JPH077029A - Manufacture of semiconductor device and semiconductor manufacturing device using it - Google Patents

Abstract

PURPOSE:To reduce treatment time for manufacturing semiconductor device including heat treatment and to miniaturize the device. CONSTITUTION:A magazine 21 which can be replaced easily by an elevator 26 is moved into and laid out in a box oven 13 for performing heat treatment. Then, a lead frame 12 to be transported is housed by raising and lowering the magazine 21 to a specific position, is heat-treated for a specific amount of time, and then is unloaded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device including heat treatment in semiconductor manufacturing.

In recent years, in semiconductor manufacturing, simplification of processes and shortening of processing time have been demanded. For example, when heat treatment is performed, it is required that variation in temperature distribution is small, waiting time and processing time are short. To be done.

[0003]

2. Description of the Related Art Conventionally, in a semiconductor manufacturing process, there is a process of mounting a semiconductor chip on a die stage of a lead frame, for example. This process is called die attachment, and in the die attachment, an adhesive agent of silver paste in which silver and a resin solvent are mixed is generally used.

The silver paste is excellent in workability and mass productivity, and the silver paste is applied by printing or transfer and the semiconductor chip is placed on the stage of the lead frame and heat-bonded.

Adhesion is performed by heating in a constant temperature oven, and is performed by degassing the solvent in the silver paste and curing it.
This process is called cure, and the constant temperature oven used is called cure oven.

In the curing furnace, a plurality of lead frames on which semiconductor chips are mounted are housed in a magazine, and a large number of magazines are put in a large furnace at one time for heating.

On the other hand, there is also a method in which the cure is carried out for each lead frame, instead of storing a plurality of lead frames in a magazine. In this method, a semiconductor chip is placed on a stage of a lead frame using a quick-drying silver paste, and then hot air is directly blown to dry the semiconductor chip.

[0008]

However, performing the curing in magazine units increases the size of the furnace and requires a certain number of magazines, which increases the waiting time, while shortening the waiting time. However, there is a problem in that when the magazines of different types are collectively processed in the furnace, they may be confused when the magazines are returned in the next process.

Further, when the size of the furnace becomes large, there is a problem in that the temperature distribution in the furnace will fluctuate even if forced convection is carried out by a fan or the like due to its large volume, and the bond strength will fluctuate.

Further, the method of directly blowing hot air onto the lead frame using a quick-drying silver paste has a problem that the adhesive strength is weak and it is difficult to apply it to a semiconductor chip having a large size.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a method of manufacturing a semiconductor device which shortens the processing time and downsizes the device.

[0012]

FIG. 1 shows an explanatory view of the principle of the present invention. In FIG. 1, in a case where a predetermined object in a semiconductor manufacturing process is subjected to heat treatment in a processing unit, in the first step, a storage unit that is moved to or inside the processing unit is used as the object. Move to the position for storing and taking out. In the second step, the object is sequentially conveyed and stored in the storage section at each processing timing.
In the third step, the heat treatment of the stored object is performed. Then, in the fourth step, after the heat treatment for a predetermined time, the object is taken out of the storage section and discharged from the processing section.

[0013]

As described above, when the object is heat-treated by the processing apparatus, the storage section is moved to the processing apparatus or the storage section disposed in the processing apparatus, and the storage section is set at a predetermined position. The object is moved and stored, and heat treatment is performed for a predetermined time.

That is, it is sufficient for the processing device to have a size capable of disposing the storage portion, and it is possible to reduce the size of the processing device, thereby making it possible to make the internal temperature distribution uniform. In addition, since the object is successively conveyed, stored in the storage section, and subjected to the heat treatment, the waiting time is eliminated and the processing time can be shortened.

[0015]

FIG. 2 shows a block diagram of an embodiment of the present invention.
This example shows an example of a semiconductor manufacturing apparatus in which the method of the present invention is applied to the heat treatment in the die attaching process in various semiconductor manufacturing processes.

FIG. 2 shows a processing apparatus 11 for performing heat treatment in the die attaching process, in which the object to be heat treated has the above-mentioned silver paste as an adhesive agent for the semiconductor chip on the stage. The lead frame 12. That is, dicing is performed by curing the silver paste by heat treatment.

In FIG. 2, the processing apparatus 11 is the above-mentioned curing furnace, and the box furnace 13 which is a processing section covered with a heat insulating wall has a processing chamber 13a and a clip 14 for the processing chamber 13.
It is constituted by a door portion 13b which is fixedly formed by a and 14b.

Heater blocks 15a and 15b are mounted inside the processing chamber 13a and inside the door 13b.
The heater blocks 15a and 1b have fin-shaped (concave-shaped) surfaces to improve heat dissipation, and minute blowouts (not shown) are formed. Three (3) rod-shaped heaters 16 are internally provided.

An air supply hole 17 is formed on the lower side of the heater block 15a. A thermocouple 18 for measuring the temperature inside the furnace and an exhaust port 19 are provided in the processing chamber 13a.

In this box furnace 13, the inside of the furnace is heated by the heater 16 via the heater blocks 15a and 1b. In this case, the outside air is supplied from the air supply hole 17 of the heater block 15a to be heated. Air is blown out from the blow-out holes on the surface of the heater block 15a for convection,
The gas is exhausted from the exhaust port 19 to the outside.

At this time, the temperature inside the furnace is measured by the thermocouple 18, and the heater 16 is controlled based on this to keep the temperature inside the furnace constant and uniform.

On the other hand, the opening 2 is provided at the bottom of the box furnace 13.
0 is formed, and a magazine 21, which is a storage unit for storing a plurality of lead frames 12, is moved from the opening 20 and is placed in the furnace by moving. That is, the box furnace 13
Is a processing chamber 1 in a space where this magazine 21 can be placed.
3a is formed.

This magazine 21 has a moving plate 22 and screws 2
It is attached by 3a and 23b. 2 on the moving plate 22
Book shafts 24a and 24b are attached, and the shafts 24a and 24b are attached to a T-shaped drive member 25 and vertically moved by an elevator 26. The elevator 26 is fixed to a mounting plate 27. Also, shaft 2
Heat-resistant bush 2 is provided on the moving plate 22 side of 4a and 24b
8a, 28b are attached, and the shaft 24
a and 24b are protected.

Although not shown in FIG. 2, a door is formed on the side wall of the box furnace 13, and the lead frame 12 carried by the carrying means is housed in the magazine 21 and taken out and discharged after the processing (see FIG. 3).

In the processing apparatus 11, the magazine 21 is first moved into the box furnace 13 by the elevator 26, and is moved up and down so that the storage area of the magazine 21 is located at the storage position of the lead frame 12 to be transported. ,
The lead frame 12 is housed in this area. That is, the magazine 21 is housed for each lead frame 12 that is sequentially raised or lowered by the elevator and sequentially conveyed at processing timing.

The magazine 21 stores the lead frame 12 in the furnace for a prescribed time for performing the heat treatment, and after the curing is completed, the lead frame 12 is discharged during storage and in the circumferential direction. Then, these operations are repeated for each lead frame 12.

The lead frames 12 of different sizes are also used.
In the case of heat treatment, the magazine 21 is moved to the outside of the furnace by the elevator 26, the magazine 21 is removed from the moving plate by the screws 23a and 23b, and the magazines of different sizes are attached for replacement.

In this way, the box furnace 13 is attached to the magazine 2
Since it can be downsized according to the size of 1,
It is possible to reduce the heater capacity and shorten the rise time from when the power is turned on until the temperature inside the furnace stabilizes at the set temperature. Further, since the curing can be executed in units of the lead frame 12, there is no waiting time, and the processing time can be shortened together with the shortening of the rise time described above.

Further, since the volume of the processing chamber 13a can be made small, the temperature distribution is small due to air convection in the furnace, and the lead frame 12 does not stop at the same position when the magazine 21 moves up and down. There is little drying unevenness, and it is possible to make the bonding state of the die attachment uniform.

Further, the type of lead frame can be changed only by exchanging the magazine 21, and the exchanging work can be facilitated.

Next, FIG. 3 shows a block diagram of an application example of the present invention. FIG. 3 shows an example in which the processing device 11 of FIG. 2 is incorporated in an automatic production line.

In FIG. 3, a heat insulating door 31 which is opened and closed when the lead frame 12 is supplied to or discharged from the magazine (21) is provided on the side wall of the box furnace 13. The heat insulating door 31 is vertically moved by a cylinder 32. Open and close the receiving port. Further, heat resistant bushes 33 are provided on opposite side walls of the heat insulating door 31, and a push rod 34 a of a pusher 34 provided outside extends into the box furnace 13. This push rod 34a is mounted on a magazine (2
It is located behind 1) and pushes out the accommodated lead frame 12 from the rear toward the heat insulating door 31.

In front of the heat insulation door 31 of the box furnace 13,
A guide rail 35a of a movable unit 35 which is movable in the direction of arrow A is arranged and brought into a connected state with a guide rail 36 continuously provided by a die attaching device (not shown). 1 transport unit 3
7 is provided.

A second transport unit 38, which is a transport means, is provided in the discharge movement direction of the moving unit 35, and the guide rail 35a is moved by the movement of the moving unit 35.
Is located. At this time, the guide rail 35a is in a connected state with a guide rail continuously provided to a wire attaching device (not shown).

In such an automatic production line, the lead frame conveyed from the die attaching device is moved by the moving unit 3.
5 from the guide rail 35a to the first transport unit 37 from the heat insulating door 31 to the magazine (2
It is stored in 1). Box furnace 1 for lead frame 12
When the heat treatment for the specified time in 3 is completed, pusher 3
The push rod 34a of No. 4 again takes out the heat insulating door 31 onto the guide rail 35a.

The guide rail 35a is moved to the second transport unit 38 by the moving unit 35 and is moved to the guide rail 3a.
When the lead frame 12 is connected to the wire attaching device 9, the lead frame 12 is transferred to the wire attaching device by the second transfer unit 38.

As described above, by downsizing the processing apparatus 11, it is possible to incorporate the processing apparatus 11 into an automatic production line, it is not necessary to take the product out of the production process, and human error can be prevented. .

In the above embodiment, the lead frame 1
Although the case where the supply and the discharge of 2 are performed from the same direction is shown, the structure may be such that the box furnace 13 is received from the front and discharged from the rear. In this case, the moving unit 35 and the pusher 34 are not necessary, and a heat insulating door may be further provided at the position of the push rod 34a, and the second transport unit 38 may be provided at this position.

[0039]

As described above, according to the present invention, the object is stored in the storage section arranged in the processing apparatus at each processing timing, and the object is heat-treated for a predetermined time and discharged.
The processing time can be shortened and the device can be downsized.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a configuration diagram of an embodiment of the present invention.

FIG. 3 is a configuration diagram of an application example of the present invention.

[Explanation of symbols]

 11 Processing Equipment 12 Lead Frame 13 Box Furnace 15a, 15b Heater Block 16 Heater 17 Air Supply Hole 18 Thermocouple 19 Exhaust Port 21 Magazine 22 Moving Plate 23a, 23b Screw 26 Elevator 31 Heat Insulation Door 34 Pusher 34a Push Rod 35 Moving Unit 37th 1st transport unit 38 2nd transport unit

Claims (4)

[Claims] 1. A method of manufacturing a semiconductor device in which a predetermined object (12) in a semiconductor manufacturing process is heat-treated in a processing section (13), wherein the processing section (13) is moved or placed inside. Moving the storage part (21) to a position for storing and taking out the target object (12), and sequentially transferring the target object (12) to the storage part (21) at each processing timing. And a step of heat-treating the housed object (12), and after the heat treatment for a predetermined time, the object is taken out of the housing section (21), and then processed by the processing section (13). And a step of discharging the semiconductor device. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the object (12) has a semiconductor chip mounted on a lead frame with a predetermined adhesive interposed. 3. A semiconductor manufacturing apparatus in which a predetermined object (12) in a semiconductor manufacturing process is heat-treated in a processing section (13), wherein the semiconductor manufacturing apparatus is moved to the processing section (13) or arranged inside thereof.
A storage section (21) for storing the object (12), a moving means (26) for moving the storage section (21) to a position for storing and taking out the object (12), and the storage section. Conveying means ((21) for sequentially conveying and storing the object (12) at each processing timing, and for taking out and ejecting the object (12) from the storage section (21) after the heat treatment for a predetermined time ( 37, 38), and a semiconductor manufacturing apparatus comprising: 4. The semiconductor manufacturing apparatus according to claim 3, wherein the object (12) has a semiconductor chip mounted on a lead frame with a predetermined adhesive interposed.