JP2001358159A - Jig structure for assembling and manufacturing semiconductor device, and method of assembling the semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove faults generated by the inclination of a shelf in the conventional sealing process of a liquefied resin, on which a tray for baking installed in a baking furnace is positioned. SOLUTION: The sealing process, using the liquefied resin for the semiconductor device uses, a horizontal base, having a structure in which through-holes having three screw threads are formed into thick horizontal plates (35), which hardly deform by heat, and three balancing-adjusting screws (34) are driven into the holes when a semi-finished product, on which a semiconductor chip is loaded, is coated with sealing resin and the sealing resin is thermoset in the baking furnace. The horizontal base and the mounting surface of the baking furnace can be balanced, by adjusting the length of the balancing-adjusting screws projected from the horizontal plates. The tray for baking, on which the semi-finished product is placed, is loaded on the horizontal base, and the resin is thermoset by baking in the baking furnace. Accordingly, the surface of the sealing resin can be leveled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device assembling method and a jig for assembling and manufacturing a semiconductor device in a sealing step using a liquid resin.

[0002]

2. Description of the Related Art There is no known example of a jig structure and a manufacturing method of a conventional liquid resin for a semiconductor device, which have been published in literatures, academic journals and the like. However, a conventionally used manufacturing method and related equipment will be described with reference to FIGS. 1, 2, 3, and 4. FIG. FIG. 1 shows a general-purpose baking furnace 1 used for thermosetting a thermosetting liquid resin. This baking furnace 1
In order to obtain the balance, three or four balance adjustment legs 4 are attached to the lower part of the baking furnace 1. The balance of the baking furnace 1 is obtained by adjusting the balance adjusting leg 4. The balance of the shelf 2 on which the sample in the bake furnace 1 is mounted
It is not possible to determine the balance of this shelf after the equipment has been introduced, only by adjusting it during the production. The inclination of the shelf 4 greatly changes depending on the inclination of the surface on which the bake furnace 1 is installed. FIG. 2 shows an example when the inclination becomes large. In FIG. 2 shown in an extreme expression, the balance of the internal shelf 6 varies from shelf to shelf. On the shelf 6, a baking tray for actually placing and curing the bake sample is placed. FIG. 3 shows the state of the shelf with the balance being taken. FIG.
Describes the state of the shelf with a certain inclination. As shown in FIG. 3, a bake sample (semiconductor device) 10 coated with a thermosetting liquid resin is mounted on a baking tray 11. A baking tray 11 on which a bake sample (semiconductor device) 10 is mounted is placed on a shelf 12 having a good balance. However, when the baking tray 14 is placed on the inclined shelf 15 as shown in FIG. 4, the baking tray 14 also inclines due to the inclination, and naturally the bake sample (semiconductor device) 13 also inclines. However, bake sample 1
The liquid resin applied to 3 is horizontal with respect to the installation surface irrespective of the inclination of the shelf 15. In other words, the resin surface is not parallel to the package surface but is cured while the resin surface is going to be horizontal with respect to a surface having a certain angle.

FIG. 5 shows an example of the cross-sectional structure of a cured bake sample when the package surface and the shelf surface of the baking furnace are parallel. FIG. 6 shows an example of a cross-sectional structure of a bake sample after the resin is cured when the package surface and the shelf surface of the bake furnace are not parallel. In FIG. 5, the liquid encapsulating resin 19 before being hardened is the semiconductor device package 2.
Curing while trying to keep horizontal with respect to the flat surface on the back of 1. As a result, the highest portion of the encapsulating resin 19 is placed at the center of the semiconductor package 21 in the semiconductor chip 2.
3 is near the center. In this case, the difference between the highest point of the sealing resin 19 and the highest point of the solder ball 16 is called a standoff 18. Next, the inclination of the encapsulating resin that occurs when the baking tray or shelf is inclined as shown in FIG. 6 will be described. The resin encapsulating surface is formed so that the fluid encapsulating resin before curing does not attempt to be level with a shelf or a baking tray and is parallel to the installation surface on which the baking furnace is placed. In the case of this sample, inclination occurs with respect to the flat portion on the back surface of the semiconductor device package 30. For this reason, the highest position of the sealing resin 28 does not come to the center of the semiconductor chip 23 as shown in FIG. 5, and the sealing resin is shifted to the right or left of the semiconductor chip 32 as shown in FIG. Due to this shift, the resin thickness of the encapsulated resin becomes the highest at the highest position. A comparison between the standoff 18 in FIG. 5 in which the resin thickness is changed so that the resin thickness changes evenly from the vicinity of the center of the semiconductor chip and the standoff 27 in FIG. 6 in which the resin thickness is locally increased by a certain inclination is shown. OFF 27 is smaller.

[0004]

The first problem here is that the liquid resin having fluidity at the time of thermosetting of the resin encapsulation picks up the inclination of a baking furnace, a baking shelf or the like, and the enclosing surface is partially inclined. The height of the resin is too high to make the standoff large.
Due to this phenomenon, when this package is mounted on a printed circuit board, the locally protruding resin surface hits the printed circuit board, and there is a distance between the solder balls around it and the solder paste on the printed circuit board pattern, and in the solder reflow process This means that the package and the printed circuit board are not connected well and are disconnected. In particular, in recent years, with the miniaturization of semiconductor devices, even a small inclination of a baking furnace or a baking shelf has become a serious problem with respect to the size of the semiconductor device.

[0005] The second problem is that the inclination of the baking furnace or the inclination of the shelf changes with the aging of the baking furnace, thereby changing the flatness of the resin surface and changing the shape of the semiconductor device. It is. For this reason, there is also a problem that much cost and time are required for inspection and maintenance of the device. In particular, when using at high temperatures, such as in a baking furnace, the materials that make up the shelves age quickly and the baking furnace repeats the temperature cycle from low to high by repeating the baking operation. The aging is accelerated by the expansion and contraction of the material constituting the inside of the baking furnace such as a shelf.

<Object of the Invention> The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to make it possible to make the sealing resin surface horizontal with respect to the back surface of the semiconductor device so that the solder ball The standoff between such external terminals and the resin surface can be controlled within the design value or the standard value, which can improve productivity and the production rate of non-defective products, and also confirms the levelness every time the resin is filled. It is possible to improve the economics and workability by observing the change in shape due to the aging of the device, changing the conditions, etc., and eliminating the need for inspection, time, and costly maintenance. An object of the present invention is to provide a semiconductor device assembling method and a jig for assembling and manufacturing a semiconductor device.

[0007]

In a sealing step using a liquid resin of a semiconductor device, when a sealing resin is applied to a semi-finished product on which a semiconductor chip is mounted and the sealing resin is thermally cured in a baking furnace, A thick horizontal plate that is less likely to be deformed by heat is provided with a through hole having three threads, and a horizontal base having a structure in which three balance adjusting screws are screwed into this hole is used. By adjusting the length of the balance adjusting screw protruding from the horizontal plate, the balance between the horizontal base and the installation surface of the bake furnace can be obtained. The baking tray on which the semi-finished product is placed is mounted on the horizontal table, and the resin is thermally cured by baking in a baking furnace. Thereby, the sealing resin surface can be made horizontal.

<Operation (Function of Means for Producing Effect)> The horizontal base of the present invention has a through hole provided with a screw thread in a flat horizontal plate having three balance adjustment screws thick. It has a turned-in structure. By turning this screw, the length of the screw that goes down from the horizontal plate can be changed. The horizontal table is placed on a shelf in a baking furnace, and a level is placed vertically in the center of the horizontal table. Adjust the length of the adjusting screw coming out of the horizontal base while checking the air bubbles in the level, and confirm that the air bubbles in the level are located at the center and the baking furnace and the installation surface are horizontal. Next, place the level horizontally on the center of the horizontal base and adjust the adjusting screw so that the air bubble is centered in the same manner. This operation is repeated to adjust the level so that the bubble of the level is at the center regardless of whether it is vertical or horizontal on the horizontal table. Thereby, the horizontal plate surface of the horizontal base and the installation surface on which the baking furnace is installed become horizontal. A baking tray on which a semi-finished product of a semiconductor device coated with a liquid sealing resin is mounted thereon.
Close the bake oven door gently and bake at the desired temperature. By performing the above operation, the sealing resin surface is kept horizontal with respect to the surface of the semiconductor device package, the resin is partially shifted in the direction in which the resin is present, and the thickness of the resin is partially increased. The non-defective interval, that is, the standoff does not satisfy the design value and the standard value, and the non-defective product rate can be increased. In addition, by adjusting each time in the enclosing process, the aging of the baking furnace, the deformation and inclination of the shelf can be confirmed in advance, and the enclosing can be performed without being affected by the deterioration. In the past, if the standoff did not satisfy the standard and design values due to the aging of the baking furnace and the shelf, it was necessary to replace or repair the parts such as the shelf. However, durability can be improved by using the horizontal base of the present invention.

A jig for assembling and manufacturing a semiconductor device according to the present invention is a jig for assembling and manufacturing a semiconductor device used in a sealing step of using a liquid resin for a semiconductor device, wherein the jig has a semiconductor chip mounted thereon. When a sealing resin is applied to a product and the sealing resin is thermally cured in a baking oven, a through hole having three threads is provided on a thick horizontal plate that is less deformed by heat, and three holes are equilibrated in the hole. And a horizontal table structure in which the horizontal plate can be balanced with the installation surface of the baking furnace by adjusting the length of the balance adjustment screw protruding from the horizontal plate. It is characterized by the following. 2: At least one or more horizontal tables having the same size as or smaller than the horizontal table and having three legs whose lengths are similarly adjustable are stacked on the horizontal table.

The method of assembling a semiconductor device according to the present invention includes the steps of: (3) placing a horizontal table on a shelf of a baking furnace used for thermally curing the liquid resin; In the step of adjusting the length of the legs so that the horizontal table is horizontal, and in the step of obtaining the horizontal level of the horizontal table, place a level on the horizontal table and watch three bubbles while watching the air bubbles in the level. Adjusting the length of the legs, and placing a baking tray on which a semi-finished product coated with a liquid resin is mounted on the horizontal base on which the horizontal is obtained. In the step of heating and curing the product, the step of placing the horizontal table on a baking furnace and taking a level, thereby maintaining the level of the baking tray on which the semi-product mounted on the horizontal table is mounted, It is characterized by. 4: in the step of heating and curing the semi-finished product to which the liquid resin has been applied, the step of placing the same or a small-sized horizontal table described in the above-mentioned claim 2 on the horizontal table which is horizontal; A step of adjusting and leveling the three legs, the length of which can be adjusted, on the horizontal platform, the leveling process using a level, and the leveling process. A step of repeating at least one or more times, and a step of placing a baking tray on which a semi-finished product coated with a liquid resin is mounted on a horizontal table on which the uppermost surface is horizontal, wherein at least two or more horizontal tables are mounted. It is characterized by keeping the level of the baking tray on the top surface sufficiently by stacking while keeping the level.

[0011]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

<Description of Configuration> FIGS. 7 and 8 show a first embodiment of the present invention. FIG. 7 is a developed view of the horizontal base of the present invention as viewed from above and from the side. FIG. 8 is a diagram showing an embodiment in which the horizontal base of the present invention is used. As shown in FIG. 7, the thickness is 10 mm to 300 mm, the flatness is 0.05 mm to 1.00 mm, and the area is 0.5 mx 0.5 mm to 1 mx 1.
There are provided three screw holes penetrating the opposite sides of the horizontal plate 35 of m. The positions of these three screw holes are provided two on one side and one on the other side, and are provided 100 mm to 30 mm from the outer end of the horizontal plate 35. Screw the screw of the optimal size into this screw hole. This screw becomes the balance adjusting screw 34.
The balance adjusting screw 34 has a structure that can be inserted into the screw hole about half as long.

Next, the method of use will be described with reference to FIG. Balance adjustment leg 3 on the bottom of bake oven 36
9 is adjusted to obtain the degree of equilibrium of the entire baking furnace 36. The door 41 is opened and the level table 42 is placed on the shelf 40. A level is placed at the center of the level table 42, and three level adjustment screws 38 are turned while watching the bubbles of the level to turn the level table 42 into the baking furnace 36. Adjust so that it is balanced with the installation surface. Level 42
And the adjustment is repeated in both the vertical and horizontal directions. The baking tray 37 is placed on a horizontal table 42 placed on all the shelves 40 to be used. The semi-finished product of the semiconductor device to which the liquid sealing resin is applied is placed on the baking tray 37. Thereafter, the door 41 is closed and the resin is cured with desired heat.

<Description of Operation> FIG. 9 is a diagram showing the operation of the first embodiment of the present invention. The operation of the first embodiment of the present invention will be described with reference to FIG. The shelf 46 has an inclination B48 with respect to the bake furnace installation surface 47. A horizontal plate (large) 45 on which three balance adjustment screws (large) 44 are provided.
Put on. The three balance adjustment screws (large) 44 and the horizontal plate (large) 45 are collectively referred to as a horizontal table. The horizontal plate 45 has a baking furnace installation surface 47 and an inclination A43. By turning the heads of the three balance adjustment screws (large) 44 with respect to the inclination A43 and changing the lengths of the screws protruding from the back side of the horizontal plate (large) 45, the horizontal plate surface and the baking furnace installation surface are changed. 47 can be balanced. In the conventional method, the resin surface is inclined to cure the sealing resin with the inclination B48.
The horizontal base of the present invention is 500 mm × 500 mm and is approximately 0.1 mm.
The inclination of the sealing surface of the semiconductor device package of 45 mm □ or less can be suppressed to about 50 μm or less.

<Second Embodiment of the Invention> Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 10 is a diagram of the second embodiment viewed from above and from the side. This embodiment is characterized in that at least two or more horizontal bases having the structure shown in the first embodiment of the present invention are stacked. Thickness 10 mm to 30 mm, flatness 0.05 mm to 1.00 mm, area 0.5 mx 0.5 mm.
Three threaded holes are provided on opposite sides of a horizontal plate of 5 mm to 1 m x 1 m. The positions of the three screw holes are two on one side and one on the other facing side. Each screw hole is provided 100 mm to 300 mm from the outer end of the horizontal plate. Screw the screw of the optimal size into this screw hole. This screw becomes the balance adjustment screw. By adjusting the balance adjusting screw, the length of the screw protruding from the horizontal plate is adjusted to obtain the balance between the horizontal plate and the baking furnace installation surface. As shown in FIG. 10, a horizontal table (small) 49 with a balance adjustment screw shown below is placed on a horizontal table (large) 50 with a balance adjustment screw. The structure of the horizontal base (small) 49 with the balance adjustment screw is 10 mm to 20 m in thickness.
m, flatness 0.05 to 1.00 mm, area 0.1
Three screw holes penetrating the opposing sides of a horizontal plate of mx 0.1 mm to 1 mx 1 m are provided, and a screw having an optimum size is screwed into these three screw holes. The three screw holes are provided at two locations on one side and one on the other facing side, and have a structure provided 100 to 300 mm from the outer edge of the horizontal plate, and protrude from the horizontal plate. By adjusting the screw length, the structure can be balanced to the installation surface.

The effect and operation of the second embodiment will be described with reference to FIG. Tilt C with respect to bake furnace installation surface 56
At 57, a shelf 55 is placed. On the shelf 55, a horizontal base (large) with a balance adjustment screw composed of a horizontal plate (large) 54 and a balance adjustment screw (large) 53 is placed, and the bake is adjusted by adjusting the balance adjustment screw (large) 53. Equilibrate with the furnace installation surface 56. However, since a level is placed at the center and the horizontal level is maintained, the horizontal level plate (large) 54 has a certain inclination. When it is about 0.5 mm × 0.5 mm, the variation of the sealing surface in the 45 mm SQ. Area on the horizontal plate 54 becomes about 0.1 mm. In such a case, the local inclination can be further reduced by placing the horizontal table with the balance adjusting screw (small) on the horizontal table with the large balance adjusting screw (large) as in the second embodiment.

[0017]

The first effect is that the surface of the package for a semiconductor device and the surface of the sealing resin are kept horizontal with respect to the semiconductor device requiring a sealing step with a liquid sealing resin, and the resin is shifted in a direction in which the resin is present. The thickness of the resin partially increases, so that the distance between the tip of the external terminal and the resin surface, that is, the standoff does not satisfy the design value and the standard value, and the yield rate of manufacturing non-defective products can be increased.

The second effect is that the above-mentioned adjustment is performed in each step of enclosing the liquid resin, whereby the aging of the baking furnace, the deformation and inclination of the shelf are confirmed in advance, and the influence thereof is reduced. Can be enclosed without receiving.

The third effect is that if the standoffs do not satisfy the standard and design values due to the aging of the baking oven or the shelf, it is necessary to replace or repair parts of the shelf or the like. The body had to be renewed. This required a lot of expense and days. However, by using the horizontal base of the present invention, the influence of aging can be absorbed by the horizontal base, so that the durability can be improved.

[Brief description of the drawings]

FIG. 1 shows a baking furnace used to cure a liquid sealing resin.

FIG. 2 shows an embodiment of the prior art.

FIG. 3 is a diagram illustrating a problem that occurs in the related art.

FIG. 4 is a diagram illustrating a problem that occurs in the related art.

FIG. 5 shows a conventional technique for sealing using a liquid sealing resin;
3 is a cross-sectional structure of a manufactured semiconductor device, showing a cross-sectional structure of a non-defective product.

FIG. 6 shows a conventional technique for sealing using a liquid sealing resin;
4 is a cross-sectional structure of a manufactured semiconductor device, showing a cross-sectional structure of a defective product.

FIG. 7 is a developed view of a jig / tool structure for assembling and manufacturing a semiconductor device according to the present invention.

FIG. 8 shows a method of using the jig for manufacturing and assembling a semiconductor device according to the present invention.

FIG. 9 is a structural view of a jig / tool for assembling and manufacturing a semiconductor device, illustrating the operation and effect of the present invention.

FIG. 10 is a view of a jig / tool for assembling and manufacturing a semiconductor device according to a second embodiment of the present invention;

FIG. 11 is a structural view of a jig / tool for assembling and manufacturing a semiconductor device, illustrating the operation and effect of the second embodiment of the present invention.

[Explanation of symbols]

 1 Bake oven 2, 6, 12, 15, 40, 46, 55 Shelf 3, 9, 41 Door 4, 8, 39 Balance adjustment leg 5, 36 Bake oven 7, 11, 14, 37 Bake tray 10, 13 Bake sample (semiconductor device) 16, 25 Solder ball 17, 26 Resin dam 18, 27 Standoff 19, 28 Resin encapsulated 20, 29 Resin height 21, 30 Semiconductor device package 22, 31, Mounting material 23, 32 Semiconductor chip 24, 33 Bonding wire 34,38 Balance adjusting screw 35 Horizontal plate 42 Horizontal table 43 Tilt A 44,53 Balance adjusting screw (Large) 45 Horizontal plate (Large) 47 Bake furnace installation surface 48 Tilt B 49 Water with balance adjusting screw Flat table (small) 50 Horizontal table with balance adjustment screw (large) 51 Balance adjustment screw (small) 52 Horizontal plate (small) 54 Horizontal plate (large) 56 Click furnace installation surface 57 slope C

Claims (4)

[Claims] 1. A jig for assembling and manufacturing a semiconductor device used in a sealing process using a liquid resin of a semiconductor device, wherein the sealing resin is applied to a semi-finished product on which a semiconductor chip is mounted, and is applied in a baking furnace. A structure in which a through hole having three threads is provided in a thick horizontal plate that is less deformed by heat when the sealing resin is thermally cured; a structure in which three balance adjustment screws are inserted into the holes; Characterized in that the horizontal plate is provided with a horizontal table structure capable of adjusting the balance with the installation surface of the baking furnace by adjusting the length of the balance adjusting screw projecting from the horizontal plate. Jig and tool structure. 2. The apparatus according to claim 1, wherein at least one horizontal base having three legs, which is the same size as or smaller than the horizontal base and whose length is also adjustable, is overlapped on the horizontal base. 2. The jig and tool structure for assembling and manufacturing a semiconductor device according to 1. 3. A step of placing each of the horizontal tables on a shelf of a baking furnace used for thermally curing the liquid resin, and adjusting the lengths of three legs whose length of the horizontal table is adjustable,
Placing the level on the level in the step of making the level horizontal, and adjusting the length of the three legs while watching the bubbles in the level in the step of obtaining the level of the level. And a step of placing a baking tray on which a semi-finished product coated with a liquid resin is mounted on the horizontal table where the horizontal is obtained, wherein the semi-finished product coated with the liquid resin is heated and cured. Placing the horizontal table on a bake oven and leveling, thereby maintaining the level of the baking tray on which the semi-finished product mounted on the horizontal table is mounted. Method. 4. The step of heating and curing the semi-finished product to which the liquid resin has been applied according to claim 3, wherein the step of placing a horizontal table of the same size or a small size as the horizontal table on the horizontal table that is horizontal. A step of adjusting the three legs, the length of which can be adjusted on the horizontal table, and taking the level, using a level to take the level; and taking the level. A step of repeating the step at least once or more, and a step of placing a baking tray on which a semi-finished product coated with a liquid resin is mounted on a horizontal table on which the uppermost surface is horizontal. 4. The semiconductor device assembling method according to claim 3, wherein the baking tray on the uppermost surface is kept sufficiently horizontal by stacking the flat bases while keeping the horizontal.