JP3099775B2 - Heat rail device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat rail of a die bonder for assembling a semiconductor pellet to a lead frame in a semiconductor device manufacturing process, and more particularly to a heat rail device which facilitates maintenance such as cleaning.

[0002]

2. Description of the Related Art In some cases, solder is used to assemble semiconductor pellets (hereinafter simply referred to as pellets) on a lead frame. Au · S with relatively high melting point as solder
A hurdle solder such as an i-alloy may be used, or a soft solder mainly composed of lead and tin having a relatively low melting point may be used. In any case, a lead frame is provided on a heat rail with a lead frame provided thereon. The solder is fed at a predetermined position and heated, and the solder is supplied at a predetermined position. Thereafter, the pellets are placed at the predetermined position. Since the lead frame is heated in this way, it prevents the lead frame and solder from being oxidized, resulting in inadequate assembly of the pellets and hindering the wire bonding between the pellet and the lead frame in subsequent steps. For this purpose, the heat rail device is configured such that the lead frame is transported in a tunnel shape. Except for the entrance and exit of the lead frame, and the minimum space for supplying solder and pellets, the lid plate that forms the tunnel as tightly as possible is tightly fixed.
An inert gas such as a gas is introduced and discharged from the above-not-blocked place to prevent oxidation.

[0003]

In the conventional heat rail device, the cover plate is firmly fixed to the heat block having a U-shaped cross section with screws or the like. It was troublesome to disassemble at the time of trouble such as clogging of the frame, or at the time of cleaning to remove dust and solder debris generated from sliding parts after long use even if it is operating well. further,
Due to the presence of the lid plate, the operating conditions and the flow of the solder could not be observed on the spot, and some time was required for troubleshooting. Therefore, it is desirable to use a transparent material such as heat-resistant glass or quartz glass for the lid plate. However, such a material is difficult to process, and if it is formed into a complicated shape such as screw holes for mounting, it will be expensive, and such a material will be broken. It was easy to use, and maintenance was frequent.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a heat block having a U-shaped cross section by covering the concave portion with a cover plate to form a tunnel, and introducing an inert gas into the lead frame. In a heat rail device for transporting and heating the inside of the tunnel and assembling the semiconductor pellets, a heat groove device is provided with a float groove for forming a gas curtain so as to blow up the lid plate on a top surface of a side wall portion of the heat block forming the recess. The present invention provides a heat rail device in which the cover plate is not fixed and is provided in a free state. According to the above apparatus, since the lid plate is not fixed, it is easy to remove the lid plate when cleaning the inside of the tunnel or coping with a trouble in the tunnel.

Further, there is provided a heat rail device in which a cover plate is made of a transparent material. According to this device, the in-situ observation in the tunnel is possible, and it is possible to appropriately cope with abnormalities in the performance such as maintenance timing and operation status such as more appropriate cleaning and the flow condition of the solder.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing a state in which a cover plate is partially cut away, FIG. 2 is a front view showing a cross section taken along line AA of FIG.
FIG. 2 is a side view of a cross section taken along line BB of FIG. 1. In the heat rail device 1 of the present invention, a heat block 3 having a concave portion 2 has a main portion 3a on the lower side of the concave portion 2 and side walls 3 on both ends thereof.
b and 3b are arranged in a U-shaped cross section in a direction in which the upper side is opened. On the outer side of the top surface 3c of the side wall portion 3b, stoppers 3d for regulating the position of a lid plate 4 described later in the horizontal direction
3e. Further, a plurality of cartridge heaters 5 are embedded in the main portion 3a to heat the heat block 3.
Further, a gas inlet 6 for introducing an inert gas is provided outside the main part 3a, and a flow path 6a formed in the main part 3a therefrom.
An inert gas such as N2 gas is introduced into the recess from the bottom of the recess 2a through the recess.

The side wall 3b is provided with an inert gas flow path 7a over substantially the entire length, although both ends are closed, and outside the side wall 3b, there are provided inert gas introduction ports 7, 7 connected thereto. ing. The top surface 3c is provided with a float groove 3f, and the bottom surface thereof is provided with a gas flow path 7a.
And an ejection port 7b from which an inert gas is ejected is provided at an appropriate pitch.

A lid plate 4 is arranged on the top surface 3c. In FIG. 1, the cover plate 4 is partially cut away, but is actually rectangular in shape and covers almost the entire heat block 3. The cover plate 4 has a hole 4a for supplying solder, Hole 4 for stirring the solder to improve the flow
b, holes 4c for supplying and assembling the pellets are provided at predetermined positions corresponding to the types. And lid plate 4
Is kept floating by the inert gas blown out from the float groove 3f.

An adapter rail 8 is arranged on the bottom surface of the concave portion 2 of the heat block 3 so as to cover almost the entire surface. The adapter rail 8 has a rectangular dish shape with a concave portion facing downward, and a space is formed between the adapter rail 8 and the bottom surface of the concave portion 2 of the heat block 3 to form a tank 9 for storing an inert gas. In addition, ventilation holes 8a that pass upward from the tank 9 are arranged in the adapter rail 8 in a distributed manner.

A tunnel 2a is formed by the adapter rail 8, the cover plate 4, and both side walls 3b of the heat block 3, and a feed rod 10 is provided through the tunnel 2a. The feed rod 10 has a plurality of feed claws 10a at predetermined intervals with their tips directed downward. Then, a lead frame (not shown) on the adapter rail 8 is engaged with the feed hole, and is sequentially conveyed rightward in FIG. 2 by a square operation.

According to the heat rail device of this embodiment,
The inert gas introduced from the inert gas inlet 6 passes through the flow path 6
a, the inside of the tunnel 2a is made an inert atmosphere through the tank 9, and the ventilation hole 8, and is discharged from the entrance and the exit of the tunnel 2a, so that the lead frame and the solder are heated without being oxidized. Then, the inert gas introduced from the inert gas inlet 7 is blown out from the float groove 3f through the flow path 7 and the blow-out hole 3b to blow up the lid plate 4 so as to lift it up. Escape into 2a contributes to keeping the inside of the tunnel inert. Even if the lid plate 4 and the top surface 3c of the side wall of the heat block 3 are not air-tightly fixed, the outside air is not sucked into the tunnel by the inert gas curtain blown up from the float groove 3f.

According to this embodiment, since the cover plate 4 is not fixed, the cover plate 4 can be easily removed, so that the inside of the tunnel 2a can be easily cleaned, and a countermeasure and adjustment for trouble in the tunnel can be easily performed.

Further, if the cover plate 4 is a transparent plate such as a heat-resistant glass plate or a quartz glass plate, the operation at the time of normal operation and the flow state of the solder can be observed on the spot, and more appropriate maintenance can be performed. .

[0014]

As described above, according to the present invention, it is possible to provide a heat rail which can secure both an inert atmosphere in a tunnel and easy maintenance without fixing a cover plate.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

[Explanation of symbols]

 2 Concave portion 2a Tunnel 3 Heat block 3b Side wall portion of heat block 3c Top surface of side wall portion of heat block 3f Float groove 4 Cover plate

Claims (3)

(57) [Claims] 1. A heat block having a U-shaped cross section covered by a cover plate to form a tunnel, and a lead frame is transported and heated in the tunnel while introducing an inert gas to assemble semiconductor pellets. In rail equipment,
A heat rail device, comprising: a funnel that forms a gas curtain so as to blow up the lid plate on a top surface of a side wall portion of the heat block that forms the concave portion, wherein the lid plate is provided in a free state without being fixed. 2. The heat rail device according to claim 1, wherein the gas forming the gas curtain is an inert gas. 3. The heat rail device according to claim 1, wherein said cover plate is made of a transparent material.