TW201724581A - Light emitting element, light emitting element package and light emitting element manufacturing method providing a light emitting element high in quality and miniaturized and thinned - Google Patents

Abstract

This invention provides a light emitting element and the like which are high in quality and miniaturized and thinned. The light emitting element (1) includes a light emitting element chip (2) and a protective resin (3). The light emitting element chip (2) includes a substrate (2a) and a light emitting portion arranged on the substrate (2a). The protective resin (3) covers a side surface of the light emitting portion (2b) including a boundary portion between the substrate (2a) and the light emitting portion (2b) and also covers a part of the side face of the substrate (2a) containing the boundary portion.

Description

Light-emitting element, light-emitting element package, and method of manufacturing the same

The present invention relates to a light-emitting element of a light-emitting element wafer provided in a photosensor such as an electronic device such as a copying machine, a facsimile machine, or a printer, a light-emitting element package in which a light-emitting element is sealed by a resin, and a light-emitting element. method.

Conventionally, an optical sensor such as a copier or a printer has used a photosensor that detects the presence or absence of an object in a non-contact manner. As an example of the photo sensor, there is a photo interrupter. The photointerrupter is a sensor including two elements of a light-emitting element and a light-receiving element, and measures light generated from the light-emitting element by the light-receiving element, and grasps a change in light between the elements.

The sealing resin used for the protection of the light-emitting element must be a resin having light transparency. However, the resin having light transmissivity has a problem that stress is higher than that of a black epoxy resin generally used as a sealing resin. Further, when the stress of expansion and contraction of the sealing resin due to the temperature change of the use environment is large, there is a problem that the light-emitting intensity of the light-emitting element made of GaAs (gallium gallium arsenide) is significantly deteriorated with time.

Therefore, in order to alleviate the internal stress caused by the temperature change in the use environment, it has been conventionally proposed to use two kinds of resins having different stresses as the resin of the light-emitting element wafer which is a main body portion for protecting the light-emitting element. For example, Patent Document 1 discloses a technique in which a lower layer package formed of a low-stressed epoxy-based synthetic resin is formed by directly coating an LED semiconductor wafer mounted on a circuit board, and then an upper layer package formed of an epoxy-based synthetic resin. The body is formed to cover the entire underlying package.

Patent Document 1: Japanese Laid-Open Patent Publication No. 2003-179267 (published on June 27, 2003)

Here, in order to prevent deterioration of the light-emitting intensity of the light-emitting element wafer, the region of the light-emitting element wafer that is required to be covered with the resin is a portion of the light-emitting portion (PN junction portion) of the light-emitting element wafer that is exposed outside the light-emitting element wafer. However, in the conventional technique, when the fluidity of the protective resin directly covering the light-emitting element wafer is high (for example, the viscosity of the silicone resin is 9 to 15 Pascal seconds (Pa·S)), the protective resin flows and cannot be covered. The problem of the area of the light-emitting element wafer that must be covered with a resin. Further, in order to reduce the size of the product on which the light-emitting element wafer is mounted, it is necessary to reduce the amount of the protective resin directly covering the light-emitting element wafer, and when the amount of the protective resin is too small, there is a possibility that the area of the light-emitting element wafer which must be covered with the resin cannot be covered. situation.

Further, in the technique of Patent Document 1, there is a problem that the area of the circuit board on which the LED semiconductor wafer is mounted must be increased. This is a measure for forming the epoxy-based synthetic resin after the low stress is formed so as not to allow the epoxy-based synthetic resin to flow out from the circuit board when covering the LED semiconductor wafer.

The present invention has been made in view of the above problems, and an object thereof is to provide a light-emitting element or the like which is high in quality, small in size, and thin.

In order to solve the above problems, a light-emitting element according to one aspect of the present invention includes a light-emitting element wafer and a protective resin for protecting the light-emitting element wafer, wherein the light-emitting element wafer includes a substrate and a light-emitting portion disposed on the substrate; The resin covers a side surface of the light-emitting portion including a boundary portion between the substrate and the light-emitting portion, and also covers a portion of a side surface of the substrate including the boundary portion.

Further, in the method of manufacturing a light-emitting device according to the aspect of the invention, the light-emitting element is manufactured from a light-emitting element wafer including a substrate and a light-emitting element wafer of a light-emitting portion disposed on the substrate, and includes: a first step Forming the light-emitting element wafer on the upper surface of the light-emitting element wafer opposite to the substrate, and forming the light-emitting element wafer into the light-emitting element unit having a boundary portion exceeding the light-emitting portion and the substrate a groove having a depth of position; a second step of covering the groove formed in the first step and the upper surface of the light-emitting element wafer with a protective resin; and a third step of crystallizing the light-emitting element covered in the second step The protective resin on the upper surface of the circle forms an opening in each of the light-emitting element units; and in the fourth step, after the third step, the light-emitting element wafer is divided along the groove formed in the first step The unit of the light-emitting element.

According to the aspect of the invention, the protective resin provided in the light-emitting element covers a side surface of the light-emitting portion including the boundary portion between the substrate and the light-emitting portion, and a part of the side surface of the substrate including the boundary portion. Thereby, the protective resin can surely cover at least the side surface of the light-emitting portion of the side surface of the light-emitting element wafer including the boundary portion. Further, since the protective resin covers a part of the side surface of the light-emitting element wafer, the area of the light-emitting element wafer coated with the protective resin can be reduced as compared with the case where the protective resin covers the entire side surface of the light-emitting element wafer. Therefore, the side surface of the light-emitting portion can be protected with a small amount of the protective resin. As a result, a high-quality light-emitting element can be maintained, and the size and thickness of the light-emitting element can be reduced. In addition, since the amount of the hard resin that seals the light-emitting element can be reduced, when the light-emitting element is sealed with a hard resin, the light-emitting element package including the light-emitting element and the hard resin can be reduced in size and thickness.

In addition, by coating the surface and the edge of the wafer with the protective resin before the wire bonding, it becomes possible to contact the edge of the wafer even when the metal wire is deformed by the external force or the metal wire is displaced during the filling of the mold resin. A structure that protects the resin from electrical insulation. Therefore, it is possible to prevent the occurrence of defects caused by the contact of the metal wires with the wafer elements.

(Embodiment 1) Hereinafter, an embodiment of the present invention will be described in detail. In the following description, members having the same functions as those of the members described in the respective embodiments are denoted by the same reference numerals, and the description thereof will be appropriately omitted. First, the first embodiment will be described with reference to Figs. 1 to 5 .

(Main Configuration of Light-Emitting Element 1) Fig. 1(a) is a cross-sectional view showing the configuration of a main part of a light-emitting element 1 according to an embodiment of the present invention. As shown in FIG. 1(a), the light-emitting element 1 is mounted on a first lead frame 31 made of copper or the like, and is fixed by a conductive adhesive 33 such as a silver paste. The light-emitting element 1 includes a light-emitting element wafer 2 and a protective resin 3. The light-emitting element wafer 2 is, for example, a semiconductor laser and a light-emitting diode, and an n-type semiconductor layer (hereinafter referred to as a substrate 2a) is brought into contact with the p-type semiconductor layer. The light-emitting portion 2b is a PN junction portion where the n-type semiconductor layer and the p-type semiconductor layer are in contact with each other, and when a forward voltage is applied to the light-emitting element wafer 2, light is emitted from the light-emitting portion 2b. In the example shown in Fig. 1(a), the light-emitting portion 2b is disposed on the substrate 2a.

The electrode pad 4 is placed on the surface of the light-emitting element wafer 2 on the side opposite to the first lead frame 31, and the electrode pad 4 and the second lead frame 32 made of copper or the like are electrically connected by a metal wire 5 made of gold or the like. In the following description, the surface of the light-emitting element wafer 2 on which the electrode pads 4 are disposed is referred to as the upper surface of the light-emitting element wafer 2. Further, the light-emitting portion 2b is exposed on the surface of the light-emitting portion 2b outside the light-emitting element wafer 2 (the surface including the light-emitting portion 2b at the boundary portion between the substrate 2a and the light-emitting portion 2b) as the side surface of the light-emitting portion 2b. Further, the side surface of the light-emitting element wafer 2 includes the side surface of the light-emitting portion 2b, and the side surface of the substrate 2a is included on the side surface of the light-emitting element wafer 2.

Here, the region of the light-emitting element wafer 2 which must be covered with the protective resin 3 is a portion exposed to the outside of the light-emitting element wafer 2 in the light-emitting portion 2b (PN junction portion) as described above. Therefore, as shown in FIG. 1(a), a portion where the external light-emitting portion 2b is exposed on the side surface of the light-emitting element wafer 2 is covered with the protective resin 3. Thereby, the light emission intensity of the light-emitting element wafer 2 can be prevented from deteriorating.

Fig. 1(b) is a side view showing an outline of a light-emitting element 101 as a comparative example. As shown in FIG. 1(b), the protective resin 103 is configured to cover the entire light-emitting element wafer 102. On the other hand, the protective resin 3 shown in FIG. 1(a) is a structure that covers a part of the upper surface of the light-emitting element wafer 2 and a part of the side surface of the light-emitting element wafer 2. According to this configuration, the amount of the protective resin 3 shown in FIG. 1(a) can be further reduced as compared with the amount of the protective resin 103 shown in FIG. 1(b), and the size and thickness of the light-emitting element 1 can be reduced. .

In addition, the protective resin 3 shown in FIG. 1(a) has a configuration in which the light-emitting element wafer 2 is protected to a certain thickness along the shape of the light-emitting element wafer 2 as compared with the protective resin 103 shown in FIG. 1(b). According to this configuration, the amount of the protective resin 3 shown in FIG. 1(a) can be further reduced as compared with the amount of the protective resin 103 shown in FIG. 1(b), and the size and thickness of the light-emitting element 1 can be reduced. .

(Process of Light-Emitting Element 1) FIG. 2 is a view showing an outer shape of the light-emitting element wafer 20. The light-emitting element wafer 20 is made of a material including the substrate 2a and the light-emitting element 1 of the light-emitting portion 2b disposed on the substrate 2a. The light-emitting element 1 according to the embodiment of the present invention is manufactured by covering the light-emitting element wafer 20 with the protective resin 3 and then cutting the light-emitting element wafer 20 into a unit of the light-emitting element 1. Hereinafter, the process of the light-emitting element 1 will be described.

3(a) to 3(f) are diagrams showing a procedure of manufacturing the light-emitting element 1 from the light-emitting element wafer 20. Fig. 3 (a) is a cross-sectional view taken along line A-A' of the light-emitting device wafer 20 shown in Fig. 2 . In the light-emitting element wafer 20, an n-type semiconductor layer (not shown), a light-emitting portion 2b, and a p-type light-emitting layer (not shown) are sequentially stacked on the substrate 2a.

FIG. 3(b) is a view showing a procedure of temporarily dividing the light-emitting element wafer 20 into units of the light-emitting element 1. First, the light-emitting element wafer 20 is placed on the dicing sheet 50 so that the substrate 2a faces downward (the substrate 2a is in contact with the dicing sheet 50). Next, on the upper surface of the light-emitting element wafer 20, a cutting groove 51 (groove) having a depth reaching a position exceeding a boundary portion between the light-emitting portion 2b and the substrate 2a is formed along the thickness H (first step). The dicing groove 51 is a groove for dividing the light-emitting element wafer 20 into a unit of the light-emitting element 1. For example, a cutting groove 51 (half-cut) having a depth of half the thickness H is formed from the upper surface of the light-emitting element wafer 20.

Here, the upper surface of the light-emitting element wafer 20 is a surface of the light-emitting element wafer 20 on the opposite side of the substrate 2a with the light-emitting portion 2b interposed therebetween, and is a surface on the upper side of the light-emitting element wafer 20 on the paper. Further, the direction of the thickness H is a direction in which the substrate 2a and the light-emitting portion 2b overlap.

Fig. 3 (c) is a view showing a step of performing a mesa etching process on the light-emitting element wafer 20 shown in Fig. 3 (b). The mesa etching process is a process of processing the surface of the dicing groove 51 shown in FIG. 3(b), and is a process of etching the damage removing layer of the dicing groove 51. By the mesa etching process, the surface of the dicing groove 51 shown in FIG. 3(b) is smoothed, and the mesa etching groove 52 shown in FIG. 3(c) is formed.

FIG. 3(d) is a view showing a step of covering (coating) the light-emitting element wafer 20 with the protective resin 3. The light-emitting element wafer 20 shown in FIG. 3(c) covers the upper surface of the dicing groove 51 and the light-emitting portion 2b with a protective resin 3 (second step). In the coating step in the first embodiment, the liquid of the protective resin 3 is applied onto the upper surface of the light-emitting element wafer 20 shown in FIG. 3(c), and the light-emitting element wafer 20 coated with the liquid of the protective resin 3 is rotated at a high speed. The centrifugal force forms a film of the protective resin 3 (spin coating treatment). Since the protective resin 3 coated on the upper surface of the light-emitting element wafer 20 is in a liquid state, the film of the protective resin 3 can be formed on the upper surface of the light-emitting element wafer 20 and the surface of the mesa etching groove 52 with a uniform thickness by a coating step.

The protective resin 3 is, for example, a silicone resin, a polyimide resin, or a polyurethane resin. In the resin that seals the light-emitting element, a resin having a low modulus of elasticity is preferably used. Thereby, in the above-described spin coating treatment, the film of the protective resin 3 can be made uniform, and the film of the protective resin 3 can be formed thin. As a result, the light-emitting portion 2b can be covered with a smaller amount of the protective resin 3.

Further, a cutting groove 51 is formed in the light-emitting element wafer 20. Therefore, in the spin coating process, in a state where the area of the light-emitting element wafer 2 covered with the protective resin 3 is small, the portion where the light-emitting element wafer 2 is to be protected by the resin can be stably and easily covered with the protective resin 3 2b.

Here, it is preferable that the electrode pad 4 is disposed on the upper surface of the light-emitting element wafer 20 before the coating step shown in FIG. 3(d). Further, the timing at which the electrode pads 4 are disposed on the upper surface of the light-emitting element wafer 20 is not limited to the coating step shown in FIG. 3(d). For example, the timing may be arranged after the removal step (see FIG. 3(e)) which will be described later.

Fig. 3(e) is a view showing a step of removing the protective resin 3 at an unnecessary portion. The protective resin 3 of the unnecessary portion is the protective resin 3 on the electrode pad 4. After the coating step described in FIG. 3(d), the protective resin 3 on the upper surface of the light-emitting element wafer 20 is formed with an opening for each light-emitting element unit (third step). In the removal step of the first embodiment, a photo-sensitive resist is applied to the surface of the protective resin 3 at an unnecessary portion, and exposure and development are performed by a photolithographic mask to pattern the photoresist. Next, the protective resin 3 on the electrode pad 4 is removed by etching.

By the removal step, the electrode pad 4 is not covered by the protective resin 3. When the electrode pad 4 is connected with the metal wire 5, the metal wire 5 can be sealed with a resin. Further, the protective resin 3 removed by the removal step on the upper surface of the light-emitting element wafer 20 includes not only the protective resin 3 on the electrode pad 4 but also the protective resin 3 around the electrode pad 4.

FIG. 3(f) is a view showing a step of cutting and separating the light-emitting element wafer 20 into units of the light-emitting element 1. As shown in FIG. 3(f), the light-emitting element wafer 20 shown in FIG. 3(e) is cut along the mesa etching groove 52, and the light-emitting element wafer 20 is divided into light-emitting element units 1 (fourth step). The light-emitting element 1 was fabricated by the above steps.

FIG. 4 is a plan view showing the light-emitting element wafer 20 shown in FIG. 3(f). The cutting mark 53 shown in FIG. 4 is a trace which cuts the light-emitting element wafer 20 along the mesa etching groove 52 shown in FIG. 3(f). As shown in FIG. 4, the dicing sheet 50 is stretched and expanded, and the gap between the adjacent light-emitting elements 1 becomes large. Thereby, each of the light-emitting elements 1 can be easily picked up.

(Comparison of Light-Emitting Element 1) Next, the advantages of the light-emitting element 1 will be described with reference to Figs. 5 and 6 . Fig. 5 (a) is a side view showing a state in which the light-emitting element 1 according to the embodiment of the present invention is mounted on the first lead frame 31, and Fig. 5 (b) is a view showing a state in which the light-emitting element 1 is mounted on the first lead frame 31. Top view. The light-emitting element 1 manufactured by the steps described in FIGS. 3(a) to 3(f) is mounted on the first lead frame 31 as shown in FIG. 5, and the electrode pad 4 and the second lead frame are electrically connected by the metal wire 5. .

As shown in FIG. 5(a), the protective resin 3 is configured to cover a side surface of the light-emitting portion including the boundary portion between the substrate 2a and the light-emitting portion 2b, and also covers a part of the side surface of the substrate 2a including the boundary portion. That is, the protective resin 3 is configured to cover a region from the upper surface of the light-emitting element wafer 2 to a position beyond the light-emitting portion 2b on the side surface of the light-emitting element wafer 2. With this configuration, the area where the protective resin 3 covers the light-emitting element wafer 2 can be reduced as compared with the case where the protective resin 3 covers all of the side surfaces of the light-emitting element wafer 2.

Further, as shown in FIG. 5(b), the protective resin 3 covers the upper surface of the light-emitting element wafer 2 on the side opposite to the substrate 2a with the light-emitting portion 2b interposed therebetween, and the protective resin 3 on the upper surface of the light-emitting element wafer 2 is formed with an opening. The opening is formed to expose the electrode pad 4 disposed on the upper surface of the light-emitting element wafer 2. In other words, the protective resin 3 is configured such that the upper surface of the light-emitting element wafer 2 other than the region (the region corresponding to the opening portion) in which the light-emitting element wafer 2 of the electrode pad 4 is disposed is covered on the upper surface of the light-emitting element wafer 2. In the case of this configuration, when the light-emitting element 1 is sealed by a mold resin (not shown) different from the protective resin 3, the metal wire 5 can be sealed with a resin. Further, the size of the opening of the protective resin 3 on the upper surface of the light-emitting element wafer 2 may be the same as the size of the electrode pad 4 as long as it does not prevent the metal wire 5 to be subsequently connected to the size of the electrode pad 4. It may be larger than the size of the electrode pad 4.

6(a) to 6(f) are diagrams showing a comparative example of the light-emitting element 1. The light-emitting element 101 manufactured by the conventional technique is manufactured by mounting the light-emitting element wafer 102 on the first lead frame 31, and then covering the light-emitting element wafer 102 with the protective resin 103.

Fig. 6(a) is a side view showing the light-emitting element 101 in a state where the protective resin 103 flows to the edge of the lead frame, and Fig. 6(b) is a plan view of the light-emitting element 101 shown in Fig. 6(a). The protective resin 103 has high fluidity (for example, the viscosity of the silicone resin is 9 to 15 Pascal seconds (Pa·S)). Therefore, when the light-emitting element wafer 102 is covered with the protective resin 103, the protective resin 103 flows out to the edge of the lead frame.

Fig. 6 (c) is a side view showing the light-emitting element 101 in a state in which the protective resin 103 flows to the side surface of the lead frame, and Fig. 6 (d) is a plan view of the light-emitting element 101 shown in Fig. 6 (b). The protective resin 103 covering the light-emitting element wafer 102 further flows out from the state shown in FIGS. 6(a) to 6(b), and may flow out to the side surface of the lead frame.

Fig. 6(e) is a side view showing the light-emitting element 101 in a state in which the protective resin 103 flows to the back surface of the lead frame, and Fig. 6(f) is a plan view of the light-emitting element 101 shown in Fig. 6(e). The protective resin 103 covering the light-emitting element wafer 102 further flows out from the state shown in FIGS. 6(c) to 6(d), and may cover the back surface of the lead frame.

As described above, when the light-emitting element wafer 102 is covered with the protective resin 103 having high fluidity, the shape of the protective resin 103 may be deformed. Therefore, it is not easy to provide the light-emitting element 101 manufactured using a conventional technique while maintaining a certain quality. In particular, since the protective resin 103 flows out, in the state of FIG. 6(e), the interface between the spherical neck portion of the metal wire and the protective resin overlaps, and stress tends to concentrate on the neck portion of the lead. Further, since the back surface of the lead frame is covered with the protective resin, the adhesion to the mold resin covering the light-emitting element is lowered, resulting in deterioration in quality. In addition, since the protective resin 103 flows out as shown in FIG. 6, the light-emitting element 101 is not easily miniaturized, and as a result, the size of the product in which the light-emitting element 101 is mounted is not easy.

On the other hand, in the light-emitting element 1 according to the embodiment of the present invention, as shown in FIG. 5, the protective resin 3 is configured to protect the light-emitting element wafer 2 with a constant thickness along the shape of the light-emitting element wafer 2. According to this configuration, it is possible to reduce the optical axis shift of the light-emitting element 1 and the shift unevenness of the optical axis between the plurality of light-emitting elements 1. As a result, the amount of light from the light-emitting element can be increased by the light-receiving element (not shown) used in pair with the light-emitting element, and the function of the light-emitting element can be utilized to the utmost.

Further, the protective resin 3 is a film thinner than the protective resin 103 shown in FIG. 6, and is configured to cover a part of the upper surface of the light-emitting element wafer 2 and a part of the side surface of the light-emitting element wafer 2. With this configuration, the amount of the protective resin 3 shown in FIG. 5 can be further reduced as compared with the amount of the protective resin 103 shown in FIG. 6, and the size and thickness of the light-emitting element 1 can be reduced. As a result, the size and thickness of the product in which the light-emitting element 1 is mounted can be reduced.

Further, in the light-emitting element 101 manufactured by the conventional technique, it is necessary to apply the protective resin 103 to each of the light-emitting element wafers 102 (see Fig. 6). On the other hand, in the light-emitting element 1 according to the embodiment of the present invention, as shown in FIG. 3(d), the protective resin 3 can be applied in units of the light-emitting element wafer 20. Therefore, the protective resin 3 can be applied to the plurality of light-emitting element wafers 2 by one application, and the process of the light-emitting elements 1 can be simplified.

(Process of Light-Emitting Element Package 10) A process of the light-emitting element package 10 according to the embodiment of the present invention will be described with reference to Fig. 7 . Fig. 7 (a) is a plan view showing a step of mounting the light-emitting element 1 on the first lead frame 31 (lead frame) and fixed by the adhesive 33, and Fig. 7 (b) is a side view of the step. Fig. 7 (c) is a plan view showing a step of electrically connecting the electrode pad 4 and the second lead frame 32 by the metal wires 5 after the steps of Figs. 7 (a) to (b), and Fig. 7 (d) is the step of Side view.

Fig. 7 (e) is a view showing a step of sealing the light-emitting element 1 by the mold resin 11 (hard resin) after the steps of Figs. 7 (c) to (d), and Fig. 7 (f) is a side view of the step. . The mold resin 11 is a resin which is harder than the protective resin 3, and seals the light-emitting element 1 and the first lead frame 31. More specifically, as shown in FIG. 7(f), the mold resin 11 seals the light-emitting element 1 and further seals the entire metal wire 5, and also seals the back surface of the first lead frame 31 and the back surface of the second lead frame 32.

The mold resin 11 is a resin which is harder than the protective resin 3, and the protective resin 3 is less stressful than the mold resin 11. For example, when a silicone resin, a polyimide resin, or a urethane resin is used as the protective resin 3, an epoxy resin is used as the mold resin 11. By the above steps, the light-emitting element package 10 in which the light-emitting element 1 is sealed with the mold resin 11 is manufactured.

(Comparison of Light-Emitting Element Package 10) FIGS. 8(a) to 8(h) are diagrams showing a procedure of manufacturing the light-emitting element package 110 by a conventional technique. In the step of FIG. 8, the timing of applying the protective resin 103 is different from the step shown in FIG.

Fig. 8(a) is a plan view showing a step of mounting the light-emitting element wafer 102 on the first lead frame 31 and fixing it by the adhesive 33, and Fig. 8(b) is a side view showing the step. Further, in FIGS. 8(a) to 8(b), since the light-emitting element wafer 102 is not covered with the protective resin 103, the light-emitting portion 102b is exposed to the outside.

8(c) shows a step of electrically connecting the electrode pad 4 disposed on the upper surface of the light-emitting element wafer 102 and the second lead frame 32 by the metal wires 5 after the steps of FIGS. 8(a) to 8(b). In plan view, Figure 8(d) is a side view of this step.

Fig. 8(e) is a plan view showing a step of covering the light-emitting element wafer 102 with the protective resin 103 after the steps of Figs. 8(c) to (d), and Fig. 8(f) is a side view of the step. As shown in FIG. 8(f), the metal wire 5 is in a state in which the portion on the side of the light-emitting element wafer 102 is covered with the protective resin 103. Further, since the entire light-emitting element wafer 102 is covered, the protective resin 103 has a shape that rises like a mountain.

Fig. 8(g) is a view showing a step of sealing the protective resin 103 for protecting the light-emitting element wafer 102 by the mold resin 111 after the steps of Figs. 8(e) to (f), and Fig. 8(h) is the side of the step. view. As shown in FIG. 8(h), the mold resin 111 seals the protective resin 103 covering the light-emitting element wafer 102, and further seals the portion of the metal wire 5 from the protective resin 103 to the second lead frame 32. Further, the mold resin 111 may seal the back surface of the first lead frame 31 and the back surface of the second lead frame 32. The light-emitting element package 110 in which the light-emitting element wafer 102 is sealed with the mold resin 111 is manufactured by the above-described steps of the prior art.

Here, the mold resin 111 is a resin which is harder than the protective resin 3. Therefore, in the light-emitting element package 110 shown in FIG. 8(h), the metal wire 5 is divided into a portion covered by the protective resin 103 and a portion covered by the mold resin 111. Therefore, the metal wire 5 may be easily broken due to a stress caused by a difference in linear expansion coefficient (a ratio in which the length changes depending on the temperature) of the protective resin 103 and the mold resin 111.

Fig. 9 is a table showing representative values of Young's modulus and linear expansion coefficient of various materials. Generally, the material of the mold resin 111 is an epoxy resin. As shown in FIG. 9, the linear expansion coefficient of the epoxy resin is 100 to 300 PPM/° C. In contrast, the linear expansion coefficient of the epoxy resin is 45 to 65 PPM/ °C. Further, the metal wire 5 made of gold has a coefficient of linear expansion of 14.2 PPM/°C. As described above, since the coefficient of linear expansion differs depending on the material, the amount of displacement caused by the temperature change in the use environment is different between the boundary between the protective resin 103 made of the epoxy resin and the mold resin 111 made of epoxy resin. Therefore, internal stress is generated in the metal wire 5 composed of gold. As a result, in the light-emitting element package 110 manufactured by the prior art, the metal wire 5 may be easily broken.

On the other hand, in the light-emitting element package 10 according to the embodiment of the present invention, as shown in FIG. 7(f), the metal wire 5 is configured to be covered only by the mold resin 11. Therefore, with respect to the light-emitting element 1 sealed by the mold resin 11, the metal wire 5 can be prevented from being broken by the stress caused by the difference in the linear expansion coefficient of the protective resin 3 and the mold resin.

Further, the amount of the protective resin 3 shown in Fig. 7 (f) can be further reduced as compared with the amount of the protective resin 103 shown in Fig. 8 (h). Therefore, the amount of the mold resin 11 shown in Fig. 7 (f) can be further reduced as compared with the amount of the mold resin 111 shown in Fig. 8 (h). Further, the size of the frame on which the light-emitting element wafer is mounted can be made smaller than that of the frame body of Fig. 8 . Therefore, the light-emitting element package 10 shown in FIG. 7(f) can be made smaller and thinner than the light-emitting element package 110 shown in FIG. 8(h).

(Embodiment 2) Another embodiment of the present invention will be described. In the second embodiment, a low-stress photo-photosensitive resin is used as the material of the protective resin 3 described in the first embodiment. That is, the material of the protective resin 3 used in the coating step described in FIG. 3(d) is a low-stress photo-sensitive resin. Therefore, in the removal step described in FIG. 3(e), in the second embodiment, the treatment of applying the photo-sensitive photoresist can be omitted. Further, the other steps are the same as those in the first embodiment. As described above, as the material of the protective resin 3, a low-stress photo-sensitive resin is used, whereby the step of manufacturing the light-emitting element 1 can be simplified.

(Embodiment 3) Another embodiment of the present invention will be described. In the third embodiment, the coating step using screen printing (see FIG. 3(d)), which is described in the first embodiment, is followed by a coating step using screen printing. The screen mask used for screen printing restricts the area on which the protective resin 3 is applied to the upper surface of the light-emitting element wafer 20, and is patterned so as not to apply the protective resin 3 on the electrode pad 4, which is not required to be coated. Protect the resin 3.

In the coating step in the third embodiment, after the mesa etching treatment step described in FIG. 3(c), screen printing is performed using the screen mask. Thereby, the film of the protective resin 3 is formed on the upper surface of the light-emitting element wafer 20 excluding the region on which the electrode pad 4 on which the protective resin 3 is not required to be applied. By performing the coating step using such screen printing, the removal step (third step) explained in Fig. 3(e) can be omitted. Therefore, the step of manufacturing the light-emitting element 1 can be simplified. Further, the other steps are the same as those in the first embodiment.

(Modification) In the coating step, screen printing can also be performed by using the above-described screen mask to perform screen printing. The film of the protective resin 3 formed by the coating step may have a certain thickness along the shape of the light-emitting element wafer 20 by screen printing by spraying. Therefore, when the light-emitting element wafer 2 emits light, the optical axis shift and the unevenness of the offset can be reduced. As a result, the amount of light from the light-emitting element wafer 2 can be increased by the light-receiving element used in pair with the light-emitting element, and the function of the light-emitting element wafer 2 can be utilized to the utmost.

(Integrated) A light-emitting element (1) according to a first aspect of the present invention includes a light-emitting element wafer (2) and a protective resin (3) for protecting the light-emitting element wafer, wherein the light-emitting element wafer includes a substrate (2a) and a configuration a light-emitting portion (2b) on the substrate; the protective resin covers a side surface of the light-emitting portion including a boundary portion between the substrate and the light-emitting portion, and also covers a portion of a side surface of the substrate including the boundary portion.

According to the above configuration, the protective resin provided in the light-emitting element covers a side surface of the light-emitting portion including the boundary portion between the substrate and the light-emitting portion, and a part of the side surface of the substrate including the boundary portion. Thereby, the protective resin can surely cover at least the side surface of the light-emitting portion of the side surface of the light-emitting element wafer including the boundary portion. Further, since the protective resin covers a part of the side surface of the light-emitting element wafer, the area of the light-emitting element wafer coated with the protective resin can be reduced as compared with the case where the protective resin covers the entire side surface of the light-emitting element wafer. Therefore, the side surface of the light-emitting portion can be protected with a small amount of the protective resin. As a result, a high-quality light-emitting element can be maintained, and the size and thickness of the light-emitting element can be reduced. In addition, since the amount of the hard resin (mold resin 11) that seals the light-emitting element can be reduced, when the light-emitting element is sealed with a hard resin, the light-emitting element package (10) including the light-emitting element and the hard resin can be realized. Miniaturization and thinning.

In addition, by coating the surface and the edge of the wafer with the protective resin before the wire bonding, it becomes possible to contact the edge of the wafer even when the metal wire is deformed by the external force or the metal wire is displaced during the filling of the mold resin. A structure that protects the resin from electrical insulation. Therefore, it is possible to prevent the occurrence of defects caused by the contact of the metal wires with the wafer elements.

In the light-emitting device of the second aspect of the present invention, in the first aspect, the protective resin may cover the upper surface of the light-emitting element wafer on the opposite side of the light-emitting portion, and the upper surface of the light-emitting element wafer may be protected. The resin is formed with an opening.

According to the above configuration, the protective resin formed on the upper surface of the light-emitting element wafer is formed with an opening. The opening is formed by exposing the electrode pad (4) disposed on the upper surface of the light-emitting element wafer. Therefore, when the electrode pad (4) disposed on the upper surface of the light-emitting portion is connected with the metal wire (5), the metal wire can be sealed by a resin (mold resin 11). Therefore, the breakage of the metal wire connected to the electrode pad can be suppressed by the expansion and contraction of the resin due to the temperature change. In particular, the portion of the metal wire near the electrode pad (the neck portion of the metal wire) is easily broken. Therefore, the above configuration is effective in suppressing the disconnection of the metal wire connected to the electrode pad.

In the light-emitting element of the third aspect of the invention, in the first aspect or the second aspect, the protective resin may have a constant thickness along the shape of the light-emitting element wafer.

According to the above configuration, the light-emitting element is protected by the protective resin having a certain thickness along the shape of the light-emitting element wafer. Therefore, when the light-emitting element wafer emits light, the optical axis shift and the unevenness of the offset can be reduced. As a result, the amount of light from the light-emitting element wafer can be increased by the light-receiving element used in pair with the light-emitting element, and the function of the light-emitting element wafer can be utilized to the utmost.

The light-emitting element of the fourth aspect of the invention may be any one of the above aspects 1 to 3, wherein the protective resin is a silicone resin, a polyimide resin, a polyurethane resin, or a polycarbonate resin.

According to the above configuration, the protective resin can be composed of a resin having a low stress among the resins. Therefore, the amount of the protective resin that protects the light-emitting portion can be reduced, and the thickness of the protective resin can be made constant. Therefore, downsizing and thinning of the light-emitting element can be achieved. Further, when the light-emitting element wafer emits light, the optical axis shift and the shift unevenness can be reduced, and the light-receiving element used in pair with the light-emitting element can increase the amount of light from the light-emitting element wafer.

The light-emitting element package (10) according to the fifth aspect of the invention includes the light-emitting element (1) according to the first aspect, a lead frame (first lead frame 31) on which the light-emitting element is mounted, and a hard resin (mold resin 11). And sealing the light-emitting element and the lead frame; the protective resin has less stress than the hard resin.

According to the above configuration, the hard resin that seals the light-emitting element and the lead frame has higher stress than the protective resin that protects the light-emitting element wafer, and the stress of the protective resin is lower than that of the hard resin that seals the light-emitting element. Therefore, the light-emitting element wafer can be protected with a small amount of the protective resin, and the light-emitting element can be sealed with a small amount of hard resin to manufacture the light-emitting element package. As a result, it is possible to reduce the size and thickness of the light-emitting element package.

In the method of manufacturing a light-emitting device of the sixth aspect of the present invention, a light-emitting element (1) is manufactured from a light-emitting element wafer (20) which is a material of a light-emitting element wafer including a substrate (2a) and a light-emitting portion (2b) disposed on the substrate. In the first step, the first step of forming the light-emitting element wafer on the upper surface of the light-emitting element wafer opposite to the light-emitting portion is formed to have the light-emitting element wafer divided into the light-emitting element units. a groove (cutting groove 51) exceeding a depth of a position of a boundary portion between the light-emitting portion and the substrate; and a second step of covering the groove formed in the first step and the light-emitting element wafer with a protective resin (3) In the third step, the protective resin on the upper surface of the light-emitting element wafer covered in the second step is formed with an opening portion in the light-emitting element unit; and the fourth step, after the third step, along the third step The groove formed in the first step divides the light-emitting element wafer into the light-emitting element unit.

According to the above method, the same effects as those of the above aspect 1 and the above aspect 2 can be achieved. Further, according to the above method, in step 2, the protective resin 3 is applied to the light-emitting element wafer. Therefore, the protective resin 3 can be applied to the plurality of light-emitting element wafers divided from the light-emitting element wafer by one application. Therefore, the process of applying the protective resin to the light-emitting element wafer divided from the light-emitting element wafer can be simplified as compared with the step of applying the protective resin.

In the method of producing a light-emitting device according to Aspect 7 of the present invention, in the sixth aspect, the photo-sensitive resin may be used as the protective resin in the second step. According to the above method, a photo-sensitive resin is used as the protective resin in the second step. Therefore, in the third step, the step of forming the opening portion can be simplified. More specifically, when a photo-sensitive resin is used as the protective resin, in the third step, a photo-sensitive resist is applied, and exposure and development are performed by a photolithography mask, and patterning of the photoresist is performed to form an opening by etching. . On the other hand, when a photo-sensitive resin is used as the protective resin, in the third step, exposure and development are performed by a photolithography mask to form an opening. As described above, by using a photo-sensitive resin as the protective resin, the treatment of applying the photo-sensitive photoresist can be omitted. According to the above, the step of manufacturing the light-emitting element can be simplified.

In the method of manufacturing a light-emitting device of the eighth aspect of the present invention, a light-emitting element (1) is produced from a light-emitting element wafer (20) which is a material of a light-emitting element wafer including a substrate (2a) and a light-emitting portion (2b) disposed on the substrate. In the first step, the first step of forming the light-emitting element wafer on the upper surface of the light-emitting element wafer opposite to the light-emitting portion is formed to have the light-emitting element wafer divided into the light-emitting element units. a groove (cutting groove 51) exceeding a depth of a position of a boundary portion between the light-emitting portion and the substrate; and a second step of covering the groove formed in the first step and the light-emitting element wafer with a protective resin (3) In the fourth step, after the second step, the light-emitting element wafer is divided into the light-emitting element units along the groove formed in the first step; in the second step, screen printing is performed. The protective resin on the upper surface of the light-emitting element wafer is formed with an opening in each of the light-emitting element units.

According to the above method, in the second step, the upper surface of the light-emitting element wafer can be covered with the protective resin, and the protective resin on the upper surface of the light-emitting element wafer can form an opening in each of the light-emitting element units. Therefore, the step of removing the protective resin in the region corresponding to the opening portion in order to form the opening portion of the protective resin after covering the upper surface of the light-emitting element wafer with the protective resin can be omitted. Therefore, the step of manufacturing the light-emitting element can be simplified.

In the method for producing a light-emitting device according to Aspect 9 of the present invention, in the second step of the eighth aspect, screen printing may be performed by spraying. Screen printing is performed by spraying, whereby the film of the protective resin formed in the second step may have a certain thickness along the shape of the light-emitting element wafer. Therefore, when the light-emitting element wafer emits light, the optical axis shift and the unevenness of the offset can be reduced. As a result, the amount of light from the light-emitting element wafer can be increased by the light-receiving element used in pair with the light-emitting element, and the function of the light-emitting element wafer can be utilized to the utmost.

(Additional Items) The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the claims. The embodiments obtained by appropriately combining the technical means disclosed in the different embodiments are also included in the present invention. The technical scope. Furthermore, by combining the technical means disclosed in each embodiment, new technical features can be formed.

1‧‧‧Lighting elements
2‧‧‧Lighting element chip
2a‧‧‧Substrate
2b‧‧‧Lighting Department
3‧‧‧Protective resin
4‧‧‧electrode pads
5‧‧‧Metal wire
10‧‧‧Lighting element package
11‧‧‧Mold resin (hard resin)
20‧‧‧Lighting element wafer
31‧‧‧1st lead frame (lead frame)
32‧‧‧2nd lead frame
33‧‧‧Adhesive
50‧‧‧ cutting piece
51‧‧‧Cutting trough
52‧‧‧Working surface etching groove
53‧‧‧ cut marks

Fig. 1 (a) is a cross-sectional view showing a configuration of a main portion of a light-emitting device according to an embodiment of the present invention, and Fig. 1 (b) is a side view showing an outline of a light-emitting device as a comparative example. 2 is a view showing an outer shape of a light-emitting element wafer. 3(a) to 3(f) are views showing a procedure for producing a light-emitting element according to an embodiment of the present invention. Fig. 4 is a plan view showing the light-emitting element wafer shown in Fig. 3 (f). Fig. 5 (a) is a side view showing a state in which a light-emitting element according to an embodiment of the present invention is mounted on a first lead frame, and Fig. 5 (b) is a plan view showing a state in which a light-emitting element is mounted on a first lead frame. 6(a) to 6(f) are diagrams showing a comparative example of a light-emitting element. 7(a) to 7(f) are views showing a procedure of manufacturing a light-emitting element package according to an embodiment of the present invention. 8(a) to 8(h) are diagrams showing a procedure of manufacturing a light-emitting element package by a conventional technique. Fig. 9 is a table showing representative values of Young's modulus and linear expansion coefficient of various materials.

1,101‧‧‧Lighting elements

2,102‧‧‧Lighting element chip

2a‧‧‧Substrate

2b‧‧‧Lighting Department

3,103‧‧‧Protective resin

4‧‧‧electrode pads

5‧‧‧Metal wire

31‧‧‧1st lead frame

32‧‧‧2nd lead frame

33‧‧‧Adhesive

Claims (10)

A light-emitting element comprising a light-emitting element wafer and a protective resin for protecting the light-emitting element wafer, wherein the light-emitting element wafer includes a substrate and a light-emitting portion disposed on the substrate; and the protective resin covers the substrate and the light-emitting portion The side surface of the light-emitting portion at the boundary portion also covers a portion of the side surface of the substrate including the boundary portion. The light-emitting element according to claim 1, wherein the protective resin covers the upper surface of the light-emitting element wafer on the opposite side of the light-emitting portion; the protective resin on the upper surface of the light-emitting element wafer is formed Opening. The light-emitting element of claim 1, wherein the protective resin has a certain thickness along a shape of the light-emitting element wafer. The light-emitting element of claim 2, wherein the protective resin has a certain thickness along a shape of the light-emitting element wafer. The light-emitting element according to any one of claims 1 to 4, wherein the protective resin is a silicone resin, a polyimide resin, a polyurethane resin, or a polycarbonate resin. A light-emitting element package comprising: a light-emitting element according to claim 1; a lead frame on which the light-emitting element is mounted; and a hard resin to seal the light-emitting element and the lead frame; wherein the protective resin is compared with the hard resin The stress is small. A method of manufacturing a light-emitting element, comprising: manufacturing a light-emitting element from a light-emitting element wafer including a substrate and a material of a light-emitting element wafer disposed on a light-emitting portion of the substrate, comprising: a first step of sandwiching the light-emitting element a portion of the light-emitting element wafer on the opposite side of the substrate, and a groove for dividing the light-emitting element wafer into the light-emitting element unit and having a depth reaching a position exceeding a boundary portion between the light-emitting portion and the substrate In the second step, the groove formed in the first step and the upper surface of the light-emitting element wafer are covered with a protective resin; and the third step is the upper surface of the light-emitting element wafer covered by the second step The protective resin forms an opening in each of the light-emitting element units; and in the fourth step, after the third step, the light-emitting element wafer is divided into the light-emitting element units along the groove formed in the first step. The method for producing a light-emitting device according to claim 7, wherein in the second step, a photo-sensitive resin is used as the protective resin. A method of manufacturing a light-emitting element, comprising: manufacturing a light-emitting element from a light-emitting element wafer including a substrate and a material of a light-emitting element wafer disposed on a light-emitting portion of the substrate, comprising: a first step of sandwiching the light-emitting element a portion of the light-emitting element wafer on the opposite side of the substrate, and a groove for dividing the light-emitting element wafer into the light-emitting element unit and having a depth reaching a position exceeding a boundary portion between the light-emitting portion and the substrate In the second step, the groove formed in the first step and the upper surface of the light-emitting element wafer are covered with a protective resin; and the fourth step, after the second step, along the groove formed in the first step Dividing the light-emitting element wafer into the light-emitting element unit; in the second step, by performing screen printing, the protective resin on the upper surface of the light-emitting element wafer is formed with an opening portion in the light-emitting element unit . A method of producing a light-emitting device according to claim 9, wherein in the second step, screen printing is performed by spraying.