A region where the p-wiring electrode 15 is exposed from the p-wiring protective film 17 and the p-wiring protective film 19 is JA1. JA2 is the area inside the opening 39OP. As shown in FIG. 3, the area of the area JA2 is larger than the area of the area JA1.

Also, the length of the long side of the area JA1 is L1, and the length of the long side of the area JA2 is L2. As shown in FIG. 3, the length of L2 is greater than the length of L1. Also, in FIG. 3, the area JA2 includes the area JA1.

FIG. 4 is a cross-sectional view of the semiconductor light emitting device 10 of FIG. 1 taken along line 4-4 in FIG. As described above, the semiconductor light emitting device 10 has the semiconductor light emitting element 30 shown in FIG. 2 turned upside down and bonded onto the submount 11 . FIG. 4 shows a cross-sectional configuration in which the submount substrate 12 is the bottom layer and the growth substrate 33 is the top layer.

As described above, the n-type semiconductor layer 33 is formed on the growth substrate 31 of the semiconductor light emitting device 30 . As shown in FIG. 4, the n-electrode 35 as a first electrode is formed in one region on the n-type semiconductor layer 33 . The active layer 43 is formed in another region on the n-type semiconductor layer 33 . A p-type semiconductor layer 45 is formed on the active layer 43 . A p-electrode 37 as a second electrode is formed on the p-type semiconductor layer 45 . Light from the active layer 43 is emitted from the n-type semiconductor layer 33 side. Therefore, the main surface of the growth substrate 31 facing the surface on which the n-type semiconductor layer 33 is formed serves as the light exit surface.

The wavelength of light emitted from the active layer 43 depends on the materials and compositions of the n-type semiconductor layer 33 , the active layer 43 and the p-type semiconductor layer 45 . For example, the wavelength of light emitted from the active layer 43 may be a wavelength in the deep ultraviolet region or a wavelength in the infrared region.

As shown in FIG. 4, the n-electrode 35 and the p-electrode 37 are formed at different distances from the growth substrate 31 . In other words, there is a step between the n-electrode 35 and the p-electrode 37 .

A p-electrode protective film 39 as a first protective film is formed on the outer periphery of the surface of the p-electrode 37 and has an opening 39OP as a first opening. The first protective film 39 exposes the p-electrode 37 as the second electrode in the opening 39OP.

In FIG. 4, the p-electrode protective film 39 continuously covers the side surfaces of the p-type semiconductor layer 45, the active layer 43, and the n-type semiconductor layer 33 from the surface of the p-electrode 37, but is not limited to this. . The p-electrode protective film 39 may be formed on the surface of the p-electrode 37 .

The n-electrode protective film 41 is formed on the outer peripheral portion adjacent to the p-electrode 37 of the n-electrode 35 and the outer peripheral portion opposite thereto.

The n-wiring electrode 13 as the first wiring is formed on the submount substrate 12 at a position facing the n-electrode 35 .

The p-wiring electrode 15 as a second wiring is formed at a position that is spaced apart from the n-wiring electrode 13 and faces the p-electrode 37 .

The first bonding member 47 is a layer made of a conductive bonding material formed on the n-wiring electrode 13 . The first joining member 47 is formed between the surface of the n-electrode 35 exposed from the n-electrode protective film 41 and the surface of the n-wiring electrode 13 facing thereto. The first joining member 47 joins the surface of the n-electrode 35 and the surface of the n-wiring electrode 13 . In other words, the surface of the n-electrode 35 and the surface of the n-wiring electrode 13 are joined via the first joining member 47 .

The first joining member 47 is made of a material having a melting point lower than that of the n-electrode 35 and the n-wiring electrode 13 . For example, low melting point solder or eutectic solder can be used for the first joining member 47 . For example, AuSn can be used for the first joint member 47 .

The second bonding member 49 is a layer made of a conductive bonding material formed on the p-wiring electrode 15 . The second bonding member 49 is formed between the surface of the p-electrode 37 exposed from the opening 39OP of the first protective film 39 and the surface of the p-wiring electrode 15 facing it. The second joining member 49 joins the surface of the p-electrode 37 and the surface of the p-wiring electrode 15 . In other words, the p-wiring electrode 15 is joined to the second joint member 49 in the joint region J1, which is a predetermined joint region facing the opening 39OP. Also, the surface of the p-electrode 37 and the surface of the p-wiring electrode 15 are joined via a second joining member 49 .

The second joint member 49 is made of a material having a melting point lower than that of the p-electrode 37 and p-wiring electrode 15 . For example, low melting point solder or eutectic solder, such as AuSn, can be used for the second bonding member 49 .

In addition, the second bonding member 49 has a high contact angle with the p-electrode protective film 39 when melted, and has low wettability (affinity). For example, the p-electrode protective film 39 has a contact angle of greater than 90° with the melted second bonding member 49 .

As described above, the p-wiring protective film 17 as the second protective film is formed on the surface of the p-wiring electrode 15 . The p-wiring protective film 17 extends in a direction away from the n-wiring electrode 13 from the end of the junction region JA1 far from the n-wiring electrode 13 .

A portion where the p-wiring electrode 15 is exposed may exist between the end of the junction region JA1 far from the n-wiring electrode 13 and the p-wiring protective film 17 . That is, the second bonding member 49 may be formed with a space above the p-wiring electrode 15 between the p-wiring protective film 17 and the p-wiring protective film 17 .

The p-wiring protective film 17 as a second protective film has an overlapping region OL that overlaps with the first protective film 39 in the direction perpendicular to the substrate surface of the submount substrate 12 . In addition, the p-wiring protective film 17 has a region EX extending from the end surface of the growth substrate 31 toward the outside of the semiconductor light-emitting device 10 .

The p-wiring protective film 17 is made of a material having a melting point higher than that of the second bonding member 49 . The surface of the p-wiring protective film 17 has a high contact angle and low wettability (affinity) with the second bonding member 49 when the second bonding member 49 is melted. For example, the contact angle between the surface of the p-wiring protective film 17 and the second bonding member 49 is greater than 90°.

A p-wiring protective film 19 as a third protective film extends from the end of the surface of the p-wiring electrode 15 near the n-wiring electrode 13 . The p-wiring protective film 19 is made of a material having a melting point higher than that of the second bonding member 49 .

A portion where the p-wiring electrode 15 is exposed may exist between the end of the junction region JA1 far from the n-wiring electrode 13 and the p-wiring protective film 19 . That is, the second bonding member 49 may be formed with a space between it and the p-wiring protective film 19 .

As shown in FIG. 3, the p-wiring protective film 17 and the p-wiring protective film 19 extend to the inside of the opening 39OP when viewed from above. Therefore, in the X direction in FIG. 4, that is, the direction along the long side of the stripe shape of the p-wiring electrode 15, the distance L1 between the p-wiring protective film 17 and the p-wiring protective film 19 is less than the length L2 of the opening 39OP. is also small.

The n-wiring protective film 21 is provided on the n-wiring electrode 13 . The n-wiring protective film 21 extends from the outer peripheral portion of the submount substrate 12 over the n-wiring electrode 13 toward the first bonding member 47 . The n-wiring protective film 21 is made of a material having a melting point higher than that of the first bonding member 47 . For example, the n-wiring protective film 21 can reflect light emitted from the active layer 43 toward the emission surface by using a metal film such as Cr having light reflectance.

The semiconductor light emitting device 10 is manufactured, for example, as follows. FIG. 5 is a top view showing a state before bonding of the submount 11 used for manufacturing the semiconductor light emitting device 10. FIG. As shown in FIG. 5, the first bonding member 47 is patterned by sputtering or the like and arranged in a region on the n-wiring electrode 13 inside the outer periphery of the n-wiring electrode 13 . The second bonding member 49 is arranged on the surface of the p-wiring electrode 15 of the stripe portion 23 by patterning in a region inside the outer periphery of the portion where the p-wiring electrode 15 is exposed.

For example, in the state of FIG. 5, the second bonding member 49 is arranged so as to occupy 50% or less of the surface area of the p-electrode 37 exposed from the p-electrode protective film 39 through the opening 39OP. there is That is, in the state of FIG. 5, the area of the second bonding member 49 viewed from above is 50% or less of the area of the surface where the p-electrode 37 of the semiconductor light emitting element 30 to be bonded is exposed from the opening 39OP. is. Also, the second joint member 49 is arranged so as to have an area smaller than that of the joint area JA1.

First, the semiconductor light emitting device 30 as shown in FIG. 2 is picked up from a supply tray and set on a flip chip bonder. Also, the submount 11 as shown in FIG. 5 is similarly picked up from the supply tray and set. Alignment processing is performed by camera recognition so that the respective alignment marks match.

FIG. 6 is a cross-sectional view showing a cross section of the semiconductor light emitting element 30 and the submount 11 after alignment processing. As shown in FIG. 6, the n-electrode 35 and the first bonding member 47 face each other, and the p-electrode 37 and the second bonding member 49 face each other. Also, the growth substrate 31 and the submount substrate 12 are aligned in parallel.

As described above, the n-electrode 35 and the p-electrode 37 have different distances from the growth substrate 31 . In a state in which the growth substrate 31 and the submount substrate 12 are aligned in parallel, the distance between the p wiring electrode 15 and the p wiring electrode 15 is greater than the distance between the n wiring electrode 13 and the n electrode 35 (h1 in FIG. 6). The distance (h2 in FIG. 6) to the p-electrode 37 is smaller.

Further, as shown in FIG. 6, the first bonding member 47 and the second bonding member 49 before bonding are formed with the same layer thickness, and the height from the substrate surface of the submount substrate 12 is the same. (h2).

In addition, as described above, the second bonding member 49 occupies 50% or less of the surface area of the p-electrode 37 exposed from the p-electrode protective film 39 through the opening 39OP. Since it is arranged so as to have an area smaller than that of the region JA1, there are p regions between the second bonding member 49 and the p-wiring protective film 17 and between the second bonding member 49 and the p-wiring protective film 19. There is a portion where the surface of the wiring electrode 15 is exposed.

After the alignment process, the semiconductor light emitting element 30 and the submount substrate 12 are heated while the load is applied, and the first bonding member 47 and the second bonding member 49 are melted for a predetermined time. In order to prevent oxidation of the first bonding member 47 and the second bonding member 49, for example, nitrogen purge is performed during the heat treatment to keep oxygen in the bonding processing chamber as low as possible.

In the step of heating with the load applied (pressure/heat bonding step), the first bonding member 47 is bonded to the n-electrode 35 while taking in the material on the surface of the n-electrode 35 . On the other hand, regarding the second joint member 49, as described above, the distance between the p-wiring electrode 15 and the p-electrode 37 (h2 in FIG. 6) is equal to the distance between the n-wiring electrode 13 and the n-electrode 35 (h2 in FIG. 6). Since it is smaller than h1), a load is more likely to be applied to the second bonding member 49 than to the first bonding member 47 in the pressure/heat bonding process.

Therefore, the melted second bonding member 49 spreads due to affinity with the surfaces of the p-wiring electrode 15 and the p-electrode 37, and spreads due to being crushed by the load. and the p-electrode 37 . In addition, the second bonding member 49 changes its composition while taking in the material of the electrode such as Au in the pressure/heat bonding process, and spreads while gradually decreasing its fluidity.

More specifically, a portion (space) where the surface of the p-wiring electrode 15 is exposed exists between the second bonding member 49 and the p-wiring protective film 17 and the p-wiring protective film 19 before bonding. (Fig. 6). The second bonding member 49 wets and spreads the surface (that is, the space portion) of the p wiring electrode 15 while taking in the material (for example, Au) of the p wiring electrode 15, and has affinity with the melted second bonding member 49. is blocked by the p-wiring protective film 17 and the p-wiring protective film 19 having a low . The second joining member 49 may take in the material of the p-wiring electrode 15 to reduce its fluidity and stop spreading.

Further, the width (L2) of the exposed surface of the p-electrode 37 is larger than the width (L1) of the exposed surface of the p-wiring electrode 15 in the X direction (FIG. 6). Therefore, the second bonding member 49 has a larger space when extending over the surface of the p-electrode 37 . The second bonding member 49 expands the space on the surface of the p-electrode 37 while taking in the material (for example, Au) of the p-electrode 37 . Since the space is large, the fluidity is more likely to decrease and the fluid stops within the opening 39OP. Therefore, it is difficult to flow out of the opening 39OP.

After the pressure/heat bonding process described above, the semiconductor light emitting device 10 is completed through a cooling process.

In the manufacturing process described above, the second bonding member 49 spreads the surface of the p-electrode 37 in the bonding region JA2 larger than the bonding region JA1 while taking in the material of the p-electrode 37, thereby completing the semiconductor light-emitting device 10. Then, the second joint member 49 has a trapezoidal cross-sectional shape (FIG. 4). As shown in FIG. 4, if the side of the cross section of the second bonding member 49 that is bonded to the p-electrode 37 is the upper base, and the side that is bonded to the p-wiring electrode 15 is the lower base, then the upper base is The base is shorter than the base. In other words, the cross section of the second joint member 49 has a reverse tapered shape.

Also, the composition changes as it approaches the upper base of the trapezoid, that is, the p-electrode 37 . In particular, the material component of the p-electrode 37 increases at both end portions of the upper base. For example, when the second bonding member 49 is AuSn and the p-electrode 37 is an Au electrode, the Au concentration in the composition of the second bonding member 49 increases as the location corresponding to both end portions of the upper base of the trapezoid is approached. becomes higher.

In addition to the configuration having the overlapping region OL (FIG. 4) and the region EX (FIG. 4) where the p-wiring protective film 17 extends, the second joining member 49 in the state before joining is used to protect the p-electrode. By disposing so as to occupy 50% or less of the surface area of the p-electrode 37 exposed from the film 39 through the opening 39OP (FIG. 5), the second bonding member 49 flows out of the bonding region. can be prevented more reliably.

In addition, in the state before bonding, the second bonding member 49 is arranged so as to occupy 50% or less of the surface area of the p-electrode 37 exposed from the p-electrode protective film 39 through the opening 39OP. has been described (FIG. 5), but it is not limited to this. For example, when the second bonding member 49 is arranged to occupy 50% or more of the surface area of the p-electrode 37 exposed through the p-electrode protective film 39 or the opening 39OP, that is, the second bonding Even if the amount of the member 49 is increased, the second bonding member 49 can be blocked by the p-wiring protective film 17 and the p-wiring protective film 19 .

For example, the overlapping region OL (FIG. 4) and the region EX (FIG. 4) where the p-wiring protective film 17 extends block the melted second bonding member 49 to prevent it from flowing out of the bonding region. contribute to

Even if the first bonding member 47 and the second bonding member 49 before bonding are formed to have the same film thickness, outflow can be prevented. Therefore, the steps of forming the first joint member 47 and the second joint member 49 can be performed at once, and the manufacturing cost and time can be reduced. Further, by forming the first joint member 47 and the second joint member 49 with the same film thickness and the same height, it is possible to improve the alignment accuracy.

As described above, the semiconductor light-emitting device 10 of this embodiment is a semiconductor light-emitting element 30 having the n-electrode 35 formed on the n-type semiconductor layer 33 and the p-electrode 37 formed on the p-type semiconductor layer 45. and a submount substrate 12 having an n-wiring electrode 13 and a p-wiring electrode 15 formed on one surface. The n-electrode 35 and the n-wiring electrode 13 , and the p-electrode 37 and the p-wiring electrode 15 face each other and are joined via a first joining member 47 and a second joining member 49 . On the surface of the p-wiring electrode 15, a second protective film 17 extending in a direction away from the n-wiring electrode 13 from the end far from the n-wiring electrode 13 of the bonding region JA1 of the surface with the second bonding member 49 is formed. formed.

With such a configuration, even after the step of melting the first bonding member 47 and the second bonding member 49 and applying a load during bonding, the region on the surface of the p wiring electrode 15 that is not necessary for bonding can be removed. Since the second joint member 49 is not formed up to this point, it is possible to reliably prevent the occurrence of leaks and short circuits.

Therefore, desired emitted light from the active layer can be obtained. In addition, a sufficient bonding strength of the second bonding member 49 can be obtained, and a good bonding state can be obtained in terms of heat conduction and electrical resistance.

Therefore, according to the semiconductor light emitting device 10 of the present embodiment, it is possible to provide a flip-chip type semiconductor light emitting device with high quality and high yield without leakage or short circuit.

FIG. 7 is a cross-sectional view showing the configuration of a semiconductor light emitting device 50 according to Example 2 of the present invention. As in FIG. 4, FIG. 7 shows a cross section along the long side of the stripe of the p-wiring electrode 15 (the X direction in the figure).

A semiconductor light-emitting device 50 includes a p-wiring protective film 17 as a second protective film, a p-wiring protective film 19 as a third protective film, a p-wiring protective film 51 instead of the second bonding member 49, and a p-wiring protective film. The semiconductor light emitting device 10 differs from the semiconductor light emitting device 10 of Example 1 in that it has a film 53 and a second bonding member 55, and is otherwise configured in the same manner as the semiconductor light emitting device 10 of Example 1. FIG.

As shown in FIG. 7, the p-wiring protective film 51 extends from the position farther from the n-wiring electrode 13 in the X direction than the end of the opening 39OP of the p-electrode protective film 39 farther from the n-electrode 35 than the n-wiring electrode 13. extends away from the

The p-wiring protective film 53 extends toward the n-wiring electrode 13 from a position closer to the n-wiring electrode 13 in the X direction than the end portion of the opening 39 OP near the n-electrode 35 .

With such a configuration, the width L3 of the portion where the surface of the p-wiring electrode 15 is exposed from the p-wiring protective films 51 and 53 is larger than the width L2 of the opening 39OP in the X direction.

The second bonding member 55 is bonded to the surface of the p-wiring electrode 15 using the portion JA3 where the surface of the p-wiring electrode 15 is exposed from the p-wiring protective film 51 and the p-wiring protective film 53 as a bonding region. Also, the second bonding member 55 is bonded to the surface of the p-electrode 37 at the opening 39OP. That is, area JA3 includes area JA2. Moreover, as described above, the width L3 is larger than the width L2, and the cross section of the second joint member 55 has a tapered shape.

As with the semiconductor light emitting device 10, the semiconductor light emitting device 50 is manufactured through a pressure/heat bonding step. In the pressure/heat bonding step, the melted second bonding member 55 wets and spreads the surface of the p-wiring electrode 15 and the surface of the p-electrode 37 while taking in the electrode material such as Au. It is blocked by the wiring protection film 53 .

As shown in FIG. 7, the p-electrode protective film 39 and the p-line protective film 51 have an overlapping region OL when viewed from above. In addition, the p-wiring protective film 51 extends in the EX direction from the end far from the n-wiring electrode 13 of the junction region JA3. The overlapping region and the extending region of the p-wiring protective film 51 can block the melted second bonding member 55 .

Therefore, according to the semiconductor light emitting device 50 of the present embodiment, it is possible to prevent the joining member from reaching the region related to leakage and short circuit, and it is possible to provide a high quality and high yield semiconductor light emitting device.

The configurations in the above-described embodiments and manufacturing methods are merely examples, and can be changed as appropriate according to the application.

10, 50 semiconductor light emitting device 11 submount 12 submount substrate 13 n wiring electrode 15 p wiring electrode 17, 51 p wiring protective film 19, 53 p wiring protective film 21 n wiring protective film 23 stripe section 30 semiconductor light emitting device 31 growth substrate 33 first semiconductor layer (n-type semiconductor layer)
35 first electrode (n-electrode)
37 second electrode (p electrode)
39 first protective film (p-electrode protective film)
39OP first opening (opening)
40 light-emitting portion 41 n-electrode protective film 43 active layer 45 second semiconductor layer (p-type semiconductor layer)
47 first joint member 49, 55 second joint member

Claims (10)

a first semiconductor layer of a first conductivity type;
a first electrode formed in one region of the upper surface of the first semiconductor layer;
an active layer formed in another region of the top surface of the first semiconductor layer;
a second semiconductor layer of a second conductivity type opposite to the first conductivity type formed on the active layer;
a second electrode formed on the second semiconductor layer;
a first protective film made of an insulator formed on the surface of the second electrode and having a first opening exposing the surface of the second electrode;
a first joint member made of a conductor provided on the first electrode ;
a second joining member made of a conductor provided on the surface exposed by the first opening;
a substrate having one surface facing the first electrode and the second electrode;
a first wiring made of a conductor formed at a position facing the first electrode on the first surface of the substrate and bonded to the first bonding member;
In at least a part of a predetermined bonding region formed at a position facing the second electrode on the first surface of the substrate and spaced from the first wiring and facing the first opening on the surface a second wiring made of a conductor joined to the second joint member;
The first wiring formed on the surface of the second wiring and extending in a direction away from the first wiring from an end portion of the bonding region far from the first wiring and extending in a direction perpendicular to the substrate. a second protective film having a region overlapping the protective film;
formed on the surface of the second wiring and extending from an end portion of the bonding region near the first wiring toward an end portion of the second wiring near the first wiring; a third protective film having a region overlapping the first protective film in a vertical direction;
the second protective film extends on the second wiring to the inside of the first opening when viewed in a direction perpendicular to the substrate;
the third protective film extends on the second wiring to the inside of the first opening when viewed in a direction perpendicular to the substrate;
the area of the surface of the second electrode exposed by the first opening is larger than the area of the junction region of the second wiring;
The first protective film, the second protective film, and the third protective film each have an affinity with the second bonding member when the second bonding member melts. and a semiconductor light emitting device which is lower than the second wiring . 2. The second joint member according to claim 1 , wherein the second joint member has a trapezoidal cross-sectional shape, and the lower base in contact with the second wiring is shorter than the upper base in contact with the second electrode. semiconductor light emitting device. 3. The semiconductor light emitting device according to claim 1 , wherein the distance between said second electrode and said second wiring is smaller than the distance between said first electrode and said first wiring. 4. The semiconductor light-emitting device according to claim 1, wherein the first opening includes the junction region on the surface of the second wiring when viewed from above. a first semiconductor layer of a first conductivity type;
a first electrode formed in one region of the upper surface of the first semiconductor layer;
an active layer formed in another region of the top surface of the first semiconductor layer;
a second semiconductor layer of a second conductivity type opposite to the first conductivity type formed on the active layer;
a second electrode formed on the second semiconductor layer;
a first protective film made of an insulator formed on the surface of the second electrode and having a first opening exposing the surface of the second electrode;
a first joint member made of a conductor provided on the first electrode ;
a second joining member made of a conductor provided on the surface exposed by the first opening;
a substrate having one surface facing the first electrode and the second electrode;
a first wiring made of a conductor formed at a position facing the first electrode on the first surface of the substrate and bonded to the first bonding member;
In at least a part of a predetermined bonding region formed at a position facing the second electrode on the first surface of the substrate and spaced from the first wiring and facing the first opening on the surface a second wiring made of a conductor joined to the second joint member;
The first wiring formed on the surface of the second wiring and extending in a direction away from the first wiring from an end portion of the bonding region far from the first wiring and extending in a direction perpendicular to the substrate. a second protective film having a region overlapping the protective film;
formed on the surface of the second wiring and extending from an end portion of the bonding region near the first wiring toward an end portion of the second wiring near the first wiring; a third protective film having a region overlapping the first protective film in a vertical direction ;
the first protective film extends over a region of the surface of the second electrode that overlaps with the second protective film in a direction perpendicular to the substrate to a region that overlaps with the junction region;
the first protective film extends over a region of the surface of the second electrode that overlaps with the third protective film in a direction perpendicular to the substrate to a region that overlaps with the junction region;
the area of the bonding region of the second wiring is larger than the area of the surface of the second electrode exposed by the first opening;
The first protective film, the second protective film, and the third protective film each have an affinity with the second bonding member when the second bonding member melts. and a semiconductor light emitting device which is lower than the wiring . 6. The semiconductor according to claim 5, wherein the second joining member has a trapezoidal cross-sectional shape, wherein the lower base in contact with the second wiring is longer than the upper base in contact with the second electrode. Luminescent device. 7. The semiconductor light-emitting device according to claim 5, wherein the junction region includes the first opening when viewed from above. The second electrode is formed in a stripe shape,
8. The semiconductor light emitting device according to claim 1, wherein said second wiring includes a plurality of striped portions corresponding to said second electrodes. 9. The semiconductor light emitting device according to claim 1, wherein said second protective film and said third protective film are made of a material having a melting point higher than that of said second bonding member. . 10. The second protective film and the third protective film are a metal film, an insulating film containing a metal oxide film, or an insulating film formed on a metal film. The semiconductor light emitting device according to any one of .

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