JP2019220672A - Method of manufacturing semiconductor device - Google Patents

Abstract

To provide a method of manufacturing a semiconductor device in which a light-transmissive member and a package can be bonded to each other with high alignment accuracy.SOLUTION: A method of manufacturing a semiconductor device includes sealing a semiconductor laser element disposed in a recess of a package by covering the recess with a light-transmissive member. The method includes: a solder ball forming step of forming a plurality of solder balls at intervals on a surface of the package surrounding the recess where the semiconductor laser element is provided, or on a surface of the light-transmissive member facing the surface; a pre-securing step of bringing the surface of the light-transmissive member or the surface of the package, into contact with an upper surface of the solder balls in a softened state such that an air passage communicating with the inside of the recess is formed between the solder balls, to perform pre-securing; and a bonding step of reducing a pressure in the recess via the air passage, and thereafter, in the state in which a gas for sealing is injected, heating and pressing the light-transmissive member and the package, to melt the solder balls and bond the light-transmissive member and the package.SELECTED DRAWING: Figure 4

Description

  The present disclosure relates to a method for manufacturing a semiconductor device.

  Patent Literature 1 discloses an optical module in which a substrate on which a photoelectric conversion element (for example, a semiconductor laser or a photodiode) is mounted, and a package hermetically sealed by solder bonding in an inert atmosphere.

JP 2007-324303 A

  However, Patent Literature 1 describes that a package and a substrate are joined. However, when joining is performed in a substituted atmosphere without vacuuming, moisture, gas, and the like remain on the package surface, the substrate surface, and the like. . On the other hand, if the evacuation is performed, since the bonding is performed in the vacuum chamber, it is considered difficult to bond the two with high positional accuracy.

  Then, an object of the present invention is to provide a manufacturing method of a semiconductor device which can join a translucent member and a package with good positional accuracy.

In order to solve the above problems, in a method for manufacturing a semiconductor device according to an embodiment of the present invention, a semiconductor laser element provided in a concave portion of a package is sealed by covering the concave portion with a light transmitting member. A method of manufacturing a semiconductor device, comprising:
A solder ball forming step of forming a plurality of solder balls at intervals on the surface of the package around the recess provided with the semiconductor laser element, or on the surface of the translucent member facing the surface,
A temporary fixing step of temporarily fixing the surface of the translucent member or the surface of the package in contact with the upper surface of the softened solder ball so that an airway communicating with the inside of the concave portion is formed between the solder balls; ,
The inside of the recess is depressurized through the airway, and after the depressurization is performed, the sealing ball is injected, and then the light transmitting member and the package are heated and pressed to melt the solder ball, thereby melting the solder ball. A joining step of joining an optical member and the package.

  According to the method for manufacturing a semiconductor device of one embodiment of the present invention, it is possible to provide a semiconductor device capable of joining a light transmitting member and a package with high positional accuracy.

FIG. 4 is a perspective view schematically showing a die bonding step in the method for manufacturing a semiconductor device according to the first embodiment of the present invention. FIG. 5 is a perspective view schematically showing a wire bonding step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 4 is a perspective view schematically showing a solder ball forming step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 5 is a perspective view schematically showing a temporary fixing step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 2 is a perspective view schematically showing a bonding step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 2 is a perspective view schematically showing an individualization step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 2 is a perspective view showing a light-emitting device that has been singulated in the method for manufacturing a semiconductor device according to the first embodiment. FIG. 4 is a perspective view schematically showing a wiring board mounting step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 4 is a perspective view schematically showing a collimating lens mounting step in the method for manufacturing a semiconductor device of the first embodiment. FIG. 14 is a top view of a package of the semiconductor device of the second embodiment. FIG. 9 is a top view of a light-transmitting member and a wavelength conversion member of Embodiment 2. FIG. 6 is a top view of the semiconductor device according to the second embodiment. FIG. 14 is a cross-sectional view schematically showing a bonding step in the method for manufacturing a semiconductor device of the second embodiment. FIG. 14 is a cross-sectional view schematically showing a bonding step in the method for manufacturing a semiconductor device of the second embodiment.

Hereinafter, a method for manufacturing a semiconductor device according to an embodiment of the present invention will be described with reference to the drawings. The method for manufacturing a semiconductor device according to the embodiment is a method for manufacturing a semiconductor device that includes hermetically sealing a semiconductor laser element provided in a concave portion of a package by covering the concave portion with a translucent member.

<First embodiment>
Hereinafter, a method for manufacturing the semiconductor device according to the first embodiment will be described in detail.
In the following description, an example of manufacturing a semiconductor device including three semiconductor laser elements 1, 2, 3 will be described. However, the manufacturing method according to the first embodiment is not limited to the method using three semiconductor laser elements 1, 2, 3, and may be any method including at least one semiconductor laser element.

In the method for manufacturing a semiconductor device according to the first embodiment, first, the package 10, the semiconductor laser elements 1, 2, 3, and the light transmitting member 20 are prepared.
(1) Preparation of Package 10 Here, a collective substrate 100 on which a plurality of packages 10 are provided in a collective state is prepared. As shown in FIG. 1, the collective substrate 100 includes recesses 10 r in regions corresponding to the respective packages 10 (hereinafter, simply referred to as packages even when in the collective state). Positive and negative wiring electrodes to which the electrodes of the semiconductor laser element are connected are provided inside the concave portion 10r, and the wiring electrodes are provided on the lower surface on the opposite side of the concave portion 10r in each package 10. Connected to terminal electrodes. Further, in each package 10, a bonding metal film 10m is provided around the recess 10r. Here, the collective substrate 100 is preferably made of, for example, ceramics having high thermal conductivity in order to efficiently radiate the heat generated by the semiconductor laser device. Examples of the ceramic include aluminum oxide, aluminum nitride, silicon nitride, and silicon carbide. Metals such as Cu, W, and Au can be used for the wiring electrodes and the external terminal electrodes. Au or the like can be used for the bonding metal film 10m. In addition, cuts for singulation are provided in the collective substrate 100 in advance.

(2) Preparation of Semiconductor Laser Devices 1, 2, and 3 As semiconductor laser devices, for example, three types of semiconductor laser devices 1, 2, and 3 of RGB (red, green, and blue) are prepared. The semiconductor laser device 1 is, for example, a red-emitting laser diode (LD) device having an emission peak wavelength in a range of 605 nm to 750 nm. Examples of the red light emitting LD element include an element containing an InAlGaP-based or GaAs-based semiconductor. It is preferable to use an element having two or more waveguide regions as a red light emitting LD element. Thereby, heat generated by the laser oscillation can be dispersed to the plurality of waveguide regions, so that a decrease in output due to the heat can be suppressed.

  The semiconductor laser device 2 is, for example, a green light emitting LD device having a light emission peak wavelength in a range of 495 nm to 570 nm. As the green light-emitting LD element, a GaN-based semiconductor, for example, an element containing at least one of GaN, InGaN, and AlGaN can be used.

  The semiconductor laser device 3 is, for example, a blue light emitting LD device having a light emission peak wavelength in the range of 420 nm to 494 nm. As the blue light emitting LD element, a GaN-based semiconductor, for example, an element containing at least one of GaN, InGaN, and AlGaN can be used.

(3) Mounting of Semiconductor Laser Devices 1, 2, and 3 on Submounts 4a and 4b Here, the semiconductor laser devices 1, 2, and 3 prepared above are mounted on the submounts 4a and 4b. Specifically, the semiconductor laser element 1 which is a GaAs-based laser diode, for example, is mounted alone on the submount 4a. The semiconductor laser element 2 and the semiconductor laser element 3, which are GaN-based laser diodes, are mounted on the submount 4b together with a protection element 8 such as a Zener diode. By connecting the semiconductor laser element 2 and the semiconductor laser element 3 in parallel with the protection element 8 respectively, it is possible to prevent a certain voltage or more from being applied to the semiconductor laser elements 2 and 3.
In this manner, whether or not the semiconductor laser elements 1, 2, 3 are mounted on the bottom surface of the recess 10r via the submounts 4a, 4b is optional, but the bottom surface of the recess 10r is supported via the submounts 4a, 4b. In this case, the distance from the light emitting point on the light emitting end face of the semiconductor laser element to the bottom surface of the concave portion 10r can be increased by the thickness of the submounts 4a and 4b. Thereby, the light radiated from the LD element can be efficiently applied to the light reflecting member 60. Each submount 4a, 4b is provided with a wiring electrode, and each semiconductor laser element is fixed on each submount 4a, 4b by a bonding member such as AuSn.

As the submounts 4a and 4b, for example, aluminum nitride or silicon carbide can be used.

Here, the reason that the semiconductor laser element 1 is mounted alone on the submount 4a and the semiconductor laser elements 2 and 3 are mounted on the submount 4b together with the protection element 8 is that the crystal such as GaAs is a GaN-based crystal. This is because the material has less crystal defects and has a relatively high electrostatic breakdown voltage.
In the following description, a laser unit including a submount 4a, 4b and a semiconductor laser element mounted on the submount 4a, 4b is referred to as a laser unit.

(4) Preparation of Light Reflecting Member 6 As shown in FIG. 1, the light reflecting member 6 has, for example, a substantially triangular prism shape having three side surfaces and one of the side surfaces as a reflecting surface. A member that reflects light and emits laser light in a predetermined direction. The light reflecting member 6 is provided on the bottom surface of the concave portion 10r so that the laser light of each semiconductor laser element is incident on the reflecting surface at a predetermined angle. By using the light reflecting member 6, light traveling parallel to the bottom surface of the recess 10r can be changed in a direction perpendicular to the bottom surface of the recess 10r. Thereby, the emission direction of the laser light of each semiconductor laser element can be made parallel to the bottom surface of the recess 10r, and the light emitting device can be made thin.

  As the light reflecting member 6, a member in which a reflective film is formed on a base material, or a member in which a base material itself is formed of a metal having high reflectivity without providing a reflective film, can be used. As the base material, a material such as quartz or glass such as BK7, and a relatively heat-resistant material such as Si can be used. A metal may be used as the base material. As the reflective film, a metal having a high reflectivity, a dielectric multilayer film, or the like can be used. The reflection film may be formed only on the light reflection surface. The light reflecting member 6 may be separated into a plurality of light reflecting members. For example, a plurality of light reflecting members may be used corresponding to the semiconductor laser elements 1, 2, and 3, respectively.

(5) Preparation of translucent member 20 The translucent member 20 is a translucent member that transmits laser light, and covers the semiconductor laser device provided in the recess 10r of the package 10 to cover the semiconductor laser device. Is hermetically sealed. The translucent member 20 has a bonding metal film 20m provided on the outer peripheral portion of the lower surface, and the bonding metal film 20m is attached to the bonding metal film 10m provided around the concave portion 10r of the package 10 by a solder ball 15m. And is fixed to the package 10. As the translucent member 20, for example, a member in which glass is provided with the bonding metal film 20m or a member in which sapphire is provided with the bonding metal film 20m can be used. Among them, it is preferable to use sapphire provided with a bonding metal film 20m. For example, sapphire has relatively high strength and is not easily damaged, so that the airtight reliability in the concave portion 10r in which the semiconductor laser element is arranged can be increased. In addition, since sapphire has a higher thermal conductivity than glass, heat is easily transmitted during a temporary bonding step and a main bonding step described later, and the solder balls are easily softened and melted.

  In the method for manufacturing a semiconductor device according to the first embodiment, a light emitting device is manufactured by incorporating the prepared laser unit, the light reflecting member, the light transmitting member 20 and the like into the prepared package 10 through the following steps.

1. In the mounting step, as shown in FIG. 1, the laser units 1u, 2u, 3u and the light reflecting member 6 are mounted on the bottom surface of the concave portion 10r of each package 10 of the collective substrate 100, respectively. Here, for example, each member is mounted as follows. The laser units 1u, 2u and 3u are arranged such that the laser beams emitted from the semiconductor laser elements 1, 2 and 3 are emitted in parallel to each other and in parallel to the bottom surface of the recess 10r. The light reflecting member 6 is arranged so that the laser light emitted from the semiconductor laser elements 1, 2, 3 is reflected upward by the reflecting surface 6a. In addition, AuSn, Ag particle paste, Au particle paste, or the like can be used as the bonding member for mounting.

2. Wire Bonding Step In the wire bonding step, as shown in FIG. 2, the wiring electrodes of the laser units 1u, 2u, 3u and the wiring electrodes in the recess 10r are connected by wires 7.

3. Solder Ball Forming Step In the solder ball forming step, as shown in FIG. 3, a plurality of AuSn solder balls 15 are arranged at intervals on the bonding metal film 10m on the upper surface of the package 10. The solder balls 15 use solder such as AuSn. The solder ball 15 can be formed, for example, with a diameter in the range of 80 to 400 μm. The diameter of the solder ball 15 and the interval between the adjacent solder balls 15 are appropriately set so that an appropriate airway is secured in a temporary fixing step described later, and the hermetic sealing can be reliably performed in the main bonding step. The diameter of the solder ball 15 is preferably in the range of 100 to 200 μm. When the diameter of the solder ball is less than 100 μm, for example, when joining a flat package having an inferior flatness such as a ceramic package, the volume of the solder ball is not sufficient and the unevenness of the joining surface is sufficiently filled. Is difficult. When the diameter of the solder ball is 200 μm or more, the volume of the solder ball is in an excessive state, and the solder ball is unnecessarily expanded at the time of joining. Further, the interval between adjacent solder balls 15 is preferably set in a range of 100 to 1000 μm. The above range is determined depending on the diameter of the solder ball. When the diameter of the solder ball is within the above range, the solder ball in the molten state spreads without excess and deficiency in the joining step, and effective joining is obtained. The shape of the solder ball 15 is not limited to a spherical shape, but may be an elliptical sphere, a hemisphere, or an elliptical hemisphere. Here, the diameter of the solder ball 15 refers to the maximum diameter of the solder ball 15. When the diameter of the solder ball cannot be formed in the above range, a plurality of solder balls 15 may be formed at the same position. In this case, the solder balls 15 can be formed in a desired volume. Therefore, an airway is appropriately secured in a temporary fixing process described later, and airtight sealing can be reliably performed in the main joining process. At this time, the shape and / or diameter of the overlapping solder balls 15 may be different from the case where one solder ball is formed.

  In the above-described solder ball forming step, an example has been described in which a plurality of solder balls 15 are formed at intervals on the surface of the package 10 around the concave portion 10r provided with the semiconductor laser element. However, the present invention is not limited to this, and a plurality of solder balls may be formed at intervals on the bonding metal film 20 m provided on the outer peripheral portion of the translucent member 20 by, for example, turning upside down. In this case, in a temporary fixing step described later, the bonding metal film 10m provided on the surface of the package 10 is temporarily fixed by being brought into contact with the upper surface of the solder ball 15 in a softened state.

  As described above, the plurality of solder balls 15 may be formed on the surface of the package 10 or may be formed on the surface of the translucent member 20. It is preferable to form the conductive member 20 on a member having a higher thermal conductivity. In this way, heat is easily transmitted to the solder balls 15 in the following temporary fixing step and joining step. For example, when the package 10 is mainly made of AlN ceramics and the translucent member 20 is mainly made of sapphire, the solder balls 15 are formed on the surface of the package 10.

4. Bonding Step The bonding step is as follows: (1) The surface of the light transmitting member 20 (the surface of the bonding metal film 20 m provided on the lower surface) is formed such that an airway communicating with the recess 10 r is formed between the solder balls 15. A temporary fixing step of temporarily fixing the solder ball 15 by contacting the upper surface of the solder ball 15 in a softened state; and (2) depressurizing the inside of the recess 10 r through an airway formed between the solder balls 15, and sealing the gas after depressurizing. In which the light-transmissive member 20 and the package 10 are heated and pressed in a state of being injected. In the main joining step, the solder balls 15 are melted and the light transmitting member 20 and the package 10 are joined.
Here, the heating and pressing does not limit the order of the timing of heating and the timing of pressing, and pressing in a heated state after heating, and heating in a pressed state after pressing, Includes all simultaneous heating and pressing.
Hereinafter, the joining step will be described more specifically.

(1) Temporary Fixing Step In the temporary fixing step, the translucent member 20 is positioned so that the bonding metal film 20 m formed on the outer periphery of the lower surface of the translucent member 20 faces the plurality of solder balls 15. And temporarily fixed on the concave portion 10r. In the temporary fixing step, for example, the translucent member 20 is pressed onto the solder ball at a temperature lower than the melting point of the solder ball. Thereby, joining can be easily performed. At the time of joining in the temporary fixing step, the heating temperature of the package 10 is preferably lower than the heating temperature of the translucent member 20. With this configuration, it is possible to reduce the deterioration of the electrodes provided on the package 10 and the laser units 1u, 2u, and 3 due to thermal damage, and to suppress an increase in the drive voltage of the laser unit. Further, the temperature of the translucent member 20 having a lower thermal conductivity than the package can be increased in a short time. For example, when AnSn having a melting point of 285 ° C. is used as the solder ball 15, the heating temperature of the translucent member 20 is set in the range of 230 ° C. to 270 ° C., and the heating temperature of the package 10 is 180 ° C. to 220 ° C. Set to a range. The thermocompression conditions such as the heating temperature, pressure, and time during thermocompression bonding are appropriately set in consideration of the shape and diameter of the solder balls 15 and the spacing between adjacent solder balls 15.

  In this temporary fixing step, for example, the solder ball 15 is heated to a temperature lower than the melting point through the light transmitting member 20 and, if necessary, the package 10 using the die bonder or the like to soften the solder ball 15. Let it. Thus, the translucent member 20 is brought into contact with the softened upper surface of the solder ball 15 and temporarily fixed so that an airway communicating with the inside of the recess 10 r is formed between the solder balls 15. The temporary fixing step is performed so that adjacent solder balls do not come into contact with each other when the solder balls are softened. Thereby, an airway communicating with the inside of the concave portion 10r can be reliably secured. The temporary fixing step can be performed in the air, and does not need to be performed in a vacuum chamber as in the main bonding step described below. Compared to the case where the temporary bonding is performed in the vacuum chamber or the case where the temporary bonding is not performed, the temporary bonding can be performed with high positional accuracy when the temporary bonding is performed outside the vacuum chamber. Further, by temporarily holding the package 10 outside the vacuum, it is possible to prevent the translucent member 20 and the package 10 from shifting when the package 10 is transported.

(2) Main Bonding Step In the main bonding step, first, the package 10 (the collective substrate 100) on which the translucent member 20 is temporarily fixed is carried into a vacuum chamber. Next, by reducing the pressure in the vacuum chamber, the pressure in the concave portion 10 r covered with the translucent member 20 is reduced through the airway formed between the solder balls 15. After the inside of the concave portion 10r is depressurized, the sealing gas is injected into the concave portion 10r by introducing a sealing gas into the vacuum chamber. Then, the light transmitting member 20 and the package 10 are heated and pressed while the sealing gas is injected into the recess 10r.
For the heating and pressing, for example, a hot press having an upper mold (first pressing body) and a lower mold (second pressing body) capable of adjusting the heating temperature is arranged in a vacuum chamber capable of reducing pressure, This is used, for example, as follows.

  First, as schematically shown in FIG. 5, between the upper mold 31 and the lower mold 32 in the vacuum chamber, the collective substrate 100 on which the translucent member 20 is mounted on each of the recesses 10r is placed. Deploy.

  Next, the upper mold 31 and the lower mold 32 are brought into contact with the collective substrate 100 from above and below such that the airway formed between the solder balls 15 is not blocked. In this state, the pressure in the vacuum chamber is reduced. After the pressure is reduced, a sealing gas is introduced into the vacuum chamber. As a result, the sealing gas is injected into the concave portion 10r covered with the translucent member 20 through the airway formed between the solder balls 15. As the sealing gas, for example, a mixed gas containing dry air (dry air) and helium gas can be used. When a mixed gas containing dry air and helium gas is used, the ratio of oxygen and nitrogen and helium gas constituting dry air is, for example, 20% oxygen, 60% nitrogen, and 20% helium.

Next, with the sealing gas injected, the light transmitting member 20 and the package 10 are heated and pressed by the upper mold 31 and the lower mold 32.
At this time, the heating temperature of the upper mold 31 and the lower mold 32 is set so that, for example, the solder balls 15 have a temperature equal to or higher than the melting point. At the time of heating, for example, it is preferable that the temperature of the lower mold 32 be lower than the temperature of the upper mold 31 so that the heating temperature of the package 10 is lower than the heating temperature of the translucent member 20. That is, the upper mold 31 (first pressing body) heated at the first temperature is brought into contact with the translucent member 20 and pressed, and the lower mold heated at the second temperature lower than the first temperature is pressed on the package 10 side. It is preferable that the mold 32 (second pressing body) is brought into contact with and pressed to thereby melt the solder ball 15 and join the translucent member 20 and the package 10. With this configuration, it is possible to reduce deterioration of the electrodes provided on the package 10 and the laser units 1u, 2u, and 3u due to thermal damage, and to suppress an increase in drive voltage of the laser unit.
For example, the package 10 is heated and pressed so as to have a temperature lower than the melting point of the bonding member used when mounting the semiconductor laser element in the recess 10r, so that the mounting position of the semiconductor laser element from a predetermined position is reduced. Deviation can be suppressed.
In the case where the semiconductor laser device is bonded on the submounts 4a and 4b by the first bonding member, and the submounts 4a and 4b are mounted in the recess 10r by the second bonding member, for example, a package may be used. 10 is heated and pressed at a temperature lower than the melting point of the first joining member and the melting point of the second joining member. As a result, a deviation of the mounting position of the semiconductor laser element from a predetermined position can be suppressed. In the main bonding step, for example, the temperature of the upper mold 31 (first pressing body) is in the range of 280 ° C to 400 ° C, and the temperature of the lower mold 32 (second pressing body) is in the range of 100 ° C to 200 ° C. Preferably, there is. Further, it is preferable that the load at the time of pressing be in a range of 10 N or more and 100 N or less per 1 cm ² .

In the above joining step, a buffer sheet having heat resistance and flexibility that can withstand the heating temperature is disposed between the upper mold 31 (first pressing body) and the translucent member 20, and the translucent member 20 is formed. It is preferable to heat and press through a buffer sheet. In this manner, the light-transmissive members 20 can be uniformly pressed to the entirety, and can be hermetically sealed. Hermetic sealing can be determined, for example, by the amount of dry air leakage. If the amount of dry air leak is 10 ⁻⁸ Pa · m ³ / s or less, it is considered that the airtight sealing is sufficiently performed. In addition, by using the buffer sheet, the contact thermal resistance between the upper mold 31 (first pressing body) and the translucent member 20 can be reduced, that is, the heat conduction can be improved, so that the translucent member can be obtained. 20 can be heated efficiently.
Here, for example, a carbon sheet can be used as the buffer sheet. A carbon sheet is suitable because it has high heat resistance and has flexibility and compression restorability in a wide temperature range. Further, the carbon sheet is also suitable in that, for example, there is no generation of gas contaminating the sealing gas as compared with other elastic members such as rubber.

In the above joining step, the lower mold 32 (the second mold) is used instead of or in addition to the buffer sheet disposed between the upper mold 31 (first pressing body) and the translucent member 20. A buffer sheet having heat resistance and flexibility to withstand the heating temperature may be arranged between the pressing body and the package 10.
When the buffer sheet is arranged between the lower mold 32 (second pressing body) and the package 10, the contact state on the bottom surface side of the package 10 becomes good, and heat can be efficiently radiated. Thus, for example, when the heating temperature of the lower mold 32 is lower than the heating temperature of the upper mold 31, the heat of the upper mold 31 can be efficiently released to the lower mold, and the package 10 Temperature rise can be suppressed. As the buffer sheet on the lower mold 32 side, a carbon sheet can be used in the same manner as the buffer sheet on the upper mold 31 side.

5. Individualization Step As described above, the light emitting devices manufactured in the aggregated state as described above are divided into element units using, for example, a breaking blade 40, as shown in FIG. As described above, since the cuts for singulation are provided in advance on the collective substrate, the singulation can be performed by pressing the break blade 40 against the cuts. In this singulation process, a break blade 40 is pressed from the package side. In this way, it is possible to suppress the light transmitting member from being damaged as compared with a case where the breaking blade 40 is pressed from the light transmitting member 20 side. FIG. 7 shows a light-emitting device that has been separated.
As described above, it is possible to manufacture a light emitting device in which the semiconductor laser element provided in the concave portion 10r is hermetically sealed by the translucent member 20.

  According to the method for manufacturing a semiconductor device of Embodiment 1 configured as described above, the temporary fixing step is provided before the main bonding step, so that the temporary fixing step can be performed outside the vacuum chamber. Thereby, the translucent member and the package can be joined with high positional accuracy. If the translucent member and the package are positioned in a vacuum chamber without performing the temporary fixing step, the inside of the vacuum chamber is observed through an observation window provided in the vacuum chamber to observe the inside of the vacuum chamber. Then, since the observation range is limited, it may be difficult to detect an accurate position. In addition, the translucent member can be easily arranged using a general-purpose die bonder device or the like.

  In the method of manufacturing the semiconductor device according to the first embodiment, in the final bonding step, the pressure in the vacuum chamber is reduced, so that the inside of the concave portion 10r covered with the translucent member 20 through the airway formed between the solder balls 15 is formed. Is decompressed, and a sealing gas is injected after decompression. This makes it possible to remove the moisture and gas components attached to the package 10 by using the reduced pressure. Therefore, compared with the case where the temporary fixing is not performed, it is not necessary to remove the attached moisture and the attached gas components by heating at a temperature of, for example, 200 ° C. for a long time, thereby suppressing the deterioration of the semiconductor laser element due to the long-time heating. it can.

  Further, according to the method of manufacturing the semiconductor device of the first embodiment, since the hermetic sealing can be performed collectively using the collective substrate 100, the cost is lower than that of the light emitting device configured using the CAN package. Can be manufactured.

  In the first embodiment, a method for manufacturing a semiconductor device has been described with an example of manufacturing a light emitting device. However, the method for manufacturing a semiconductor device according to the first embodiment is not limited to the method for manufacturing a light-emitting device, and can be applied to other semiconductor devices requiring hermetic sealing. Even when applied to another semiconductor device, the translucent member and the package can be joined with high positional accuracy, similarly to the method of manufacturing the semiconductor device of the first embodiment. Further, the semiconductor device can be manufactured at low cost.

  The semiconductor device described in the first embodiment may include other members such as a wiring board and a collimator lens. The light-emitting device 50 can emit light from each semiconductor laser element as parallel light by providing a collimating lens on the translucent member 20 as described below, for example.

  For example, a light emitting device having a collimating lens can be manufactured through the following steps using the light emitting device 50 manufactured by the manufacturing method of the first embodiment.

6. Wiring Board Mounting Step Here, as shown in FIG. 8, the package 10 of the light emitting device 50 manufactured by the manufacturing method of the first embodiment is mounted on the wiring board 110. As shown in FIG. 8, the wiring substrate 110 is made of, for example, ceramics, and has a metal film 112 which functions as an alignment mark when the package 10 is mounted on the wiring substrate 110. And a metal film 114 for fixing the heat radiating surface of the package 10 and the substrate 111 to each other. The substrate 111 is preferably made of the same material as the package 10. For example, when the package 10 is made of ceramic, the substrate 111 is made of the same ceramic material.

7. Next, a collimating lens 70 is mounted on the translucent member 20, as shown in FIG. Adhesives 90 are applied to the four corners of the upper surface of the translucent member 20, and the collimating lens 70 is positioned and fixed. The collimator lens 70 can be made of glass such as borosilicate glass. The collimator lens 70 includes a first lens unit 71 that emits laser light emitted from the semiconductor laser element 1 in a predetermined direction, and a second lens unit 72 that emits laser light emitted from the semiconductor laser element 2 in a predetermined direction. A third lens portion 73 that emits laser light emitted from the semiconductor laser element 3 in a predetermined direction is provided side by side. The non-lens portion 74 is provided so as to surround the first lens portion 71, the second lens portion 72, and the third lens portion 73.
A light emitting device having a collimating lens manufactured as described below can emit light from each semiconductor laser element as parallel light.

  Further, the method of manufacturing a semiconductor device is not limited to the above-described method. When airtight sealing is performed without performing evacuation, for example, the following method can be used.

<Embodiment 2>
The method for manufacturing a semiconductor device according to the second embodiment is a method for manufacturing a semiconductor device including sealing a semiconductor laser element provided in a concave portion of a package by covering the concave portion with a light transmitting member. A ball forming step and a joining step are included. The solder ball forming step is a step of forming a plurality of solder balls at intervals on the surface of the package around the concave portion provided with the semiconductor laser element or on the surface of the light-transmitting member facing the surface. is there. In the joining step, the package and the translucent member are separated from each other in a container having an air supply port for supplying the sealing gas and an exhaust port for exhausting the gas, or an airway is formed between the solder balls. And a sealing gas is supplied to the container, and the package or the translucent member on which the solder balls are formed is heated to press at least one of the package and the translucent member. This is a step of melting the solder balls and joining the surface of the light transmitting member and the surface of the package.

  According to the method for manufacturing a semiconductor device of the second embodiment, since a vacuum chamber is not used, it is possible to provide a semiconductor device capable of joining a light transmitting member and a package with high positional accuracy.

  Hereinafter, a method for manufacturing the semiconductor device according to the second embodiment will be described in detail. However, items substantially the same as those in the first embodiment may be appropriately omitted.

(1) Package Preparation The package 10 will be described with reference to FIG.
Except for the following, the preparation of the package is substantially the same as that described in the first embodiment.
Here, the package 10 is prepared. The package 10 may be singulated in advance, or may be an aggregate substrate 100 on which a plurality of packages 10 are provided in an aggregate state.
The package 10 has an outer peripheral portion 10n for arranging the translucent member 20, a surface to which the translucent member 20 is joined, and a concave portion 10r in which the semiconductor laser unit is provided. The surface of the outer peripheral portion 10n is higher than the surface to which the translucent member 20 is joined. The surface to which the translucent member 20 is joined has a shape having corners. Among the corners of the package surface surrounding the recess 10r and to which the translucent member 20 is joined, the radius of curvature of the corner on the side of the recess 10r is larger than the radius of curvature of the corner on the side of the outer periphery 10n.

If the material of the package 10 is different from the material of the translucent member 20, the linear expansion coefficients of the two may not match. In such a case, there is a possibility that the bonding material for bonding the two may receive thermal stress due to a difference in linear expansion coefficient between the package 10 and the translucent member 20, and may be damaged.
In the second embodiment, as shown in FIG. 10, among the corners of the package surface surrounding the recess 10r and to which the translucent member 20 is joined, the radius of curvature of the corner on the recess 10r side is equal to the outer peripheral portion 10n. Preferably, it is larger than the radius of curvature of the side corner. By setting the curvature of the concave portion as described above, the possibility that the bonding material for bonding the package 10 and the translucent member 20 is damaged by thermal stress can be reduced. When it is desired to reduce the size of the whole package, it is preferable that the shape of the corner on the outer peripheral side depends on the shape of the light transmitting member 20. In the case of a material in which the process of giving a curvature to the corner of the translucent member 20 is complicated, it is difficult to sufficiently increase the radius of curvature on the outer peripheral side. However, by setting the radius of curvature of the corner on the concave side as described above, the concentration of thermal stress can be reduced. An example of such a translucent member 20 is sapphire.
In addition, by adopting the package shape as described above, it becomes possible to arrange more solder balls in the corners than in the region other than the corners. By arranging many solder balls 15, the adhesion between the package 10 and the translucent member 20 is increased, and the sealing gas is less likely to leak.

(2) Preparation of Semiconductor Laser Element As the semiconductor laser element to be prepared, the same material and the same emission peak wavelength as those of the first embodiment can be used. The present invention is not limited to the semiconductor laser elements 1, 2, 3 of the three colors of RGB. Any one of RGB or two colors may be used. Further, a plurality of any one color may be provided. In the second embodiment, a case where a blue-emitting semiconductor laser device is used will be described.

(3) Mounting the semiconductor laser element on the submount and (4) Preparing the light reflecting member The number and emission color of the semiconductor laser elements to be mounted can be changed as appropriate to form a laser unit. It is substantially the same as the matter described.

(5) Preparation of Translucent Member The translucent member 20 will be described with reference to FIG. 11A.
The preparation of the translucent member is substantially the same as that described in the first embodiment, except for the matters described below.
When the blue semiconductor laser element 3 is used, as shown in FIG. 11A, the light transmitting member 20 may further include a wavelength conversion member 21 to make the light emitted from the semiconductor device white. The wavelength conversion member 21 is excited by the laser light oscillated from the semiconductor laser element 3 and emits light having a different wavelength from the laser light. For example, the wavelength conversion member can be formed of a single-crystal or polycrystalline phosphor, a composite of a phosphor and a reflector, or a sintered body formed by molding and firing a phosphor powder and a reflector. As the phosphor 21p, a so-called YAG phosphor in which the activator is cerium and the matrix is yttrium aluminum garnet (hereinafter, referred to as YAG) can be used. As the reflective material 21r, aluminum oxide, aluminum nitride, YAG containing no activator, yttrium oxide, or the like can be used.

  In the method for manufacturing a semiconductor device according to the second embodiment, a light emitting device is manufactured by incorporating the prepared laser unit 3u, the light reflecting member 6, the light transmitting member 20, and the like into the prepared package 10 through the following steps. .

1. 1. mounting process; 2. wire bonding step and Solder Ball Forming Step The mounting step, wire bonding step, and solder ball forming step are substantially the same as those described in the first embodiment. The solder ball 15 may be provided on either the surface around the concave portion of the package 10 or the surface of the translucent member 20 facing the surface. In the second embodiment, the solder ball 15 is provided on the surface around the concave portion of the package 10. The case will be described.

4. Bonding Step In the bonding step in the second embodiment, the surface of the light transmitting member and the surface of the package are bonded by the molten solder ball. At this time, the package and the translucent member are integrated into a container having an air supply port for supplying the sealing gas and an exhaust port for discharging the gas so that an airway is formed between the solder balls. The package and the light transmitting member are heated while the package or the light transmitting member on which the solder balls are formed is pressed, and at least one of the package and the light transmitting member is pressed.
Here, the phrase “accommodating in a separated state” includes all cases of accommodating the package and the translucent member at the same time and cases of accommodating them at different timings. In the case of housing at different timings, either the package or the light transmitting member may be housed first.
In addition, the order of heating the package or the translucent member on which the solder balls are formed and pressing at least one of the package and the translucent member may be first.

Hereinafter, the bonding process will be described with reference to FIGS. 12A and 12B.
First, a container having at least the supply port 123in and the exhaust port 123out is arranged on the stage 122 having a heater. The container 120 and the stage 122 may be formed integrally. In this case, these members can be regarded as one container collectively.
The sealing gas is supplied through the gas line 123 and is introduced into the container 120 from the air supply port 123in. Since the container 120 has an exhaust port 123out, the sealing gas is exhausted to the outside of the container through the exhaust port 123out. At this time, the gas containing moisture originally filled in the container is also exhausted. Thus, the package can be hermetically sealed with the translucent member in a state where the inside of the container 120 is filled with the dried gas, that is, in a state where the inside of the concave portion 10r of the package 10 is filled with the dried gas. As a result, the dew point of the semiconductor device is reduced as compared with the case where the semiconductor device is sealed with a gas containing moisture.
It is preferable that the sealing gas be continuously supplied before the package 10 is introduced into the container 120 until the bonding step is completed. Thereby, the atmosphere in the container 120 can be more reliably replaced with the sealing gas.
The flow rate of the sealing gas is preferably 5 liters per minute or more. The gas in the container 120 can be sufficiently replaced, and the dew point of the semiconductor device decreases. The upper limit of the temperature of the sealing gas may be lower than the melting point of the solder ball 15. For example, when the material of the solder ball 15 is AuSn, the temperature of the sealing gas is 280 ° C. or less.
As in the first embodiment, a mixed gas containing dry air and helium gas can be used as the sealing gas.

  Further, it is preferable that the temperature of the stage 122 is lower than the melting point of the solder ball 15 and is warmed to near the melting point of the solder ball 15. It is warmed until the temperature difference from the melting point becomes, for example, 30 ° C. or less. Preferably it is 20 degrees C or less, More preferably, it is 10 degrees C or less. By heating the stage 122 in advance, when the package 10 on which the solder balls 15 are formed is placed on the stage 122, the temperature of the package 10 is shorter than when the package 10 is placed and then heated. Thus, the temperature can reach the melting point of the solder ball 15 or more. As a result, the lead time can be reduced.

  Next, the package 10 on which the solder balls 15 are formed and the translucent member 20 are respectively housed in the container 120. As shown in FIG. 12B, the surface of the package 10 and the surface of the translucent member 20 are joined via the solder balls 15 by pressing the translucent member 20 using the pressing body 124. However, the package 10 and the translucent member 20 may be accommodated before the sealing gas is supplied into the container 120, or may be accommodated after the gas is supplied. Further, the translucent member 20 may be introduced into the container 120 in a state where the translucent member 20 is attached to the pressing body 124 and joined to the package 10. The load applied by the pressing body 124 is preferably 1 N or more and 200 N or less. More preferably, it is 1N or more and 100N or less. Since the inside of the container is filled with the sealing gas, there is a possibility that the solder balls 15 may not be sufficiently widened just by placing the translucent member 20 on the package 10. By applying the load of the above degree, it can be expanded to a range sufficient for joining.

  In the above joining step, an example has been described in which the plurality of solder balls 15 are formed at intervals on the surface of the package to which the translucent member 20 is joined, surrounding the recess 10r. However, the present invention is not limited to this. For example, a plurality of solder balls may be formed at intervals on the bonding metal film 20 m provided on the outer peripheral portion of the translucent member 20. In this case, it is conceivable that the translucent member 20 is disposed on the stage 122 and the package 10 is joined by pressing the package 10 using the pressing body 124.

5. Individualization Step The individualization step is a step performed when the collective substrate 100 is prepared in the package preparation step. For example, this is performed as in the first embodiment. If individualization has been performed before the joining step, the individualization step need not be performed here.

  According to the method of manufacturing a semiconductor device of Embodiment 2 configured as described above, since the vacuum chamber is not used, the translucent member and the package can be joined with high positional accuracy.

  According to the method for manufacturing a semiconductor device of the second embodiment, the atmosphere inside the container is replaced with a sealing gas to reduce the amount of moisture contained in the semiconductor device even without vacuuming. Thus, the light emitting device and the light transmitting member can be hermetically sealed.

  FIG. 11B is a top view of the light emitting device 50 in which the package 10 and the translucent member 20 including the wavelength conversion member 21 are joined. The laser light oscillated from the semiconductor laser is raised by the light reflecting member 6, becomes white light through the phosphor 21p of the wavelength conversion member 21, and is taken out of the light emitting device.

1, 2, 3 Semiconductor laser element 1u, 2u, 3u Laser unit 4a, 4b Submount 6 Light reflecting member 6a Reflecting surface 7 Wire 8 Protective element 10 Package 10m, 20m Bonding metal film 10n Outer peripheral portion 10r Concave portion 15 Solder ball 15a Bonding material 20 Translucent member 21 Wavelength conversion member 21r Reflector 21p Phosphor 31 Upper die 32 Lower die 50 Light emitting device 70 Collimating lens 71 First lens part 72 Second lens part 73 Third lens part 74 Non-lens part 90 Adhesive 100 Assembly board 110 Wiring board 111 Substrate 112 Metal film 113 Wiring electrode 114 Metal film 120 Container 122 Stage 123 Gas line 123 in Inlet port 123 out Exhaust port 124 Press body

Claims (14)

A method for manufacturing a semiconductor device, comprising sealing a semiconductor laser element provided in a concave portion of a package by covering the concave portion with a translucent member,
A solder ball forming step of forming a plurality of solder balls at intervals on the surface of the package around the recess provided with the semiconductor laser element, or on the surface of the translucent member facing the surface,
A temporary fixing step of temporarily fixing the surface of the translucent member or the surface of the package in contact with the upper surface of the softened solder ball so that an airway communicating with the inside of the concave portion is formed between the solder balls; ,
The inside of the recess is depressurized through the airway, and in a state where the sealing gas is injected after the depressurization, the solder ball is melted by heating and pressing the translucent member and the package. A method of manufacturing a semiconductor device, comprising: a bonding step of bonding a light transmitting member and the package.   2. The method according to claim 1, wherein, in the bonding step, a heating temperature of the package is lower than a heating temperature of the translucent member. 3.   3. The method of manufacturing a semiconductor device according to claim 2, wherein, in the bonding step, the translucent member is heated to a temperature equal to or higher than a melting point of the solder ball.   In the joining step, a first pressing body heated at a first temperature is brought into contact with the translucent member, and a second pressing body heated at a second temperature is brought into contact with the package, so that the first pressing body and the second pressing body are contacted with each other. 4. The manufacturing of the semiconductor device according to claim 3, wherein the solder ball is melted by pressing the pressing body to join the light transmitting member and the package, and the second temperature is lower than the first temperature. 5. Method.   5. In the joining step, an elastically deformable buffer sheet is arranged between the first pressing body and the light transmitting member, and the light transmitting member is heated and pressed via the buffer sheet. 6. 13. The method for manufacturing a semiconductor device according to item 5.   6. The semiconductor according to claim 4, wherein in the joining step, an elastically deformable buffer sheet is arranged between the second pressing body and the package, and the package is heated and pressed via the buffer sheet. 7. Device manufacturing method.   The method of manufacturing a semiconductor device according to claim 1, wherein the package is a ceramic package.   The method of manufacturing a semiconductor device according to claim 1, wherein the solder ball is an AuSn ball.   9. The method of manufacturing a semiconductor device according to claim 1, wherein, in the temporary fixing step, the solder ball is softened at a temperature lower than a melting point of the solder ball.   The semiconductor laser device includes a first semiconductor laser device that emits red laser light, a second semiconductor laser device that emits green laser light, and a third semiconductor laser device that emits blue laser light. 10. The method for manufacturing a semiconductor device according to any one of 1 to 9. Before the solder ball forming step, the method includes an element mounting step of mounting the semiconductor laser element in the recess by a first bonding member,
The method of manufacturing a semiconductor device according to claim 1, wherein in the bonding step, the package is heated and pressed at a temperature lower than a melting point of the first bonding member. In the element mounting step, a first mounting step of bonding the semiconductor laser element on a submount by the first bonding member and a submount in which the semiconductor laser element is bonded are mounted in the recess by a second bonding member. Including a second mounting step,
The method of manufacturing a semiconductor device according to claim 11, wherein in the bonding step, the package is heated and pressed at a temperature lower than a melting point of the first bonding member and a melting point of the first bonding member. A method for manufacturing a semiconductor device, comprising sealing a semiconductor laser element provided in a concave portion of a package by covering the concave portion with a translucent member,
A solder ball forming step of forming a plurality of solder balls at intervals on the surface of the package around the recess provided with the semiconductor laser element, or on the surface of the translucent member facing the surface,
In a container having an air supply port for supplying a sealing gas and an exhaust port for exhausting the air, in a state where the package and the translucent member are separated from each other, or such that an airway is formed between the solder balls. While housed in an integrated state, the sealing gas is supplied to the container, and the package or the translucent member on which the solder balls are formed is heated, and the package and the translucent member are heated. A bonding step of melting at least one of the solder balls to bond the surface of the translucent member and the surface of the package by pressing at least one of them.   A method of manufacturing a semiconductor device, wherein a supply flow rate of the sealing gas is 5 liters per minute or more.

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