KR20030088249A - Method of Fabricating Package of semiconductor laser devices - Google Patents

Abstract

PURPOSE: A semiconductor optical device package and a manufacturing method thereof are provided to reduce the size of a product by using a flip chip bonding and a silicon hole to manufacture an optical device package. CONSTITUTION: A solder bump(14) is formed on an electrode pad of an optical device(11), which is provided with a waveguide or a light-receiving region(12) and one more than electrode pad on a surface thereof. A silicon substrate(15) includes a metal wiring layer(16) deposited and patterned with a metal thin film, a protective film(17) on the metal wiring layer(16), a flip chip bonding band patterned with the protective film(17) selectively, a substrate metal pad, and a silicon hole(20). A solder ball(21) is an electrical intermediate and adhered to the substrate metal pad on the silicon substrate(15). After the optical device(11) and an optical fiber(22) are formed in line through the silicon hole(20) formed on the silicon substrate(15), the optical fiber(22) is fixed on a silicon substrate(15) by adhesives(23).

Description

Semiconductor optical device package and manufacturing method therefor {Method of Fabricating Package of semiconductor laser devices}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor optical device package using flip chip bonding and silicon holes in a package of an optical device having an optical waveguide or an optical receiving active region on a surface thereof, and a method of manufacturing the same.

In general, in the semiconductor optical device package, since the optical waveguide of the optical device is on the side, the conventional technique for aligning the optical fiber is a passive alignment type optical coupling using silicon V-groove and flip chip bonding.

The passive alignment method using flip chip bonding and silicon V-groove is known as a promising technology that can reduce the size of the optical device package and reduce the manufacturing cost, compared to the conventional thiogan package using the active wire bonding method. .

In addition, the optical device package using the flip chip bonding method can manually align the optical device and the optical fiber by the self-alignment property by the surface tension of the molten solder during flip chip bonding.

Referring to a conventional optical coupling device using flip chip bonding and a silicon V-groove, FIG. 1A illustrates a passive coupling between a semiconductor laser and an optical fiber 5 using a silicon substrate 1 having a silicon V-groove 2 formed therein. 1B is a cross-sectional view taken along line AA ′ of FIG. 1A, and FIG. 1C is a cross-sectional view taken along line B-B ′ of FIG. 1B.

As shown in FIG. 1, a conventional optical device package includes an optical device 3 having a waveguide 4 on a side thereof on a silicon substrate 1 having a silicon V-groove 2 formed by anisotropic etching. It is a method of flip chip bonding and aligning the optical fiber 5 to the silicon V-groove 2 on the silicon substrate 1.

As described above, the optical device package 3 using the conventional flip chip bonding and the silicon V-groove 2 may be applied only to the optical device 3 having the waveguide 4 on the side. Therefore, it is very difficult to apply to a light transmitting element that generates light at the center of the surface or a light receiving element that detects light at the center of the surface.

Even if applicable, there is a need for a structure in which a laser generated in a waveguide on the surface of an optical device reflects 90 degrees toward the optical fiber on the side by adding one or more processes.

When such a structure is applied, optical loss of the laser due to reflection may occur, and the alignment error between the optical device and the optical fiber, which may occur in the existing substrate structure instead of the reflective structure, may increase in the substrate structure in which the laser is reflected.

Therefore, the conventional alignment method using the silicon V-groove 2 is a technique that is difficult to apply to the alignment of the optical element and the optical fiber having a waveguide or receiving active region on the surface of the silicon substrate.

According to the present invention, even when the optical device is difficult to handle due to the small size of the optical device, the package can be implemented in a general / standard size that is easy to handle using the silicon substrate. The present invention provides a general-purpose optical device package which can contribute to optical devices having a waveguide or a light receiving area on a surface thereof.

In addition, the present invention can reduce the manufacturing cost by simplifying the process by the manual alignment between the optical device and the optical fiber through the self alignment of flip chip bonding and the silicon hole formed in the silicon substrate.

In addition, the present invention satisfies the electrical characteristics of the package for high-speed optical devices of 10GPbs or more because the heat and heat transfer through the solder bumps in the optical device package structure using flip chip bonding, so that the heat emission is good It is an object of the present invention to provide a method for manufacturing a semiconductor optical device package.

1 is a diagram illustrating an optical device package using a silicon substrate having a V-groove, which is a conventional technology.

Figure 2 is a process diagram showing a process for forming a solder bump on the optical device having a waveguide or light receiving region on the surface according to the present invention

Figure 3 is a process diagram showing the process of manufacturing a silicon substrate having a repositioning metal layer and silicon holes in accordance with the present invention

4 is a process chart of completing an optical device package by flip-chip bonding an optical device on which a solder bump is formed on a silicon substrate and aligning optical fibers according to the present invention.

5 is a view showing another embodiment of the present invention, a process diagram for forming an optical device package by aligning an optical element and an optical fiber with a silicon substrate having a silicon hole including a control space of the optical fiber

* Explanation of symbols for the main parts of the drawings

1: Silicon Substrate 2: Silicon V-groove

3: optical element 4: waveguide

5: optical fiber 11: optical element

12 waveguide or light receiving region 13 electrode pad

14 solder bump 15 silicon substrate

16 metal wiring layer 17 protective film

18 flip chip real name pad 19 substrate metal pad

20 silicon hole 21 solder ball

22: optical fiber 23: adhesive

24: control space 100: optical device package

Method for manufacturing an optical device package of the present invention for achieving the above object,

Forming a solder bump (14) on the electrode pad (13) of the optical element (11) having a waveguide or light receiving region (12) on the surface and at least one electrode pad (13);

Depositing and patterning a metal thin film on the surface of the silicon substrate 15 to form a metal wiring layer 16;

Applying a protective film (17) to the surface of the metal wiring layer formed on the silicon substrate, and selectively patterning the protective film to form a flip chip bonding pad (18) and a substrate metal pad (19);

Forming a silicon hole (20) on the silicon substrate (15);

Aligning solder bumps (14) formed on the optical device (11) with flip chip bonding pads (18) formed on the silicon substrate (15) to flip-chip bonding the optical devices on the silicon substrate;

Attaching a solder ball (21), which is an electrical medium, to the substrate metal pad (19) formed for electrical connection with an external optical communication system on the silicon substrate (15); And

After aligning the optical element 11 and the optical fiber 22 through the silicon hole 20 formed on the silicon substrate 15, the optical fiber 22 is fixed on the silicon substrate 15 with an adhesive 23 It includes the step of manufacturing the optical device package 100 of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2A, in an optical element 11 having a waveguide or light receiving region 12 and one or more electrode pads 13 on a surface, solder bumps 14 are formed on the electrode pads 13 as shown in FIG. 2B. To form.

The materials used for the solder bumps 14 are eutectic solder (63Sn / 37Pb), high lead solder (90-95Pb / Sn), lead free solder (Sn / Ag, Sn). / Cu, Sn / Zn, Sn / Zn / Bi, Sn / Ag / Cu or Sn / Ag / Bi) may be used any one material.

On the other hand, the process of forming the solder bumps 14, electroplating in a solder plating solution using a thick film photosensitive material or solder bumps by screen printing method using solder paste (solder paste) (14) is formed.

FIG. 3A illustrates a process of depositing a metal thin film on the upper surface of the silicon substrate 15 to be electrically connected between the optical device 11 and an external optical communication system, and then selectively etching to form the metal wiring layer 16.

Sputtered deposition is mainly used as the metal thin film deposition process, and electrolytic or electroless-plating deposition (electroless-plating deposition) may be additionally applied to increase the thickness of the metal film.

In this case, the applied metal wiring layer 16 is formed of at least one or more layers, and the metal used is aluminum or aluminum alloy, titanium or titanium alloy, nickel or nickel alloy, copper or copper alloy, chromium or chromium alloy, gold or gold alloy, or the like. Mainly used.

The following materials can be used. Deposition sequentially looking at the bottom layer first, Al or Al alloy / Ni or Ni alloy, Al or Al alloy / Ni or Ni alloy / Cu or Cu alloy, Al or Al alloy / Ti or Ti alloy / Ni or Ni Alloy / Cu or Cu alloy, Ti or Ti alloy / Ni or Ni alloy, Ti or Ti alloy / Ni or Ni alloy / Cu or Cu alloy, Ti or Ti alloy / Cu or Cu alloy and the like can be used.

In FIG. 3B, a protective film 17 layer is coated on the metal wiring layer 16 and selectively etched to protect the formed metal wiring layer 16 and to make an electrical connection between an external optical communication system, and selectively etch the metal wiring layer 16. A process of forming a flip chip bonding pad 18 and a substrate metal pad 19 for electrical connection with external optical communication is exposed by exposing an upper surface of an arbitrary position.

As the material of the protective layer 17 layer, polyimide (PI), benzocyclobutene (BCB), epoxy resin, silicon resin (Siloxane or Silicone resin), or silicon nitride is used. do.

In the process of selectively etching the passivation layer 17 coated on the metal wiring layer 16, a photoresist may be used or the passivation layer 17 itself may be made of a photosensitive material.

In the process of applying the protective layer 17 material layer, spin coating may be performed by using a coating equipment, or printing or laminating may be used to form the protective layer 17 material layer. It can be prepared by deposition.

3C illustrates a process of forming a silicon hole 20 on the silicon substrate 15 to align the optical fiber 22 with the waveguide or the light receiving region 12 on the optical device 11.

In the process of forming the silicon hole 20 on the silicon substrate 15, the silicon hole 20 may be dry or wet etched using a photosensitive material as a selective etching mask, or sometimes mixed with dry and wet. Can also be used as a wet mixed etch method. This completes the silicon substrate 15 having the flip chip bonding pad 18, the substrate metal pad 19, and the silicon hole 20 formed on the upper surface thereof.

4A illustrates flip chip bonding by aligning the flip chip bonding pads 18 formed on the silicon substrate 15 manufactured as described above and the solder bumps 14 formed on the optical device 11, and then performing the silicon chip 15. And attaching the solder ball 21 to the substrate metal pad 19 formed on the substrate.

In the step of flip chip bonding the optical device 11 on the silicon substrate 15, an appropriate amount of an oxide film removing material called flux is applied to the flip chip bonding pad 18, and the electrode pad of the optical device 11 ( The solder bumps 14 formed on the 13 and the flip chip bonding pads 18 formed on the upper surface of the silicon substrate 15 are aligned to place the optical device 11 on the silicon substrate 15.

At this time, the flux of the material applied on the flip chip bonding pad 18 is tacked so that the flux does not move until the solder bumps 14 are fused.

Then, the temperature is increased by using a reflow process, and the solder bumps 14 on the optical device 11 are self-aligned due to the surface tension of the solder when the solder bumps 14 are fused with the flip chip bonding pads 18. Becomes

In the step of attaching the solder balls 21 to the substrate metal pads 19 on the silicon substrate 15, flux, which is an oxide film removing material, is applied to the substrate metal pads 19, and the solder balls 21 are rippled. Weld using a reflow process.

Materials used for the solder balls 21 are eutectic solder (63Sn / 37Pb), high melting solder (90-95Pb / Sn), lead free solder (Sn / Ag, Sn). / Cu, Sn / Zn, Sn / Zn / Bi, Sn / Ag / Cu or Sn / Ag / Bi) may be used.

In FIG. 4B, the optical wave 22 is inserted into the silicon hole 20 formed on the silicon substrate 15 to align the waveguide or the light receiving region 12 and the optical fiber 22 formed on the surface of the optical element 11 and the adhesive agent. The process of fixing using (23) is shown.

At this time, the optical fiber 22 does not leave the upper surface of the silicon substrate 15 so that the optical fiber 22 does not contact the waveguide or the light receiving region 12 on the optical element 11.

In the step of patterning the upper surface of the metal wiring layer 16 of the silicon substrate 15 with the protective layer 17, the pattern size of the protective layer 17 where the silicon hole 20 is opened is smaller than the diameter of the silicon hole 20. Forming smaller than the diameter of the optical fiber 22 so that the optical fiber 22 does not leave the upper surface of the silicon substrate 15 to facilitate the alignment of the optical fiber 22.

When the waveguides or the light receiving regions 12 of the optical fiber 22 and the optical element 11 are aligned, the optical fiber 22 is fixed to the silicon hole 20 on the silicon substrate 15 with an adhesive 23 to the surface. The optical device package 100 having the waveguide or the light receiving region 12 is completed.

The material of the adhesive 23 which fixes the optical fiber 22 to the silicon hole 20 is manufactured using either a photosensitive or non-photosensitive polymer resin adhesive or a ceramic adhesive containing an adhesive component. .

5 shows another embodiment of the structure of the optical device package 100 of the present invention.

FIG. 5A illustrates that the optical element 11 and the optical fiber 22 are required to be precisely aligned, and then the optical fiber 22 is inserted into the silicon hole 20 so that the active element may be activated while the optical element 11 is operated. The structure of the silicon hole 20 having the adjusting space 24 formed in the upper opening thereof shows another embodiment of the silicon substrate 15. That is, a function of finding a position where the optical coupling efficiency between the optical element 11 and the optical fiber 22 is maximized is added.

The manufacturing process is the same until the process of forming the metal wiring layer 16 on the silicon substrate 15, and in the silicon hole 20 manufacturing process, the V-groove shape is formed in the silicon hole 20 on the side where the metal wiring layer 16 is located. Anisotropic wet etching is applied to form a conical shape to fabricate a silicon hole 20 in which an optical fiber control space 24 having a form similar to a lever is formed.

5B shows that the optical element 11 is flip-chip bonded and the solder balls 21 are attached, and then the optical fiber 22 is aligned and fixed in the silicon hole 20 in which the adjustment space 24 is formed. It shows that the device package 100 is completed.

In this case, the alignment of the optical fiber 22 inserts the optical fiber 22 into the silicon hole 20. In the case of the optical device 11 having the waveguide 12 by applying a current, the optical device 11 measures light efficiency while emitting light from the optical device 11, or the optical device 11 having the light receiving region 12. ), The optical fiber 22 is lighted to measure the optical efficiency with the optical element 11, and the end of the optical fiber 22 is moved in the X-axis or Y-axis direction in the adjusting space 24 to optimize the optical coupling efficiency. The optical device 22 is fixed to the silicon substrate 15 to find the position to be the optical device package 100.

As described above, the semiconductor optical device package and the method of manufacturing the same according to the present invention have been described with reference to the illustrated drawings. However, the present invention is not limited thereto by the embodiments and drawings disclosed herein, and the scope of the technical spirit of the present invention. Of course, various modifications can be made by those skilled in the art.

The optical device package 100 of the present invention as described above may contribute to the miniaturization of the optical device package by using flip chip bonding and silicon holes, and is a general-purpose optical device that can be simultaneously applied to an optical device having a waveguide or a light receiving area on its surface. Package manufacturing method can be.

In addition, the present invention has the effect of lowering the manufacturing cost by simplifying the process by manual alignment between the optical device and the optical fiber through the self alignment of the flip chip bonding and the silicon hole formed in the silicon substrate.

In addition, the present invention satisfies the electrical characteristics of the package for high-speed optical devices of 10GPbs or more because the heat and heat is transferred through the solder bump in the optical device package structure using flip chip bonding, and the heat radiation characteristics of the silicon substrate The advantage is that the heat dissipation problem can be solved without using a heat dissipation system.

In addition, the present invention can implement a package in a general / standard size that is easy to handle using the silicon substrate even when the size of the optical device is difficult to handle the optical device, and also can provide a method of manufacturing the optical device package, etc. It has all the special features and advantages.

Claims (16)

A solder bump 14 formed on the electrode pad 13 of the optical element 11 having a waveguide or light receiving region 12 and at least one electrode pad 13 on the surface; A metal wiring layer 16 deposited on the upper surface and patterned, a protective film 17 on the metal wiring layer, a flip chip bonding pad 18 formed by selectively patterning the protective film, a substrate metal pad 19 and silicon A silicon substrate 15 having a hole 20; A solder ball (21) on the silicon substrate (15), which is an electrical medium attached to a substrate metal pad (19) formed for electrical connection with an external optical communication system; After aligning the optical element 11 and the optical fiber 22 through the silicon hole 20 formed on the silicon substrate 15, the optical fiber 22 is fixed on the silicon substrate 15 with an adhesive 23 The semiconductor optical device package characterized in that. The method of claim 1, Materials used for the solder bumps 14 and the solder balls 21 include eutectic solder (63Sn / 37Pb), high lead solder (90-97Pb / Sn), and lead-free solder (Lead). free solder: A semiconductor optical device package characterized in that it is manufactured by one selected from Sn / Ag, Sn / Cu, Sn / Zn, Sn / Ag / Cu, Sn / Ag / Bi or Sn / Zn / Bi). The method of claim 1, The material of the silicon substrate 15 is silicon (Silicon) or a compound semiconductor, characterized in that the semiconductor optical device package of any one selected from GaAs, SiGe, InP. The method of claim 1, The metal layer of the metal wiring layer 16 is composed of at least one or more layers, and the metal used may be aluminum or aluminum alloy, titanium or titanium alloy, nickel or nickel alloy, copper or copper alloy, chromium or chromium alloy, or gold. Or a gold alloy selected from any one material. The method of claim 1, As the material of the protective layer 17 layer, a photosensitive or non-photosensitive polyimide (PI), benzocyclobutene (BCB), epoxy resin, silicone resin (Siloxane or Silicone resin) The semiconductor optical device package, characterized in that using any one of silicon nitride. The method of claim 1, The silicon hole (20) is formed on the silicon substrate (15), the semiconductor optical device package, characterized in that by selectively forming an adjustment space (24) in the upper opening of the silicon hole as needed. The method of claim 1, The material of the adhesive 23 for fixing the optical fiber 22 to the silicon hole 20 is characterized by using any one of a photosensitive or non-photosensitive polymer resin adhesive or a ceramic adhesive containing an adhesive component. Semiconductor optical device package. Forming a solder bump (14) on the electrode pad (13) of the optical element (11) having a waveguide or light receiving region (12) on the surface and at least one electrode pad (13); Depositing and patterning a metal thin film on the surface of the silicon substrate 15 to form a metal wiring layer 16; Applying a protective film (17) to the surface of the metal wiring layer formed on the silicon substrate, and selectively patterning the protective film to form a flip chip bonding pad (18) and a substrate metal pad (19); Forming a silicon hole (20) on the silicon substrate (15); Aligning solder bumps (14) formed on the optical device (11) with flip chip bonding pads (18) formed on the silicon substrate (15) to flip-chip bonding the optical devices on the silicon substrate; Attaching a solder ball (21), which is an electrical medium, to the substrate metal pad (19) formed for electrical connection with an external optical communication system on the silicon substrate (15); And After aligning the optical element 11 and the optical fiber 22 through the silicon hole 20 formed on the silicon substrate 15, the optical fiber 22 is fixed on the silicon substrate 15 with an adhesive 23 Method for manufacturing a semiconductor device package comprising the step of manufacturing an optical device package (100). The method of claim 8, Materials used for the solder bumps 14 and the solder balls 21 include eutectic solder (63Sn / 37Pb), high lead solder (90-97Pb / Sn), and lead-free solder (Lead). free solder: A method for manufacturing a semiconductor optical device package, characterized in that it is made of any one selected from Sn / Ag, Sn / Cu, Sn / Zn, Sn / Ag / Cu, Sn / Ag / Bi or Sn / Zn / Bi). The method of claim 8, The silicon substrate 15 is made of silicon or a compound semiconductor, and is made of any one material selected from GaAs, SiGe, and InP. The method of claim 8, The metal layer of the metal wiring layer 16 is composed of at least one or more layers, and the metal used may be aluminum or aluminum alloy, titanium or titanium alloy, nickel or nickel alloy, copper or copper alloy, chromium or chromium alloy, or gold. Or a gold alloy made of any one material. The method of claim 8, The process of applying the protective layer 17 material layer is characterized in that the semiconductor light, characterized in that the coating or deposition by any one method of spin coating (printing) or laminating (Laminating) using a coating equipment Device package manufacturing method. The method of claim 8, The material of the protective layer 17 material layer may be photosensitive or non-photosensitive polyimide (PI), benzocyclobutene (BCB), epoxy resin, silicone resin (Siloxane or Silicone resin). Or silicon nitride. The method of claim 8, The silicon hole 20 on the silicon substrate 15 may be formed by any one of dry etching and wet etching using a photosensitive material as a selective etching mask, or a dry and wet mixed etching method that uses dry and wet. Method for manufacturing a semiconductor optical device package characterized in that. The method of claim 8, In the alignment of the optical element 11 and the optical fiber 22, if necessary, the optical fiber 22 is used by using a silicon hole 20 that optionally includes the adjustment space 24 or does not include the adjustment space 24. Method for manufacturing a semiconductor optical device package, characterized in that the alignment. The method of claim 8, The material of the adhesive 23 for fixing the optical fiber 22 to the silicon hole 20 may be a photosensitive or non-photosensitive polymer resin adhesive, or a ceramic adhesive containing an adhesive component. Method for manufacturing a semiconductor optical device package, characterized in that the fixing.