JPH0592264A - Welding device and welding method - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a welding apparatus and a welding method capable of shortening the tact time (the time from attaching the stem to the stem holder and removing it) and improving the productivity. [Structure] A disk-shaped turntable 13 and a plurality of stem holders 1, ..., 6 which are radially attached to the periphery of the turntable 13 at predetermined angles and each of which holds a stem 15 toward the outside of the turntable 13. Equipped with. Further, a plurality of heat baths 8, ..., 12 are provided around the turntable 13 in a radial pattern at each of the above angles, each of which is capable of maintaining a predetermined temperature. The stem 15 on which the component 17 to be bonded to the bonding agent is placed is held by the stem holders 1, ..., 6 toward the outside of the rotary table. Rotating the rotary table 13 at each of the above angles while maintaining high temperature, proper temperature, and low temperature in the respective heating baths 8, ...
The stem 15 is brought into contact with each of the hot baths 8, ..., 12 in sequence to melt and solidify the bonding agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding apparatus and a welding method, and more particularly to a welding apparatus and a welding method for welding a component such as a semiconductor chip to a stem by using a bonding agent.

[0002]

2. Description of the Related Art In general, a component whose performance is affected by temperature is joined to a stem (radiating base member) by using a joining agent containing metal to radiate heat. For example, in the case of a semiconductor laser chip, as shown in FIGS. 4 (a) and 4 (b), first, the stem 105 is held on the stem holder 101 by the stem chucking plate 102 (the entire structure of the welding device is shown in FIG. 3). Shown). Stem 105 header 1
Indium 106 is previously attached to 05a as a bonding agent. Then, the semiconductor laser chip 107 is placed on the indium 106, and the stem 105 is brought into pressure contact with the ceramic heater 104. In this state, the temperature of the ceramic heater 104 is controlled so that the indium 10
6 is melted and the semiconductor laser chip 10 is attached to the stem 105.
Join 7 Conventionally, as shown in FIG. 5, the temperature control of the ceramic heater 104 includes a rising time until the actual heating temperature is raised to an appropriate temperature and an appropriate heating time for keeping the heating temperature at an appropriate temperature (within an appropriate temperature range). And a cooling time in which the heating temperature is forcibly lowered by air blowing and a standing time in which the heating temperature is naturally left until the temperature reaches room temperature.

[0003]

However, in the above-mentioned conventional welding method, the stem holder 101 is provided with the stem 105.
There is a problem that productivity is not good because the time from installation to removal is long (hereinafter referred to as "tact time"). Because the ceramic heater 104 has a large heat capacity, rapid heating and rapid cooling cannot be performed. In particular, rapid heating (increasing the temperature rise rate during the rise time) is regulated to keep the overshoot (difference between the actual heating temperature and the appropriate temperature) immediately after entering the appropriate heating time within the appropriate temperature range. To be done.

Therefore, an object of the present invention is to provide a welding apparatus and a welding method which can shorten the takt time and improve the productivity.

[0005]

In order to achieve the above object, a welding apparatus of the present invention is a disk-shaped rotary table, and a plurality of radial tables are attached to a peripheral portion of the rotary table at predetermined angles. The present invention is characterized by comprising a stem holder capable of holding the stem toward the outside of the rotary table, and a plurality of heat baths radially provided around the rotary table at each of the above angles and capable of maintaining a predetermined temperature.

Further, it is desirable to provide a stem mounting portion for mounting the stem on the stem holder at one position where the heat bath should be provided around the rotary table.

Further, it is desirable that the temperature of each heat bath is set to a high temperature, an appropriate temperature, and a low temperature in order from the side closer to the stem mounting portion.

Further, it is preferable that each of the heat baths has a ceramic heater that can move in a radial direction with respect to the rotary table and is brought into pressure contact with a stem attached to the stem holder.

In the welding method of the present invention, a disk-shaped rotary table, a plurality of stem holders radially attached to the peripheral portion of the rotary table at a predetermined angle, and at the above-mentioned angle around the rotary table. Using a plurality of heat baths radially provided in
A welding method of welding a predetermined component to a stem via a bonding agent, wherein the stem holder holds a stem on which a component to be bonded to the bonding agent is placed in advance toward the outside of the rotary table. , High temperature, appropriate temperature,
It is characterized by having a step of rotating the rotary table at each of the angles while maintaining a low temperature, sequentially contacting the stems with the heat baths, and melting and solidifying the bonding agent on the stems. ..

[0010]

The welding apparatus of the present invention is driven as follows.
First, the stem holder is made to hold the stem on which parts to be joined with the joining agent are placed in advance toward the outside of the rotary table. In addition, each of the heat baths around the rotary table is maintained at a high temperature, an appropriate temperature, and a low temperature, for example. In this state, the rotary table is rotated at each of the above angles, and the stem is brought into contact with each of the heat baths in sequence. Thereby, the bonding agent on the stem is rapidly heated and melted in the high-temperature heat bath (rapid heating unit), and after the required time has elapsed in the proper-temperature heat bath (suitable-temperature heating unit), It is rapidly cooled and solidified in a low temperature heat bath (cooling part) (however, the cooling rate is within the range where crystal strain during solidification does not matter). After this, the stem is removed from the stem holder. As described above, since this welding device is provided with the plurality of heat baths, the respective heat baths can be set to different temperatures in advance. Therefore, it is not necessary to provide time for raising and lowering the temperature of the heating bath during the joining process, and as a result, the takt time is shortened as compared with the conventional case. Moreover, since a plurality of stem holders are provided, for example, when one stem (and stem holder) moves from the rapid heating section to the proper temperature heating section, the next stem holder is moved to the rapid heating section, and the one stem The joining of the next stem can be started while joining is taking place. That is, the bonding work can be sequentially advanced in parallel by the number of heat baths. Therefore, the takt time is significantly shortened and the productivity is improved. Moreover, since it is only necessary to maintain a constant temperature in each heat bath, temperature control can be easily performed. It is expected that the heating temperature will momentarily drop when the stem holder moves between the heating baths, but it can be suppressed to a level (within an appropriate temperature range) that does not pose any problem in practice.

When a stem mounting portion for mounting the stem on the stem holder is provided at one position where the heat bath is to be provided around the rotary table, the rotary table is rotated and the stem holder is mounted on the stem mounting section. The stem can be mounted when the position is reached. That is, the work of mounting the stem and the heating / cooling work in each heat bath can be synchronized with the rotation cycle of the turntable. Therefore, the productivity is further improved.

In addition, each of the heat baths can move in a radial direction with respect to the rotary table, and when the stem has a ceramic heater which is brought into pressure contact with a stem attached to the stem holder, the rotary table is rotated so that the stem holder receives each heat. Upon reaching the bath position, the stem rapidly reaches the temperature of this ceramic heater. Therefore, the tact time is shortened. Moreover, since the temperature of the ceramic heater can be set with a constant current, the temperature control is easily performed.

[0013]

EXAMPLES The welding apparatus and welding method of the present invention will be described in detail below with reference to examples.

FIG. 1 shows a welding apparatus according to an embodiment of the present invention as viewed from above. This welding device includes a disk-shaped rotary table 13 and six stem holders 1, 2, which are radially mounted around the rotary table 13 every 60 degrees.
It is equipped with 3, 4, 5, and 6. Each stem holder 1, ..., 6
Consists of a main body 21 and a stem chucking plate 22,
Each of the stems can be held toward the outside of the turntable 13. Five heat baths 8, 9, 10, 11, 12 are provided around the rotary table 13 at intervals of 60 degrees, and a stem mounting arm (stem mounting portion) 7 is provided at the remaining one position. ing. The stem mounting arm 7 can move to the position 7a shown by the broken line when the stem holders 1, ..., 6 come to the close position, and the stem 15 can be mounted on the stem holders 1 ,. Each of the heating baths 8, ..., 12 is composed of a ceramic heater 23 and a heater holder 24 holding the ceramic heater 23, and a predetermined temperature can be maintained by supplying a constant current to each of the ceramic heaters 23. Actually, the heat bath (rapid heating part) 8 is set to a high temperature, the heat baths (appropriate temperature heating part) 9 and 10 are set to an appropriate temperature, and the heat bath (cooling part) 11 is set to a low temperature in order from the side close to the stem mounting arm 7. ing. 12 is a preliminary heat bath. Each of the above heat baths 8, ..., 12 is a turntable 1
It is possible to move radially with respect to 3. As a result, when the rotary table 13 is rotated and the stem holders 1, ..., 6 come to the close position, the ceramic heater 23 is brought into pressure contact with the stems 17 attached to the respective stem holders. Then, when the rotary table 13 is about to rotate next time, the rotary table 13 is separated.

This welding device is driven as follows. First, the stem holder 1 is made to hold the stem 15 on which a component (for example, a semiconductor laser chip) 17 to be bonded with a bonding agent in advance is mounted. In this state, the rotary table 13 is rotated clockwise by 60 degrees to bring the stem 15 into contact with the ceramic heater 23 of the rapid heating section 8. As a result, the bonding agent on the stem 15 is rapidly heated and melted. As shown in FIG. 2, the actual heating temperature (indicated by the solid line A in the figure)
When the temperature reaches the appropriate temperature T1, the ceramic heater 23 is separated from the stem 15. In the figure, T is the moving time and CT is the cycle time. The broken line B indicates the conventional heating temperature shown in FIG. Subsequently, the rotary table 13 shown in FIG. 1 is rotated by 60 degrees to bring the ceramic heater 23 of the appropriate temperature heating section 9 into contact with the stem 15 and maintain the appropriate temperature. After the predetermined time T2 has elapsed in the appropriate temperature heating unit 9, the appropriate temperature heating unit 10 also holds the stem 15 at the appropriate temperature for the time T3. Then, the rotary table 13 is rotated by 60 degrees, and the stem 15 is rotated by the cooling unit 11.
The ceramic heater 23 is brought into contact with. As a result, the stem 15 is rapidly cooled, and the above-mentioned bonding agent is solidified (however, the cooling rate is within a range where crystal strain during solidification does not matter). Then, the stem 15 is removed from the stem holder 1.

As described above, since this welding apparatus is provided with the plurality of heat baths 8, ..., 12, the heat baths 8, ..., 12 can be set to different temperatures in advance. Therefore, it is not necessary to provide the time for raising and lowering the temperature of the hot baths 8, ..., 12 during the cycle time, and as a result, the tact time can be shortened as compared with the conventional case. Moreover, since a plurality of stem holders 1, ..., 6 are provided, for example, when one stem 15 and the stem holder 1 are moved from the rapid heating section 8 to the proper temperature heating section 9, the next stem holder is transferred to the rapid heating section 8. It is possible to move and start the joining of the next stem while the joining of the one stem 15 is being performed. That is, the bonding work can be sequentially advanced in parallel by the number of heat baths. Therefore, the solid line A and the broken line B in FIG.
As shown as a difference from the above, the takt time can be significantly shortened and the productivity can be improved. Moreover, since each of the heating baths 8, ..., 12 only needs to maintain a constant temperature, the temperature can be easily controlled. It is expected that the temperature of the stem will momentarily drop during the time T during which the stem holder moves between the heat baths, but it can be suppressed to a level (within an appropriate temperature range) that does not pose any problem in practice.

Further, since the stem mounting arm 7 is provided at a position where the heat bath should be provided around the rotary table 13, the stem can be mounted when the rotary table 13 is rotated and the stem holder comes to the close position. it can. That is, the work of mounting the stem and the heating and cooling work in each heat bath,
It can be synchronized with the rotation cycle of the turntable 13. Therefore, productivity can be improved.

[0018]

As is apparent from the above, the welding apparatus of the present invention is provided with a disk-shaped rotary base and a plurality of radial mounts on the periphery of the rotary base at predetermined angles. Stem holder that can be held toward the outside of
A plurality of radial baths are provided around the rotary table at each of the above angles, and each has a heat bath that can maintain a predetermined temperature. There is no need to spend time to raise or lower the bath temperature. Moreover, it is possible to carry out the bonding work sequentially in parallel by the number of heat baths. Therefore, the takt time can be significantly reduced and the productivity can be improved.

Further, when a stem mounting portion for mounting the stem on the stem holder is provided at one position where the heat bath is to be provided around the rotary table, work for mounting the stem and heating in each heat bath, The cooling work can be synchronized with the rotation cycle of the turntable, and the productivity can be improved.

In addition, each of the heat baths can move in a radial direction with respect to the rotary table, and has a ceramic heater that is brought into pressure contact with the stem mounted to the stem holder, the stem can be rapidly heated or cooled. Therefore, the tact time can be shortened. Moreover, since the temperature of the ceramic heater can be set at a constant current, the temperature can be easily controlled.

In the welding method of the present invention, a disk-shaped turntable, a plurality of stem holders radially attached to the periphery of the turntable at predetermined angles, and at the above-mentioned angles around the turntable. Using a plurality of heat baths radially provided in
A welding method of welding a predetermined component to a stem via a bonding agent, wherein the stem holder holds a stem on which a component to be bonded to the bonding agent is placed in advance toward the outside of the rotary table. , High temperature, appropriate temperature,
By rotating the rotary table at each angle while maintaining the low temperature, the step of sequentially contacting the stem with each of the heat baths to melt and solidify the bonding agent on the stem, The tact time can be greatly reduced, and productivity can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a welding apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing the progress of heating temperature when a component is mounted on the stem using the welding device.

FIG. 3 is a diagram showing an overall configuration of a conventional welding device.

FIG. 4 is a view showing a main part of the conventional welding device.

FIG. 5 is a diagram showing the progress of heating temperature when a component is mounted on the stem using the conventional welding device.

[Explanation of symbols]

 1,2,3,4,5,6 Stem holder 7 Stem mounting arm 8,9,10,11,12 Heat bath 15 Stem 17 Parts 21 Stem holder body 22 Stem chucking plate 23 Ceramic heater 24 Heater holder

Claims (5)

[Claims] 1. A disk-shaped turntable, a plurality of stem holders radially attached to the periphery of the turntable at predetermined angles, each of which holds a stem toward the outside of the turntable. A welding apparatus, characterized in that a plurality of radial baths are provided around the circumference at each of the above angles and each has a heat bath capable of maintaining a predetermined temperature. 2. A stem mounting portion for mounting a stem on the stem holder is provided at one position where the heat bath is to be provided around the rotary table.
Welding device according to. 3. The welding device according to claim 2, wherein the temperature of each heat bath is set to a high temperature, an appropriate temperature, and a low temperature in order from the side closer to the stem mounting portion. 4. Each of the heat baths has a ceramic heater which is movable in a radial direction with respect to the rotary table and is in pressure contact with a stem attached to the stem holder. The welding apparatus according to any one of 1. 5. A disk-shaped turntable, a plurality of stem holders radially mounted at a predetermined angle around the turntable, and a plurality of radial holders around the turntable at each angle. A welding method for welding a predetermined component to a stem via a bonding agent using a heat bath, wherein the stem holder, on which the component to be bonded with the bonding agent is placed in advance, is placed outside the rotary table. And a step of holding it toward each of the heat baths, sequentially rotating the rotary table at each of the above angles while maintaining a high temperature, an appropriate temperature, and a low temperature, and sequentially bringing the stems into contact with the heat baths. A welding method comprising the steps of melting and solidifying a bonding agent on a stem.