JP2008226968A - Optical communication module - Google Patents

Optical communication module Download PDF

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Publication number
JP2008226968A
JP2008226968A JP2007059830A JP2007059830A JP2008226968A JP 2008226968 A JP2008226968 A JP 2008226968A JP 2007059830 A JP2007059830 A JP 2007059830A JP 2007059830 A JP2007059830 A JP 2007059830A JP 2008226968 A JP2008226968 A JP 2008226968A
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Prior art keywords
light receiving
communication module
light
receiving element
optical communication
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Tomoharu Horio
友春 堀尾
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Rohm Co Ltd
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Rohm Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805—Shape
    • H01L2224/4809—Loop shape
    • H01L2224/48091—Arched
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481—Disposition
    • H01L2224/48151—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48225—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H01L2224/48227—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation connecting the wire to a bond pad of the item
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/1015—Shape
    • H01L2924/10155—Shape being other than a cuboid
    • H01L2924/10158—Shape being other than a cuboid at the passive surface
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15—Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/181—Encapsulation
    • H01L2924/1815—Shape
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/30—Technical effects
    • H01L2924/301—Electrical effects
    • H01L2924/3025—Electromagnetic shielding

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  • Led Device Packages (AREA)
  • Light Receiving Elements (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical communication module capable of preventing a light-receiving element from being separated. <P>SOLUTION: The optical communication module A has: a substrate 1; a light-emitting element 2 mounted on the substrate 1; a light-receiving element 3 that has a light-receiving surface 3a and is mounted on the substrate 1; and a resin package 5 for covering the light-emitting element 2 and the light-receiving element 3. In the optical communication module A, a through hole 1a is formed on the substrate 1. The light-receiving element 3 covers the through hole 1a at least partially; a plurality of recesses 3b are formed at a side part opposite to the light-receiving surface 3a in the light-receiving element 3; and one portion of a resin package 5 covers the plurality of recesses 3b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、電子機器における双方向通信などに用いられる光通信モジュールに関する。   The present invention relates to an optical communication module used for bidirectional communication in an electronic device.

ノートパソコン、携帯電話、電子手帳などの電子機器における双方向通信には、発光素子および受光素子を備えた光通信モジュールが用いられている。このような光通信モジュールには、たとえばＩｒＤＡ準拠の赤外線データ通信モジュールが含まれる。   An optical communication module including a light emitting element and a light receiving element is used for bidirectional communication in electronic devices such as notebook computers, mobile phones, and electronic notebooks. Such optical communication modules include, for example, IrDA compliant infrared data communication modules.

この種の従来の光通信モジュールの一例を図３に示す（たとえば、特許文献１参照）。同図に示された光通信モジュールＸは、ガラスエポキシ樹脂からなる基板９１に搭載された発光素子９２、受光素子９３、駆動ＩＣ９４、および樹脂パッケージ９５を備えている。発光素子９２は、赤外線を発光可能に構成されている。受光素子９３は、受光面に受けた赤外線の光量に応じた起電力を生じることが可能に構成されている。樹脂パッケージ９５は、透明なエポキシ樹脂によって形成されている。樹脂パッケージ９５には、発光素子９２および受光素子９３の正面に位置する２つのレンズ９５ａ，９５ｂが形成されている。発光素子９２から発せられた赤外線は、レンズ９５ａにより指向性を高められて出射される。一方、図中上方から向かってきた赤外線は、レンズ９５ｂにより受光素子９３へと集光される。このようにして、光通信モジュールＸによる赤外線を用いた双方向通信がなされる。   An example of this type of conventional optical communication module is shown in FIG. 3 (see, for example, Patent Document 1). The optical communication module X shown in the figure includes a light emitting element 92, a light receiving element 93, a driving IC 94, and a resin package 95 mounted on a substrate 91 made of glass epoxy resin. The light emitting element 92 is configured to emit infrared light. The light receiving element 93 is configured to generate an electromotive force according to the amount of infrared light received on the light receiving surface. The resin package 95 is formed of a transparent epoxy resin. In the resin package 95, two lenses 95a and 95b positioned in front of the light emitting element 92 and the light receiving element 93 are formed. The infrared rays emitted from the light emitting element 92 are emitted with the directivity enhanced by the lens 95a. On the other hand, the infrared rays traveling from above in the figure are condensed onto the light receiving element 93 by the lens 95b. In this way, bidirectional communication using infrared rays by the optical communication module X is performed.

しかしながら、たとえば光通信モジュールＸを回路基板に実装するときには、光通信モジュールＸ内に熱応力が発生する。この熱応力が過大であると、受光素子９３が基板１から剥離してしまうという問題がある。これにより、受光素子９３とたとえば基板９１に形成された配線パターン（図示略）との導通が阻害されてしまう。あるいは、受光素子９３自体が破損してしまうおそれがある。このようなことでは、光通信モジュールＸによる確実な通信を達成し得ない。   However, for example, when the optical communication module X is mounted on a circuit board, thermal stress is generated in the optical communication module X. If this thermal stress is excessive, there is a problem that the light receiving element 93 is peeled off from the substrate 1. As a result, conduction between the light receiving element 93 and, for example, a wiring pattern (not shown) formed on the substrate 91 is hindered. Alternatively, the light receiving element 93 itself may be damaged. In such a case, reliable communication by the optical communication module X cannot be achieved.

特開２００２−３２４９１６号公報JP 2002-324916 A

本発明は、上記した事情のもとで考え出されたものであって、受光素子の剥離を防止することが可能な光通信モジュールを提供することをその課題とする。   The present invention has been conceived under the circumstances described above, and an object thereof is to provide an optical communication module capable of preventing the light receiving element from being peeled off.

本発明によって提供される光通信モジュールは、基板と、上記基板に搭載された発光素子と、受光面を有しており、かつ上記基板に搭載された受光素子と、上記発光素子および受光素子を覆う樹脂パッケージと、を備える光通信モジュールであって、上記基板には、貫通孔が形成されており、上記受光素子は、上記貫通孔の少なくとも一部を覆っており、上記受光素子のうち上記受光面と反対側の部分には、複数の凹部が形成されており、上記樹脂パッケージの一部は、上記複数の凹部を覆っていることを特徴としている。   An optical communication module provided by the present invention includes a substrate, a light emitting element mounted on the substrate, a light receiving surface, and a light receiving element mounted on the substrate, and the light emitting element and the light receiving element. And a resin package that covers the substrate, wherein the substrate has a through hole formed therein, and the light receiving element covers at least a part of the through hole. A plurality of recesses are formed in a portion opposite to the light receiving surface, and a part of the resin package covers the plurality of recesses.

このような構成によれば、上記受光素子と上記樹脂パッケージとは、上記複数の凹部と上記樹脂パッケージのうちこれらの凹部に入り込む部分とが互いに噛み合うように接合されている。これにより、上記受光素子と上記樹脂パッケージとの接合力を高めることが可能である。したがって、たとえば上記光通信モジュールが実装されるときに熱応力が生じても、上記受光素子が上記樹脂パッケージおよび上記基板から剥離することを抑制可能であり、上記光通信モジュールの通信を確実に行うことができる。   According to such a configuration, the light receiving element and the resin package are joined such that the plurality of recesses and portions of the resin package that enter these recesses mesh with each other. Thereby, it is possible to increase the bonding force between the light receiving element and the resin package. Therefore, for example, even if thermal stress occurs when the optical communication module is mounted, it is possible to suppress the light receiving element from being peeled off from the resin package and the substrate, and the communication of the optical communication module is reliably performed. be able to.

本発明のその他の特徴および利点は、添付図面を参照して以下に行う詳細な説明によって、より明らかとなろう。   Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

以下、本発明の好ましい実施の形態につき、図面を参照して具体的に説明する。   Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

図１は、本発明に係る光通信モジュールの一例を示している。本実施形態の光通信モジュールＡは、基板１、発光素子２、受光素子３、駆動ＩＣ４、および樹脂パッケージ５を備えている。光通信モジュールＡは、たとえばＩｒＤＡ（Infrared Data Association）規格に準拠した赤外線を用いた双方向通信が可能に構成されている。   FIG. 1 shows an example of an optical communication module according to the present invention. The optical communication module A of this embodiment includes a substrate 1, a light emitting element 2, a light receiving element 3, a driving IC 4, and a resin package 5. The optical communication module A is configured to be capable of two-way communication using infrared rays in accordance with, for example, IrDA (Infrared Data Association) standards.

基板１は、たとえばガラスエポキシ樹脂により、全体として平面視長矩形状に形成されている。基板１の表面には、発光素子２、受光素子３、および駆動ＩＣ４に導通する配線パターン（図示略）が形成されている。基板１には、その表面から裏面にかけて貫く貫通孔１ａが形成されている。本実施形態においては、基板１は、その厚さがたとえば０．０６〜０．１０ｍｍ程度とされている。   The board | substrate 1 is formed in planar view long rectangular shape as a whole with glass epoxy resin, for example. On the surface of the substrate 1, a wiring pattern (not shown) that is electrically connected to the light emitting element 2, the light receiving element 3, and the driving IC 4 is formed. The substrate 1 is formed with a through hole 1a penetrating from the front surface to the back surface. In the present embodiment, the substrate 1 has a thickness of about 0.06 to 0.10 mm, for example.

発光素子２は、たとえば、赤外線を発することができる赤外線発光ダイオードなどからなる。発光素子２は、上記基板の上記配線パターンの一部に搭載されている。   The light emitting element 2 is made of, for example, an infrared light emitting diode capable of emitting infrared light. The light emitting element 2 is mounted on a part of the wiring pattern of the substrate.

受光素子３は、たとえば、Ｓｉを用いて形成されたＰＩＮフォトダイオードなどからなり、受光面３ａに赤外線を受光すると、その光量に応じた起電力を生じることが可能に構成されている。受光素子３は、貫通孔１ａを塞ぐように配置されている。図２に示すように、受光素子３のうち受光面３ａと反対側の部分には、複数の凹部３ｂが形成されている。複数の凹部３ｂは、たとえば断面円形状とされており、レーザ加工によって形成されている。   The light receiving element 3 is composed of, for example, a PIN photodiode formed using Si, and is configured to be able to generate an electromotive force corresponding to the amount of light when receiving infrared rays on the light receiving surface 3a. The light receiving element 3 is disposed so as to close the through hole 1a. As shown in FIG. 2, a plurality of recesses 3 b are formed in the portion of the light receiving element 3 opposite to the light receiving surface 3 a. The plurality of recesses 3b have a circular cross section, for example, and are formed by laser processing.

駆動ＩＣ４は、発光素子２および受光素子３による送受信動作を制御するためのものである。駆動ＩＣ４は、ワイヤにより上記配線パターンと接続され、かつ上記配線パターンを通じて発光素子２および受光素子３に接続されている。   The drive IC 4 is for controlling transmission / reception operations by the light emitting element 2 and the light receiving element 3. The driving IC 4 is connected to the wiring pattern by a wire, and is connected to the light emitting element 2 and the light receiving element 3 through the wiring pattern.

樹脂パッケージ５は、たとえばエポキシ樹脂により形成されており、染料を含んだエポキシ樹脂によって形成することにより、赤外線を透過させる一方、ほとんどの可視光を遮蔽する。この樹脂パッケージ５は、トランスファモールド法などの手法により形成されており、発光素子２、受光素子３、および駆動ＩＣ４を覆うように設けられている。樹脂パッケージ５には、２つのレンズ５ａ，５ｂが一体的に形成されている。レンズ５ａは、発光素子２の正面に位置しており、発光素子２から放射された赤外線を指向性を高めて出射するように構成されている。レンズ５ｂは、受光素子３の受光面３ａに対して正対しており、光通信モジュールＡに向けて送信されてきた赤外線を集光して受光素子３の受光面３ａに入射するように構成されている。   The resin package 5 is formed of, for example, an epoxy resin. By forming the resin package 5 using an epoxy resin containing a dye, the resin package 5 transmits infrared rays while shielding most visible light. The resin package 5 is formed by a transfer molding method or the like, and is provided so as to cover the light emitting element 2, the light receiving element 3, and the driving IC 4. Two lenses 5 a and 5 b are integrally formed in the resin package 5. The lens 5a is located in front of the light emitting element 2, and is configured to emit infrared rays emitted from the light emitting element 2 with enhanced directivity. The lens 5 b faces the light receiving surface 3 a of the light receiving element 3, and is configured to collect the infrared light transmitted toward the optical communication module A and to enter the light receiving surface 3 a of the light receiving element 3. ing.

樹脂パッケージ５の一部は、貫通孔１ａ内を満たしている。この樹脂パッケージ５のうち貫通孔１ａ内を満たす部分は、受光素子３の複数の凹部３ｂを覆っている。具体的には、各凹部３ｂ内に樹脂パッケージ５の一部ずつが入り込んでいる構造となっている。本実施形態においては、樹脂パッケージ５のうちレンズ５ａ，５ｂが形成されている部分以外の部分の厚さがたとえば０．３ｍｍ程度とされている。樹脂パッケージ５は、ほとんどの波長の光に対して透光性を有する構成としてもよい。   A part of the resin package 5 fills the inside of the through hole 1a. A portion of the resin package 5 that fills the through hole 1 a covers the plurality of recesses 3 b of the light receiving element 3. Specifically, a part of the resin package 5 is inserted into each recess 3b. In the present embodiment, the thickness of the resin package 5 other than the part where the lenses 5a and 5b are formed is, for example, about 0.3 mm. The resin package 5 may be configured to have translucency with respect to light of most wavelengths.

次に、光通信モジュールＡの作用について説明する。   Next, the operation of the optical communication module A will be described.

本実施形態によれば、受光素子３と樹脂パッケージ５とは、複数の凹部３ｂと樹脂パッケージ５のうちこれらの凹部３ｂに入り込む部分とが互いに噛み合うように接合されている。これにより、受光素子３と樹脂パッケージ５との接合力を高めることが可能である。したがって、たとえば光通信モジュールＡが実装されるときに熱応力が生じても、受光素子３が樹脂パッケージ５および基板１から剥離することを抑制可能であり、光通信モジュールＡの通信を確実に行うことができる。   According to this embodiment, the light receiving element 3 and the resin package 5 are joined so that the plurality of recesses 3b and portions of the resin package 5 that enter these recesses 3b mesh with each other. Thereby, it is possible to increase the bonding force between the light receiving element 3 and the resin package 5. Therefore, for example, even if thermal stress is generated when the optical communication module A is mounted, it is possible to suppress the light receiving element 3 from being peeled off from the resin package 5 and the substrate 1, and the communication of the optical communication module A is reliably performed. be able to.

本発明に係る光通信モジュールは、上述した実施形態に限定されるものではない。本発明に係る光通信モジュールの各部の具体的な構成は、種々に設計変更自在である。   The optical communication module according to the present invention is not limited to the above-described embodiment. The specific configuration of each part of the optical communication module according to the present invention can be modified in various ways.

本発明で言う凹部は、断面円形状のものに限定されず、たとえば断面矩形状のものであってもよい。発光素子および受光素子としては、赤外線を発光もしくは受光可能なものに限定されず、可視光をはじめとする様々な波長の光を発光もしくは受光可能なものを用いても良い。つまり、光通信モジュールとしては、赤外線データ通信モジュールに限定されず、たとえば可視光を用いた通信方式のものであっても良い。   The concave portion referred to in the present invention is not limited to a circular cross section, and may be, for example, a rectangular cross section. The light emitting element and the light receiving element are not limited to those capable of emitting or receiving infrared rays, and may be those capable of emitting or receiving light of various wavelengths including visible light. That is, the optical communication module is not limited to the infrared data communication module, and may be, for example, a communication system using visible light.

本発明に係る光通信モジュールの一例を示す断面図である。It is sectional drawing which shows an example of the optical communication module which concerns on this invention. 図１に示す光通信モジュールに用いられる受光素子を示す底面図である。It is a bottom view which shows the light receiving element used for the optical communication module shown in FIG. 従来の光通信モジュールの一例を示す断面図である。It is sectional drawing which shows an example of the conventional optical communication module.

符号の説明Explanation of symbols

Ａ 光通信モジュール
１ 基板
１ａ 貫通孔
２ 発光素子
３ 受光素子
３ａ 受光面
３ｂ 凹部
４ 駆動ＩＣ
５ 樹脂パッケージ
５ａ，５ｂ レンズ A Optical communication module 1 Substrate 1a Through hole 2 Light emitting element 3 Light receiving element 3a Light receiving surface 3b Recess 4 Drive IC
5 Resin package 5a, 5b Lens

Claims (1)

基板と、
上記基板に搭載された発光素子と、
受光面を有しており、かつ上記基板に搭載された受光素子と、
上記発光素子および受光素子を覆う樹脂パッケージと、
を備える光通信モジュールであって、
上記基板には、貫通孔が形成されており、
上記受光素子は、上記貫通孔の少なくとも一部を覆っており、
上記受光素子のうち上記受光面と反対側の部分には、複数の凹部が形成されており、
上記樹脂パッケージの一部は、上記複数の凹部を覆っていることを特徴とする、光通信モジュール。 A substrate,
A light emitting device mounted on the substrate;
A light receiving element having a light receiving surface and mounted on the substrate;
A resin package covering the light emitting element and the light receiving element;
An optical communication module comprising:
A through hole is formed in the substrate,
The light receiving element covers at least a part of the through hole,
A plurality of recesses are formed in a portion of the light receiving element opposite to the light receiving surface,
An optical communication module, wherein a part of the resin package covers the plurality of recesses.
JP2007059830A 2007-03-09 2007-03-09 Optical communication module Pending JP2008226968A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102537721A (en) * 2010-11-24 2012-07-04 Lg伊诺特有限公司 Lighting module and lighting apparatus comprising the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102537721A (en) * 2010-11-24 2012-07-04 Lg伊诺特有限公司 Lighting module and lighting apparatus comprising the same
CN102537721B (en) * 2010-11-24 2016-12-21 Lg伊诺特有限公司 Lighting module and the illuminator including this lighting module

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