Semiconductor device

The present invention provides a semiconductor device having a structure which is suitable for reduction in thickness and weight.The semiconductor device 1 comprises a housing 12 which has the recess 24 in the front surface 14, the pair of lead electrodes 20 which have the distal ends 34 exposed in the recess 24, protrude from the external surface of the housing 12 and are bent along the bottom surface 16 of the housing 12, and a semiconductor element 36 which is housed in the recess 24 and is electrically connected to the pair of lead electrodes 20. The housing 12 has the grooves 30 which are formed on the pair of side surfaces 18 which adjoin the front surface 14 and the bottom surface 16 on the right and left sides so as to penetrate the housing 12 from the top surface 28 toward the bottom surface 16 of the housing 12. The grooves 30 preferably have width substantially equal to the thickness of the lead electrode 20. The grooves 30 are more preferably formed to be flush with the distal ends 34 of the lead electrode 20.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates a light emitting device using a semiconductor light emitting element, and a light receiving device used in an optical sensor or the like, and, more particularly, to a low-profile light emitting device used as the backlight of a liquid crystal display.

2. Description of the Related Art

In recent years, the backlight of a liquid crystal display employs a surface-emitting light source comprising a low-profile light emitting device and an optical guide which spreads the light emitted by the light emitting device. One among the light emitting devices used in such applications is a low-profile light emitting device comprising a light emitting diode disposed in a flat housing made of a resin (refer to, for example, Japanese Unexamined Patent Publication (Kokai) No. 2004-363537). The resin housing has such a constitution as a protrusion is provided on an elongated light emitting surface and a recess which receives the protrusion is formed on the end face of the optical guide, so as to improve the precision of positioning with respect to the optical guide.

Japanese Unexamined Patent Publication (Kokai) No. 2004-363537 discloses such a constitution as a hanger lead is provided in a part of a lead frame, so as to support the housing on the lead frame during the process of manufacturing the light emitting device. A method of supporting the housing by using a typical hanger lead will be described below with reference to the accompanying drawing.

FIG. 10(A)shows an example of lead frame102having a housing106. Supported on the lead frame102by the hanger lead100is the housing106which has a flat shape and incorporates a pair of lead electrodes104.FIG. 10(B)is a partially enlarged view of the structure of supporting the housing106by the hanger lead100. As can be seen from this drawing, a distal end108of the hanger lead100is embedded in a side surface110of the housing106. The housing106is supported on the lead frame102, by forming the support structure comprising the housing106and the hanger lead100on the side surfaces110on both sides of the housing106. The housing106is supported in such a manner as the principal surface thereof is disposed at right angles to the front surface of the lead frame102.

FIGS. 11(A) and 11(B)are perspective views of a light emitting device constituted from the lead frame102provided with the housing106shown inFIGS. 10(A) and 10(B). A method of forming the light emitting device114shown inFIG. 11from the lead frame102provided with the housing106shown inFIGS. 10(A) and 10(B)will now be described. First, an LED is mounted in a recess112of the housing106. As distal end portions of a pair of lead electrodes104are exposed in the recess112, electrical continuity is established in advance between the two distal end portions and positive or negative electrode of the LED, respectively, by die bonding or wire bonding. The recess112is filled with a translucent resin so as to seal the LED with the resin116in the housing106. Then the lead frame102is cut off along dashed line X. The lead electrode104which is cut off the lead frame102is bent along the bottom surface of the housing106and is further bent along the side surface. During the bending operation, the housing106is held in a predetermined posture by the hanger lead100. Last, the hanger lead100is bent in the state of supporting the housing106, and the hanger lead100is pulled out of the side surface110of the housing106, thereby obtaining the light emitting device114. As a result, the depression118in which the distal end portions108of the hanger lead100were embedded is left to remain in the side surfaces110of the light emitting device114as shown inFIGS. 11(A) and 11(B). The low-profile light emitting device114manufactured in this way is mounted with the side of the lead electrode104facing downward. The light emitting device114is combined with an optical guide with the side of the recess112serving as the window for light emission, so as to constitute a surface emitting light source for liquid crystal display of mobile phone or mobile computer.

While the light emitting device disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2004-363537 has a thickness small enough to suit the application to plane light source, recently there is a demand for light emitting device of further smaller thickness. However, decreasing the thickness of the light emitting device having the constitution disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2004-363537 gives rise to some problems.

For example, when a low-profile light emitting device is manufactured by using lead frame provided with hanger lead, it is necessary to decrease the width of the hanger lead which results in a decrease in strength of the hanger lead. This increases the possibility of such troubles to occur as the hanger lead is subjected to torsional deformation when the lead frame provided with hanger lead is transported, thus causing the housing to tilt. Also during the operation to bend the lead electrode104, stress acting on the housing106causes the hanger lead100to twist, thus resulting in tilting of the housing106. Tilting of the housing makes it impossible to die-bond the semiconductor element, thus giving rise to the possibility of faulty products.

The low-profile light emitting device is prone to troubles during positioning also in case it is mounted by a conventional chip mounter. A chip mounter which is commonly used has a suction nozzle for transferring the chip. The light emitting device is held on the top surface thereof by the suction nozzle by means of negative pressure, and is transferred to the mounting position. The light emitting device transferred by the suction nozzle is precisely positioned at the predetermined position of a sub-mount, and is placed at the predetermined position by breaking the vacuum in the suction nozzle. However, in case the semiconductor device is thinner and lighter in weight than the conventional one, position of the semiconductor device may be displaced by a slight movement of air caused by breaking the vacuum, even when the semiconductor device and the sub-mount are aligned precisely before breaking the vacuum of the suction nozzle.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a semiconductor device of a structure suitable for reduction in thickness and in weight, particularly to provide a semiconductor device which allows it to (1) stably hold the housing which is secured onto the lead frame during the LO manufacturing process, and (2) improve the positioning accuracy when mounting the product thus manufactured.

The present invention is a semiconductor device comprising a housing which has a recess in the front surface thereof, a pair of lead electrodes which have distal ends exposed in the recess, protrude from the external surface of the housing and are bent along the bottom surface of the housing, and a semiconductor element which is housed in the recess and is electrically connected to the pair of lead electrodes, wherein the housing has grooves which penetrate the housing from the top surface toward the bottom surface of the housing and are formed on the pair of side surfaces adjoining the front surface and the bottom surface on right and left sides thereof.

The grooves of the semiconductor device preferably have width substantially equal to the thickness of the lead electrode.

It is further preferable that the grooves are formed flush with the distal end of the lead electrode.

The present invention is a method for manufacturing a light emitting device which comprises a housing having a recess in the front surface thereof, a pair of lead electrodes which have distal ends exposed in the recess, protrude from the external surface of the housing and are bent along the bottom surface of the housing, and a semiconductor element which is housed in the recess and is electrically connected to the pair of lead electrodes, the method comprising the steps of preparing the lead frame constituted from a metal sheet having a plurality of openings and a pattern of the lead frame formed therein so as to protrude toward the inside of each of the openings, exposing the distal ends of the lead electrode in the recess of the housing and forming the grooves in the side surfaces of the housing by means of circumference of the opening formed in the lead frame, bending the pair of lead electrodes, which protrude from the housing, along the external wall surface of the housing while holding the housing on the lead frame by cutting off the pair of lead electrodes from the lead frame and fitting the opening formed in the lead frame into the groove, and releasing the housing from the lead frame.

With the semiconductor device of the present invention, it is made possible to improve the accuracy of positioning during mounting, too, by taking advantage of the grooves formed in the side surfaces of the housing so as to penetrate therethrough. When a guide bar which fits in the groove is provided on the suction nozzle of the chip mounter which transfers the semiconductor device, for example, displacement of the semiconductor device caused by breaking the vacuum after the transfer of the semiconductor device can be suppressed. A guide pin which fits into the groove may also be provided on the circuit board whereon the device is to be mounted. Since the groove penetrates from the top through the bottom, the guide bar or the guide pin can be easily inserted and pulled out either from the top or the bottom. The guide bar and the guide pin may have simple rod shape. In case the light emitting device is used in combination with an optical component such as optical guide, for example, the light emitting device and the optical component can be easily positioned by providing a positioning member at a predetermined position of the optical component which fits into the groove of the light emitting device.

With the semiconductor device described above, in case the groove has a width substantially equal to the thickness of the lead electrode, there may a case of supporting the housing by fitting a part of the lead frame into the groove. Since the groove penetrates from the top through the bottom, the housing can be engaged with the circumference of the opening formed in the lead frame which has higher strength, not on a hanger lead of thin band shape as in the prior art. This enables it to suppress the housing which is secured onto the lead frame from tilting, even when the light emitting device is made thinner. At this time, the circumference of the opening may be processed so as to match the groove. In case the groove is not formed flush with the lead frame, for example, the circumference of the opening may be adjusted in shape so as to achieve the same height as the groove.

It is more preferable to form the groove of the housing flush with distal end of the lead electrode, namely in the same surface as the main body of the lead frame before cutting off the housing, since this eliminates the need to process the circumference of the opening formed in the lead frame as described above. The housing can be held directly onto the lead frame by fitting an appropriate portion of the circumference of the opening formed in the lead frame into the groove without processing.

According to the method of manufacturing a semiconductor device of the present invention, the housing is secured onto the circumference of the opening formed in the lead frame for manufacturing the semiconductor described above, and therefore the housing can be suppressed from tilting during the manufacturing process. As the portion which has been holding the lead frame interposed therebetween remains as the groove in the semiconductor device thus obtained, the groove can be used to prevent displacement during mounting and help alignment with the optical component. Thus the manufacturing method of the present invention makes it possible to prevent the housing secured onto the lead frame from tilting and causing defects, and manufacture the semiconductor device which can be easily mounted.

DESCRIPTION OF REFERENCE NUMERALS

10Semiconductor device12Housing14Front surface of housing16Bottom surface of housing18Side surface of housing20Lead electrode22Back surface24Recess of housing28Top surface of housing30Groove32Lead frame34Distal ends (a, b) of lead electrode36Semiconductor element40Opening42Circumference of opening48Notch50Step52Corner (Edge on top surface side)54Corner (Edge on bottom surface side)

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The light emitting device10shown inFIG. 1comprises a housing12of flat shape and a lead electrode20which is bent from a bottom surface16along a side surface18of the housing12. Front surface of the housing12serves as a light emitting surface14, with a recess24formed so as to open in the light emitting surface14and extends toward the back surface22. The opening of the recess24constitutes a window for light emission. The recess24is filled with a translucent resin26so as to seal a semiconductor light emitting element (not shown) which is mounted in the recess24. A groove30is formed in the side surface18of the housing12to extend in parallel to the light emitting surface14. The groove30penetrates from the top surface28through the bottom surface16of the housing12. The housing12serves as a support member which supports a semiconductor1, light emitting device and the distal end of the lead electrode20, and also as a protective member which protects the semiconductor light emitting element and the metal wire used in wire bonding from the external environment.

In this specification, the expression of “housing of flat shape” means that the housing has a height smaller in comparison to width and depth thereof.

The groove30is formed flush with the lead electrode20which is provided in the recess24, as will be described in detail later, and the groove30has a width substantially equal to the thickness of the lead electrode20. Therefore in the process of manufacturing the light emitting device10, the groove serves as a holding member which holds the portion which surrounds the opening formed in the lead frame, namely the circumference of the opening (referred to as opening circumference in the present specification), so as to secure the housing12with respect to the lead frame. As a result, the housing can be suppressed from tilting when transferring the lead frame provided with the housing and when cutting and forming the lead frame.

The groove30can be used in positioning when mounting the light emitting device by inserting a guide bar or a guide pin into the groove30. Since the groove30penetrates from the top through the bottom, the guide bar or the guide pin can be easily inserted and pulled out either from the top or the bottom of the housing12. Since the groove30opens also in the side surface18, such a guide member that enters into the groove30through the side surface18can be used, in addition to a rod-shaped guide member such as the guide bar or the guide pin. Thus positioning can be done by means of guide members of various forms, since the light emitting device10has the groove30which penetrates therethrough. Various methods of positioning will be described below as examples.

FIG. 2shows an example of the process of mounting the light emitting device10by means of the chip mounter. The suction nozzle120sucks up the housing12of the light emitting device10on the top surface28thereof, while two guide bars122supported by the chip mounter are inserted into the grooves30formed in the side surfaces18on both sides of the housing12. When the guide bars122are inserted into the grooves30, the light emitting device10can be moved up and down sliding along the guide bar122.

With the light emitting device10being guided by the guide bars122and positioned at a predetermined position of the sub-mount, breaking the vacuum in the suction nozzle120does not cause the light emitting device10to be displaced over the surface due to the guide bar, and being capable of sliding up and down so as to settle on the sub-mount. As a result, displacement does not occur when vacuum is broken, even when the light emitting device10is made with smaller weight and smaller thickness.

FIG. 3shows an example of mounting of the light emitting device10on the sub-mount124. The sub-mount124has a guide pin126at a position corresponding to the position where the light emitting device10is mounted. The light emitting device10can be prevented from being displaced from the predetermined position over the surface or tilting from the predetermined direction, by fitting the two guide pins126in the grooves30formed in the side surfaces18located on the right and left of the light emitting device10.

Since the groove30penetrates the housing12, the groove30and the guide pin126can be easily fitted together. That is, after transferring the light emitting device10to a position above the sub-mount124, it suffices to align the bottom end of the groove30and the top end of the guide pin126and lowering the light emitting device10vertically toward the sub-mount124.

FIG. 4shows an example of surface emitting light source which combines the light emitting device10and an optical guide130. The optical guide130has two hooks132on the end134. The hooks132are formed so as to lock onto the grooves30formed in the side surfaces18of the housing12, thus enabling it to achieve accurate relative positioning of the light emitting device10and an optical guide130.

Since the groove30penetrates the housing, the light emitting device10can be positioned easily and accurately simply by aligning the grooves30and the hooks132and inserting the light emitting device10between the two hooks132.

InFIG. 1, it is preferable to form notches or steps in a pair of corners (ridges on top surface side)52where the top surface28and the side surfaces18of the housing12intersect, so that the top end of the groove30is located below the top surface28of the housing12.

The grooves30formed in the side surfaces18of the housing12are formed at the same time as the housing12is molded. At this time, small burrs46tend to be formed on the edges of the groove30. In case the end of the groove30is flush with the top surface28of the housing12, the burrs46increase the thickness of the housing12, and therefore increase the thickness of the light emitting device10. In the case of a low-profile light emitting device, in particular, it is not desirable that the thickness increases due to the burrs46. While the burrs46may be removed after being generated, it is not desirable since it increases the manufacturing process. When notches or steps (notches48are shown inFIG. 1) are formed in the ridges52on top surface side so that the burrs generated on the top end of the groove30do not protrude beyond the top surface28, and therefore it is made possible to prevent the height of the light emitting device from increasing due to the burrs46generated on the top end of the groove30after the molding process.

It is preferable to form the notches or steps in the pair of corners (ridges on bottom surface side)54where the bottom surface16and the side surfaces18of the housing12intersect, so that the bottom end of the groove30is located above the bottom surface16of the housing12. The light emitting device10of the present invention is mounted with the bottom surface16serving as the mounting surface. Therefore, when the burrs46generated on the bottom end of the groove30protrude beyond the bottom surface16, not only the thickness of the light emitting device10increases but also the burrs46touch the mounting substrate and cause displacement in the mounting position of the light emitting device10and/or tilt the light emitting device10. By providing the notches or steps (steps are shown inFIG. 1) in the ridges on bottom surface side so that the burrs46generated on the bottom end of the groove30do not protrude beyond the bottom surface, it is made possible to prevent such problems from occurring as displacement of the mounting position of the light emitting device10when it is mounted on the circuit board.

As described above, the light emitting device of the present invention has a structure which can improve the mounting accuracy despite small thickness and small weight. As a result, use of the light emitting device in a thin surface emission light source makes it possible to maintain a high mounting accuracy comparable to that of the light emitting device of the prior art, even when the thickness of the housing of the semiconductor device of the present invention is decreased to 1.5 mm or less. The light emitting device of the present invention may also be formed in a shape suitable to a surface emission light source such that width of the housing is 3 times as the thickness thereof.

In the light emitting device10of the present invention, it is preferable to fill the recess24of the housing12with a translucent resin in which case the semiconductor light emitting element secured in the recess24of the housing12can be protected from the external environment. In case it is desired to emit light of a color different from that of the semiconductor light emitting element by means of the light emitting device10, a fluorescent material may be mixed in the translucent resin so as to efficiently convert the wavelength.

The method of manufacturing the light emitting device10of the present invention will now be described with reference toFIGS. 5 to 9.

First, a metal sheet is punched through and is coated with metallic plating on the surface thereof, to make the lead frame32. The lead frame32has a pair of lead electrodes20(20aand20b), of which distal ends34(34a,34b) oppose each other via a gap. Typically, a number of pairs of the lead electrodes20are formed on one metal sheet.

Then as shown inFIG. 5(A), the lead frame32is disposed between molding dies70,72which are separated into upper and lower parts for molding the housing so as interpose the lead frame32between the upper and lower molding dies70,72. At this time, the distal ends34(34a,34b) of the pair of lead electrodes20and a part of circumference42of the opening40formed in the lead frame32are disposed in a cavity62of the molding dies70,72which has the shape of housing12.

Then as shown inFIG. 5(B), a molding material68is poured into the cavity62of the molding dies70,72through a material charging gate64of the lower molding die72. The upper molding die70has a protrusion66corresponding to the recess24of the housing12formed thereon. When the molding material68is poured while the protrusion66is in contact with the top surface of distal end34of the lead electrode20, it is made possible to keep the molding material from being deposited on the top surface of the distal end34and expose the distal end34on the inside of the recess24of the housing12.

In this example, the distal ends34of the lead electrodes are completely exposed on the inside of the recess24of the housing12, however it is not necessary to completely expose these members. For example, a part of the lead electrode may be exposed in the recess by disposing the distal ends34of the lead electrodes directly below the bottom of the recess24(namely having the distal ends34of the lead electrodes covered by the molding material68of the housing12) and forming a hole in the bottom of the recess24. Then the light emitting device10of the present invention can be formed by establishing electrical continuity between the semiconductor light emitting element and the lead electrode through the hole.

When the molding material68has hardened in the molding dies70,72as shown inFIG. 5(C), the lower molding die72is removed as shown inFIG. 5(D)and then the upper molding die70is removed. When the upper molding die70is removed, the housing12can be easily taken out by pushing out release pins60, which are inserted slidably into the upper molding die70, in the direction of P.

Through the series of steps shown inFIG. 5, the lead frame32provided with the housing12shown inFIG. 6is obtained. A part of the circumference42of the opening40formed in the lead frame32cuts into the side surfaces18of the housing12which has been molded, so that the penetrating groove30is formed. The groove30enables the housing12to be supported on the lead frame32throughout the manufacturing process of the light emitting device10. The housing12has, on the circumferential surface thereof, a thin linear ridge-like protrusion called the parting line formed along the border of the upper and lower molding dies. When the housing is molded by disposing the dies as shown inFIG. 5, the parting line of the housing12thus molded and the groove30are located substantially in the same plane.

While a single housing12is formed in the case shown inFIG. 6, typically a number (3 in column by 2 in row, totaling 6 in the case shown) of the housings12,12. . . are formed in one lead frame32as shown inFIG. 7. When a number of housings12are formed, all the housings12can be formed at the same time by using the molding dies70,72which have a number of cavities62for the housings and pouring the molding material into the cavities62at the same time.

InFIGS. 6 and 7, the process of forming the light emitting device10by using the lead frame32provided with the housing12will now be described with reference toFIG. 8andFIG. 9.

First, the inside of the recess24of the housing12will be described below with reference toFIG. 8.

The housing12has a pair of lead electrodes20(20aand20b) which penetrate from the bottom surface16of the housing12to the recess24. Exposed on the inside of the recess24are the pair of distal ends34of the lead electrodes20(34a,34b) which oppose each other. As described above, the housing12is supported on the lead frame32by the circumference42of the opening40formed in the lead frame32and the lead electrodes20.

It is preferable to form the recess24of the housing12in such a shape that makes it easier for the light emitted by the semiconductor light emitting element36mounted on the inside of the recess24to emerge on the side of the light emitting surface14of the housing12. For example, a tapered shape which gradually expands toward the light emitting surface14is preferably used.

A procedure of securing the semiconductor light emitting element36on the housing12will now be described.

The semiconductor light emitting element36is die-bonded onto the distal end34aof the lead electrode20ain the recess24of the housing12, then the positive electrode and the negative electrode of the semiconductor light emitting element36are connected to the distal ends34a,34bof the lead electrodes20a,20b, respectively, by wire bonding with the metal wire38. The semiconductor light emitting element36may be selected from light emitting diodes which emit light of various wavelengths. In order to constitute a surface emission light source for white light in combination with an optical guide, in particular, a nitride semiconductor light emitting element which emits blue light and a fluorescent material which absorbs blue light and emits yellow light may be preferably combined.

Then recess24of the housing12is sealed with the translucent resin26for the protection of the semiconductor light emitting element36from the environment. The recess24of the housing12is filled with the translucent resin26so as to cover the semiconductor light emitting element36or the metal wire38, and the resin is hardened.

Then the lead electrodes20are cut off from the lead frame32at the position indicated by dashed line X inFIG. 8and are bent along the external wall surface of the housing12(called the cut-forming process) thereby to form the connection terminals of J-bend shape. Since the side surfaces18of the housing12are secured onto a part of the circumference42of the opening40formed in the lead frame32, the lead electrodes20can be bent at the same time for the plurality of housings12formed on one lead frame32, thus improving the efficiency of manufacturing the light emitting device10. Particularly, according to the present invention, since the housing12is supported by the circumference42of the opening40which has a high strength, the housing12can be held in the predetermined posture even when the bending operation applies a stress to the housing12.

Bending operation of the lead electrodes20is carried out by bending the narrow portion of the lead electrode20either toward the light emitting surface14or toward the back surface22. Then a portion of the wider portion of the lead electrode20, which extends beyond the side surface18of the housing12, is bent along the side surface18.

The narrow portion of the lead electrode20is preferably bent toward the back surface22as in the light emitting surface14shown inFIG. 1, for roughly two reasons described below.

The first reason is the effect of suppressing solder or eutectic layer from spreading onto the light emitting surface14when mounting the light emitting device10. In the light emitting device10of the present invention, the bottom surface16is used as a mounting surface and the lead electrode20is electrically connected to the circuit board by means of solder or eutectic layer. Therefore, when the lead electrode20is bent toward the light emitting surface14, solder bump or eutectic layer is located near the light emitting surface14. Thus in case the accuracy of mounting is not proper and too much solder or molten eutectic metal is applied, the solder or eutectic metal may spread onto the light emitting surface14. When the lead electrode20is bent toward the back surface22, the light emitting device10which has been mounted is less likely to be adversely affected and the rate of defect occurrence can be decreased.

The second reason is the heat dissipation from the light emitting device10. The housing12has smaller thickness in a portion where the lead electrodes20are disposed, thus keeping the thickness of the light emitting device10from increasing due to the addition of the lead electrode20. While heat dissipation from the light emitting device10can be improved by increasing the surface area of the lead electrode20, it requires it to increase the area of the portion of the housing where the thickness is made smaller. When the lead electrode20is bent toward the light emitting surface14, since the area of the portion of the housing where the thickness is made smaller is restricted by the opening of the window of light emission, it is difficult to increase the surface area of the lead electrode20. When the lead electrode20is bent toward the back surface22, in contrast, limitation on the surface area of the portion of the housing of smaller thickness is eliminated. Accordingly, surface area of the lead electrode20can be increased as long as the pair of lead electrodes20are prevented from touching each other, thereby improving the heat dissipation.

When the lead electrodes20have been bent, the housing12is removed from the lead frame32. In the case of the housing supported by the hanger lead of the prior art (refer toFIG. 10), the hanger lead100which is formed in a band shape has low strength and can be easily bent. However, the circumference42of the opening40formed in the lead frame32whereon the housing12is supported in the present invention has a high strength and cannot be directly bent. Accordingly, in the present invention, strength of the circumference42of the opening40is decreased by cutting out the portion near the circumference42before removing the housing12.FIG. 9shows an example of the cutting out operation.

InFIG. 9(A)andFIG. 9(B), the circumference42of the opening40which support the housing12is left to remain in a band or L shape after forming a cutout44of the lead frame32. By cutting out in this way, the circumference42of the opening40is formed in a configuration similar to that of the hanger lead100shown inFIG. 10, and can be easily bent.

As another form, the circumference42of the opening40may be left in the shape of rectangular opening as shown inFIG. 9(C). In this form, the housing12may be removed by pulling the circumference42in the direction indicated by the arrow, thereby easily deforming the circumference42.

The light emitting device10made as described above is prone to less defects which would be caused by the reduction in thickness and weight, and can be handled easily during the manufacturing process and mounting on the sub-mount.

Components of the light emitting device10will now be described in detail.

While there is no restriction on the material used to form the lead electrode20as long as it has electrical conductivity, it is preferable to use iron, steel, copper-clad iron, copper-clad tin, copper, gold, silver-plated aluminum, iron, copper or the like.

The housing12may be formed from a thermoplastic resin such as liquid crystal polymer, polyphthalamide resin or polybutylene phthalate (PBT). It is particularly preferable to use a semi-crystalline polymer resin which includes crystal having a high melting point such as polyphthalamide resin, for the reason of high surface energy and good bonding with the translucent resin26which fills in the recess of the housing12. Use of this material suppresses the housing and the translucent resin26from being separated along the interface therebetween when the translucent resin26is cooled so as to harden. A white pigment such as titanium oxide may be added to the molding material so that the housing12can efficiently reflect the light emitted by the semiconductor light emitting element36.

The metal wire38used in wire bonding may be made of, for example, a metal such as gold, copper, platinum or aluminum or an alloy thereof.

The translucent resin26is preferably one that has high weatherability such as silicone resin, epoxy resin, urea resin, fluorocarbon resin or a hybrid resin which includes at least one of the former. Instead of the translucent resin26, an inorganic material having light fastness such as glass or silica gel.

In case a blue light emitting diode and a fluorescent material are combined to make the light emitting device10which emits white light, particles of the fluorescent material may be dispersed in the translucent resin26. For the fluorescent material, a rare earth-based fluorescent material which absorbs blue light and emits yellow light (for example, YAG fluorescent material) is preferably used.

The semiconductor device of the present invention can be used in a device which requires an extremely thin light emitting device such as the backlight of a liquid crystal display.