JP2007180275A - Optical semiconductor device and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical semiconductor device which is high in both coupling efficiency and optical transmission quality, excellent in environmental resistant-properties, shows its high reliability, moreover is capable of utilizing a small optical semiconductor element, such as an LED, a PD, etc, simple in structure, and capable of satisfying requirements, such as a size reduction and a cost reduction, at the same time. <P>SOLUTION: The optical semiconductor device is equipped with a lead frame 4, an optical semiconductor element 3 mounted on the lead frame 4, an auxiliary frame 8 which is arranged along the lead frame 4 separating from the optical semiconductor element 3 by a prescribed clearance, a buffer resin 7 formed of translucent resin and provided for covering the outer surface of the optical semiconductor element 3, and a molding resin 11 formed of translucent resin. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor device in which an optical semiconductor element is sealed with a mold resin, and is typically used for an optical communication device that transmits and receives an optical signal using an optical transmission medium such as an optical fiber. It is related with the optical semiconductor device which can do.

  The present invention also relates to an electronic apparatus provided with such an optical semiconductor device. Here, the electronic devices include digital TV (Television), digital BS (Broadcasting Satellite) tuner, CS (Communication Satellite) tuner, DVD (Digital Versatile Disc: Digital Versatile Disc) Disc) player, CD (Compact Disc) player, AV (Audio Visual) amplifier, audio, personal computer (hereinafter referred to as personal computer), personal computer peripheral device, mobile phone, PDA (Personal Digital Assistant: Personal digital assistant). Also included are environments with a wide operating temperature range, for example, car audio and car navigation systems that are in-vehicle devices, robot sensors in a factory, control devices, and the like.

  2. Description of the Related Art Conventionally, an optical semiconductor device that couples an optical semiconductor element such as a light emitting diode (LED) or a photodiode (PD) with an optical fiber has been known. It is used for optical communication.

  As these optical semiconductor devices, those manufactured by using transfer molding of a light-transmitting resin as shown in FIG. 14 are widely used. In the optical semiconductor device 101 shown in FIG. 14, an optical semiconductor element 103 disposed on a lead frame 104 is sealed with a translucent resin 110, and an optical semiconductor is formed by a lens 108 made of a part of the translucent resin 110. The element 103 and the optical fiber 102 are optically coupled. The optical semiconductor element 103 is electrically coupled to the lead frame 104 and the wire 105. In some cases, a semiconductor element for driving and controlling the optical semiconductor element 103 is mounted on the lead frame 104. Such an optical semiconductor device using transfer molding has a feature that it is inexpensive and easy to manufacture as compared with, for example, an optical semiconductor device using a glass lens.

  On the other hand, it is known that the coefficient of linear expansion and thermal conductivity can be adjusted by adding a filler to the resin mold material. For semiconductor elements that do not require optical properties, a mold resin with filler added (usually black) Is sealed. However, in the above-described optical semiconductor device 101 using the translucent resin 110, it is difficult to add a filler because the optical characteristics are important (or only a small amount can be added). There was a problem in the sex.

  For this reason, as shown in FIG. 15, an optical semiconductor device that can be sealed with a colored mold resin to which a filler is added has been proposed (for example, Patent Document 1 No. 2000-173947). In the optical semiconductor device 201 illustrated in FIG. 15, the optical semiconductor element 203 in which the glass lens 208 is attached only to the optical unit 206 is mounted on the lead frame 204. The electrodes around the optical unit 206 of the optical semiconductor element 203 and the lead frame 204 are electrically coupled by a wire 205. Thereafter, transfer molding is performed using a colored mold resin 209 to which a filler is added, so that the optical semiconductor element 203 and the wire 205 are not covered without covering the optical path (the top of the glass lens 208) through which light enters and exits the optical semiconductor element 203. Only the colored mold resin 209 is sealed.

  However, Patent Document 1 does not disclose specific means for performing transfer molding so as to obtain the structure shown in FIG. In general, a resin used for transfer molding has fine particles, and the resin leaks through a gap of several μm. For this reason, it is considered difficult to seal only the optical semiconductor element 203 and the wire 205 by transfer molding without covering the top of the glass lens 208. In addition, when using a relatively large (several mm square to several tens mm square) optical semiconductor element such as a CCD (Charge Coupled Device), a glass lens can be disposed in the optical section. However, since an optical part is very small in an optical semiconductor element having a small size (several hundred μm square) such as an LED, it is necessary to use a very small glass lens. (I) Optically It is difficult to design an effective lens, (ii) it is difficult to produce a small glass lens, and (iii) it is difficult to join and align the optical part and the glass lens. There is a problem that there is. Further, when a glass lens larger than the optical part of the optical semiconductor element is used, the glass lens is also bonded to the electrode close to the optical part of the optical semiconductor element, so that wire bonding cannot be performed.

  Patent Document 1 discloses a method of using a resin lens. However, when an optical semiconductor element having a small size, such as an LED, is used, the optical unit is small and it is difficult to cope with the same reason. Furthermore, when a resin lens is used, it is necessary to attach the resin lens after molding with a colored mold resin because of the problem of heat resistance of the lens. For this reason, it is necessary to hold the optical part of the optical semiconductor element and the mold with a pressure contact or a minute gap so that the colored resin does not enter the optical part of the optical semiconductor element. Manufacture is difficult because mold management (and prevention of lead frame deformation) is required. In particular, in an optical semiconductor element having a small size such as an LED, it is very difficult to manage the colored mold resin so as not to enter the optical part while protecting the wire.

  In general, there is a relatively large difference between the linear expansion coefficient of the translucent mold resin and the linear expansion coefficients of the optical semiconductor element, the lead frame, and the bonding wire. For this reason, in the conventional optical semiconductor device, there is a possibility that a disconnection of a bonding wire, a package crack, or the like may occur in a high operating temperature range.

  Furthermore, the heat conductivity of the translucent mold resin is about 0.17 W / m · K, which is much lower than that of metal (for example, the heat conductivity of copper material is 365 W / m · K). Small. For this reason, in the conventional optical semiconductor device, the heat generated in the optical semiconductor element is difficult to diffuse, and the operating range at a high temperature is limited.

  Further, an optical semiconductor device as shown in FIG. 16 has been proposed (see Patent Document 2 (Japanese Patent Application No. 2005-213184)). In this optical semiconductor device, optical semiconductor elements 302 and 305 are mounted on a lead frame 301, and one optical semiconductor element 302 is covered with a silicone resin 313. Further, the optical semiconductor element 302 covered with the silicone resin 313 and the other optical semiconductor element 305 are sealed with a light-transmitting mold resin portion 314, and the mold resin portion 314 is further provided with a light-transmitting property. The mold resin portion 315 is sealed. The linear expansion coefficient of the mold resin portion 314 is made smaller than the linear expansion coefficient of the mold resin portion 315.

  However, the optical semiconductor device of FIG. 16 has a problem that the application amount (thickness) of the silicone resin 313 covering the optical semiconductor element 302 varies in the manufacturing stage. When the application amount of the silicone resin 313 is small, the optical semiconductor element 302 directly contacts the mold resin 314, or the thickness of the portion of the mold resin 314 directly above the optical semiconductor element 302 increases. On the other hand, when the application amount of the silicone resin 313 is large, when the first and second transfer moldings are performed to provide the mold resin portions 314 and 315, the top portion of the silicone resin 313 comes into contact with the mold. For this reason, it is difficult to manufacture the optical semiconductor device of FIG. 16 according to the optical design. That is, it is difficult to obtain a desired shape, and variation in light coupling efficiency increases. Further, since the mold resin portions 314 and 315 of this optical semiconductor device do not have a shielding effect, in order to realize an optical semiconductor device with higher optical transmission quality (S / N ratio), the outer side of this optical semiconductor device is used. It is necessary to separately provide a shield plate or the like. This complicates the shield structure. Further, regarding heat dissipation, only heat dissipation by transmitting a lead frame on which a semiconductor element is mounted and a mold resin can be expected.

As described above, the conventional technology has not realized an optical semiconductor device that can realize high coupling efficiency and optical transmission quality with a simple configuration, and has excellent environmental resistance and high reliability.
JP 2000-173947 A Japanese Patent Application No. 2005-213184

  Therefore, the object of the present invention is to use an optical semiconductor device having high coupling efficiency and optical transmission quality, excellent environment resistance and high reliability, and an optical semiconductor element having a small size such as an LED or PD, An object of the present invention is to provide an optical semiconductor device that can achieve both downsizing and cost reduction with a simple configuration.

  Moreover, the subject of this invention is providing the electronic device provided with such an optical semiconductor device.

In order to solve the above problems, an optical semiconductor device of the present invention is
A lead frame,
An optical semiconductor element mounted on the lead frame;
An auxiliary frame disposed along the lead frame with a predetermined gap with respect to the optical semiconductor element;
A buffer resin portion made of a translucent resin provided between the lead frame and the auxiliary frame and covering an outer surface of the optical semiconductor element;
An optical semiconductor element covered with the buffer resin part; and a mold resin part made of a translucent resin that seals at least a part of the lead frame and the auxiliary frame along the optical semiconductor element. It is characterized by that.

  Here, the phrase “the auxiliary frame has a“ predetermined gap ”” with respect to the optical semiconductor element means that the auxiliary frame has a gap suitable for arranging, for example, wire wirings for the optical semiconductor element.

  In the optical semiconductor device of the present invention, since the mold resin portion and the buffer resin portion are each made of a translucent resin, the optical semiconductor element receives light from the outside through the mold resin portion and the buffer resin portion, or emits light to the outside. Can be issued.

  In this optical semiconductor device, an auxiliary frame is disposed along the lead frame with a predetermined gap with respect to the optical semiconductor element. Therefore, the heat generated by the optical semiconductor element can be released not only through the lead frame but also through the buffer resin portion and the auxiliary frame to the outside of the optical semiconductor device and diffused throughout the mold resin portion. . When heat diffuses over almost the entire mold resin portion, the heat easily diffuses from the mold resin portion to the outside (air). Therefore, it is possible to prevent the temperature from rising due to heat accumulation inside the optical semiconductor element serving as a heat source during operation. Therefore, an optical semiconductor device having excellent environmental resistance can be realized. In particular, even when an optical semiconductor element having a small chip size is used, the heat generated by the optical semiconductor element is diffused to almost the entire mold resin portion and released from almost the entire outer peripheral surface of the mold resin portion to the outside. can do. For example, when the optical semiconductor element is a light emitting element having a small chip size and generating heat locally, such as an LED, the effect of heat dissipation is increased.

  In addition, since the outer surface of the optical semiconductor element is covered with the buffer resin portion, the stress applied to the bonding wire for electrical connection to the optical semiconductor element and the outer surface of the optical semiconductor element can be reduced. Therefore, a highly reliable optical semiconductor device can be realized.

  The optical semiconductor device is configured to integrally seal the optical semiconductor element covered with the buffer resin portion and at least a portion of the lead frame and the auxiliary frame along the optical semiconductor element. It has a simple configuration. Therefore, both size reduction and price reduction can be achieved. Further, since a glass lens or the like is not mounted on the optical semiconductor element, a small-sized optical semiconductor element such as an LED or PD can be used.

  The lead frame and the auxiliary frame are preferably made of a member having good thermal conductivity, such as metal.

In the optical semiconductor device of one embodiment,
The optical semiconductor element has an optical part that receives or emits light on the surface opposite to the surface attached to the lead frame among the outer surfaces of the optical semiconductor element,
The auxiliary frame has a facing portion facing the header portion on which the optical semiconductor element of the lead frame is mounted, and an opening is provided in a portion corresponding to the optical portion of the facing portion. And

  In the optical semiconductor device of this embodiment, light can be received from the outside or emitted to the outside through the mold resin portion, the opening of the opposing portion of the auxiliary frame, and the buffer resin portion. That is, the optical part of the optical semiconductor element is not shielded by the opposing part of the auxiliary frame. Therefore, an optical semiconductor device having high coupling efficiency can be realized.

  In addition, in this optical semiconductor device, since the auxiliary frame has a facing portion facing the header portion on which the optical semiconductor element of the lead frame is mounted, the effect of heat dissipation is further increased. Therefore, it is possible to realize an optical semiconductor device having further excellent environmental resistance.

In the optical semiconductor device of one embodiment,
Inside the mold resin part, a core part made of a resin different from the translucent resin forming the mold resin part is provided,
The core portion integrally seals the optical semiconductor element covered with the buffer resin portion, the header portion of the lead frame, and the facing portion of the auxiliary frame, and corresponds to the opening of the facing portion. It has an opening at the site.

  In the optical semiconductor device of this embodiment, light can be received from the outside or emitted to the outside through the mold resin portion, the opening of the core portion, the opening of the opposing portion of the auxiliary frame, and the buffer resin portion. . That is, the optical part of the optical semiconductor element is not shielded by the resin forming the core part or the opposing part of the auxiliary frame. Therefore, an optical semiconductor device having high coupling efficiency can be realized.

  In addition, in this optical semiconductor device, the thermal expansion coefficient of the core portion is brought close to the thermal expansion coefficient of the lead frame, while the linear expansion coefficient of the resin forming the core portion and the translucent resin line forming the mold resin portion are used. It is possible to reduce the difference from the expansion coefficient. In such a case, the structure is less likely to cause package cracking due to thermal stress and bonding wire disconnection. Therefore, an optical semiconductor device with high reliability and good optical transmission quality can be realized.

In the optical semiconductor device of one embodiment,
A signal processing circuit mounted on the lead frame and processing the output of the optical semiconductor element;
The signal processing circuit is located between the lead frame and the auxiliary frame.

  According to the optical semiconductor device of this embodiment, since the signal processing circuit is located between the lead frame and the auxiliary frame, not only the lead frame but also the heat generated from the signal processing circuit It can be reliably removed via the auxiliary frame. Therefore, an optical semiconductor device with high reliability and good optical transmission quality can be realized.

  In an optical semiconductor device according to an embodiment, the optical semiconductor element and the signal processing circuit are included in one chip.

  According to the optical semiconductor device of this embodiment, since the optical semiconductor element and the signal processing circuit are integrated into one chip, a wire between the optical semiconductor element and the signal processing circuit becomes unnecessary. Therefore, the stray capacitance is reduced, enabling high-speed response and being less susceptible to electromagnetic noise. Further, since the number of chips is reduced, manufacturing is facilitated, and cost can be reduced.

  In the optical semiconductor device of one embodiment, the buffer resin portion is made of a silicone resin having translucency and cold resistance.

  In the optical semiconductor device of this embodiment, since the buffer resin portion is made of a silicone resin having translucency and cold resistance, stress applied to the bonding wire and the optical semiconductor element at a low temperature can be reduced. Therefore, an optical semiconductor device with higher reliability can be realized.

  In the optical semiconductor device of one embodiment, the buffer resin portion is made of an epoxy resin mixed with a transparent filler.

  In the optical semiconductor device of this embodiment, since the buffer resin portion is made of an epoxy resin mixed with a transparent filler, the stress applied to the bonding wire and the optical semiconductor element can be reduced. Therefore, an optical semiconductor device with higher reliability can be realized.

In the optical semiconductor device of one embodiment, the distance between the header portion of the lead frame and the opposing portion of the auxiliary frame is d, the height of the optical semiconductor element from the lead frame is H1, and the above When the height from the surface of the wire bonded to the surface of the optical semiconductor element is H2,
d> H1 + H2
The relationship is satisfied.

  In the optical semiconductor device according to this embodiment, since the above relationship is satisfied, the facing portion of the auxiliary frame does not contact the wire bonded to the surface of the optical semiconductor element. Therefore, a short circuit or the like due to wire deformation or contact does not occur, and an optical semiconductor device with higher reliability can be realized.

  The wire connects the surface of the optical semiconductor element and a lead terminal disposed around the header portion of the lead frame.

  In the optical semiconductor device of one embodiment, the translucent resin forming the buffer resin portion is filled in a gap between the header portion of the lead frame and the opposing portion of the auxiliary frame while covering the optical semiconductor element. It is characterized by.

  In the optical semiconductor device of this embodiment, since the translucent resin that forms the buffer resin portion is filled in a gap between the header portion of the lead frame and the opposing portion of the auxiliary frame, the auxiliary frame And the occurrence of peeling and cracks between the resin and the buffer resin portion are prevented. Therefore, an optical semiconductor device with higher reliability can be realized.

  In the optical semiconductor device of one embodiment, the auxiliary frame has conductivity.

  In the optical semiconductor device according to this embodiment, the auxiliary frame has a conductive effect, so that the auxiliary frame has a shielding effect on the optical semiconductor element. Therefore, an optical semiconductor device with good optical transmission quality can be realized.

  In the optical semiconductor device of one embodiment, a surface of the auxiliary frame that faces the optical semiconductor element has an insulating property.

  In the optical semiconductor device of this embodiment, since the surface of the auxiliary frame that faces the optical semiconductor element has an insulating property, even if the auxiliary frame and the wire are in contact with each other, there is a problem such as a short circuit. Does not happen. Therefore, an optical semiconductor device with higher reliability can be realized.

  In the optical semiconductor device of one embodiment, the auxiliary frame is configured to take a ground potential.

  In the optical semiconductor device of this embodiment, since the auxiliary frame takes a ground potential (ground potential), a higher shielding effect can be obtained. Therefore, an optical semiconductor device with better optical transmission quality can be realized.

In the optical semiconductor device of one embodiment,
The lead frame includes a header portion on which the optical semiconductor element is mounted, and a ground terminal connected to the header portion and extending to the outside of the mold resin portion,
The auxiliary frame includes a facing portion facing the header portion of the lead frame, and a connection terminal connected to the facing portion and extending along the ground terminal of the lead frame and electrically connected thereto. To do.

  In the optical semiconductor device of this embodiment, the auxiliary frame can easily take the ground potential by grounding the ground terminal of the lead frame. In addition, since the connection terminal of the auxiliary frame extends along the ground terminal of the lead frame at the manufacturing stage of the optical semiconductor device, they can be easily and accurately electrically (and mechanically) connected. it can. Therefore, this optical semiconductor device can be made small and inexpensive.

  In the optical semiconductor device of one embodiment, the connection terminal of the auxiliary frame and the ground terminal of the lead frame are connected by welding.

  In the optical semiconductor device of this embodiment, the connection terminal of the auxiliary frame and the ground terminal of the lead frame are connected by welding. Therefore, at the manufacturing stage of the optical semiconductor device, the connection terminal of the auxiliary frame and the ground terminal of the lead frame are securely and easily connected electrically and mechanically by welding. Therefore, the optical semiconductor device can be made small and inexpensive.

In the optical semiconductor device of one embodiment, the difference between the linear expansion coefficient of the lead frame and the auxiliary frame and the linear expansion coefficient of the mold resin portion is in the range of 0 to 6.0 × 10 ⁻⁵ K ^−1. As described above, a transparent filler is mixed in the mold resin portion.

In the optical semiconductor device according to this embodiment, the difference between the linear expansion coefficient of the lead frame and the auxiliary frame and the linear expansion coefficient of the mold resin portion is in the range of ⁰ to 6.0 × 10 ⁻⁵ K ^−1. Therefore, it is possible to reduce problems such as disconnection of the bonding wire and peeling of the chip caused by thermal stress. Therefore, a more reliable optical semiconductor device can be realized.

  In the optical semiconductor device of one embodiment, the ratio of the transparent filler in the mold resin portion is in the range of 20 wt% to 80 wt%.

  In the optical semiconductor device of this embodiment, since the ratio of the transparent filler in the mold resin portion is in the range of 20 wt% to 80 wt%, the lead frame and the lead frame The difference between the linear expansion coefficient of the auxiliary frame and the linear expansion coefficient of the mold resin portion can be reduced, and the thermal conductivity can be increased. Therefore, a highly reliable optical semiconductor device with good optical transmission quality can be realized.

  In the optical semiconductor device of one embodiment, the refractive index of the transparent filler is substantially equal to the refractive index of an epoxy resin that is a base material of the mold resin portion.

  According to the optical semiconductor device of this embodiment, since the refractive index of the transparent filler is substantially equal to the refractive index of the epoxy resin that is the base material of the mold resin part, the optical signal due to scattering in the mold resin part is obtained. Attenuation can be reduced. Therefore, an optical semiconductor device with better optical transmission quality can be realized.

  In the optical semiconductor device of one embodiment, the transparent filler has a spherical shape.

  According to the optical semiconductor device of this embodiment, due to the shape of the transparent filler, stress damage to the optical semiconductor element, the buffer resin portion, the auxiliary frame, and the lead frame due to the transparent filler can be reduced. Therefore, a highly reliable optical semiconductor device can be realized.

  In the optical semiconductor device of one embodiment, the mold resin portion covers an outer surface of the facing portion of the auxiliary frame, and has a lens portion convex outward at a portion corresponding to the opening. And

  Here, the “outer surface” of the facing portion refers to a surface opposite to the surface facing the optical semiconductor element. Further, “outside” refers to the outside of the mold resin portion.

  In the optical semiconductor device of this embodiment, the mold resin portion has a lens portion that is convex outward at a portion corresponding to the opening of the auxiliary frame. Therefore, the efficiency of light reception or light emission can be further improved. Therefore, an optical semiconductor device with better optical transmission quality can be realized.

  An electronic apparatus of the present invention is an electronic apparatus comprising the optical semiconductor device of the present invention.

  Since the electronic apparatus according to the present invention includes the optical semiconductor device, optical transmission with high reliability and good optical transmission quality is possible.

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
(First embodiment)
FIG. 1 shows a schematic cross-sectional structure of an optical semiconductor device according to the first embodiment (the whole is denoted by reference numeral 1).

  The optical semiconductor device 1 is disposed along the lead frame 4, the optical semiconductor element 3 mounted on the lead frame 4, and a predetermined gap with respect to the optical semiconductor element 3 along the lead frame 4. An auxiliary frame 8, a buffer resin portion 7 made of a translucent resin provided so as to cover the optical semiconductor element 3, and a mold resin portion 11 made of a translucent resin are provided. Reference numeral 5 collectively indicates wires bonded to the surface 3 a of the optical semiconductor element 3.

  FIG. 2 shows the optical semiconductor device 1 as viewed from the front (as viewed from the optical fiber 2 side in FIG. 1). For ease of understanding, only the contour of the mold resin portion 11 is drawn in FIG.

  As can be clearly seen from FIG. 2, the lead frame 4 includes a rectangular header portion 41 on which the optical semiconductor element 3 is mounted, and a ground terminal 42 that is connected to the header portion 41 and extends to the outside of the mold resin portion 11. And lead terminals 43, 44, 45 arranged around the header portion 41. Each electrode pad (not shown) provided on the surface of the optical semiconductor element 3 is electrically connected to the corresponding ground terminal 42 and lead terminals 43, 44, 45 by wires 51, 52, 53, 54, respectively. ing.

  4A shows a side cross section of the auxiliary frame 8 (corresponding to the cross section in FIG. 1), and FIG. 4B shows the auxiliary frame 8 viewed from the left side in FIG. 4A. Yes. As can be clearly understood from FIG. 4A and FIG. 1, the auxiliary frame 8 is connected to the facing portion 81 facing the header portion 41 of the lead frame 4 and the facing portion 81, and is connected to the ground terminal 42 of the lead frame 4. A neck portion 84, a bent portion 83, and a connection terminal 82 extending along the long side are included. In this example, the connection terminal 82 of the auxiliary frame 8 and the ground terminal 42 of the lead frame 4 are electrically and mechanically connected to each other by welding. The code | symbol 10 has shown the welding location.

  The bent portion 83 of the auxiliary frame 8 is provided between the facing portion 81 and the optical semiconductor element 3 in order to ensure a gap for arranging the wire 5 for the optical semiconductor element 3. This gap will be described in detail later.

  4B and FIG. 2, in this example, the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8 are set to have the same planar dimensions. The ground terminal 42 of the lead frame 4 and the elongated portions 84, 83, 82 of the auxiliary frame 8 are set to have the same width.

  In addition, a circular through hole 12 as an opening is formed in the center of the facing portion 81 of the auxiliary frame 8. As shown in FIG. 1, the through hole 12 is provided at a position corresponding to the optical portion (a portion that actually receives or emits light) 6 of the optical semiconductor element 3. Therefore, the optical part 6 of the optical semiconductor element 3 can receive light from the outside through the mold resin part 11, the opening 12 of the opposing part 81 of the auxiliary frame 8, and the buffer resin part 7, or can emit light to the outside. That is, the optical part 6 of the optical semiconductor element 3 is not shielded by the facing part 81 of the auxiliary frame 8. Therefore, an optical semiconductor device having high coupling efficiency can be realized.

  In this example, the optical semiconductor device 1 is a receiver, and the optical semiconductor element 3 is obtained by integrating a light receiving element as an optical unit 6 and a signal processing circuit into one chip as an integrated circuit. Since it is made into one chip, wire bonding is not required between the light receiving element and the signal processing circuit, the stray capacitance is reduced, high-speed response is possible, and it is less susceptible to electromagnetic noise. Further, since the number of chips is reduced, manufacturing is facilitated, and cost can be reduced.

  The lead frame 4 and the auxiliary frame 8 are made of, for example, a conductive metal material. The mold resin part 11 is made of, for example, an epoxy resin.

  The buffer resin portion 7 is made of a translucent silicone resin having cold resistance. By using a silicone resin having translucency and cold resistance as the material of the buffer resin portion 7, the stress applied to the bonding wire 5 and the optical semiconductor element 3 at a low temperature can be reduced. Therefore, a highly reliable optical semiconductor device can be realized.

  The translucent silicone resin forming the buffer resin portion 7 is filled in the gap between the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8 while covering the outer surface of the optical semiconductor element 3. Thereby, the stress applied to the bonding wire 5 for electrical connection of the optical semiconductor element 3 and the outer surface of the optical semiconductor element 3 can be reduced. Further, it is possible to prevent peeling and cracking between the auxiliary frame 8 and the buffer resin portion 7. Therefore, an optical semiconductor device with higher reliability can be realized.

  The mold resin portion 11 includes a lens 9 that is convex toward the outside at a portion corresponding to the through hole 12 of the auxiliary frame 8, and thus at a portion corresponding to the optical portion 6 of the optical semiconductor element 3. Therefore, the optical coupling efficiency between the optical part 6 of the optical semiconductor element 3 and the optical fiber 2 can be increased, and the efficiency of light reception (or light emission) can be further improved. Therefore, an optical semiconductor device with better optical transmission quality can be realized.

  The above-described optical semiconductor device 1 is manufactured as follows. Initially, each part of the lead frame 4 is integrally connected by a tie bar (not shown).

  First, as shown in FIG. 3, the optical semiconductor element 3 is mounted by die bonding at a predetermined position of the header portion 41 of the lead frame 4. At this time, a conductive resin (not shown) such as a silver paste is applied between the back surface (electrode) 3 b of the optical semiconductor element 3 and the element mounting surface 41 a of the header portion 41. Thereby, the header part 41 of the lead frame 4 and the back surface electrode 3b of the optical semiconductor element 3 are electrically connected. Thereafter, wire bonding is performed to electrically connect each electrode pad (not shown) provided on the surface 3a of the optical semiconductor element 3 and the ground terminal 42 of the lead frame 4 by the wire 5 made of a gold wire, an aluminum wire, or the like. Connect.

  Next, as shown in FIG. 5, the lead frame 4 on which the optical semiconductor element 3 is mounted and the auxiliary frame 8 are positioned and overlapped with each other.

In this example, the distance between the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8 is d, and the height of the optical semiconductor element 3 from the element mounting surface 41a of the header 41 is H1. When the height from the surface 3a of the wire 5 bonded to the surface 3a of the optical semiconductor element 3 is H2,
d> H1 + H2
The relationship is satisfied. Thereby, a gap for arranging the wire 5 to the optical semiconductor element 3 can be secured between the facing portion 81 and the optical semiconductor element 3. That is, because the above relationship is satisfied, the inner surface 81 b of the facing portion 81 of the auxiliary frame 8 does not come into contact with the wire 5 bonded to the surface 3 a of the optical semiconductor element 3. Therefore, the wire 5 is not deformed or short-circuited due to contact during actual operation after the manufacturing stage or after completion, and an optical semiconductor device with higher reliability can be realized.

  Next, as shown in FIG. 6, a translucent silicone resin that forms the buffer resin portion 7 is injected through the through hole 12 provided in the facing portion 81 of the auxiliary frame 8 so as to cover the optical semiconductor element 3. The gap between the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8 is filled. At this time, the translucent silicone resin overflows from the through-hole 12 to the outer surface 81a of the opposing portion 81 so that the surface 7a of the buffer resin portion 7 (translucent silicone resin) matches the outer surface 81a of the opposing portion 81. Do not. Thereby, the height of the buffer resin part 7 can be made uniform. At this time, the translucent silicone resin contacts both the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8, and surface tension acts on the resin surface exposed in the gap. Therefore, even if there is some variation in the filling amount, the variation in the filling amount is caused by the resin surface exposed in the gap being convexly curved outward and bulging, or conversely curved inwardly and retracted. Is easily absorbed. Therefore, the buffer resin portion 7 can be easily formed with high accuracy.

  Next, transfer molding is performed using an epoxy resin to form the mold resin portion 11 shown in FIG. The mold resin part 11 seals the optical semiconductor element 3 covered with the buffer resin part 7, the header part 41 of the lead frame 4, the opposing part 81 of the auxiliary frame 8, the neck part 84 and the bending part 83. Stop.

  Next, welding is performed to mechanically and electrically connect the ground terminal 42 of the lead frame 4 and the connection terminal 82 of the auxiliary frame 8. Thereby, the auxiliary frame 8 can easily take the ground potential by grounding the ground terminal 42. Thereby, a high shielding effect for the optical semiconductor element 3 is obtained. Therefore, an optical semiconductor device with better optical transmission quality can be realized. In particular, in this example, since the optical semiconductor element 3 includes a signal processing circuit, the shielding effect by the auxiliary frame 8 works effectively. Accordingly, an optical semiconductor device having higher quality transmission characteristics can be realized.

  Thereafter, the above-described tie bar (not shown) connecting the respective parts of the lead frame 4 is cut. The optical semiconductor device 1 is manufactured in this way.

  In this optical semiconductor device 1, the auxiliary frame 8 is disposed in the vicinity of the optical semiconductor element 3 including the signal processing circuit along the lead frame 4. Therefore, the heat generated by the optical semiconductor element 3 including the signal processing circuit can be released not only through the lead frame 4 but also through the buffer resin portion 7 and the auxiliary frame 8 to the outside of the optical semiconductor device 1 and the entire mold resin portion 11. Can diffuse. When heat diffuses to almost the entire mold resin portion 11, heat is likely to diffuse from the mold resin portion 11 to the outside (air). Therefore, it is possible to prevent the temperature from rising due to heat accumulation in the optical semiconductor element 3 which is a heat source during operation. Therefore, an optical semiconductor device having excellent environmental resistance can be realized. In particular, even when the optical semiconductor element 3 having a small chip size is used, the heat generated by the optical semiconductor element 3 is diffused over almost the entire mold resin portion 11, so that the outside of the outer peripheral surface of the mold resin portion 11 can be externally applied. The effect of heat dissipation is increased.

  In addition, the optical semiconductor device 1 has a configuration in which the optical semiconductor element 3 covered with the buffer resin portion 7, the header portion 41 of the lead frame 4, the facing portion 81 of the auxiliary frame 8, and the like are integrally sealed. Therefore, it has a simple configuration. Therefore, both size reduction and price reduction can be achieved. In addition, since a glass lens or the like is not mounted on the optical semiconductor element 3, a small-sized optical semiconductor element can be used.

In the above example, the opening provided in the facing portion 81 of the auxiliary frame 8 is the circular through-hole 12, but is not limited thereto. The shape of the opening may be any shape as long as it does not block the optical path between the optical fiber 2 and the optical semiconductor element 3. The opening may be a slit.
(Second Embodiment)
FIG. 7 shows a schematic cross-sectional structure of the optical semiconductor device of the second embodiment (the whole is denoted by reference numeral 16). For ease of understanding, the same reference numerals are used for the same components as those in the first embodiment (the same applies to later-described embodiments).

  The optical semiconductor device 16 is arranged with a predetermined gap with respect to the optical semiconductor element 13 along the lead frame 4A, the optical semiconductor element 13 mounted on the lead frame 4A, and the lead frame 4A. The auxiliary frame 8A, a buffer resin portion 7 made of a translucent resin provided so as to cover the optical semiconductor element 13, and a mold resin portion 11 made of a translucent resin are provided. Reference numeral 5 </ b> A collectively indicates wires bonded to the surface of the optical semiconductor element 13.

  FIG. 8 shows the optical semiconductor device 16 as viewed from the front (as viewed from the optical fiber 2 side in FIG. 7). For ease of understanding, only the contour of the mold resin portion 11 is drawn in FIG.

  As can be clearly seen from FIG. 8, the lead frame 4 </ b> A is connected to the rectangular first header portion 41 </ b> A on which the LED 13 as the optical semiconductor element is mounted and the first header portion 41 </ b> A and extends to the outer peripheral surface of the mold resin portion 11. A supporting portion 42A that is present, a rectangular second header portion 47A on which the LED drive circuit 14 as a signal processing circuit is mounted, and a ground terminal 48A that continues to the second header portion 47A and extends to the outside of the mold resin portion 11. And lead terminals 43A, 44A, 45A arranged in the vicinity of the header portions 41A, 47A. An electrode pad (not shown) provided on the surface of the LED 13 and the corresponding lead terminal 46 </ b> A are electrically connected by a wire 60. In addition, electrode pads (not shown) provided on the surface of the LED drive circuit 14 and the corresponding lead terminals 43A, 44A, 45A and header portions 47A, 41A are respectively provided with wires 55, 56, 57, 58, 59. Are electrically connected.

  FIG. 9A shows a side cross section of the auxiliary frame 8A (corresponding to the cross section in FIG. 7), and FIG. 9B shows the auxiliary frame 8A viewed from the left side in FIG. 9A. Yes. As can be clearly understood from FIGS. 9A and 7, the auxiliary frame 8A is connected to the rectangular facing portion 81A facing both the header portions 41A and 47A of the lead frame 4A and the facing portion 81A. It includes a bent portion 83A and a connecting terminal 82A extending along the 4A ground terminal 48A. In this example, the connection terminal 82A of the auxiliary frame 8A and the ground terminal 42A of the lead frame 4A are electrically and mechanically connected to each other by welding. The code | symbol 10 has shown the welding location.

  As can be clearly seen from FIGS. 9B and 8, in this example, the facing portion 81A of the auxiliary frame 8A is set to have a larger planar dimension than the header portions 41A and 47A of the lead frame 4A. The ground terminal 42A of the lead frame 4A and the elongated portions 83A and 82A of the auxiliary frame 8A are set to have the same width.

  Further, a circular through hole 12 as an opening and another through hole 15 are formed in the facing portion 81A of the auxiliary frame 8A. As shown in FIG. 7, the through-hole 12 is provided at a position corresponding to the optical part (part that actually emits) 6 </ b> A of the LED 13. Therefore, the optical part 6 </ b> A of the LED 13 can receive or emit light through the through hole 12. That is, the optical part 6A of the LED 13 is not shielded by the facing part 81A. Therefore, an optical semiconductor device having high coupling efficiency can be realized. The other through-hole 15 is used only for injecting a translucent resin that forms a buffer resin portion in the manufacturing stage of the optical semiconductor device 16.

  The translucent silicone resin that forms the buffer resin portion 7 is filled in the gap between the header portion 41A of the lead frame 4A and the opposing portion 81A of the auxiliary frame 8A while covering the optical semiconductor element 3. Thereby, the stress added to the bonding wire 60 for electrical connection of LED13 and the outer surface of LED13 can be reduced. Although not shown, while covering the LED drive circuit 14, a buffer resin portion (hereinafter, the same reference numeral 7) is provided in the gap between the header portion 47A of the lead frame 4A and the opposing portion 81A of the auxiliary frame 8A. The light-transmitting silicone resin is filled. The stress applied to the bonding wires 55, 56, 57, 58, 59 for electrical connection of the LED drive circuit 14 and the outer surface of the LED drive circuit 14 can be reduced. As a result, it is possible to prevent peeling and cracking between the auxiliary frame 8A and the buffer resin portion 7 covering the LED 13 and the buffer resin portion 7 covering the LED drive circuit 14. Therefore, an optical semiconductor device with higher reliability can be realized.

  The above-described optical semiconductor device 16 is manufactured in substantially the same manner as the optical semiconductor device 1 of the first embodiment.

  That is, in the die bonding process, the LED 13 is mounted on the header portion 41A of the lead frame 4A shown in FIG. 8, and the LED drive circuit 14 is mounted on the header portion 47A. In this optical semiconductor device 16, since a glass lens or the like is not mounted on the optical semiconductor element, an optical semiconductor element having a small size such as the LED 13 can be used.

  In the wire bonding step, wires 55, 56, 57, 58 and 59 for the LED drive circuit 14 are wired together with the wire 60 for the LED 13.

  After the lead frame 4 </ b> A and the auxiliary frame 8 </ b> A are positioned and overlapped with each other, a translucent silicone resin constituting each buffer resin portion 7 is injected through the through holes 12 and 15. At this time, the surface 7a of each buffer resin portion 7 (translucent silicone resin) is made to coincide with the outer surface 81a of the facing portion 81A, so that the translucent silicone resin passes through the through holes 12 and 15 and the outer surface 81a of the facing portion 81A. Do not overflow. Thereby, the height of each buffer resin part 7 can be made uniform. At this time, the translucent silicone resin contacts both the header portions 41A and 47A of the lead frame 4A and the facing portion 81A of the auxiliary frame 8A, and the surface tension is applied to the resin surface exposed in the gap between them. work. Therefore, even if there is a slight variation in the filling amount, the variation in the filling amount is easily absorbed. Therefore, each buffer resin portion 7 can be easily formed with high accuracy.

  Similarly to the first embodiment, the translucent silicone resin forming each buffer resin portion 7 is assumed to have cold resistance. Further, instead of the cold-resistant silicone resin, an epoxy resin having a small difference in coefficient of linear expansion among the lead frame 4A, the auxiliary frame 8A, and the bonding wire 5A may be used. Furthermore, by using a resin in which an epoxy resin is filled with a transparent filler, the difference in linear expansion coefficient is further reduced, and a highly reliable optical transmission device can be realized.

  In this example, the translucent silicone resin that forms each buffer resin portion 7 is injected through the through holes 12 and 15, but the header portion 41A of the lead frame 4A from around the header portions 41A and 47A of the lead frame 4A. , 47A and the gap between the opposing portion 81A of the auxiliary frame 8A. Even in such a case, surface tension acts on the resin surface exposed in the gap. Therefore, even if there is a slight variation in the filling amount, the variation in the filling amount is easily absorbed. Therefore, each buffer resin portion 7 can be easily formed with high accuracy.

  The transfer molding process is performed in the same manner as in the first embodiment, and the mold resin portion 11 is formed. Further, the welding process is performed in the same manner as in the first embodiment, and the welded portion 10 is formed. Thereafter, the above-described tie bar (not shown) connecting the respective parts of the lead frame 4A is cut. The optical semiconductor device 16 is manufactured in this way.

  Similar to the optical semiconductor device 1 of the first embodiment, the optical semiconductor device 16 has high coupling efficiency and optical transmission quality. In addition, it has excellent environmental resistance and high reliability. In addition, both a reduction in size and a reduction in price can be achieved with a simple configuration.

(Third embodiment)
FIG. 10 shows a schematic cross-sectional structure of the optical semiconductor device according to the third embodiment (the whole is denoted by reference numeral 17).

  This optical semiconductor device 17 is different from the optical semiconductor device 1 of the first embodiment only in that another auxiliary frame 8B is provided instead of the above-described auxiliary frame 8 (see FIG. 1).

  FIG. 11A shows a side cross section of the auxiliary frame 8B (corresponding to the cross section in FIG. 10), and FIG. 11B shows the auxiliary frame 8B viewed from the right side in FIG. Yes. As can be seen from these drawings, the auxiliary frame 8B includes an insulating layer 19 on the surface (inner surface) 81b of the facing portion 81 facing the optical semiconductor element 3. The insulating layer 19 is made of an insulating paint, a resin, or a metal plating having no conductivity.

  At the manufacturing stage of the optical semiconductor device 17, the distance between the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8B is narrower than the design value due to the influence of some external force, and the facing portion 81 of the auxiliary frame 8B. Even if the wire 5 comes into contact with the wire 5, the inner surface 81 b of the facing portion 81 includes the insulating layer 19, so that problems such as a short circuit do not occur. Therefore, an optical semiconductor device with higher reliability can be realized.

  Since there is no possibility of a short circuit or the like in this way, it is possible to reduce the design value of the distance between the header portion 41 of the lead frame 4 and the facing portion 81 of the auxiliary frame 8B. In such a case, it is possible to realize an optical semiconductor device with further shielding effect and higher heat dissipation. Further, the size can be further reduced by reducing the design value of the interval.

  The auxiliary frame 8B having the insulating surface 81b as described above is not limited to the case where the optical semiconductor element and the signal processing circuit are integrated into one chip, but the optical semiconductor element and the signal processing circuit have different chip configurations. It can also be applied in some cases.

(Fourth embodiment)
FIG. 12 shows a schematic cross-sectional structure of an optical semiconductor device (the whole is denoted by reference numeral 20) of the fourth embodiment.

  This optical semiconductor device 20 is different from the optical semiconductor device 1 of the first embodiment only in that a mold resin portion 21 made of another material is provided instead of the above-described mold resin portion 11 (see FIG. 1). Is different.

  The mold resin portion 21 is made of an epoxy resin mixed with a transparent filler.

In this way, by using an epoxy resin mixed with a transparent filler as the material of the mold resin portion 21, the difference between the linear expansion coefficient of the auxiliary frame 8 and the lead frame 4 and the linear expansion coefficient of the mold resin portion 21 is reduced. It is possible. That is, by adjusting the ratio of the transparent filler in the mold resin portion 21, the difference in linear expansion coefficient can be set to 0 to 6.0 × 10 ⁻⁵ K ⁻¹ .

In this way, by setting the difference between the linear expansion coefficient of the auxiliary frame 8 and the lead frame 4 and the linear expansion coefficient of the mold resin portion 21 to 0 to 6.0 × 10 ⁻⁵ K ⁻¹ , the auxiliary frame 8 and the lead frame It is possible to reduce defects such as disconnection of the bonding wire, chip peeling, interfacial peeling of the resin, and cracks due to a thermal contraction difference (thermal stress) between 4 and the mold resin portion 21. Thereby, defects, such as moisture resistance, can be reduced. Therefore, a more reliable optical semiconductor device can be realized.

  The refractive index of the transparent filler is desirably substantially equal to or close to the refractive index of the epoxy resin that is the base material of the mold resin portion 21. In such a case, attenuation of the optical signal due to scattering in the mold resin portion 21 can be reduced. Therefore, high coupling efficiency can be obtained, and an optical semiconductor device with better optical transmission quality can be realized. In particular, when a light emitting element is mounted as the optical semiconductor element 3, an increase in driving current of the light emitting element can be prevented, and as a result, an increase in power consumption can be suppressed. Therefore, an optical semiconductor device with high reliability at high temperatures can be realized.

  As described above, the mold resin portion 21 made of an epoxy resin mixed with a transparent filler is not limited to the case where the optical semiconductor element and the signal processing circuit are integrated into one chip, but the optical semiconductor element and the signal processing circuit are separately provided. The present invention can also be applied to a chip configuration.

  Further, the mold resin portion 21 made of epoxy resin mixed with a transparent filler is used as a constituent element of the optical semiconductor device together with the auxiliary frame 8B having the inner surface 81b having insulation as described in the third embodiment. Can be applied.

(Fifth embodiment)
In the fifth embodiment, in the optical semiconductor device 20 of the fourth embodiment, the ratio of the transparent filler in the mold resin portion 21 is optimized within a range of 20 wt% to 80 wt%, as shown in FIG. It explains using.

  If the ratio of the transparent filler in the mold resin portion 21 is optimized within a range of 20 wt% to 80 wt%, the linear expansion coefficients of the lead frame 4 and the auxiliary frame 8 and the mold resin can be maintained while maintaining high transmittance. The difference from the linear expansion coefficient of the portion 21 can be reduced, and the thermal conductivity can be increased. Therefore, a highly reliable optical semiconductor device with good optical transmission quality can be realized.

  Such optimization of the ratio of the transparent filler is not limited to the case where the optical semiconductor element and the signal processing circuit are integrated into one chip, but also when the optical semiconductor element and the signal processing circuit have different chip configurations. obtain.

  Moreover, the mold resin part 21 in which the ratio of the transparent filler is optimized is applied as a constituent element of the optical semiconductor device together with the auxiliary frame 8B having the insulating surface 81b as described in the third embodiment. Can be done.

(Sixth embodiment)
In the sixth embodiment, the fact that the shape of the transparent filler in the mold resin portion 21 in the optical semiconductor device 20 of the fourth embodiment is spherical will be described with reference to FIG.

  If the shape of the transparent filler is spherical, stress damage to the optical semiconductor element 3, the buffer resin portion 7, the auxiliary frame 8 and the lead frame 4 due to the transparent filler can be reduced. Thereby, resin interface peeling or the like is less likely to occur. Therefore, a highly reliable optical semiconductor device can be realized.

  The spherical shape of the transparent filler is not limited to the case where the optical semiconductor element and the signal processing circuit are integrated into one chip, but also when the optical semiconductor element and the signal processing circuit have different chip configurations. Can be applied.

  Further, the mold resin portion 21 mixed with the spherical transparent filler is applied as a constituent element of the optical semiconductor device together with the auxiliary frame 8B whose inner surface 81b has an insulating property as described in the third embodiment. obtain.

(Seventh embodiment)
FIG. 13 shows a schematic cross-sectional structure of an optical semiconductor device (generally indicated by reference numeral 22) of the seventh embodiment. For ease of understanding, the same reference numerals are used for the same components as those in the first embodiment.

  The optical semiconductor device 22 is different from the optical semiconductor device 1 according to the first embodiment in the light transmitting property inside a mold resin portion 24 made of a light transmitting resin (the same material as the mold resin portion 11 in FIG. 1). The only difference is that a core portion 23 made of a non-translucent resin different from the conductive resin is provided. In addition, the mold resin part 24 has the lens part 9 similarly to the mold resin part 11 in FIG.

  Specifically, the core portion 23 of the optical semiconductor device 22 includes the optical semiconductor element 3 covered with the buffer resin portion 7, the header portion 41 of the lead frame 4, the opposing portion 81 of the auxiliary frame 8, and the neck portion 84. In addition, the bent portion 83 and the bent portion 83 are integrally sealed, and an opening 25 is provided at a portion corresponding to the opening 12 of the facing portion 81. The shape of the opening 25 is circular, and is set to a size slightly larger than the opening 12 of the facing portion 81 in consideration of misalignment in the transfer molding process. In addition, in this example, the end face 26 of the opening 25 is formed in a tapered shape that opens outward so as not to block the optical path between the optical fiber 2 and the optical semiconductor element 3.

  This structure is easily manufactured by performing a transfer mold for forming the core portion 23 and a transfer mold for forming the mold resin portion 24 surrounding the core portion 23.

  According to this structure, the optical part 6 of the optical semiconductor element 3 receives light from outside through the mold resin part 11, the opening 25 of the core part 23, the opening 12 of the facing part 81 of the auxiliary frame 8, and the buffer resin part 7. Alternatively, light can be emitted to the outside. That is, the optical part 6 of the optical semiconductor element 3 is not shielded by the resin forming the core part 23 or the facing part 81 of the auxiliary frame 8. Therefore, an optical semiconductor device having high coupling efficiency can be realized.

  In addition, in this optical semiconductor device, since the core part 23 may have a low light transmittance, the amount of filler added to the base material of the core part 23 can be increased. This facilitates reducing the difference between the thermal expansion coefficient of the core portion 23 and the thermal expansion coefficients of the lead frame 4, the auxiliary frame 8 and the bonding wire 5. In such a case, the bonding wire 5 is not easily broken by thermal stress. Therefore, an optical semiconductor device with high reliability and good optical transmission quality can be realized. Moreover, since it is possible to increase the addition amount of a filler, it becomes possible to enlarge the thermal conductivity of the core part 23. FIG. Therefore, the effect of heat dissipation can be increased, and an optical semiconductor device with high reliability at high temperatures can be realized.

  On the other hand, the difference between the linear expansion coefficient of the resin forming the core portion 23 and the linear expansion coefficient of the translucent resin forming the mold resin portion 24 can be reduced. In such a case, interface peeling between the core part 23 and the mold resin part 24 can be reduced, and a package crack due to thermal stress is unlikely to occur. Therefore, a highly reliable optical semiconductor device can be realized.

  Further, the difference between the linear expansion coefficient of the resin forming the mold resin portion 24 and the linear expansion coefficient of the resin forming the buffer resin portion 7 can be reduced. In such a case, interfacial peeling between the mold resin portion 24 and the auxiliary frame 8 and the buffer resin portion 7 can also be reduced. Therefore, an optical semiconductor device with higher reliability can be realized.

  The structure (double transfer mold structure) in which the core portion 23 made of a non-translucent resin different from the translucent resin is provided inside the mold resin portion 24 made of the translucent resin as described above. The present invention is not limited to the case where the semiconductor element and the signal processing circuit are integrated into one chip, but can also be applied to a case where the optical semiconductor element and the signal processing circuit have different chip configurations.

  Further, the double transfer mold structure can be applied as a constituent element of the optical semiconductor device together with the auxiliary frame 8B whose inner surface 81b has an insulating property as described in the third embodiment.

  In an electronic device including the above-described optical semiconductor device, optical transmission with high reliability and good optical transmission quality is possible.

1 is a diagram showing a schematic cross-sectional structure of an optical semiconductor device according to a first embodiment of the present invention. It is a figure which shows the place which looked at the optical semiconductor device of FIG. 1 from the front (left side in FIG. 1). It is a figure which shows the place which mounted the optical semiconductor element 3 in the lead frame 4 of the said optical semiconductor device. 4A is a view showing a side cross section (corresponding to the cross section in FIG. 1) of the auxiliary frame of the optical semiconductor device, and FIG. 4B is a view of the auxiliary frame from the left side in FIG. 4A. FIG. It is a figure which shows the place where the lead frame and the auxiliary | assistant frame which mount an optical semiconductor element were mutually positioned and overlapped. Shows the formation of the buffer resin part by injecting translucent silicone resin. It is a figure which shows schematic sectional structure of the optical semiconductor device of 2nd Embodiment of this invention. It is a figure which shows the place which looked at the optical semiconductor device of FIG. 7 from the front (left side in FIG. 7). FIG. 9A is a view showing a side cross section (corresponding to the cross section in FIG. 7) of the auxiliary frame of the optical semiconductor device, and FIG. 9B is a view of the auxiliary frame from the left side in FIG. FIG. It is a figure which shows schematic sectional structure of the optical semiconductor device of 3rd Embodiment of this invention. FIG. 11A is a view showing a side cross section (corresponding to the cross section in FIG. 10) of the auxiliary frame of the optical semiconductor device, and FIG. 11B is a view of the auxiliary frame from the right side in FIG. FIG. It is a figure which shows schematic sectional structure of the optical semiconductor device of 4th, 5th, 6th embodiment of this invention. It is a figure which shows schematic sectional structure of the optical semiconductor device of 7th Embodiment of this invention. It is a figure which shows the cross-section of the conventional optical semiconductor device. It is a figure which shows the cross-section of the other conventional optical semiconductor device. It is a figure which shows the cross-section of the other conventional optical semiconductor device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 16, 17, 20, 22 Optical semiconductor device 2 Optical fiber 3 Optical semiconductor element 4, 4A Lead frame 5, 5A Bonding wire 6 Optical part 7 Buffer resin part 8, 8A, 8B Auxiliary frame 9 Lens part 10 Welded part 11 , 21, 24 Mold resin part 12, 15 Through hole 13 LED
14 Signal processing circuit 19 Insulating layer 23 Core part 41 Header part 81, 81A Opposite part

Claims (20)

A lead frame,
An optical semiconductor element mounted on the lead frame;
An auxiliary frame disposed along the lead frame with a predetermined gap with respect to the optical semiconductor element;
A buffer resin portion made of a translucent resin provided between the lead frame and the auxiliary frame and covering an outer surface of the optical semiconductor element;
An optical semiconductor element covered with the buffer resin part; and a mold resin part made of a translucent resin that seals at least a part of the lead frame and the auxiliary frame along the optical semiconductor element. An optical semiconductor device characterized by that. The optical semiconductor device according to claim 1,
The optical semiconductor element has an optical part that receives or emits light on the surface opposite to the surface attached to the lead frame among the outer surfaces of the optical semiconductor element,
The auxiliary frame has a facing portion facing the header portion on which the optical semiconductor element of the lead frame is mounted, and an opening is provided in a portion corresponding to the optical portion of the facing portion. An optical semiconductor device. The optical semiconductor device according to claim 2,
Inside the mold resin part, a core part made of a resin different from the translucent resin forming the mold resin part is provided,
The core portion integrally seals the optical semiconductor element covered with the buffer resin portion, the header portion of the lead frame, and the facing portion of the auxiliary frame, and corresponds to the opening of the facing portion. An optical semiconductor device having an opening at a site. The optical semiconductor device according to claim 1,
A signal processing circuit mounted on the lead frame and processing the output of the optical semiconductor element;
The optical semiconductor device, wherein the signal processing circuit is located between the lead frame and the auxiliary frame. The optical semiconductor device according to claim 4,
An optical semiconductor device, wherein the optical semiconductor element and the signal processing circuit are included in one chip. The optical semiconductor device according to claim 1,
The said buffer resin part consists of a silicone resin which has translucency and cold resistance, The optical semiconductor device characterized by the above-mentioned. The optical semiconductor device according to claim 1,
The said buffer resin part consists of an epoxy resin with which the transparent filler was mixed, The optical semiconductor device characterized by the above-mentioned. The optical semiconductor device according to claim 2,
The distance between the header portion of the lead frame and the facing portion of the auxiliary frame is d, the height of the optical semiconductor element from the lead frame is H1, and the optical semiconductor element is bonded to the surface of the optical semiconductor element. When the height of the wire from the surface is H2,
d> H1 + H2
An optical semiconductor device characterized in that: The optical semiconductor device according to claim 2,
The translucent resin forming the buffer resin portion is filled in a gap between the header portion of the lead frame and the opposing portion of the auxiliary frame while covering the optical semiconductor element. apparatus. The optical semiconductor device according to claim 1,
An optical semiconductor device, wherein the auxiliary frame has conductivity. The optical semiconductor device according to claim 10,
A surface of the auxiliary frame facing the optical semiconductor element has an insulating property. The optical semiconductor device according to claim 10,
An optical semiconductor device characterized in that the auxiliary frame takes a ground potential. The optical semiconductor device according to claim 12,
The lead frame includes a header portion on which the optical semiconductor element is mounted, and a ground terminal connected to the header portion and extending to the outside of the mold resin portion,
The auxiliary frame includes a facing portion facing the header portion of the lead frame, and a connection terminal connected to the facing portion and extending along the ground terminal of the lead frame and electrically connected thereto. An optical semiconductor device. The optical semiconductor device according to claim 13,
The optical semiconductor device, wherein the connection terminal of the auxiliary frame and the ground terminal of the lead frame are connected by welding. The optical semiconductor device according to claim 1,
Transparent to the mold resin portion so that the difference between the linear expansion coefficient of the lead frame and the auxiliary frame and the linear expansion coefficient of the mold resin portion is in the range of 0 to 6.0 × 10 ⁻⁵ K ^−1. An optical semiconductor device in which a filler is mixed. The optical semiconductor device according to claim 15,
An optical semiconductor device characterized in that the ratio of the transparent filler in the mold resin portion is in the range of 20 wt% to 80 wt%. The optical semiconductor device according to claim 15,
An optical semiconductor device, wherein a refractive index of the transparent filler is substantially equal to a refractive index of an epoxy resin which is a base material of the mold resin portion. The optical semiconductor device according to claim 15,
An optical semiconductor device, wherein the transparent filler has a spherical shape. The optical semiconductor device according to claim 2,
The mold resin portion covers an outer surface of the facing portion of the auxiliary frame, and has a lens portion convex outward at a portion corresponding to the opening.   An electronic apparatus comprising the optical semiconductor device according to claim 1.

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