JPS59231838A - Method and apparatus for seam welding of vessel for semiconductor device - Google Patents

Abstract

PURPOSE:To seal airtightly a vessel and a rectangular cap uniformly by a method wherein the fact that the extensions of the adjoining two sides of a rectangular cap intersect in order the center of a roller electrode on one side is detected up to time when separate from the peripheral edge of the electrode, and feeding of an electric current is stopped. CONSTITUTION:A vessel 200 covered with a cap 201 is fixed on a base 14 by a jig 202, a cam 210 the same shape with the cap 201 is rotated to descends roller electrodes 50, 51, and both the edges of the cap 201 are pressed according to the prescribed pressure to perform a temporary welding. When the base 14 and the cam 210 are rotated next, pinch rollers, 31, 32 follow up the rotation of the cam 210, the roller electrodes 50, 51 are also rotated, and the contact positions of the electrodes are fixed to fix a welding current. The base 14 is rotated up to the scheduled position to flow the current to the electrodes 50, 51, and sides AB, A'B' of the cap 201 are welded. At time when the extension of the side C'B passes the center of the electrode 50 is detected 230 by the front edge 221a of the notch of a disk 220, the current is stopped, and at time when the side C'B separates from the peripheral edge of the electrode 50 is detected by the rear edge 221b of the notch, the current is fed again to weld the sides BC, B'C', and overheating of the corner part of the cap is checked. After seam welding of the whole periphery is completed by performing the process similarly hereafter, the current is stopped, and the electrodes are separated from the cap to complete the process.

Description

[Detailed description of the invention]

The present invention relates to a seam welding device, and particularly to a semiconductor device,
The present invention relates to a welding device for seam welding a cap and a container covering a circuit element in the manufacture of semiconductor integrated circuit devices (ICs) and the like. In general, square or rectangular so-called square containers are often used as containers for semiconductor devices because they can efficiently accommodate circuit elements at a high density. As a device for overlapping and seam welding the same rectangular cap on this square container, the present applicant previously applied for patent application No. 56-1.
74078 No. 1-7-Member welding equipment for containers for semiconductor devices”
proposed. This device places a container for semiconductor devices on a rotating table, overlays a cap on the container, rotates a cam that has the same shape as the cap to be welded, and creates a pair of cams that correspond to the movement of each side of the cam. Following the movement of the conical roller electrode, the roller electrode is constantly brought into contact with the periphery of the cap whose seating position changes by rotating the table, and the roller electrode is energized at a constant pressure at a contact movement speed with respect to the cap. By doing so, the container and the cap are hermetically sealed. This device will be further explained using FIGS. 1 to 3. FIG. 1 is a plan view of the seam welding apparatus, and FIG. 2 is a cross-sectional view of the portion indicated by the line ■-■ in FIG. 1. Referring to FIGS. 1 and 2, especially FIG. 2, 1 is an electric motor, a pulley 2 is pivoted to the motor 1, and a pulley 4 of a clutch brake 3 is provided adjacent to the motor 1.
are connected by a timing belt 5, and transmit the rotational motion of the motor 1 to a worm 6 that is pivotally attached to a clutch brake 8. The worm 6 is connected to the base 7 by a timing belt II via a pulley 10 which is perpendicular to the base 7 and rotatably fixed near the middle of the support camshaft 8.
Goo 9 of the table shaft 12 rotatably supported perpendicular to
13 will be informed. Climb table nl+12. On the other hand, referring to FIG. 8, a rectangular cap 201 of the semiconductor device container 200 to be seam welded is attached to the upper end of the camshaft 8.
A cam 210 of the same shape is fixed, and a pinch

[Pulley mounting 111129.30 is supported by the first and second moving plates 27 and 2g vertically by 1μ and rotatably +I'lb. This pinch roller installation Ii+1+29.3o F
Pinch rollers 31 and 82 are fixed to each end. The cam 210 is clamped from both l1111 by the pinch rows 231.82. Pinch roller mounting shaft 2
9. End IC iJ: Pulley 33, 34 is fixed, timing bell) 85, 36 (Fig. 1, R
from the table 14 through the supports 37, 38 (Fig.
The rotational force of the pinch rows 231.32 is transmitted to pulleys 42, 43 rotatably provided on arms 40.41 extending horizontally above. A spline shaft 46.47 (FIG. 2) is inserted into the pulley 42.48, and this spline +111146.47 rotates together with the pulley 42.48 and can also slide vertically. A pair of power supply shafts 48 are electrically disconnected and connected to the lower ends of each of the spline shafts 46 and 47 configured in this way, and a roller electrode in the shape of an inverted truncated cone is provided at the lower end of each power supply shaft 48. 50.51 is fixed. Clamps 52 and 53 are loosely fitted to the middle portion of the power supply shaft 48, and welding current is supplied to the power supply shaft 48 via a pair of jumpers 56 connected to a welding power source (not shown). Further, the clamps 52, 53 are configured such that the pressing force is controlled by a motor 70, 71, and are respectively fixed to electrode elevator devices 60, 61 extending from the columns 37, 88 to the soil of the table 14. The welding rods 80 and 81 constructed as described above are attached to the fixed blocks 82 and 88 (Figs. 1 and 2) on the base 7.
Horizontal guide guide 184.85 and fixed block 82
．． Fixed blocks 86 and 87 (
They are fixed on moving blocks 90, 91 and 92, / 93 (see Fig. e) which are slidably inserted into guide shafts 88, 89 which are horizontally mounted on the guide shafts 88, 89 (Fig. 7), and thereby move these guide shelves onto the table 14 You can approach or retreat towards the center of the area. Welding on the lower surface of the moving plate 28 toward the center of the table 14 ~
＼1″80 trigrams ↓bi l+ 1 'It, ts
/rth tension adjustment mechanism is provided.
j Dye 4j Q 4.1: s Bins 113 and 114 (Fig. 1) planted on the lower surface of the moving plate 28, and bottles 115 and 116 (Fig. 2) planted on the lower surface of the other moving plate 27. Tension coil spring with variable tension between 117.11
8 is stretched, and welding heads 80 and 81 are mounted on table 1.
It is pulled towards the center of 4. kI′ of this tension
The i node is connected to the rotation of the cam 210 by the pinch rollers 31 and 3.
2 is performed in order to reliably follow and rotate without causing slippage or the like. During seam welding, the pinch rollers 81 and 82 rotate as the cam 2100 rotates, but when the rectangular cup 210 rotates at a constant speed, the cam 21 of the pinch roller 81 and 82 rotates.
The contact movement (rotation) speed with respect to 0 and the contact movement speed of the roller electrodes 50 and 51 with respect to the cap 201 on the semiconductor device container 200 are different,
The welding current density per unit time υ at each part of the periphery changes. For this reason, uniform welding cannot be performed around the entire circumference of the cap 201. Therefore, by converting changes in the distance from the center of the cap 201 to each side into changes in electrical resistance, and changing the rotational speed of the motor 1, a part of the corner of the cap 201 and its vicinity come into contact with the roller electrodes 50 and 51. The contact movement speed when doing so has been slowed down. That is, when the cam 210, which has the same shape as the cap 201, rotates and the vicinity of a part of the corner of the cam 210 comes into contact with the pinch rollers 31 and 32, both the pinch rollers 81 and 32 are pushed outward, and the pinch rollers 81 and 32 are pushed outward. 8
The movable plates 27 and 28 to which the numbers 2 are respectively fixed also move in the same way. Movement of the moving plates 27 and 28 from the center of the cam 210! Since fIIJ ft is the same, the purpose can be achieved by detecting the amount of movement of one of the moving plates. In this embodiment, the bins 121 are installed at appropriate positions on the moving block 93 to which the eight moving plates 28 are fixed, and the base 7''
Secondly, a displacement detecting transducer fixed perpendicularly to the pinot 121 is coupled to the sliding shaft 123 of the meter 122, for example, a potentiometer. The potentiometer 122 is a slide shaft 128
(insertion of )", that is, the digit 1 of the moving board 28? Since it outputs an electric current fE proportional to the change in f, the rotational speed of the motor I can be controlled by this voltage. According to the boom welding device constructed in this way, a pair of roller electrodes are constantly brought into contact with a rectangular cap that is placed on the tabletop and rotates, and the movement of the roller electrodes during this contact is used to weld the rollers. Since the contact movement speed of the electrode with respect to the cap is kept constant, the welding current fA per unit time IN at each point on the circumference of the cap can be made constant, so a uniform nugget can be obtained and the welding area (,
Y productivity is increased and a beautiful welded appearance can be obtained. However, if the contact time of the roller electrode to each part of the cap is constant and the current is applied continuously, the MM in the straight part of the rectangular cap will be constant, but the i-bar heating will occur in a part of each corner, causing the contact of the cap to There was a drawback that a portion of the product melted too much, impairing the airtightness of the container for semiconductor devices, leading to product defects. However, if oval heating occurs, there are acid points that naturally cause the electrodeposition to burn out. The purpose of the present invention is to uniformly heat the entire circumference of a semiconductor device container (hereinafter referred to as a square IC package) made by overlapping rectangular caps, and thereby hermetically seal the entire circumference of a square IC package. An object of the present invention is to provide a method and apparatus for seam welding a semiconductor device container that can be stopped. In the method and apparatus for welding a container for semiconductor devices according to the present invention, a rectangular cap is superimposed on the top of the container for semiconductor devices, and a pair of rollers 1! The electrodes are brought into contact and the pair of roller electrodes are rotated relative to the semiconductor device container and the rectangular cap, and the movement of the roller electrode at the time of contact is used to keep the speed of contact movement of the roller electrode with respect to the cap constant and energization. (semiconductor device) 11 In a method of seam welding the container and the rectangular cap, extension lines of any two mutually adjacent sides of the rectangular cap sequentially intersect with the center of one roller electrode and The roller electrode is characterized in that a detection means detects the time until it leaves the peripheral edge of the roller electrode, and the energization is stopped by a energization temporary stop means that operates based on a detection signal from the detection means. The details of the present invention will be explained below with reference to FIGS. 4 to 8. FIG. 4 is a longitudinal sectional view of the cap position detection means for detecting the position of the rotating cap according to the present invention, and FIG. 5 is a sectional view taken along the line v-vg in FIG. 4. In these figures, the same reference numerals are used for the parts corresponding to FIGS. 1 to 3, and detailed explanations will be omitted. In FIG. 4, reference numeral 220 denotes the upper end of the camshaft 8 that transmits the rotation of the morph 1, and the rectangular cap 201 of the container 200 for semiconductor devices to be welded.
This is a cap position detection disk fixed between a cam 210 of the same shape as (ffi2). As shown in FIG.
A position detector 230 consisting of a light source section 231 such as a light emitting diode and a light receiving section 232 such as a photodiode U is provided at an arbitrary position on the rotation locus of the cap position detection disk 220. Notch part 2
21 to 224 are detected respectively, and a detection signal is output to energization temporary stop means 240, which will be described later. The notches 221 to 224 of the cap position detection disk 220 are formed so that the extension lines of any two adjacent sides of the cam 210 intersect with the center of one of the pinch rollers 31 or 32 in sequence υ and the pinch roller 3I or from the circumference R1t% of 32 to the point where the gap 2 of the rectangle 2 (the extension of any two sides touching each other tt of 11) intersects with the center of one of the roller electrodes 50 or 51 and the corresponding roller 1
! The portions of the poles 50 or 51 until they are separated from the circumferential H portion are cut out. Incidentally, the rectangular cap 201
is a square with a side of 1λ7 mm #! 3@ as an example, the notches 221 to 224 are 34°06' to 55°5
4', 124°06' to 145°54', 214°06
'~255°54' and 304°06'~325°5
It is provided by cutting out between 4'. Notches 221 to 224 (first
)l:i') detection signal C111, AC welding power source 3o'6"'ic
``Electrification temporary stop means 240 that controls energization with four legs 11
is input. In the AC welding power source aOO, voltage is applied to a switching circuit 302 formed by an SCR through an AC TIc source terminal 801, and a pulse signal from a relaxation oscillation circuit 308 is applied to a switching circuit 302 formed by an SCR. to the switching circuit 302 through the gate of the SCR whose 7 nodes are positive with respect to the cand).
When a positive pulse is applied to K, the SCR conducts and is arranged to remain conductive until the end of a half cycle of the applied voltage. Note that 305 is a synchronizing signal generating circuit, and 306 is an output l/las. The energization temporary stop means 240 is composed of, for example, a bistable multi-pipe rake (hereinafter referred to as bistable multi), and is connected to the position detector 23.
The detection signal from 0 is applied to the bistable multi 240 as a energization temporary stop signal, and the bistable multi 240, which is being driven by a separate starting pulse, is reversed to the low 5-'l pole 5.
When the power supply to 0 and 51 is stopped, the position detector 23
The energization restart signal from 0 is added to the bistable multi 240.
, the bistable multi 240 is reversed and applies an oscillation start signal to the relaxation oscillation circuit 308, and welding current is applied. The above operations are performed similarly for each of the notches 221 to 224, but it is sufficient to seam weld the entire circumference of the cap 20 by rotating the table 14 by 1.80 degrees.
One gap weld is performed using notches 22 and 222, and further welding is performed using notches 228 and 22.
4 can be used to seam weld other caps. The operation of sealing a semiconductor device container and a rectangular cap using the above-described seam welding apparatus for a semiconductor device container will be described below. □ First, on table 14 soil, cap 201? , 1 stacked semiconductor device containers 200i are fixed using an appropriate jig 202 and formed into the same shape as the cap 201. When the cam 210 is fixed to the cam shaft 8 and the switch is turned on, the roller electrode 50° 51 is lowered by the force of the motor 70.7J, the micro switch provided in the pole lifting mechanism 60.61 is turned off, and the rotation of the motors 70 and 71 is stopped. Rotate the daple 14. When the cam 210 rotates, the pinch rollers 3] and 82 rotate following this rotation, and the pulleys 88.8
4. Timing belt 35.36 and pulley 42.4
The roller electric motors 4Fj50 and 51 also rotate through the rollers 3 and 3. After that, when the table 14 rotates at a predetermined rotational position of 161 inches, a roller electric current (welding current is applied between t50.51 and
In order to weld the entire circumference of the semiconductor device container 200 and the cap 201, the mold is passed through the mold by 180° from this position 4. This energization process will be explained in more detail with reference to FIGS. 7 and 8. Fig. 7 is a diagram showing the relationship between the cap 201 and the roller electrode 50.51 during intermittent seam welding, and shows the relationship between the cap 201 and the roller electrode 50, 51, and the welding chamber 1 during intermittent seam welding. It is a figure which shows a part of fU waveform. In FIG. 7(,), the tack welding is φ when the roller electric clamps 50, 51 are lowered and reach a predetermined pressing force. 7-m welding was started approximately 0.5 seconds after the welding was completed, and at the 71st inch/1, points A-B and A'-B', which were located on the cap 201 for convenience of explanation, were welded. The extension 0 of the side B-C of the cap 201 is the roller electrode 5.
0, that is, when the rotation angle of the gap 2010 reaches 84°06', the position detector 230 detects the gap position detection disc 220 at the front fi2 of the notch 221.
21a is detected and the welding current is stopped (FIG. 7b). This energization stop occurs when the side B-C' of the cap 201 adjacent to the side B-C is the roller'? i, when leaving the periphery of the pole 50, i.e. the rotation angle of the gap 201 is 55°5
4' (Fig. 7C). By stopping the energization, it is possible to prevent the corners of the cap 201 shown as B and B' from overheating. When the rotation angle of the cap 201 reaches 55°54', the position detector 230 detects the rear edge 221b of the notch 221.
is detected, the energization is restarted, and the side B-C of the cap 201 is
and R'-C' are welded. The rotation angle during this time is 55
°54' to 124°06'. Similarly, when the extension line of the side B'-C of the cap 201 crosses the center of the roller electrode 50 (FIG. 7d), the side B-C adjacent to this side B'-C is the periphery of the roller electrode 50. The current supply is stopped again until the cap 201 is separated from the cap 201 (FIG. 7e), that is, the rotation angle of the cap 201 is between 124°06' and 145°54'. By stopping the current supply, overheating of the remaining corners of the cap 201 indicated as C and C' can be prevented. Furthermore, when the rotation angle of the cap 201 reaches 145° 54', the current is applied to weld the sides C-A' and C'-A of the gap 201, and the semiconductor device container 200 and the rectangular cap 201 are welded together. Completed seam welding around the entire circumference. Cap 2 for this remaining period
The 010 rotation angle is from 145°54' to 180°. However, in reality, for the purpose of completely airtightly sealing the container 200 and the cap 201, the final and first chambers are slightly overlapped, that is, the rotation is not stopped at 180° but rotates from 188° to 185°. It is desirable to extend it somewhat. In this way, when welding of the entire circumference of the cap 201 is completed, the welding current is turned off and at the same time, the motor 70 is operated to remove the welding from the gap 201. The whole process is finished by leaving 50.51 to -ler p+, , 1. , :+,i, To set the starting point of the welding current, connect an encoder (not shown) to the table 14 to accurately detect the rotation angle of the table 14, and set the starting point of the welding current. is set in advance, and when the table 14 rotates to the set angle, the welding current is applied to the roller electrode 50.5].
can be supplied to This configuration is convenient because the welding start position of the cap 201 can be determined accurately. As is clear from the above description, the device i? according to the present invention?
, are pinch rollers 81 and 8 as the cam 210 rotates.
As the roller electrodes 50 move toward or retreat toward the center of the cam 210 while following and rotating together, the roller electrodes 50
．． 51 are also linked in the same manner, and the contact position of the roller electrode 50.51 with the periphery of the cap 2010 can be kept constant, and the density of the welding current flowing from the roller electrode 50.51 to the cap 201 is constant, so that welding can be performed. You can get enough nuggets. Further, since the contact position 111 of the roller electrode 50.51 with the peripheral edge of the cap 2010 is constant, the conical part (poison gland part) of the truncated conical roller electrode 50.51 can be shortened, and the cap 201 Even if the semiconductor device container 200 is smaller, the tips of the roller electrodes 50 and 510 do not come into contact with the container 200, so the semiconductor device container 200 will not be damaged. Furthermore, the rectangular cap K, which is placed on a table and rotates, is brought into constant contact with a pair of roller electrodes, and the movement of the roller electrodes during this contact is used to keep the contact movement speed of the roller electrodes with respect to the cap constant. Since the amount of welding current per unit time at each point on the circumference of the cap 201 can be made constant, a uniform nugget is produced, which increases the reliability of the welded part and provides a beautiful circular welded appearance. can. Furthermore, a cam with the same shape as the gear and cap to be welded is rotated, and the movements of the pair of conical roller electrodes are imitated by the movement of each side of the gear, so that the workpiece (cap)
Even if the welding process changes, new welding work can be performed simply by replacing the cam, making it easy for even unskilled wireworkers to handle and improving productivity. Furthermore, when the rotation of the cap 201 and the roller electric motor are forcibly moved relative to each other, it has all the effects that conventional devices have, such as welding and speeding up the vehicle speed. Some of the new effects include preventing heat and uniformly heating the entire circumference of the cap 201 to make the entire circumference of the square IC package airtight. Obtainable.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a conventional seam welding device for containers for semiconductor devices, Fig. 2 is a cross-sectional view of the part indicated by n - n legs in Fig. 1, and Fig. FIG. 4 is a longitudinal sectional view showing the electric temporary stop position detector, and FIG. 5 is a sectional view of the portion indicated by the line ■-■ in FIG. 4. , FIG. 6 is a block diagram showing the circuit configuration of the seam welding device for semiconductor device containers according to the present invention, and FIG. 7 is an IX type diagram showing the positional relationship between the cap and the roller electrode during seam welding using the device of the present invention. 8 is a diagram showing a part of the welding current waveform during intermittent welding in FIG. 7. 14...Table, 31.32 "Nochirola 1.5"
0, 51-O-ra@4”+s 200 Container for semiconductor T, 201... Cap, 210... Cam, 220
...Cap position detection disc, 230...Position detector, 240...No.41 electric temporary stop means, 800...AC welding power source OR1 Applicant: Japan Avionics Co., Ltd. Figure 5 220 2213 7th Flash

Claims (3)

[Claims] (1) A rectangular cap is placed on top of the semiconductor device container, and a pair of roller electrodes are brought into contact with the peripheral edges of the two points with different gaps to connect the semiconductor device container, the rectangular cap, and the pair of roller electrodes. While rotating relatively, the roller electric 4' at the time of this contact! In the method of seam welding the semiconductor device container and the rectangular cap by applying electricity while keeping the contact movement speed of the roller electrode constant with respect to the gap using a movement of i, the rectangular gaps are adjacent to each other. A seam of a container for a semiconductor device, characterized in that the current supply is stopped between the points where extension lines of any two sides intersect with the center of one roller electrode by 1 inch and are separated from the peripheral edge of the roller electrode. Welding method. (2) Place a rectangular cap on top of the semiconductor device container and place a pair of roller electrodes in contact with two different peripheral edges of the cap. By relatively rotating the semiconductor device container and the rectangular cap and the pair of roller potentials, and using the movement of the roller electrode at the time of contact, the contact movement speed of the roller electrode with respect to the cap is kept constant and energization is applied. In an apparatus for sheet-welding a semiconductor device container and the rectangular cap, the extension υ of any two mutually inscribed sides of the rectangular cap sequentially intersects with the center of one of the roller electrodes, and the roller A container for a semiconductor device 119, characterized in that it is equipped with means for detecting the difference between 1 and 1 emitted from the peripheral edge of a potential electrode, and means for temporarily stopping energization based on a detection signal from the detection means. 7~mu welding equipment. (3) The detection means sequentially detects the distance between the extended lines of any two mutually descending sides of the rectangular cap until they intersect with the center of one of the row electrodes and separate from the periphery of the roller electrode T-pole. The semiconductor device calendar according to claim 2, characterized in that the device comprises a notched disk that rotates in synchronization with the rotation of the cap, and a detector that detects the notched portion of the disk. Lunar vessel seam welding equipment.