JP2000183200A - Package for housing optical semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a package for housing an optical semiconductor element which converts optical signal to electric signal and transmits it accurately to a specified external electric circuit, by realizing fast conversion speed of an optical signal to an electric signal in an optical semiconductor element. SOLUTION: The package for housing an optical semiconductor element consists of a substrate 1 with a recessed part 1a for storing an optical semiconductor element 3 in an upper surface, a through hole 1b which is formed in a side part of the substrate 1 and communicates the recessed part 1a to the outside, a plurality of wiring layers 4 which are formed from an inner surface of the recessed part 1a to an outside surface of the substrate 1 and whereto an electrode of the optical semiconductor element 3 is connected, a plurality of external lead terminals fixed to the wiring layer 4 formed in an outside surface of the substrate 1, and a lid body 3 which is fixed to an upper surface of the substrate 1 and closes the recessed part 1a. A groove part is formed between the wiring layers 4 on an outside surface of the substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor element housing package for housing an optical semiconductor element.

[0002]

2. Description of the Related Art Conventionally, an optical semiconductor element housing package for housing an optical semiconductor element is generally made of an aluminum oxide sintered body and has a concave portion on its upper surface for housing the optical semiconductor element, Formed on the side of the substrate,
The recess is communicated to the outside, and a through hole through which an optical fiber for transmitting an optical signal to the optical semiconductor element housed in the recess is inserted, and a hole is formed from the inner surface of the recess to the side surface of the base, and the electrode of the optical semiconductor element is connected. A plurality of wiring layers made of a high melting point metal powder such as tungsten, molybdenum, manganese, etc., and a plurality of metal layers made of a metal material such as an iron-nickel-cobalt alloy attached to the wiring layer formed on the side surface of the base. And an external lead terminal, and a lid attached to the upper surface of the base and closing the recess. The optical semiconductor element is provided with an adhesive such as glass, resin, or brazing material in the recess of the base. Each electrode of the optical semiconductor element is electrically connected to a wiring layer via a bonding wire, and then a lid is formed on the upper surface of the base by glass,
The optical semiconductor element is hermetically housed inside a container consisting of a base and a lid, and an optical fiber is inserted and fixed in a through-hole of the base. It becomes an optical semiconductor device.

Such an optical semiconductor device irradiates an optical semiconductor element with an optical signal transmitted from an optical fiber, causes the optical semiconductor element to transmit and receive the optical signal, and converts the optical signal into an electric signal. It is used for high-speed communication and the like by transmitting a signal to an external electric circuit via a wiring layer and an external lead terminal.

[0004]

However, in this conventional package for housing an optical semiconductor element, a large number of wiring layers are provided side by side on a side surface of the substrate with an aluminum oxide sintered body forming a substrate therebetween. That the relative permittivity of the aluminum oxide sintered body is about 10 (1 MH at room temperature).
z), there is a disadvantage that a large capacitance is formed between adjacent wiring layers, and the conversion of an optical signal into an electric signal in the optical semiconductor element becomes slow due to the large capacitance. Was. Particularly in optical communication, the optical signal transmitted from the optical fiber to the optical semiconductor device is extremely high speed. Cannot be transmitted to the optical communication, which is a fatal drawback for optical communication.

The present invention has been made in view of the above-mentioned drawbacks, and has as its object to increase the speed of converting an optical signal into an electrical signal in an optical semiconductor device, and to convert an optical signal into an electrical signal to provide a predetermined external electrical circuit. It is an object of the present invention to provide an optical semiconductor element housing package that can accurately transmit an optical semiconductor device.

[0006]

According to the present invention, there is provided a base having a concave portion for accommodating an optical semiconductor element on an upper surface, a through-hole formed on a side portion of the base and communicating the concave portion to the outside, and the concave portion. A plurality of wiring layers formed from the inner surface to the outer surface of the base and connected to the electrodes of the optical semiconductor element, and a plurality of external lead terminals attached to the wiring layers formed on the outer surface of the base And a cover attached to the upper surface of the base and closing the recess, wherein a groove is formed between wiring layers on the outer surface of the base. Things.

According to the package for housing an optical semiconductor element of the present invention, since the groove is formed between the wiring layers on the outer surface of the substrate provided with the plurality of wiring layers, the capacitance between the adjacent wiring layers is reduced. As a result, the speed of converting an optical signal to an electrical signal in the optical semiconductor device is also high, and the optical signal transmitted via the optical fiber can be reliably converted to an electrical signal by the optical semiconductor device. And the converted electric signal can be accurately transmitted to a predetermined external electric circuit.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the accompanying drawings. 1 to 3 show an embodiment of the package for housing an optical semiconductor element according to the present invention, wherein 1 is a base, and 2 is a lid. The base 1 and the lid 2 constitute a container for housing the optical semiconductor element 3 therein.

The base 1 is provided on its upper surface with a recess 1a forming a space for accommodating the optical semiconductor element 3,
The optical semiconductor element 3 is mounted and fixed on the bottom surface of the concave portion 1a.

The base 1 is made of an aluminum oxide-based sintered body. For example, a raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide is mixed with a suitable organic binder, a solvent, and the like to form a slurry. At the same time, the slurry is formed into a ceramic green sheet (ceramic green sheet) by employing a doctor blade method or a calender roll method. Thereafter, the ceramic green sheet is subjected to an appropriate punching process and a plurality of the green sheets are laminated. , At about 1600 ° C.

A plurality of wiring layers 4 are formed on the substrate 1 from the inner surface of the concave portion 1a to the outer surface of the substrate 1, and a region of the wiring layer 4 exposed in the concave portion 1a has an optical semiconductor element. 3 are electrically connected to each other through bonding wires 5, and external lead terminals 6 connected to an external electric circuit are made of a brazing material such as silver brazing in a region formed on the outer surface of the base 1. It is attached via brazing.

The wiring layer 4 functions as a conductive path for connecting each electrode of the optical semiconductor element 3 to an external electric circuit, and is formed of a high melting point metal powder such as tungsten, molybdenum, and manganese.

The wiring layer 4 is formed by adding a metal paste obtained by adding a suitable organic binder, a solvent and the like to a high melting point metal powder such as tungsten, molybdenum, manganese or the like on a ceramic green sheet serving as the substrate 1 in advance by using a conventionally known screen. By printing and applying a predetermined pattern by a printing method, the adhesive is formed from the inside of the concave portion 1a of the base 1 to the outer surface of the base 1.

The wiring layer 4 is preferably provided with a metal having excellent corrosion resistance such as nickel and gold and excellent wettability with a brazing material to a thickness of 1 μm to 20 μm by a plating method on the exposed surface. In addition, the oxidation corrosion of the wiring layer 4 can be effectively prevented, and the brazing of the external lead terminals 6 to the wiring layer 4 can be firmly performed. Therefore, the wiring layer 4 is made of a metal having excellent corrosion resistance such as nickel and gold and having excellent wettability with a brazing material of 1 μm on the exposed surface.
Preferably, it is applied to a thickness of from 20 to 20 μm.

Further, an external lead terminal 6 is attached to the wiring layer 4 by brazing via a brazing material such as silver brazing, and the external lead terminal 6 is connected to the optical semiconductor element 3 contained in the container.
The optical semiconductor element 3 accommodated in the container by connecting the external lead terminals 6 to the external electric circuit is electrically connected to the external electric circuit.
And the external lead terminal 6 is connected to an external electric circuit.

The external lead terminal 6 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy.
For example, an ingot made of a metal material such as an iron-nickel-cobalt alloy is formed into a predetermined shape by applying a conventionally known metal working method such as a rolling method or a punching method.

The external lead terminal 6 is formed by coating a metal having excellent corrosion resistance such as nickel and gold and having excellent wettability with a brazing material to a thickness of 1 μm to 20 μm on an exposed surface by plating. By doing so, the oxidative corrosion of the external lead terminal 6 can be effectively prevented, and when the external lead terminal 6 is connected to an external electric circuit, the connection can be reliably and firmly made. Therefore, it is preferable that the external lead terminal 6 is coated with a metal having excellent corrosion resistance such as nickel and gold and excellent wettability with a brazing material to a thickness of 1 μm to 20 μm on the exposed surface.

The base 1 to which the external lead terminals 6 are attached
Also, a through-hole 1b is formed on the side portion thereof.

The through hole 1b is formed in a concave portion 1a provided in the base 1.
The optical fiber 7 is inserted into the through hole 1b, and functions as an insertion hole for inserting the optical fiber 7 from the outside to the inside of the container.

The through hole 1b is formed in the ceramic green sheet serving as the base body 1 by forming a hole in advance by a punching method, or by forming a hole in a side portion of the base body 1. It is formed in a predetermined shape on the side.

For example, a frame-like base member 8 is brazed around the through hole 1b on the outer surface of the base 1, and a metal flange attached to the optical fiber 7 is attached to the base member 8. 9 is welded using a laser beam such as YAG.

The base member 8 includes the optical fiber 7 and the base 1.
Acts as a base metal material when attaching to steel. For example, it is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy. It is formed into a predetermined shape by applying a conventionally known metal working method such as a working method.

The base member 8 has a metal layer made of a high melting point metal powder such as tungsten, molybdenum, manganese or the like previously applied to the outer surface of the base 1 around the through hole 1b. Is attached to the outer surface of the base 1 around the through hole 1b by brazing.

A metal flange 9 attached to the optical fiber 7 is welded to the base member 8 by using a laser beam such as YAG, so that the optical fiber 7 for transmitting an optical signal to the optical semiconductor element 3 is provided on the base member. It will be fixed to 1.

Further, a groove 10 is formed between the wiring layers 4 on the outer surface of the base 1. In the groove 10, an aluminum oxide sintered body forming the base 1 having a relative dielectric constant of as high as about 10 (room temperature 1 MHz) is interposed between the adjacent wiring layers 4,
A groove 10 is formed between the adjacent wiring layers 4 on the outer surface of the base 1 so as to prevent an increase in the capacitance between the adjacent wiring layers 4. By removing the sintered body, the capacitance between the wiring layers 4 is reduced, and as a result, the speed of converting an optical signal into an electrical signal in the optical semiconductor element 3 is increased, and the transmission speed is increased via the optical fiber 7. The converted optical signal can be reliably converted into an electric signal by the optical semiconductor element 3, and the converted electric signal can be accurately transmitted to a predetermined external electric circuit.

The groove 10 is formed on the outer surface of the base 1 by forming a predetermined hole in the ceramic green sheet serving as the base 1 in advance by a punching method or by grinding the side of the base 1. It is formed between adjacent wiring layers 4.

It is preferable that the width of the groove 10 is set to be equal to the entire width between the adjacent wiring layers 4, and that if the depth is set to 0.1 mm or more, the capacitance between the adjacent wiring layers 4 is extremely small. Can be made. Therefore, the width of the groove 10 is set to the entire width between the adjacent wiring layers 4,
Preferably, the depth is set to 0.1 mm or more.

On the other hand, a lid 2 made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy is joined to the upper surface of the base 1, thereby forming the base 1 and the lid 2. The optical semiconductor element 3 is hermetically sealed inside the container.

The lid 2 is formed into a predetermined shape by subjecting an ingot (lumps) of, for example, an iron-nickel-cobalt alloy to a conventionally known metal working method such as a rolling method or a punching method. .

Thus, according to the package for housing an optical semiconductor element of the present invention, the optical semiconductor element 3 is mounted and fixed on the bottom surface of the concave portion 1 a of the base 1, and each electrode of the optical semiconductor element 3 is externally connected via the bonding wire 5. The lead terminal 6 is electrically connected to the soldered wiring layer 4 and then the base 1
The lid 2 is bonded to the upper surface of the substrate 1, the optical semiconductor element 3 is accommodated in a container formed of the base 1 and the lid 2, and finally the optical fiber 7 is attached to the through hole 1 b formed in the base 1. It becomes an optical semiconductor device as a product.

The optical semiconductor device transmits an optical signal from the outside to the optical semiconductor element 3 via the optical fiber 7, converts the optical signal into an electric signal in the optical semiconductor element 3, and converts the converted electric signal into the wiring layer 4 and It is used for optical communication or the like by transmitting it to an external electric circuit via the external lead terminal 6.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

[0033]

According to the package for housing an optical semiconductor element of the present invention, since a groove is formed between the wiring layers on the outer surface of the substrate on which a plurality of wiring layers are juxtaposed, the static electricity between the adjacent wiring layers is reduced. The capacity becomes a small value, and as a result, the conversion speed of the optical signal to the electric signal in the optical semiconductor device is also high, and the optical signal transmitted via the optical fiber is reliably converted to the electric signal by the optical semiconductor device. And the converted electric signal can be accurately transmitted to a predetermined external electric circuit.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a package for housing an optical semiconductor element of the present invention.

FIG. 2 is a side view of the semiconductor element housing package shown in FIG. 1;

FIG. 3 is a plan view of the semiconductor device housing package shown in FIG. 1 with a lid removed.

[Explanation of symbols]

 1 base 1a recess 1b through-hole 2 lid 3 light Semiconductor element 4 Wiring layer 6 External lead terminal 7 Optical fiber 10 Groove

Claims (1)

[Claims] 1. A base having a concave portion for accommodating an optical semiconductor element on an upper surface, a through hole formed in a side portion of the base and communicating the concave portion to the outside, and formed from an inner surface of the concave portion to an outer surface of the substrate. A plurality of wiring layers to which electrodes of the optical semiconductor element are connected; a plurality of external lead terminals attached to a wiring layer formed on an outer surface of the base; An optical semiconductor element housing package comprising: a lid attached to the housing to cover the recess, wherein a groove is formed between wiring layers on an outer surface of the base.