JP4948436B2 - Laser device frame package and manufacturing method thereof - Google Patents

Description

  The present invention relates to a frame package on which a laser element is mounted and a manufacturing method thereof.

  Laser devices using a semiconductor laser element as a light source are widely used for CDROM, DVD, and optical communication. These laser devices have been provided with various products such as a stem comprising a heat sink and a cap with a window, and a can type. In recent years, since the durability and stability of laser elements have been improved, laser devices that mount laser elements without being hermetically sealed have been widely used.

FIG. 6 shows a conventional manufacturing method of a frame package on which a laser element is mounted. A lead frame 5 shown in FIG. 6A includes a die attach unit 10 on which a laser element is mounted and three leads 12a, 12b, and 12c arranged on one side of the die attach unit 10 as a unit frame unit. .
Of the three leads 12a, 12b, and 12c, the central lead 12b is used as a ground lead and is integrally connected to the die attach unit 10. The lead 12a and the lead 12c are used as signal lines, and are provided with leading ends extending from the rail portion 6a on one side of the lead frame 5 toward the die attach portion 10. The die attach portion 10 around the tip portions of the leads 12a and 12c is cut out in a slit shape so that the leads 12a and 12c and the die attach portion 10 are not electrically short-circuited.

FIG. 6B shows a state in which the lead frame 5 is resin-molded to form a frame package on which a laser element is mounted. The resin molding part 14 provided in the frame package is used when the laser element mounted on the die attach part 10 or the bonding wire connecting the laser element and the leads 12a and 12c is transported by the laser apparatus or when the laser apparatus is mounted. A protruding portion that protrudes outward from the element mounting surface of the die attach portion 10 is provided so as not to contact an external electronic component or the like. The bonding portions 12d of the leads 12a and 12c are exposed from the resin molding portion 14.
JP 2000-357839 A JP 2002-43672 A

  Since the method of forming the frame package on which the laser element is mounted using the lead frame 5 can be manufactured by pressing, it is much easier to manufacture than the method of forming a stem that seals the leads to glass, Mass production is possible, and the manufacturing cost can be effectively reduced. However, the method of forming a frame package using a lead frame has the following problems.

(1) Since the laser element and the lead are connected by wire bonding, the bonding portion of the lead needs to be plated (usually gold plating) to improve the wire bonding property. Since the plating thickness in this case is relatively thick, if plating is performed on the entire lead frame, the plating will also be thickly attached to places where plating is not required, resulting in wasted plating.
(2) The lead frame is resin-molded using a resin mold, but if the product form is different, it is necessary to manufacture the resin mold separately for each product. Get higher. In addition, since a mold is newly manufactured and is in the mass production process, it takes a long time to launch the product.
(3) Since a large number of lead frames are obtained, the quality becomes unstable due to variations in resin molding, resulting in poor product yield. Quality deteriorates due to gas generated during resin molding. For resin molding, a relatively expensive resin having heat resistance is used, but the amount used for the product is about 5 to 10% of the amount of resin used for molding, and the resin is wasted.

  The present invention has been made to solve these problems, and it is possible to easily form a frame package as compared with a method using resin molding without impairing mass productivity and by simplifying the structure of the package. An object of the present invention is to provide a laser device frame package that can be manufactured and a method of manufacturing the same.

In order to achieve the above object, the present invention comprises the following arrangement.
That is, a laser element frame package comprising a die attach part on which a laser element is mounted and a lead connected to the die attach part, wherein the die attach part and the lead are formed by pressing a metal plate. The die attach part is formed as a flat part with an element mounting surface on which a read element is mounted, and a side edge part is formed as a bent part standing on the element mounting surface. An insulating layer having electrical insulating properties is formed on the surface of the bent piece formed by being connected to the inner surface of the bent piece. It is characterized by being supported by pinching.

In addition, the lead formed integrally connected to the die attach portion, and a pair of leads supported by the bent pieces in an arrangement sandwiching the leads, the leads supported by the bent pieces are: It is useful to have a structure in which one lead end is extended and supported on the element mounting surface.
Moreover, the lead is supported more reliably by caulking the portion where the lead is clamped and supported by the bent piece.

  The laser device includes a laser element mounted on the laser element frame package, wherein the laser element is mounted on an element mounting surface of the die attach part, and is electrically insulated from the laser element and the die attach part. Thus, the supported lead is connected by wire bonding.

Also, a method of manufacturing a frame package for a laser element, which is formed by pressing a metal plate formed in a belt shape in order, and supports a die attach portion for mounting the laser element on the metal plate and a lead. A step of forming a bent piece, a step of forming an insulating layer for electrically insulating the die attach portion and the lead on the surface of the bent piece, and setting the lead in accordance with the position where the insulating layer is formed And a step of bending so that the lead is clamped by the bent piece with the insulating layer as the inner surface side.
Further, after forming an insulating layer on the surface of the bent piece, the side edge of the die attach part and the bent piece are bent at right angles to the element mounting surface of the die attach part, and then the insulating layer is formed. The lead is set according to the position.
In addition, in the step of preparing a separate lead frame in which leads are formed in accordance with the positions of the leads and setting the leads in the insulating layer, the lead frame in which the die attach portion and the bent pieces are formed is aligned. Then, the separate lead frame is set. By using a lead frame in which leads are formed, it is easy to align and set the leads to the insulating layer.

  The frame package for a laser device according to the present invention has a simple configuration that can be formed by pressing a metal plate, so that it is easy to manufacture and can easily cope with a wide variety of products. The time required for product launch can be reduced. In addition, according to the method for manufacturing a frame package for a laser element according to the present invention, it is possible to suppress mass variation and easily mass-produce the frame package.

The frame package and the manufacturing method thereof according to the present invention will be described below with reference to the drawings.
FIG. 1 shows a manufacturing process of a frame package on which a laser element is mounted. The frame package manufacturing method of the present embodiment is characterized in that the frame package is formed only by pressing using caulking without using a resin molding method.
A processing die for processing a lead frame is provided with a plurality of processing stages for performing necessary processing while feeding the lead frame in order (fixed dimension feeding) in stages in the lead frame feeding direction. The lead frame is sequentially processed on these processing dies while being sequentially processed on these processing stages to be processed into a predetermined shape.

FIG. 1 shows a state in which a lead frame is processed using a press die corresponding to the processing stages A to F.
The portion A in the figure shows a state in which the die attach portion 10, the pair of bent pieces 16 a and 16 b, and the ground lead 12 b are formed on the lead frame 5.
The die attach part 10 has a rectangular planar shape, and is arranged in the vicinity of the rail part 6b on the other side of the lead frame 5 by a suspension pin 10a.
The lead 12b extends from the rail portion 6a on one side of the lead frame 5 toward the die attach portion 10 and is provided integrally with the die attach portion 10.

The bent pieces 16a and 16b are arranged symmetrically with respect to the lead 12b (in the line direction of the lead 12b) at the base position of the die attach unit 10 (the side to which the lead 12b is connected). Specifically, slits 18a and 18b are formed between the connecting portion to the die attach portion 10 side and the connecting portion to the lead 12b, respectively, and are formed to extend from the die attach portion 10 in a wing shape. .
The die attach portion 10, the bent pieces 16a and 16b, and the lead 12b are usually formed by sequentially performing punching using a plurality of processing stages. Part A in the figure shows a state machined by these machining stages.

The processing stage B is a step of attaching an insulating tape 20 having electrical insulation to the surfaces of the bent pieces 16a and 16b. As the insulating tape 20, for example, a polyimide tape can be used.
In a general manufacturing process of a lead frame on which a semiconductor element is mounted, there is a process of attaching a protective tape to the lead in order to prevent deformation of the inner lead. The same method may be used when the insulating tape 20 is adhered to the bent pieces 16a and 16b. That is, a long insulating tape is arranged above the lead frame 5 so as to intersect with the longitudinal direction of the lead frame 5, the tape is removed from the long insulating tape with a punch, and the punch is pushed down to lead the lead frame 5. The insulating tape 20 is pressed against the bent pieces 16a and 16b.

  In this embodiment, the planar shape of the insulating tape 20 is L so that one end of the insulating tape 20 extends to the die attach portion 10 side so that the leads 12a, 12c and the die attach portion 10 are not electrically short-circuited. It is shaped like a letter. Accordingly, a punch having an L-shaped end surface is used as a punch for pulling out the insulating tape. Since the insulating tape 20 is attached to the bent pieces 16a and 16b, an adhesive tape, such as a B-stage polyimide tape, may be used as the insulating tape 20. Polyimide tape is also effective from the viewpoint of heat resistance.

  The insulating tape 20 is provided as an insulating layer that electrically insulates the leads from the die attach unit 10 and does not necessarily have to be in the form of a tape. For example, it is possible to use a method of coating or printing an insulating material such as a paste having electrical insulating properties, or a chemical treatment such as plating.

The processing stage C is a step of bending the bent pieces 16a and 16b and the side edge portions of the die attach unit 10 into an upright shape.
The bent pieces 16a and 16b and the die attach part 10 are bent at the base position of the slit 18a in the same direction at a right angle to the element mounting surface.
FIG. 2A shows an enlarged view of the bent state of the bent pieces 16a and 16b and the side edges of the die attach unit 10 as viewed from the front side in the processing stage C. FIG. Since the bent pieces 16a and 16b extend outward longer than the side edge portion of the die attach portion 10, the bent pieces 16a and 16b are bent more than the bent portion 10c where the side edge portion of the die attach portion 10 is bent. 16a and 16b extend longer. The insulating tape 20 is attached to the inner surfaces of the bent pieces 16a and 16b of the bent pieces 16a and 16b over substantially the entire area.

  The processing stage D is a process of aligning and setting the leads 12a and 12c on the insulating tape 20. The leads 12a and 12b are set so that their tips are pressed against the insulating tape 20. If a tape having adhesiveness is used for the insulating tape 20, the leads 12a and 12c can be easily set by pressing. When the leads 12a and 12b are set, they are set while being aligned so as to be parallel to the lead 12b.

The leads 12a and 12c are arranged such that one lead end extends beyond the bent pieces 16a and 16b to the element mounting surface of the die attach unit 10. This is because the tips of the leads 12a and 12c become bonding portions 12d for wire bonding. By arranging the leads 12a and 12c so that the tips of the leads 12a and 12c cross the bent pieces 16a and 16b, the leads 12a and 12c are arranged. When the 12c is supported by the bent pieces 16a and 16b, the bonding portion 12d can be exposed.
FIG. 2B shows a state in which the leads 12 a and 12 c are set on the processing stage D. The leads 12a and 12c are set in contact with the insulating tape 20.

In the present embodiment, the leads 12a and 12c formed as a single unit are positioned and set at the bonding position of the insulating tape 20 bonded to the die attach unit 10, but it is troublesome to handle the leads 12a and 12c as a single unit. In this case, as shown in FIG. 3, the leads 12 a and 12 c are set on the die attach unit 10 by using a lead frame 7 in which the leads 12 a and 12 c are formed at positions where the die attach unit 10 is joined. It can also depend on the method.
When the leads 12a and 12c are formed on the lead frame 7, the suspension pins 13 that support the leads 12a and 12c are disposed so as not to interfere with the die attach portion 10 and the bent pieces 16a and 16b. The suspension pin 13 is disposed at a position that does not hinder the processing of bending the 16b.

In the example shown in FIG. 3, when the unit frame portion of the lead frame 5 is sequentially fed to the processing stage D, the lead frame 7 in which only the leads 12 a and 12 c are formed from above is aligned with the lead frame 5 and overlapped. In addition, the leads 12a and 12c are positioned and set on the die attach unit 10. In this case, after the processing stage D, the lead frame 7 is overlapped on the lead frame 5 and processed in order.
It is easy to align the lead frame 7 on which the leads 12a and 12c are formed with the lead frame 5 on which the die attach portion 10 is formed. The suspension pins 13 that support the leads 12a and 12c may be removed from the side edge positions of the leads 12a and 12c when they are no longer needed in a later step.

  As in this embodiment, if the leads 12a and 12c to be wire bonded are formed separately from the die attach unit 10, the leads 12a and 12c are subjected to wire bonding gold plating or the like. The plating is not deposited on the die attach portion 10 or the like as in the prior art, and the waste of plating can be eliminated. Further, there is an advantage that the die attach unit 10 and the like can be easily subjected to dedicated plating different from the wire bonding plating.

In FIG. 1, a processing stage E is a step of sandwiching and bending the bent pieces 16a and 16b so that the leads 12a and 12c are sandwiched inside the crimped bent pieces 16a and 16b, respectively. The figure shows a state in which the leads 12a and 12c are sandwiched and supported by the bent pieces 16a and 16b in the thickness direction.
FIG. 2C corresponds to this step E. The leads 12a and 12b are sandwiched and supported by the bent pieces 16a and 16b. Since the insulating tape 20 is affixed to the inner surface (the inner surface when bending) of the bent pieces 16a and 16b on which the leads 12a and 12c are arranged, the leads 12a and 12c are sandwiched via the insulating tape 20. Thus, electrical short-circuit between the leads 12a and 12c and the die attach unit 10 is avoided.

The processing stage F is a step of caulking the bending positions of the bent pieces 16a and 16b in a state where the leads 12a and 12c are sandwiched between the bent pieces 16a and 16b. The caulking portion 22 has a bent side surface shape by caulking the bent pieces 16a and 16b and the leads 12a and 12c in the thickness direction, and the bent pieces 16a and 16b and the leads 12a and 12c are firmly supported. .
FIG. 2D corresponds to the process F. The configuration in which the leads 12a and 12c are supported by the bent pieces 16a and 16b via the insulating tape 20 is the same as in the previous step. The bent pieces 16a and 16b and the leads 12a and 12c are bent by the caulking process, but the insulating tape 20 is also bent in accordance with these, and the electrical insulating action by the insulating tape 20 is not hindered.
Note that the processing using the lead frame 7 formed with the leads 12a and 12c shown in FIG. 3 is performed in exactly the same processing steps as in the case shown in FIG.

  4A, 4B, and 4C are a side view, a front view, and a bottom view of a single frame package 24 that is separated from the lead frame 5 after the leads 12a and 12c are caulked and fixed. When the lead frame 7 and the lead frame 5 are combined to form a frame package, the frame package 24 is obtained by cutting the suspension pins 13 at the side edge positions of the leads 12a and 12c and removing the suspension pins 13.

As shown in FIG. 4, the frame package 24 includes a die attach unit 10 on which the laser element 28 is mounted and leads 12a, 12b, 12c. The element mounting surface of the die attach unit 10 is formed on a flat surface, and the die attach is performed. Both side edges of the portion 10 are formed as bent portions 10c that are bent at right angles to the element mounting surface. A ground lead 12b is integrally connected to the die attach portion 10, and a pair of signal leads 12a and 12c are sandwiched between the bent pieces 16a and 16b in an arrangement sandwiching the lead 12b, and are caulked and fixed by a caulking portion 22. ing.

The main surface of the die attach unit 10 is formed on a flat surface on which a laser element is mounted, and the bent portions 10c are provided upright on both side edges of the die attach unit 10, thereby reinforcing the strength of the die attach unit 10. In addition, the bent portion 10c serves as a protective portion that protects the laser element 28 and the bonding wire.
Since the leads 12a and 12c are set on the die attach unit 10 via the insulating tape 20 and fixed by caulking, as shown in FIG. 4A, the lead 12b integrally formed with the die attach unit 10 is The position in the side surface direction is shifted by about the thickness of the lead 12b.

The electrical insulation between the leads 12a and 12c and the die attach part 10 is based on the caulking and fixing of the leads 12a and 12c via an insulating tape 20 having electrical insulation.
The leads 12a and 12c are arranged such that one lead end on the die attach part 10 side extends beyond the bent pieces 16a and 16b to the die attach part 10 side, so that the bonding part 12d becomes the die attach part. It is exposed as a plane parallel to 10 element mounting surfaces. The insulating tape 20 is also interposed between the tips of the leads 12a and 12c and the die attach part 10, so that an electrical short circuit between the leads 12a and 12c and the die attach part 10 is avoided.

Since the manufacturing method of the frame package 24 of this embodiment assembles the frame package 24 only by press work, productivity can be greatly improved compared with the method of using the conventional resin molding method. In addition, it is possible to suppress variations in product quality as compared with the case of using a resin molding method, and it is possible to stabilize the quality.
In addition, since it is not necessary to manufacture a mold for resin molding, it is possible to reduce the manufacturing cost of the mold and reduce the time required for starting up a new product.

FIG. 5 shows a laser device 30 in which the laser element 28 is mounted on the frame package 24. The laser element 28 is mounted on the element mounting surface of the die attach unit 10, and the laser element 28 and the bonding parts 12 d of the leads 12 a and 12 c are wire-bonded by bonding wires 29. Bent portions 10c provided on both side edges to standing shape of the die attach portion 10 acts to protect the reinforcement of the die attach portion 10, and the laser element 28 and the bonding wire 29. Laser light is emitted upward from the laser element 28 in parallel with the element mounting surface of the die attach unit 10.
Since the laser device 30 of the present embodiment has a simple configuration formed only by pressing, it is easy to manufacture and can effectively reduce the manufacturing cost.

In the above-described embodiment, the frame package including three leads has been described. However, the form of the frame package, such as the number of leads and the shape of the die attach portion, is not limited to the configuration of the above-described embodiment. . Moreover, although the bending part 10c was provided in the both-sides edge part of the die attach part 10 in the said embodiment, it is also possible to provide a bending part in the upper side part of the die attach part 10 to which a laser beam is radiated | emitted. When a bent portion is provided on the upper side, an opening or a cutout may be provided in the bent portion so as not to shield the laser beam.
Moreover, the material which comprises a frame package can also select suitably materials, such as an iron-nickel alloy and copper.

It is explanatory drawing which shows the manufacturing process of the frame package which concerns on this invention. It is explanatory drawing which shows the bending process in process C-F. It is explanatory drawing which shows the other manufacturing process of a frame package. They are a side view (a), a front view (b), and a bottom view (c) of the frame package. It is a front view of a laser apparatus. It is explanatory drawing which shows the manufacturing process of the conventional frame package.

Explanation of symbols

5, 7 Lead frame 10 Die attach part 10c Bending part 12a, 12b, 12c Lead 12d Bonding part 13 Hanging pin 14 Resin molding part 16a, 16b, Bending piece 20 Insulating tape 22 Caulking part 24 Frame package 28 Laser element 29 Bonding wire 30 Laser equipment

Claims (7)

A frame package for a laser element comprising a die attach part on which a laser element is mounted and a lead provided connected to the die attach part,
The die attach part and the lead are formed by pressing a metal plate,
The die attach part is formed as a bent part where the element mounting surface on which the laser element is mounted is formed as a flat surface, and the side edge part stands up with respect to the element mounting surface,
An insulating layer having electrical insulation is formed on the surface of the bent piece formed connected to the die attach portion, and the bent portion is electrically insulated from the die attach portion with the insulating layer as an inner surface side. A frame package for a laser device, wherein a lead is supported by being clamped by a piece. A lead formed integrally connected to the die attach part;
And a pair of leads supported by the bent pieces, and the leads supported by the bent pieces are supported by extending one lead end on the element mounting surface. The frame package for a laser device according to claim 1, wherein the frame package is for a laser device.   3. The laser device frame package according to claim 1, wherein a crimping process is applied to a portion where the lead is clamped and supported by the bent piece. A laser device comprising a laser element mounted on the laser element frame package according to any one of claims 1 to 3,
A laser element is mounted on the element mounting surface of the die attach unit,
A laser device characterized in that the laser element and a lead electrically insulated and supported by the die attach part are connected by wire bonding. A method of manufacturing a frame package for a laser element, which is formed by performing press processing while sequentially feeding a metal plate formed in a strip shape,
A step of forming a die attach part for mounting a laser element on the metal plate, and a bent piece for supporting a lead;
Forming an insulating layer on the surface of the bent piece to electrically insulate the die attach part and the lead;
Setting a lead in accordance with the position where the insulating layer is formed;
And a step of bending the insulating layer as an inner surface side so that the leads are clamped by the bent piece. After forming an insulating layer on the surface of the bent piece,
The side edge of the die attach part and the bent piece are bent at right angles to the element mounting surface of the die attach part,
6. The method of manufacturing a frame package for a laser element according to claim 5, wherein a lead is set in accordance with a position where the insulating layer is formed. Prepare a separate lead frame in which the lead is formed according to the arrangement position of the lead,
7. The step of setting a lead on the insulating layer, wherein the separate lead frame is set in alignment with the lead frame on which the die attach portion and the bent piece are formed. A method for manufacturing a frame package for a laser device.