JP2013065891A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device which achieves high flexibility for the reduction of the size and the film thickness of the device and the mounting to a circuit board while maintaining high heat radiation performance.SOLUTION: A semiconductor device of the invention includes: a semiconductor element; and a package 10 where the semiconductor element is disposed. The package 10 has a heat conductive member 12 below conductor wiring connecting with the semiconductor element, and the heat conductive member 12 is disposed below the semiconductor element and is buried inside an insulation member for forming the package 10.

Description

The present invention relates to a semiconductor device on which a semiconductor element is mounted, and more particularly to a semiconductor device that can efficiently release heat generated in the semiconductor element.

With recent downsizing and thinning of electronic devices, the demand for light-emitting devices that can be surface-mounted on a circuit board is rapidly increasing.

In this type of light emitting device, for example, an electrode is disposed under the LED chip, the electrode is processed so as to wrap around the side surface or the back surface of the light emitting device, and by placing the light emitting device on the circuit board, The light emitting device is configured to be connected to the conductor wiring of the circuit board. The surface of the chip is sealed with an epoxy resin or the like that is a sealing resin.

In such a light-emitting device, the deterioration of the chip is remarkably accelerated by the heat generated by the LED chip itself. Therefore, the temperature rise of the LED chip is suppressed by improving the heat dissipation characteristics.
It is known to extend the life of ED chips.

Also, blue light emitting diodes and white light emitting diodes that convert blue light from blue light emitting diodes into white light and output them have higher radiation energy than red light emitting diodes, and therefore sealing resin that seals LED chips. However, it deteriorates by the emitted light of the LED chip, and turns brown. Such a color reaction of the sealing resin is a photochemical reaction, but it is also known that the reaction rate increases as the temperature of the sealing resin increases.

In order to prevent such problems caused by heat generation of the semiconductor element, for example, Patent Document 1
Has proposed a light emitting device in which a heat dissipation member is included in a substrate on which an LED chip is mounted to dissipate heat generated by the LED chip.

However, in this light emitting device, since the heat dissipation member is included in the substrate, that is, the heat dissipation member is covered with the insulator constituting the substrate, the insulator is disposed in the heat dissipation path, and sufficient heat dissipation is obtained. In addition, since the heat dissipating member is exposed on a part of the side surface and the back surface, there is a problem that a short circuit occurs or restrictions in processing the electrode occur.

On the other hand, for example, in Patent Document 2, LE is directly applied on a substrate made of aluminum or the like.
There has been proposed a light source device that suppresses the temperature rise of the LED chip by arranging the D chip by thermal coupling. Certainly, LE is directly applied to a member having thermal conductivity such as an aluminum substrate.
By disposing D, sufficient heat dissipation is ensured.

When this light source device is a surface mount device (SMD: Surface Mount Device), it is necessary to form a terminal for external connection on the back surface. When a member having thermal conductivity is used as a substrate, There is a problem that various structural constraints increase, such as the area of the external connection terminal being reduced on the back surface, and accompanying this, the adhesion by soldering to the circuit board is reduced.

In the inventions described in Patent Documents 3 and 4, the heat conductive member is completely embedded in the insulating member constituting the substrate, and the heat dissipation is higher than that of the prior art disclosed in Patent Document 1 described above. It is possible to provide a high degree of freedom in miniaturization and thinning of the device, mounting on a circuit board, and the like while maintaining performance.

JP 2001-111116 A JP 2002-94122 A JP 2001-127224 A JP 2001-189534 A

However, if a thermally conductive member containing a metal material is embedded in an insulating member such as ceramics or resin, there is a concern that the adhesion between different materials may decrease. Specifically, when a material containing tungsten and copper is used as the heat conductive member and alumina is used as the material of the insulating member, peeling may occur at the interface between the heat conductive member and the insulating member. Therefore, there is a possibility that the connection between the upper layer and the lower layer of the insulating member sandwiching the heat conductive member cannot be maintained. On the other hand, if the amount of the heat conductive member is reduced in an attempt to ensure the connection between the upper layer and the lower layer of the insulating member, the heat dissipation performance is lowered.

Therefore, the present invention maintains the connection between the upper layer and the lower layer of the insulating member sandwiching the heat conductive member, without relatively reducing the amount of the heat conductive member relative to the insulating member, It aims at improving heat dissipation.

A semiconductor device according to the present invention is a semiconductor device comprising a semiconductor element and a package having a recess for accommodating the semiconductor element, and a thermally conductive member embedded in an insulating member constituting the package. The side wall of the recess has a stepped portion between the outermost side wall forming the recess and the mounting portion of the semiconductor element provided on the bottom surface of the recess. It is characterized by extending from below the mounting portion to below the step portion.

An insulating member constituting the package is 0.1 between the conductor wiring and the heat conductive member.
It is preferable to be arranged with a thickness of mm or less.

The package has an external connection terminal on the back surface, and an insulating member constituting the package is disposed with a thickness of 0.1 mm or less between the external connection terminal and the heat conducting member. preferable.

The insulating member of the package preferably contains ceramic as a material. Moreover, it is preferable that the said heat conductive member contains CuW as a material.

As in the present invention, according to the semiconductor device in which the heat conductive member is embedded inside the package and below the conductor wiring, the heat generated from the semiconductor element can be efficiently released,
Since it is possible to overlap the conductor wiring and the heat conductive member, downsizing of the semiconductor device,
While realizing a thin film, it is possible to secure a degree of freedom in designing a light emitting element while minimizing structural constraints such as electrode processing.

In the package in which the heat conductive member is embedded in the insulating member as described above, the present invention provides:
To improve the heat dissipation without reducing the amount of the heat conductive member relative to the insulating member while maintaining the connection between the upper layer and the lower layer of the insulating member with the heat conductive member interposed therebetween. Can do. That is, according to the present invention, among the side walls of the insulating member that forms the recesses of the package, a part of the stepped portion outside the side surface of the heat conductive member and the outermost side wall that forms the recesses, As a result, it is possible to secure the connection between the insulating members on the upper side and the lower side of the heat conductive member and maximize the heat conductive member in the horizontal direction (that is, the direction perpendicular to the thickness direction of the heat conductive member). In addition, heat dissipation of the package can be ensured.

The semiconductor element is a light-emitting element having a semiconductor layer stacked on a support substrate containing a metal material, and the light-emitting element is disposed in the package with the support substrate facing the heat conductive member. preferable. Thereby, the heat dissipation from a light emitting element is improved, and it can be set as a high output light-emitting device.

The inner wall of the recess provided in the package has a stepped portion on the outside of the mounting portion of the semiconductor element, and an insulating portion that separates the conductor wiring disposed on the upper surface of the stepped portion as a pair of positive and negative electrodes,
It is preferable that the light emitting element is provided in a diagonal direction in the outer shape of the light emitting element. Furthermore, it is preferable that the said insulation part is a sector shape centering on the corner | angular of the external shape of a light emitting element. This
Light loss due to the insulating member constituting the package can be reduced, and a light-emitting device with high light extraction efficiency can be obtained.

It is preferable that the extending directions of the plurality of conductive wires extended from the light emitting element arranged in the package to the conductor wiring on the upper surface of the stepped portion in the recess are substantially perpendicular to each other. As a result, the occurrence rate of wire breakage is reduced, so that a highly reliable semiconductor device can be obtained.

The best mode for carrying out the present invention will be described below with reference to the drawings. However,
The embodiments described below exemplify a semiconductor device for embodying the technical idea of the present invention, and the present invention does not limit the semiconductor device to the following.

Moreover, this specification does not specify the member shown by the claim as the member of embodiment. The dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments are not intended to limit the scope of the claims of the present invention only, unless otherwise specified. Only. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Further, in the following description, the same name and reference sign indicate the same or the same members, and detailed description will be omitted as appropriate. Furthermore, each element constituting the semiconductor device of the present invention may be configured such that a plurality of elements are configured by the same member and the plurality of elements are shared by one member. It can also be realized by sharing these members.

FIG. 1 is a plan view showing a package of a semiconductor device in this embodiment. 2 is a vertical sectional view taken along the line II-II shown in FIG. FIG. 3 is a rear view showing the package of the semiconductor device in this embodiment. FIG. 4 is a plan view of a semiconductor device in which a semiconductor element is mounted on the package shown in FIG.

As shown in FIG. 2, the side wall of the recess in the package of the semiconductor device has a stepped portion between the semiconductor element mounting portion disposed on the bottom surface of the recess, and the package has an insulating property that constitutes the package. A thermally conductive member embedded in the member, and the thermally conductive member is substantially perpendicular to the thickness direction of the thermally conductive member from below the mounting portion of the semiconductor element to below the stepped portion. Is extended in the direction.

As shown in FIG. 4, the semiconductor device of the present invention is mainly composed of a semiconductor element 14 and a package 10 in which conductor wirings 11, 11aa, 11ab, and 11b are formed.

The semiconductor element is usually a semiconductor light emitting element, and in particular, a semiconductor light emitting element called a so-called light emitting diode is preferable. For example, on the substrate, InN, AlN, GaN,
Examples thereof include those in which a laminated structure including an active layer is formed by various semiconductors such as nitride semiconductors such as InGaN, AlGaN, and InGaAlN, III-V compound semiconductors, and II-VI compound semiconductors. Among them, those having an active layer that emits blue light made of a nitride semiconductor are preferable. The emission wavelength of the obtained light-emitting element varies depending on the semiconductor material, the mixed crystal ratio, the In content of InGaN in the active layer, the type of impurities doped in the active layer, etc.
It can be changed from the ultraviolet region to red.

The semiconductor element may be either one having both positive and negative electrodes on the same side with respect to the active layer or one having positive and negative electrodes on different sides with respect to the active layer.

FIG. 8 shows a cross-sectional view of a light emitting element having a pair of positive and negative electrodes on different sides with respect to the active layer as an example of a semiconductor element constituting the semiconductor device of this embodiment. The light-emitting element 14 includes a support substrate 19 made of a metal, a bonding layer 20 formed on one main surface of the support substrate 19, and a p-type semiconductor layer 21 formed on the bonding layer 20. , An active layer 22 formed on the p-type semiconductor layer 21, an n-type semiconductor layer 23 formed on the active layer 22, and an n-type semiconductor layer 2
3 and an n-side electrode 24 formed on the substrate 3. Here, the bonding layer 20 is a eutectic material (for example, solder or AuSn eutectic material) for bonding the p-type semiconductor layer 21 and the support substrate 19.
It is the layer which consists of. Further, for example, Si or CuW can be used as the metal material of the support substrate 19. Further, the eutectic material 25 (for example, Au, S) is formed on the other main surface of the support substrate 19.
(eutectic material made of n or the like) and a conductive adhesive for fixing to a package. The support substrate 19 or the eutectic material 25 side is a p-side electrode.

As described above, a light-emitting element formed using a metal material as a supporting substrate can be provided with positive and negative electrodes on different sides with respect to the active layer, and one surface of the supporting substrate can be used as a mounting surface. . That is, such a light emitting element is disposed on an insulating layer covering the thermally conductive member of the present invention or a conductor wiring disposed on the insulating layer, with one surface of the support substrate being a mounting surface on the package. Is done. Thereby, the support substrate which forms the mounting surface of a light emitting element can be used as a heat dissipation path. Therefore, since heat dissipation from the light-emitting element can be improved as compared with a light-emitting element using a sapphire substrate as a support substrate, a semiconductor device with high light emission output can be obtained.

The semiconductor element is placed on a conductor wiring in a package, which will be described in detail later, preferably on either a positive or negative electrode, or on a separately provided placement region. Usually, for example, using a resin such as epoxy resin, silicone, solder such as Au—Sn eutectic, brazing material such as low melting point metal, conductive paste such as silver, gold, palladium, etc. It can be die bonded to the region.

The electrodes formed on the semiconductor element are connected to the conductor wiring in the package. When the semiconductor element has positive and negative electrodes on the same surface side, it is preferable to wire bond the positive electrode of the semiconductor element and the positive electrode of the package, and the negative electrode of the semiconductor element and the negative electrode of the package. In addition, when the positive and negative electrodes of the semiconductor element are provided on the upper surface side and the back surface side of the semiconductor element, the electrode on the back surface side is usually die-bonded by placing the semiconductor element on one electrode of the package. Thus, it is connected to one electrode of the package.

In the semiconductor device, not only one semiconductor element but also a plurality of semiconductor elements may be mounted. In this case, a plurality of semiconductor elements that emit light of the same emission color may be combined, or a plurality of semiconductor elements having different emission colors may be combined so as to correspond to RGB. When a plurality of semiconductor elements are mounted, the semiconductor elements may be electrically connected to the electrodes of the package so as to have any connection relationship such as parallel or series.

In addition, a protective element may be mounted on the semiconductor device of the present invention. There may be one protective element or a plurality of protective elements. Further, it may be formed inside the package so that the light from the semiconductor element is not shielded by the protective element, or may be a package with a special recess for housing the protective element. Here, the protective element is not particularly limited, and may be any known element mounted on the semiconductor device. For example, overheating, overvoltage, overcurrent, a protection circuit, an electrostatic protection element, and the like can be given. Specifically, a Zener diode, a transistor diode, or the like can be used.

The package 10 is not particularly limited as long as it is a form generally used for manufacturing this type of semiconductor device, but at least the insulating layers 10a, 10b, 10 made of ceramics.
c, 10d, 10e, 10f, and conductor wirings 11, 11aa connected to the semiconductor element 14,
11 ab and 11 b and a heat conductive member 12 embedded in the package 10 and below the conductor wirings 11 and 11 aa through insulating layers 10 e and 10 g.

The package 10 is usually formed of the above-described insulating layers 10a, 10b, 10c, 10d, 10e,
Insulating materials having various patterns of 10f and 10g are laminated in multiple layers. By using such a package, there is little warpage and flatness can be secured,
Solder crack resistance can be realized.

Examples of ceramics include alumina, mullite, forsterite, glass ceramics, ordinary porcelain, nitride (AlN), carbide (SiC), and the like. Among these, ceramics made of alumina or mainly composed of alumina is preferable.

Further, the package may have an insulating layer made of an insulating material other than ceramics in a part thereof. Examples of such a material include BT resin, glass epoxy, epoxy resin, and the like.

The package may have a substantially flat surface, but preferably has a recess for mounting a semiconductor element. Thereby, the electrode formed on the surface of the semiconductor element,
It is possible to minimize the distance from the conductor wiring described later, and it is possible to reliably connect the two with a wire or the like. The size of the recess is not particularly limited, and can be appropriately adjusted depending on the size and number of semiconductor elements to be mounted.

Conductor wirings 11, 11aa, 11ab, and 11b formed in the package are portions that function as positive and negative electrodes connected to the positive and negative electrodes of the semiconductor element on the upper surface of the package, that is, the mounting surface of the semiconductor element. 11aa, 11ab, 11b and a portion (not shown) that functions as a wiring penetrating or continuously formed from the upper surface to the back surface side of the package;
On the back surface or side surface of the package, that is, with a portion 11 that functions as an external connection terminal when mounted on a circuit board. These conductor wirings are usually Ni,
It is formed of a single layer or a plurality of layers of a metal or alloy layer mainly composed of Au, Cu, Ag or the like. In addition, these conductor wirings can be formed on the package surface by vapor deposition or sputtering and photolithography processes, printing methods, etc., or by electrolytic plating. In the case of an electrode material or the like, it can be formed as a ceramic green sheet by a printing method, lamination, or the like. Thereby, when dicing a board | substrate, the shape which does not cut | disconnect an electrode part can be formed easily. Therefore, processing can be performed easily and accurately without generating burrs or the like.

As shown in FIG. 2 and FIG. 3, the package 10 has a thermally conductive member 12 in its interior.
To be embedded. Here, the term “embedding” refers to a state in which the entirety of the thermally conductive member 12 is almost completely covered with an insulating layer constituting the package 10. Thereby, the top surface or the back surface of the package can be arranged so that the conductor wirings 11, 11 aa, 11 ab, 11 b and the heat conductive member 12 overlap each other in plan view, thereby further reducing the size of the semiconductor device. In addition to being able to be realized, it is possible to reliably prevent a short circuit between the conductor wiring, the wiring on the circuit board, etc., or the electrode.

Moreover, in order to match the arrangement pattern of the conductor wiring arranged on the heat conductive member with the shape of the planar extension of the heat conductive member, the arrangement pattern of the conductor wiring includes other than the mounting portion of the semiconductor element and the wire bonding portion. In addition, it is preferable to provide an extra extension that covers the periphery of the heat conductive member as viewed in plan. That is, the arrangement pattern of the conductor wiring has an extension portion that is connected to the mounting portion of the semiconductor element and the wire bonding portion and extends from those portions to the peripheral portion of the thermally conductive member. Thereby, the heat dissipation from the semiconductor element arrange | positioned to conductor wiring to a heat conductive member can further be improved.

The heat conductive member is, for example, about 100 W / (m · K) or more, preferably 200 W.
There may be mentioned those having a thermal conductivity of about / (m · K) or more. For example, ceramics such as aluminum nitride, copper, aluminum, gold, silver, tungsten, iron, nickel or other metals or iron-nickel alloys, phosphor bronze, iron-containing copper, CuW or silver, aluminum, copper, Although it can be formed by using a metal plating film such as gold, CuW is preferable. Thus, the green sheet can be formed simultaneously with the package by forming, stacking, firing, or the like.

The heat conductive member 12 is suitably, for example, 0.05 mm or more and 0.5 mm or less in thickness.

On the upper surface of the package, that is, the mounting surface of the semiconductor element, the heat conductive member 12 is disposed below the conductor wiring 11aa via the insulating layer 10e that constitutes the package 10. In this case, the thickness of the insulating layer 10e is 0.05 mm or more and 0.1 mm or less, preferably 0.09 mm or less, more preferably 0.08 mm or less. By using such a thin film, it is possible to ensure sufficient heat dissipation by the heat conductive member and ensure insulation as much as placing the semiconductor element directly on the heat conductive member. However, the semiconductor device can be reduced in size by overlapping with the conductor wiring that becomes an electrode for connecting to the electrode of the semiconductor element.

As shown in FIG. 3, on the back surface of the package 10, that is, the mounting surface on the circuit board, the heat conductive member 12 is disposed below the conductor wiring 11 through the insulating layer 10 g constituting the package 10. Has been placed. In this case, the thickness of the insulating layer 10g is 0.1 mm or less, preferably 0.09 mm or less, more preferably 0.08 mm or less. By using a thin film as described above, it is possible to sufficiently ensure heat dissipation from the back surface of the package 10 by the heat conductive member 12. Furthermore, while ensuring insulation, it can be overlapped with the conductor wiring that becomes the external terminal, and while realizing a reduction in the size of the semiconductor device, it increases the surface area of the external terminal and increases the contact area with the circuit board. Therefore, it is possible to improve the adhesion by minimizing the influence of solder cracks and the like.

Note that, in addition to the conductor wiring, the package may additionally have a region in which the same material as the conductor wiring is formed in order to place the semiconductor element.

In the semiconductor device of the present invention, the upper part of the semiconductor element arranged in the package is usually
It is covered with a sealing resin. FIG. 5 is a perspective view of a semiconductor device in which a sealing resin is formed on the front surface of the package 10 shown in FIG. As shown in FIG. 5, the sealing resin can have various shapes in consideration of optical characteristics such as a convex lens shape for condensing light from the light emitting element in the front direction. Such a sealing resin material is not particularly limited as long as it has translucency. For example, polyolefin resin, polycarbonate resin, polystyrene resin, epoxy resin, acrylic resin, acrylate resin, One or more resins such as methacrylic resin (PMMA, etc.), urethane resin, polyimide resin, polynorbornene resin, fluororesin, silicone resin, modified silicone resin, modified epoxy resin, liquid crystal polymer, etc. It can be selected from the materials used. Of these, epoxy, silicone, modified silicone, urethane resin, oxetane resin and the like are suitable.

Here, what has translucency should just be what can permeate | transmit light to the extent which can observe the light from a semiconductor element through sealing resin. Such resins include, for example, phosphors or pigments,
Additional components such as a filler or a diffusing material may be contained. These additional components are not particularly limited, and examples thereof include phosphors, pigments, fillers, and diffusion materials described in WO2006 / 038502 and JP2006-229055. The sealing member is preferably formed in a shape that covers the semiconductor element, the positive and negative electrodes, and the entire wire.

  Embodiments of a semiconductor device according to the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a plan view showing a package of a semiconductor device in this embodiment. 2 is shown in FIG.
It is sectional drawing of the perpendicular direction in the II-II line in the top view shown in FIG. FIG. 3 is a rear view showing the package of the semiconductor device in this embodiment. FIG. 8 is a cross-sectional view of the light-emitting element in this example.

As shown in the plan view of FIG. 1, the cross-sectional view of FIG. 2, and the rear view of FIG. 3, the semiconductor device of this embodiment is formed on the upper surface of an insulating package 10 made of alumina ceramics having a substantially rectangular parallelepiped shape. A recess 13 is formed.

As shown in FIG. 2, the side wall of the recess in the package of the present embodiment is partially insulated from the mounting portion of the semiconductor element disposed on the bottom surface of the recess, and the insulating layer 10 c and the insulation are partially projected into the recess. And a step portion formed by the layer 10d. The package includes a thermally conductive member 12 embedded in an insulating member constituting the package, and the thermally conductive member 12 extends from below the semiconductor element to below the step portion. That is, the heat conductive member 1
The two side surfaces are arranged between the inner wall surface of the stepped portion in the recess of the package and the inner wall surface of the insulating layer 10b forming the uppermost surface of the side wall of the package. As described above, the thickness of the insulating member is changed from the outermost side wall forming the recess of the package toward the center of the heat conductive member 12 (the mounting portion of the semiconductor element) and the inclined surface and step of the side wall. Reduce the thickness step by step. Further, the insulating layers 10b, 10c, 10 are arranged outside the side surface of the heat conductive member 12.
By d, 10e, 10f, and 10g, the connectivity between the upper layer and the lower layer of the insulating member sandwiching the heat conductive member 12 is improved. At the same time, since the thermally conductive member 12 is maximized in the horizontal direction, the heat dissipation of the package by the thermally conductive member 12 can be improved.

2 and 3, the conductor wiring 11aa for mounting the light-emitting element 14 and the conductor wirings 11ab and 11b functioning as positive and negative electrodes are spaced apart from each other on the bottom surface of the recess 13 of the package 10. Exposed.

The package 10 includes insulating layers 10a to 10g made of ceramics and a conductor wiring 11a.
As a laminated structure with the layers constituting a, 11ab, and 11b, they are integrally formed by firing from a ceramic green sheet. In FIG. 2, the conductor wirings 11aa, 11
In order to make the arrangement of ab easy to understand, the film thickness is exaggerated. In FIG. 2 (hereinafter, the same applies to FIG. 7), the boundary lines of the insulating layers 10a to 10g indicate that the package of this embodiment is a laminate of a plurality of ceramic green sheets having various shapes. In addition, a solid line is shown for easy understanding of the laminated structure. However, in an actual package, the boundary lines of the insulating layers 10a to 10g are not always clear as illustrated.

Usually, as shown in FIG. 4, the light emitting element 14 is mounted in a region indicated by a broken line inside the conductor wiring 11aa in FIG. The light emitting element 14 has an n electrode on the upper surface and a p electrode on the lower surface, and the conductor wiring 11b functioning as the n electrode is electrically connected to the n electrode on the upper surface of the light emitting element 14 by the wire 16. . Further, the conductor wiring 11aa on which the light emitting element 14 is placed.
, 11ab are connected inside the package 10 and have the same potential. Conductor wiring 11
aa, 11ab, and 11b are conductor wirings 1 arranged inside the package 10 and at a part of the side surface.
1, conductor wiring 11 that functions as two positive and negative electrodes exposed on the back surface of the package 10.
(See FIG. 3). Further, the protective element 15 is formed on the conductor wiring 11ab.
Is placed and is electrically connected to the other conductor wiring 11b and the wire 16.

In FIG. 1, FIG. 3, FIG. 4 and FIG. 6, the range where the heat conductive member 12 exists inside the recess 13 of the package 10 is indicated by a broken line. That is, inside the recess 13 and below the conductor wiring 11aa for mounting the light emitting element and a part of the conductor wirings 11ab and 11b functioning as positive and negative electrodes, the insulating layer 10e (thickness) constituting the package 10 is formed. About 0.05 mm) through C
A thermally conductive member 12 (thickness: about 0.175 mm) made of uW is embedded. Further, the heat conductive member 12 is completely covered with an insulating layer 10 g (thickness: about 0.05 mm) constituting the package 10 also on the back surface of the package 10. As shown in FIG. 4, the heat conductive member 12 is arranged in a shape substantially concentric with the opening when viewed from the opening direction of the recess of the package 10 and smaller than the area of the opening of the recess. The light emitting element 14 is formed with an area larger than the outer shape of the light emitting element 14. By adjusting the size of the heat conductive member in this way, light emission is suppressed while suppressing deformation of the package due to the difference in physical properties between the insulating member and the heat conductive member constituting the package and variations in the shape of each package. The heat dissipation from the element can be improved to the maximum.

In the recess 13 of the package 10, exposed conductor wirings 11aa, 11ab, 11b
, The light emitting element 14, the protective element 15 and the wire 16 so as to completely cover the sealing member (FIG. 5).
Reference) is formed. As the sealing member, for example, an epoxy resin mixed with a YAG phosphor at a predetermined ratio is used, and the sealing member is formed in a lens shape protruding upward.

Further, as another semiconductor device, one in which the insulating layers 10e and 10g were changed as shown in [Table 1] was manufactured. The thermal resistance values of the semiconductor devices having these configurations were measured. The results are shown in [Table 1] below.

According to the semiconductor device of the present embodiment, the thermal conductive member is embedded in the package and below the conductor wiring, so that the semiconductor element is directly mounted on the thermal conductive member.
It becomes possible to ensure sufficient heat dissipation by the heat conductive member, and heat generated from the light emitting element can be efficiently released.

In addition, in order to ensure insulation, it is possible to overlap the conductor wiring and the heat conductive member while reliably preventing a short circuit between the conductor wiring, the wiring in the circuit board, etc. or the electrode,
The semiconductor device can be reduced in size and thinned, and structural constraints such as electrode processing can be minimized to ensure flexibility in the design of the light emitting element.

The package 10 in this embodiment has a stepped portion in the recess 13 in which the light emitting element 14 is disposed. Specifically, as shown in FIG. 2 (the same applies to FIG. 7), the step portion is formed in the recess 13 by the insulating layer 10c and the insulating layer 10d among the insulating layers constituting the package 10. . Due to the stepped portion, the package 10 further has a second concave portion in which the light emitting element 14 is accommodated inside the first concave portion having a circular opening from the upper surface direction. The opening of the second recess has an opening area smaller than that of the first recess and has a quadrangular shape substantially similar to the outer shape of the light emitting element 14. The step portion is a portion provided between the opening of the first recess and the bottom surface of the recess of the package. The first recess is formed by an upper surface of the stepped portion and an inner wall surface extending from the upper surface toward the upper surface of the package. On the other hand, the second recess is formed by an inner wall surface connected to the upper surface of the stepped portion and extending from the upper surface toward the back surface of the package and the lowermost surface of the recess of the package. Further, the package 10 has conductor wirings 11ab and 11b on the upper surface of the stepped portion, and the conductor wirings 11ab and 11b are made of a metal having high reflectivity including Ag as a material of the outermost surface.

Here, as shown in FIG. 8, the light-emitting element 14 in this example is formed by laminating a semiconductor layer including an active layer 22 on a support substrate 19 made of silicon (Si). The light emitting element 14 is accommodated in the second recess, and the lower surface of the support substrate 19 (that is, the surface opposite to the surface on which the semiconductor layers are stacked) is disposed on the bottom surface of the second recess. Conductor wiring 11aa
And a conductive adhesive such as AuSn paste.

Further, the thickness of the support substrate 19 of the light emitting element 14 is such that when the light emitting element 14 is disposed on the bottom surface of the second recess, the top surface of the light emitting element 14 protrudes from the opening of the second recess. The thickness is such that at least a part of the active layer 22 can be seen from the opening of the second recess. Further, the conductor wirings 11ab and 11b arranged on the upper surface of the step are arranged with a thickness that allows light from the active layer 22 of the light emitting element 14 to be incident on the surface of the conductor wiring.

Here, even if the active layer of the light emitting element 14 is too far from the surface of the conductor wiring, the light from the active layer is attenuated before reaching the surface of the conductor wiring. Therefore, when the light emitting element 14 as shown in FIG. 8 is mounted in the second recess of the package, it is preferable that the active layer of the light emitting element 14 be as close as possible to the surface of the conductor wiring. Specifically, the depth of the second recess is preferably provided so that the surface of the conductor wiring serving as the reflection surface is located between the upper limit of the p-type semiconductor layer 21 and the lower limit of the bonding layer 20. Further, since the bonding layer 20 is thicker than the semiconductor layer, the height of the plane extending the surface of the conductor wiring across the bonding layer 20 is considered in consideration of the ease of adjustment when mounting the light emitting element. It is preferable to do.

Thereby, the light emitted from the active layer of the light emitting element 14 is reflected in the opening direction of the concave portion using the surface of the conductor wirings 11ab and 11b disposed on the upper surface of the step as a reflection surface. Therefore, light loss in the recess of the package is reduced, and light from the light emitting element can be efficiently emitted outside the light emitting device.

When the rectangular light-emitting element 14 is viewed from the upper surface side, light emission is considered to be less at a portion (corner) including the intersection of each side forming the outer shape of the light-emitting element 14 as compared with other portions. . Therefore, a part of the insulating member made of ceramics may be exposed on the upper surface of the step without providing conductor wiring in the extension direction of the diagonal line in the outer shape of the light emitting element 14. In other words, from the viewpoint of reducing light absorption due to exposure of the insulating member and improving light extraction, the insulating separation of the conductor wiring 11ab and the conductor wiring 11b having different polarities is the upper surface of the step portion, and It is preferable that the light emitting element is formed in a diagonal direction in the outer shape of the light emitting element.

The conductor wiring 11ab in the package of the present embodiment is continuously provided in an L-shaped pattern shape facing two adjacent sides among the sides constituting the outer shape of the light emitting element 14 when the light emitting device is viewed from the upper surface direction. In addition, the conductor wiring 11b has the center of the recess as the axis of symmetry and the conductor wiring 11b.
In an L-shaped pattern shape that is substantially point-symmetric with ab, the light-emitting element 14 is continuously provided so as to face two adjacent sides among the sides forming the outer shape of the light-emitting element 14. The conductor wiring 11ab and the conductor wiring 11b are insulated and separated between the two L-shaped shapes (two locations on the upper surface of the step) in the diagonal direction of the outer shape of the light emitting element 14. In other words, the insulating portions of the conductor wiring 11ab and the conductor wiring 11b in the present embodiment are fan-shaped having an approximate shape of a quarter circle with the corner of the light emitting element or the corner of the opening in the second recess as the center. The insulating member is exposed. Thereby, the conductor wiring 11a is formed in the side surface direction of the light emitting element.
b and 11b are arranged. Therefore, light from the light emitting element is less absorbed by the exposed insulating member, and the light extraction efficiency of the light emitting device can be improved.

FIG. 4 is a plan view of a light emitting device in which the light emitting element 14 and the protection element 15 are mounted on the package 10 shown in FIG. FIG. 5 is a perspective view of a light emitting device in which a sealing resin 17 is formed on the package 10 shown in FIG.

The light emitting element 14 in the present embodiment has electrodes having different polarities on the upper surface and the lower surface. As shown in FIG. 4, the upper surface electrode of the light emitting element 14 is connected via a plurality of wires 16 to the conductor wiring 11 b disposed on the upper surface of the side wall forming the second recess. . These wires 16 are wire-bonded to different portions of the upper surface electrode of the light-emitting element 14 and are extended from the wire-bonded portions to different portions of the L-shaped pattern-shaped conductor wiring 11b. Yes. In this embodiment, wire bonding is performed so that the extending directions of the plurality of wires are substantially perpendicular. By making the wire bonding directions different in this way, for example, the influence of the sealing resin on the wire can be dispersed in each direction. That is, even if a wire stretched in one direction receives stress due to the sealing resin, a wire stretched in another direction does not always receive the same amount of stress. Therefore, it is possible to reduce the probability of occurrence of electrical connection failure due to wire breakage and to obtain a highly reliable light-emitting device.

FIG. 6 is a plan view showing the semiconductor device according to this embodiment. FIG. 7 is a vertical cross-sectional view taken along the line VII-VII shown in FIG. 6 for the semiconductor device of this example.

As shown in FIGS. 6 and 7, the light emitting device of this example is substantially the same as that of Example 1 except that exposed portions 18 are formed at positions corresponding to the respective sides of the outer shape of the light emitting element 14. This is the same as the light emitting device.

In addition, this exposed part 18 removes a part of conductor wiring 11aa in the light-emitting device of Example 1 in the part facing the center part of each side which comprises the external shape of the light emitting element 14, and the insulating layer 10 is removed.
It is formed by exposing e.

By providing the exposed portion 18 in this way, it is possible to suppress the flow of the bonding member when the light emitting element 14 is bonded to the conductor wiring 11a.

The semiconductor device of the present invention is not only an illumination device used for an image reading device in various devices equipped with semiconductor elements, specifically, facsimiles, copiers, hand scanners, etc., but also a light source for illumination and an LED display. When manufacturing semiconductor devices that can be used for various lighting devices such as backlight light sources such as mobile phones, traffic lights, illumination switches, in-vehicle stop lamps, various sensors and various indicators, It can be used simply and easily.

FIG. 1 is a plan view showing a package of a semiconductor device in one embodiment of the present invention. 2 is a vertical sectional view taken along the line II-II shown in FIG. FIG. 3 is a rear view showing the package of the semiconductor device in one embodiment of the present invention. FIG. 4 is a plan view of a semiconductor device in which a semiconductor element is mounted on the package shown in FIG. FIG. 5 is a perspective view of a semiconductor device in which a sealing resin is formed on the package shown in FIG. FIG. 6 is a plan view showing a semiconductor device according to another embodiment of the present invention. 7 is a vertical sectional view taken along line VII-VII shown in FIG. FIG. 8 is a cross-sectional view of a semiconductor device according to an embodiment of the present invention.

10 ... Package,
10a, 10b, 10c, 10d, 10e, 10f, 10g ... insulating layer,
11, 11aa, 11ab, 11b ... conductor wiring,
12 ... Thermally conductive member,
13 ... concave,
14: Light emitting element,
15 ... Protective element,
16 ... Wire,
17 ... sealing resin,
18 ... exposed part,
19: Support substrate,
20 ... bonding layer,
21... P-type semiconductor layer,
22 ... active layer,
23 ... n-type semiconductor layer,
24 ... n-side electrode,
25 ... eutectic material.

Claims (1)

A semiconductor light emitting device comprising: a semiconductor light emitting element; and a package having a recess that accommodates the semiconductor light emitting element, wherein a thermally conductive member is embedded in an insulating member constituting the package,
The upper and lower layers of the thermally conductive member are covered with an insulating member constituting the package,
An insulating member constituting the package is disposed outside the side surface of the thermally conductive member,
The side wall of the recess has a stepped portion between the outermost side wall forming the recess and the mounting portion of the semiconductor light emitting element provided on the bottom surface of the recess,
The thermally conductive member is extended from below the mounting portion to below the step portion,
The package has a conductor wiring for mounting a semiconductor light emitting element on the bottom surface of the recess,
And it has an external connection terminal formed continuously with the conductor wiring on the back,
The thermally conductive member is disposed so as to overlap below at least a part of the conductor wiring,
The semiconductor light emitting device, wherein the external connection terminal is disposed so as to overlap below at least a part of the thermally conductive member.

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