JP2010238833A - Package for optical semiconductor device, and optical semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the occurrence of air bubbles or unfilled parts in a resin, thereby improving the accuracy of forming the resin, even if an optical semiconductor device is miniaturized and thinned. <P>SOLUTION: Each groove 10 is provided so as to connect each through-hole 9 formed in a half-etched region 8 on the backside of a lead frame 2 with the half-etched region. Consequently, it is possible to improve the accuracy of forming the resin, even if the optical semiconductor device is miniaturized and thinned. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical semiconductor device package in which a lead frame is sealed with a resin and an optical semiconductor device using the same.

  An optical semiconductor device is formed by mounting an optical semiconductor element in a package for an optical semiconductor device, and sealing the optical semiconductor element with a light-transmitting resin after electrical connection between the optical semiconductor element and the optical semiconductor device package. Is done. Further, the conventional package for optical semiconductor devices includes a reflector for improving the light emission efficiency around the optical semiconductor element mounting region in the lead frame, and in order to hold the reflector formed of resin on the lead frame, Resin is also formed on the back surface of the lead frame with respect to the optical semiconductor element mounting surface.

  On the other hand, as one of the methods to reduce the height of the package for optical semiconductor devices, it is required to thin the resin on the back surface of the lead frame. A structure is used in which the frame is thinned and a resin is formed only in the thinned half-etched region.

Hereinafter, the configuration of a conventional package for an optical semiconductor device will be described with reference to FIG.
FIG. 7 is a view showing the structure of a conventional package for an optical semiconductor device, FIG. 7 (a) is a view showing a back surface with respect to the chip mounting surface, and FIG. 7 (b) is a cross-sectional view taken along line EE in FIG. FIG. 7C is a view showing the back surface of the lead frame.

  In FIG. 7, a conventional optical semiconductor device package 71 has a structure in which a resin 73 is formed on a lead frame 72, and a die pad 75 surrounded by a reflector 74 made of the resin 73 and a surface on which the die pad 75 is formed ( Hereinafter, the external terminal 76 exposed on the back surface with respect to the front surface) is provided. The external terminal 76 is exposed on the back surface of the lead frame 72 and functions as a surface mounting terminal when mounted on the substrate. Further, the heat radiation area 77 is also exposed on the back surface of the lead frame 72, and a low profile and high heat radiation efficiency structure is realized without attaching a heat sink or the like.

On the back surface of the lead frame 72, a half-etched region 78 is formed in a region excluding the external terminal 76 and the heat dissipation region 77, and the resin 73 is formed only inside the half-etched region 78. The surface of the resin 73 is configured to be substantially flush with the lead frame 72.
JP 2005-79372 A

  In the conventional package 71 for optical semiconductor devices, when the resin 73 is formed, the resin is supplied from the lead frame surface side, and the resin 73 is formed in the half-etched region 78 through the holes 81 and the slits 82.

  However, the structure of the conventional package 71 for optical semiconductor devices has a problem that bubbles may be formed in the resin 73 at the junction of the resin 73 supplied from the plurality of holes 81. Further, depending on the shape of the half-etched region 78, there is a problem that the resin 73 does not sufficiently wrap around and a region where the resin 73 is not filled may occur. In particular, unfilled resin 73 is likely to occur at the corners in the half-etched region 78 shape.

  Further, as a problem peculiar to the package for an optical semiconductor device, it is necessary to provide a hollow portion surrounded by a reflector 74 made of a resin 73 for accommodating an optical semiconductor element and exposing the die pad 75 on the bottom surface. Existence is a more disadvantageous factor for the above problems.

  In order to solve the above problems, an optical semiconductor device package and an optical semiconductor device according to the present invention are small and thin optical semiconductor devices that suppress the generation of bubbles and unfilled portions formed in a resin. Even if it exists, it aims at providing what can manufacture by improving the formation precision of resin, without being restrict | limited to the form.

  In order to achieve the above object, a package for an optical semiconductor device according to the present invention includes a lead frame including a die pad and an external terminal, and a thickness of the lead frame on a back surface of the lead frame with respect to a surface on which the die pad is formed. A plurality of half-etched regions formed in the lead frame, a plurality of holes for resin supply formed through the lead frame from the surface on which the die pad is formed to the back surface, and the die pad formed in the half-etched region One or a plurality of through holes formed penetrating to the surface to be formed, one or a plurality of grooves formed between the half-etched regions, a resin formed around the die pad and in the half-etched regions It is characterized by having.

  A lead frame including a die pad and two external terminals; a plurality of half-etched regions formed by reducing the thickness of the lead frame on a back surface of the lead frame with respect to a surface on which the die pad is formed; and the lead frame A plurality of holes for resin supply formed through the surface from the surface where the die pad is formed to the back surface, and one or a plurality of holes formed through the surface where the die pad is formed in the half-etched region The two external terminals having a through hole, one or a plurality of grooves formed between the half-etched regions, a resin formed in the periphery of the die pad and in the half-etched region, and exposed on the back surface The areas are substantially the same.

In addition, some of the through holes are formed between the two holes.
Further, some of the through holes are formed in the vicinity of a corner portion of a surface shape formed by the half-etched region.

In addition, a portion having a thin thickness in a direction perpendicular to a surface on which the die pad is formed is formed on an outer peripheral portion of the resin formed around the die pad.
Further, the thickness of the resin around the die pad or the resin in the thin portion is 0.3 mm or less.

  Further, a notch is formed in a corner portion forming the outer periphery of the lead frame of the external terminal exposed on the back surface, and surface treatment is performed on the external terminal exposed on the back surface and the cut surface. Features.

  Further, a recess is formed in the side surface of the lead frame where the lead frame is recessed in the die pad direction, and surface treatment is performed on the external terminal exposed on the back surface and the side surface of the recess continuous from the external terminal. It is characterized by giving.

  Furthermore, the optical semiconductor device of the present invention includes the optical semiconductor device package, an optical semiconductor element mounted on the die pad, a wire for electrically connecting the optical semiconductor element and the external terminal, and the die pad. It has translucent resin which seals the resin formed in circumference | surroundings including the said optical semiconductor element, It is characterized by the above-mentioned.

  As described above, even if the optical semiconductor device is reduced in size and thickness, the resin formation accuracy can be improved.

  As described above, the package for an optical semiconductor device and the optical semiconductor device of the present invention include a through hole formed in the half-etched region on the back surface of the lead frame and a groove connecting the half-etched region, thereby reducing the size and thickness. Even an optical semiconductor device can be improved in resin formation accuracy, and can be manufactured without being restricted by its form.

(Embodiment 1)
First, the package for an optical semiconductor device according to the first embodiment will be described with reference to FIG.

  1A and 1B are diagrams showing the structure of an optical semiconductor device package according to the first embodiment. FIG. 1A is a diagram showing a back surface with respect to a chip mounting surface, and FIG. FIG. 1A is a cross-sectional view of the lead frame, and FIG.

  In FIG. 1, an optical semiconductor device package 1 of the present invention has a structure in which a thermosetting resin 3 such as epoxy or silicon is formed on a lead frame 2, and a die pad surrounded by a reflector 4 made of the resin 3. 5 and an external terminal 6 exposed on the back surface with respect to the surface on which the die pad 5 is formed (hereinafter referred to as the front surface). The external terminal 6 is exposed on the back surface of the lead frame 2 and functions as a surface mounting terminal when mounted on the substrate. Here, FIG. 1 shows an example in which two external terminals 6 are provided, but the number of terminals is arbitrary, and the present invention can be applied to devices other than optical semiconductor devices.

  On the back surface of the lead frame 2, a half-etched region 8 is formed in a region excluding the external terminal 6 and the heat dissipation region 7, and the resin 3 is formed only inside the half-etched region 8. The surface of the resin 3 is formed so as to be substantially flush with the lead frame 2.

  The optical semiconductor device package of the present invention is characterized in that a through hole 9 reaching the surface of the lead frame 2 and a groove 10 formed between adjacent half etching regions 8 are formed in the half etching region 8. By forming the through hole 9 and the groove 10 as described above, bubbles generated at the joining point of the resin 3 flowing in different flow paths, unfilling of the resin 3 caused by the shape of the half-etching region 8 and the like are prevented. be able to.

  For example, as shown in FIG. 1C, the lead frame 2 is provided with an external terminal 6 a and an external terminal 6 b as the heat dissipation area 7 and the external terminal 6. Further, holes 11 for supplying resin from the surface of the lead frame 2 are formed around these. In addition, a slit 12 is formed in order to make the external terminal 6b electrically independent. At the time of resin formation, the resin 3 supplied from the front surface of the lead frame 2 wraps around the back surface of the lead frame 2 from these holes 11, slits 12, etc., and forms the resin 3 in the half-etched region 8. At this time, bubbles are easily formed in the resin 3 in the region 13 where the resin 3 supplied from different holes 11 merges. Further, depending on the shape of the external terminal 6, there is a portion where it is difficult for the resin 3 to wrap around like the region 14, and the resin 3 may not be filled at the corners of the region 14. Therefore, in order to prevent generation of bubbles and unfilling of the resin 3, the through holes 9 are provided in the vicinity of the regions 13 and 14. Furthermore, by providing a groove 10 that connects the half-etched region 8 formed around the external terminal 6a and the half-etched region 8 formed around the external terminal 6b, the resin 3 can be more easily distributed and downsized. , Even in the thinned optical semiconductor device, the formation accuracy of the resin 3 is improved.

  Further, by forming the through holes 9 and the grooves 10 in the contact surface with the resin 3 on the back surface of the lead frame 2, the contact area between the resin 3 and the lead frame 2 is increased, and the adhesion of the resin 3 is improved. Therefore, it is possible to prevent the lead from being removed and the resin 3 from being peeled off, and to prevent leakage of the translucent resin to be formed later.

Here, it is desirable that the thickness of the resin 3 formed on the surface on which the die pad 5 is formed be 0.3 mm or less. Thus, by reducing the thickness of the resin 3 formed on the surface on which the die pad 5 is formed, the difference in thermal expansion coefficient can be reduced, and the warpage of the lead frame 2 can be suppressed.
(Embodiment 2)
Next, an optical semiconductor device package according to the second embodiment will be described with reference to FIG.

  FIG. 2 is a diagram showing the structure of the lead frame in the second embodiment, and shows the back surface with respect to the die pad region. The package for the optical semiconductor device of the present embodiment is formed by sealing the lead frame with resin.

In the lead frame 2 in the first embodiment, the areas of the external terminals 6a and the external terminals 6b (see FIG. 1) are different. In the optical semiconductor device package of the second embodiment, the area of the external terminal 26a and the external terminal 26b of the lead frame 22 is made the same as that of the lead frame in the first embodiment, as shown in FIG. When the areas of the external terminal 26a and the external terminal 26b are different, the stress applied to the external terminal 26a and the external terminal 26b varies when the optical semiconductor device is mounted on the substrate, so that one of the external terminals rises due to the difference in adhesive force. It will be. By making the area of the external terminal 26a and the external terminal 26b the same, the stress does not vary, and the resin formation accuracy can be improved while suppressing the rising of the external terminal. Here, the same area does not require that the areas completely coincide with each other, but includes a substantially coincident range in which variations in stress fall within an allowable range.
(Embodiment 3)
Next, the package for an optical semiconductor device according to the third embodiment will be described with reference to FIG.

FIG. 3 is a cross-sectional view showing the structure of the optical semiconductor device package in the third embodiment.
In the package for optical semiconductor devices according to the first and second embodiments, as shown in FIG. 3, a step is provided in the outer peripheral portion of the reflector to reduce the thickness of the outer peripheral portion of the reflector. By reducing the thickness of the outer peripheral portion like the reflector 34, the thickness of the resin 33 formed on the lead frame 32 can be partially reduced, so that the difference in thermal expansion coefficient can be alleviated. The resin formation accuracy can be improved while suppressing the warpage of 32. Here, it is preferable that the thickness of the portion of the resin 33 in which the thickness of the outer peripheral portion is reduced is 0.3 mm or less.
(Embodiment 4)
Next, the package for an optical semiconductor device according to the fourth embodiment will be described with reference to FIGS.

  4A and 4B are diagrams showing the structure of the package for an optical semiconductor device according to the fourth embodiment. FIG. 4A is a diagram showing the back surface with respect to the chip mounting surface, and FIG. It is B sectional drawing. FIG. 5 is a view showing the structure of an optical semiconductor device package in which a recess is formed in a part of the external terminal according to the fourth embodiment. FIG. 5 (a) is a view showing the back surface with respect to the chip mounting surface, and FIG. These are CC sectional drawing of Fig.5 (a).

The present embodiment is characterized in that in the package for an optical semiconductor device described in any of Embodiments 1 to 3, a notch or a recess is formed in a corner portion serving as a mounting surface of an external terminal.
For example, as shown in FIG. 4, a notch 47 is provided in the corner portion of the outer peripheral portion of the exposed surface of the external terminal 46a and the external terminal 46b over the entire side where the corner portion is formed. Then, the cross section of the notch 47 is stepped as shown in FIG. Alternatively, as shown in FIG. 5, a concave portion 57 in which a part of the side surface is recessed is provided in a region where the external terminal 56 a and the external terminal 56 b are formed on the side surface of the lead frame 52.

Further, the bottom surface and the side surface of the notch 47 and the side surface of the recess 57 are plated on the surface in the same manner as the external terminal 46a, the external terminal 46b, the external terminal 56a, and the external terminal 56b.
In this way, a notch or a recess is provided in the external terminal, and the notch or the recess is subjected to a surface treatment in a state where it is connected to the adjacent lead frame on the side surface other than the notch or the recess, whereby the optical semiconductor device is mounted on the substrate. In this case, the wet spreading area when soldering is increased, and it can be easily recognized that there is no problem in solder mounting. Further, since the mounting area is increased, the fixing strength at the time of mounting is improved. Therefore, with the optical semiconductor device package of the fourth embodiment, it is possible to improve the solder mounting inspection visibility and mounting strength while improving the resin formation accuracy.
(Embodiment 5)
Next, the optical semiconductor device according to the fifth embodiment will be described with reference to FIG.

6A and 6B are views showing the structure of the semiconductor device of the present invention. FIG. 6A is a view showing an optical semiconductor element mounting surface, and FIG. 6B is a cross-sectional view taken along the line DD in FIG. .
FIG. 6 shows an optical semiconductor device in which the optical semiconductor element 60 is mounted on the optical semiconductor device package shown in FIG. 4, but the optical semiconductor device package shown in the first to fourth embodiments has an optical signal. The same applies to an optical semiconductor device in which the semiconductor element 60 is mounted.

  As shown in FIG. 6, in the optical semiconductor device of the present invention, the optical semiconductor element 60 is mounted on the die pad 65 of the package for the optical semiconductor device, and the optical semiconductor element 60, the external electrode 66a, and the external electrode 66b are respectively connected to the wire 61. Are electrically connected. Further, the reflector 64 is sealed with a translucent resin 62 in a state where the optical semiconductor element 60 is mounted.

As described above, since the optical semiconductor device is formed using the optical semiconductor device package described in Embodiments 1 to 4, the resin formation accuracy can be improved.
In each of the above embodiments, the number and shape of the through holes are arbitrary, and may be circular, elliptical, or track-shaped. Moreover, it can also be made into a slit shape. Similarly, the number and shape of the grooves are arbitrary.

  INDUSTRIAL APPLICABILITY The present invention can improve resin formation accuracy, and is useful for an optical semiconductor device package in which a lead frame is sealed with a resin, an optical semiconductor device using the same, and the like.

The figure which shows the structure of the package for optical semiconductor devices in Embodiment 1 The figure which shows the structure of the lead frame in Embodiment 2. Sectional drawing which shows the structure of the package for optical semiconductor devices in Embodiment 3 The figure which shows the structure of the package for optical semiconductor devices in Embodiment 4 The figure which shows the structure of the package for optical semiconductor devices which provides a recessed part in a part of external terminal in Embodiment 4 The figure which shows the structure of the semiconductor device of this invention The figure which shows the structure of the conventional package for optical semiconductor devices

DESCRIPTION OF SYMBOLS 1 Package for optical semiconductor devices 2 Lead frame 3 Resin 4 Reflector 5 Die pad 6 External terminal 6a External terminal 6b External terminal 7 Heat dissipation area 8 Half-etched area 9 Through hole 10 Groove 11 Hole 12 Slit 13 Area 14 Area 22 Lead frame 26a External terminal 26b External terminal 32 Lead frame 33 Resin 46a External terminal 46b External terminal 47 Notch 52 Lead frame 56a External terminal 56b External terminal 57 Recess 34 Reflector 60 Optical semiconductor element 61 Wire 62 Translucent resin 66a External terminal 66b External terminal 71 Optical semiconductor Device Package 72 Lead Frame 73 Resin 74 Reflector 75 Die Pad 76 External Terminal 77 Heat Dissipation Area 78 Half Etch Area 81 Hole 82 Slit

Claims (9)

A lead frame comprising a die pad and external terminals;
A plurality of half-etched regions formed by reducing the thickness of the lead frame on the back surface of the lead frame with respect to the surface on which the die pad is formed;
A plurality of holes for resin supply formed through the lead frame from the surface on which the die pad is formed to the back surface;
One or more through holes formed through the half-etched region up to the surface on which the die pad is formed;
One or more grooves formed between the half-etched regions;
A package for an optical semiconductor device, comprising: a resin formed in a periphery of the die pad and in the half-etched region. A lead frame comprising a die pad and two external terminals;
A plurality of half-etched regions formed by reducing the thickness of the lead frame on the back surface of the lead frame with respect to the surface on which the die pad is formed;
A plurality of holes for resin supply formed through the lead frame from the surface on which the die pad is formed to the back surface;
One or more through holes formed through the half-etched region up to the surface on which the die pad is formed;
One or more grooves formed between the half-etched regions;
2. The optical semiconductor device according to claim 1, further comprising: a resin formed in a periphery of the die pad and in the half-etched region, wherein the areas of the two external terminals exposed on the back surface are substantially the same. For package.   The optical semiconductor device package according to claim 1, wherein some of the through holes are formed between the two holes.   4. The optical semiconductor device according to claim 1, wherein some of the through holes are formed in the vicinity of a corner portion of a surface shape formed by the half-etched region. 5. package.   The light according to any one of claims 1 to 4, wherein a portion having a thin thickness in a direction perpendicular to a surface on which the die pad is formed is formed on an outer peripheral portion of the resin formed around the die pad. Package for semiconductor devices.   6. The package for an optical semiconductor device according to claim 1, wherein a thickness of a resin around the die pad or a resin in the thin portion is 0.3 mm or less.   A notch is formed in a corner portion forming the outer periphery of the lead frame of the external terminal exposed on the back surface, and the external terminal exposed on the back surface and the cut surface are subjected to surface treatment. The package for optical semiconductor devices according to any one of claims 1 to 6.   A recess is formed in a part of the side surface of the lead frame so that the lead frame is recessed in the die pad direction, and surface treatment is performed on the external terminal exposed on the back surface and the side surface of the recess continuous from the external terminal. The package for an optical semiconductor device according to claim 1, wherein: The package for optical semiconductor devices according to any one of claims 1 to 8,
An optical semiconductor element mounted on the die pad;
A wire for electrically connecting the optical semiconductor element and the external terminal;
An optical semiconductor device comprising: a translucent resin that seals the resin formed around the die pad including the optical semiconductor element.

Images