JP4552552B2 - Semiconductor device - Google Patents

Description

  The present invention relates to a surface-mount type semiconductor device in which electrodes are provided at both ends of a substrate.

  A surface-mount type semiconductor device has a semiconductor element mounted on a substrate and a pair of electrodes provided at both ends of the substrate. This semiconductor device is provided with a resist film between the electrodes on the mounting surface side so that the electrodes formed at both ends of the mounting surface of the substrate are not short-circuited by solder or the like when mounted on another substrate in the reflow process. It has been.

  A conventional semiconductor device is shown in FIG. FIG. 2A is a diagram on the mounting surface side of a semiconductor element of a conventional semiconductor device, and FIG. 2B is a diagram on the mounting surface side.

  As shown in FIG. 2A and FIG. 2B, the conventional semiconductor device 10 includes a light emitting diode 11 mounted on a substrate 12 and cross-sections formed at both end portions on the mounting surface side of the substrate 12. A resist film 16 is provided so as to overlap the two protruding portions 15 of the letter-shaped electrodes 13 and 14. Providing the resist film 16 in this way prevents solder from adhering so as to short-circuit the electrodes 13 and 14 when mounted on another substrate. In the illustrated example, the outer shape of the resist film 16 is formed to resemble the circuit symbol of the diode so that the polarity of the component can be easily determined.

  FIG. 3 shows another conventional semiconductor device. FIG. 3 is a bottom view of another conventional semiconductor device.

As shown in FIG. 3, another conventional semiconductor device 20 overlaps the electrode 23 so as not to overlap the substantially T-shaped electrodes 22 formed at both ends on the mounting surface side of the substrate 21. Thus, a resist film 24 is provided. By making the outer shape of the resist film 24 different between the electrode 22 side and the electrode 23 side, the polarity of this conventional semiconductor device is represented. A semiconductor device in which such a resist film is formed is described in Patent Document 1.
JP 2001-352102 A

  However, the conventional semiconductor device shown in FIGS. 2A and 2B is subjected to a stress that causes the substrate 12 to be bent in the process of mounting on another substrate, and cracks in the short direction of the substrate 12. May occur or the wiring pattern formed on the substrate 12 may be peeled off. This is because the strength of the substrate 12 cannot withstand the bending of the substrate 12. On the mounting surface side of the substrate 12 of the conventional semiconductor device 10 shown in FIG. 2 (b), an electrode 13 and an electrode 14, which are considered to have an effect of suppressing the bending of the substrate 12 in the longitudinal direction, 14 is provided with a resist film 16 that connects each of the projecting portions 15, but this is still insufficient to prevent cracking of the substrate 12 and peeling of the wiring pattern.

  Since the resist film 24 of the semiconductor device 20 described in Patent Document 1 shown in FIG. 3 overlaps the electrode 23 but does not overlap the electrode 22, the strength against bending of the substrate 21 in the longitudinal direction is as shown in FIG. It seems to be weaker than the conventional semiconductor device shown in FIG.

  In this way, when a conventional semiconductor device is mounted on another substrate, if the substrate is cracked or the wiring pattern is peeled off, the semiconductor element may not operate normally, so the semiconductor device is treated as a defective product. It will be. Although it is conceivable to employ a substrate having a high strength against the bending stress, the cost of the substrate increases.

  Accordingly, an object of the present invention is to provide a semiconductor device capable of suppressing the occurrence of defects by improving the flexural strength of the substrate without increasing the cost of the substrate.

  The present invention provides a surface-mount type semiconductor device in which a semiconductor element is mounted on a rectangular substrate, and the semiconductor element is mounted on a pair of electrodes having a U-shaped cross section at both ends of the substrate. And a resist film formed on the opposite surface of the mounting surface so that both ends overlap the pair of electrodes, and the width of the surface where the electrodes and the resist film overlap each other is It is characterized by being substantially equal to the width.

  A semiconductor device of the present invention is a surface-mount type semiconductor device in which a semiconductor element is mounted on a rectangular substrate, and a pair of electrodes having a U-shaped cross section at both ends of the substrate, and a semiconductor element And a resist film formed on the opposite surface of the mounting surface so that both ends overlap the pair of electrodes, and the width of the surface where the electrodes and the resist film overlap is defined as the width of the substrate. Since the resist film is formed so as to reinforce one side surface of the substrate, the strength against bending of the substrate is increased. Therefore, it is possible to suppress the occurrence of defects.

  Moreover, since this resist film only changes the external shape of the resist film formed in the conventional semiconductor device, it is not necessary to change the manufacturing process. Therefore, measures can be taken without increasing the cost.

  According to a first aspect of the present invention, in a surface-mount type semiconductor device in which a semiconductor element is mounted on a rectangular substrate, a pair of electrodes having a U-shaped cross section at both ends of the substrate, and the semiconductor element And a resist film formed so that both ends overlap a pair of electrodes on the opposite surface of the mounting surface, and the width of the surface where the electrode and the resist film overlap is defined as the width of the substrate. It is characterized by being substantially equal.

  Since the resist film is connected so that both ends overlap with a pair of electrodes formed on both ends of the substrate, the same effect can be obtained as when the thickness of the substrate is increased by the resist film.

  Further, if there is a concave portion such that the width of the resist film 16 gradually becomes narrower like the resist film 16 of the conventional semiconductor device shown in FIG. 2B, the resist film 16 against the bending stress. Only the width of the narrowest part of the substrate can be reinforced. Since both ends of the substrate where no electrode is formed have no reinforcement against bending, the substrate is easily cracked or the wiring pattern is peeled off. The resist film of the semiconductor light emitting device of the present invention has a rectangular outer shape, and the width of the surface where the electrode and the resist film overlap is substantially equal to the width of the substrate. Therefore, in order to reinforce both side portions where the electrode is not formed, the outer shape of the resist film is rectangular, and the width of the surface where the electrode and the resist film overlap is substantially equal to the width of the substrate, thereby forming the electrode. It is possible to reinforce the ends that are not formed.

  In addition, since the electrodes are formed in a U-shaped cross section at both ends of the rectangular substrate, and the resist film is formed so as to overlap the electrodes at both ends, the mounting surface that is the formation surface of the resist film The resist film is repelled by pulling the pair of electrodes against the warping. Accordingly, the strength against bending of the substrate is increased.

  Moreover, since this resist film only changes the external shape of the resist film formed in the conventional semiconductor device, it is not necessary to change the manufacturing process.

  The second invention of the present application is characterized in that an exposed portion is formed in the central portion of the resist film so that the substrate is exposed. Even if the resist film is formed so that the substrate is exposed at the portion, the bending strength can be secured by the resist film excluding the exposed portion. Further, the amount of resin for forming the resist film can be saved.

  A configuration of a semiconductor device according to an embodiment of the present invention will be described with reference to FIG. 1 by taking a semiconductor light emitting device as an example. 1A and 1B are diagrams illustrating a configuration of a semiconductor device according to an embodiment of the present invention, in which FIG. 1A is a front sectional view, FIG. 1B is a plan view, and FIG.

  As shown in FIG. 1, a semiconductor light emitting device 1 which is an example of a semiconductor device according to an embodiment of the present invention is a surface mount type, and includes a substrate 2 formed in a rectangular shape, a semiconductor light emitting element 3, and a pair. Electrodes 4 and 5 and a resist film 6.

  On the substrate 2, wiring patterns 7 and 8 are formed on the mounting surface of the semiconductor element 3. The wiring pattern 7 is electrically connected to the semiconductor light emitting element 3 and connected to the electrode 4, thereby electrically connecting the semiconductor light emitting element 3 and the electrode 4. The wiring pattern 8 is connected to the semiconductor light emitting element 3 via the wire 9 and is connected to the electrode 5, thereby electrically connecting the semiconductor light emitting element 3 and the electrode 5.

  The semiconductor light emitting element 3 is sealed with a resin mold 17.

  The electrodes 4 and 5 are formed at both ends of the substrate 2. The electrodes 4 and 5 are formed in a U-shaped cross section so as to be connected to an electrode provided on a mounting substrate which is another substrate and to be electrically connected to the semiconductor light emitting element 3. The widths of the electrodes 4 and 5 are formed to be equal to the width of the substrate 2 in the short direction. This is because, when the semiconductor light emitting device 1 is manufactured, after forming electrodes on a substrate on which a plurality of semiconductor light emitting elements are mounted in a row, the substrate is cut into individual semiconductor light emitting devices.

  The resist film 6 is formed on a mounting surface that is opposite to the mounting surface of the semiconductor light emitting element 3. This resist film 6 can provide the same effect as increasing the thickness of the substrate 2.

  The resist film 6 has a rectangular outer shape, and the width of the overlapping surface of the electrodes 4 and 5 and the resist film 6 is substantially equal to the width of the substrate. Since both ends 2a and 2b of the substrate 2 where the electrodes 4 and 5 are not formed have no reinforcement against bending, the cracks of the substrate 2 and the wiring patterns 7 and 8 are easily peeled off. Therefore, in order to reinforce both end portions where the electrodes 4 and 5 are not formed, the outer shape of the resist film 6 is rectangular, and the width of the surface where the electrodes 4 and 5 and the resist film 6 overlap is the width of the substrate 2. By making them substantially equal, both end sides 2a and 2b where the electrodes 4 and 5 are not formed can be reinforced.

  Further, the electrodes 4 and 5 are formed in a U-shaped cross section at both ends of the substrate 2 formed in a rectangular shape, and the resist film 6 is formed so as to overlap the electrodes 4 and 5 at both ends. The resist film 6 is repelled by pulling the pair of electrodes 4 and 5 with respect to the bending of the mounting surface on which the film 6 is formed. Accordingly, the strength against bending of the substrate 2 is increased.

  The resist film 6 is provided with an exposed portion 18 where the substrate 2 is exposed in a triangular shape at the center. By making the exposed portion 18 triangular, the direction of the anode side or the cathode side of the electrodes 4 and 5 of the semiconductor light emitting device 1 can be expressed. Further, the resin for forming the resist film 6 can be saved.

  Since the exposed portion 18 is formed in the central portion of the substrate 2, it does not affect the rectangular shape of the outer shape in order to reinforce both end portions where the electrodes are not formed. Therefore, the bending strength can be secured by the resist film 6 excluding the exposed portion 18. Further, the amount of resin for forming the resist film 6 can be saved. In the present embodiment, the exposed portion 18 has a triangular shape, but may have a rectangular shape, a polygonal shape, or an irregular shape.

  The resist film 6 is manufactured by changing the outer shape of the resist film 16 formed on the semiconductor device shown in FIG. 2 and the resist film 24 of the semiconductor device shown in FIG. There is no need to change the process. Therefore, measures can be taken without increasing the cost.

  Since the present invention can suppress the occurrence of defects by improving the flexural strength of the substrate, it is suitable for a surface mount type semiconductor device in which electrodes are provided at both ends of the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the structure of the semiconductor device which concerns on embodiment of this invention, (a) is front sectional drawing, (b) is a top view, (c) is a bottom view. (A) is the figure of the mounting surface side of the semiconductor element of the conventional semiconductor device, (b) is the figure of the mounting surface side. Bottom view of another conventional semiconductor device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor light-emitting device 2 Board | substrate 3 Semiconductor light-emitting element 4,5 Electrode 6 Resist film 7, 8 Wiring pattern 9 Wire 17 Resin mold 18 Exposed part

Claims (1)

In a surface mount type semiconductor device in which a semiconductor element is mounted on a rectangular substrate,
A pair of electrodes having a U-shaped cross section at both ends in the longitudinal direction of the substrate and having a width equal to the width in the short direction of the substrate, and a rectangular outer shape on the opposite surface of the mounting surface on which the semiconductor element is mounted. and a resist film formed to both end portions overlaps the pair of electrodes in shape, the lateral direction of the width of the substrate overlaps the surface of the electrode and the resist film, the lateral direction of the substrate A semiconductor device characterized in that an exposed portion is formed so as to be substantially equal to the width and to expose the substrate at a central portion of the resist film .

Images