JP2000031174A - Manufacturing method of semiconductor device, squeegee device used therefor and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of wire slippings when sealing printing is performed on a wiring substrate, so as to prevent the generation of recessed parts on the surface of the material to be sealed by having sealing material in uniform thickness. SOLUTION: When a sealing printing operation is performed, first printing is performed at a low speed for a squeegee 5 at 0.1 mm/sec to 70 mm/sec, and final printing is performed at a high squeegee speed of 10 mm/sec to 300 mm/sec in this manufacturing method. [However, (final speed/first speed is in the range of 1.2 to 3,000)]. The squeegee in this squeegee device used for the manufacture of this semiconductor device is maintained in a state in which the angle to the mask 3 of the tip part of the squeegee is inclined is such a manner that the upper part of the squeegee becomes the front, and whenever the moving direction of the squeegee changes, the inclination of the squeegee is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a semiconductor device obtained by encapsulating a semiconductor element in a wiring board, a method of manufacturing the same, and a squeegee device used in the manufacture thereof.

[0002]

2. Description of the Related Art A semiconductor device in which a semiconductor element is mounted on a wiring board has a semiconductor element mounted on the wiring board, and the semiconductor element is electrically connected to the wiring board by bonding wires, or a bump provided on the semiconductor element. The semiconductor device is manufactured by electrically connecting the semiconductor device to a wiring board by using the method described above, and then sealing the semiconductor device with a sealing material.

[0003] In this sealing, instead of a coating and sealing method using a dispenser which requires a sealing material having high thixotropy which causes a cost increase, a squeegee which can use a usual sealing material is used. A method of printing and sealing is employed. That is, as shown in FIG. 7A, the semiconductor element 2 is mounted on the wiring board 1 and the semiconductor element 2 is electrically connected to a circuit (not shown) of the wiring board 1 by a bonding wire W or the like. An opening 3 corresponding to the mounting position of the semiconductor element 2 on the wiring board 1
A printing mask 3 ′ provided with 1 ′ is superimposed on the wiring substrate 1 so that the semiconductor element 2 is located inside the opening 31 ′, and then a liquid sealing is applied on the mask 3 ′ in advance. By supplying the material 4 and printing the sealing material 4 with a squeegee 5, the sealing material 4 is pattern-printed on the surface of the wiring board 1 through the opening 31 ′ of the mask. FIG. 7B shows a semiconductor device obtained by removing the mask 3 ′ from the wiring board 1.

In a method of printing and sealing using a squeegee,
Since the sealing material is mechanically pushed with a stronger force than the method of sealing with a dispenser, the wire of the semiconductor element falls down due to the flow of the sealing material. May occur). In the method of printing with a squeegee, the thickness of the sealing material imprinted on the opening of the mask is further increased because the sealing material moves in accordance with the squeegee.
It tends to be relatively thin on the inlet side and relatively thick on the outlet side. This non-uniform thickness causes a shape failure in sealing semiconductor packages such as IC cards and cavity-down BGAs. The uniformity of the thickness of the sealing material is a very important evaluation item in these packages, and if the thickness of the sealing material becomes uneven, the situation that the IC card cannot be assembled and the BGA cannot be bonded to the board Invite.

[0005] When the sealing printing is performed under atmospheric pressure, air is entrapped in the liquid sealing material, air bubbles are left in the sealing portion, and a problem of void defect is likely to occur. Although voids can be removed by defoaming under reduced pressure after the encapsulation printing, there is a problem that bubbles are left on the surface and the surface of the encapsulant cannot be smoothed. In order to solve this problem, the present applicant has previously developed a method of performing sealing resin printing with a squeegee under reduced pressure (see Japanese Patent Application No. 9-194470-9-194472). According to this method, surface smoothness was achieved, but the phenomenon that the surface of the sealed object was depressed in the process of returning the atmosphere to the atmospheric pressure after the sealing printing occurred. This is because, when the opening is filled with the sealing material under reduced pressure, an unfilled portion (a gap in a reduced pressure state) remains under the wire in the opening or at a corner of the chip, and the sealing material is placed on the unfilled portion. Is likely to be covered, but when the atmosphere is returned to atmospheric pressure, the sealing material covering the unfilled part falls into the unfilled part (vacuum in a decompressed state) due to atmospheric pressure, and its surface is It appears as a dent.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce the thickness of the sealing material by preventing the wire from flowing when the semiconductor element is sealed and printed with the sealing material under reduced pressure using a squeegee. An object of the present invention is to provide a semiconductor device which is uniform and has no dent on the surface of a sealing material, a method of manufacturing the same, and a squeegee device used for the manufacture thereof.

[0007]

In order to solve the above-mentioned problems, a method of manufacturing a semiconductor device according to the present invention comprises a step of electrically connecting a semiconductor element to a wiring board and mounting the semiconductor element on a wiring board. A mask having an opening is superimposed on a wiring board so that a semiconductor element is positioned inside the opening, and a sealing material supplied on the mask is reciprocated by a squeegee under reduced pressure conditions. By imprinting, in the method of manufacturing a semiconductor device comprising a step of sealing printing on a wiring board, when performing the sealing printing,
Imprint for the first time, the squeegee speed is 0.1mm / sec
The final printing is performed with the squeegee speed set to a high speed of 10 mm / sec to 300 mm / sec. [However, (the speed of the last round / the speed of the first round) = 1.2 to 3000].

In order to solve the above problems, a squeegee device for manufacturing a semiconductor device according to the present invention is a squeegee device used in the method of manufacturing a semiconductor device. Is held in such a state that the upper part is inclined forward so that the inclination of the squeegee is changed each time the moving direction changes.

In order to solve the above-mentioned problems, in a semiconductor device according to the present invention, a semiconductor element electrically connected to and mounted on a wiring board is mounted on the wiring board by a sealing printing method in the method of manufacturing a semiconductor device. It is sealed.

[0010]

FIG. 1 shows an embodiment of a method of manufacturing a semiconductor device according to the present invention in the order of steps. As shown in FIG. 1, a printing mask 3 in which a semiconductor element 2 is mounted on a wiring board 1 and a plurality of openings 31 are provided in accordance with the mounting position of the semiconductor element 2 on the wiring board 1.
Are superimposed on the wiring board 1 such that the semiconductor element 2 is positioned inside each of the openings 31..., And the sealing material 4 supplied on the mask 3 is printed with a squeegee 5 so that the mask 3 The sealing material 4 is printed on the surface of the wiring substrate 1 through the openings 31.

In this case, after the mounting of the semiconductor element 2, the setting of the mask 3 and the supply of the sealing material 4, the wiring substrate 1 and the vacuum chamber 61 in FIG.
Printing of the sealing material 4 by the squeegee 5 is performed under reduced pressure. At the time of imprinting, air may be entrapped in the sealing material and air bubbles (voids) may remain in the sealing portion. However, if the imprinting is performed under reduced pressure as described above, the sealing material It is difficult for air to be trapped.

Referring to FIG. 5, a vacuum chamber 61 is provided.
The passage 62 opened to the inside is connected to a vacuum pump (not shown) for reducing the pressure inside the chamber 61. The wiring substrate 1 is placed on the receiving tray 63 outside the vacuum chamber 61, and the mask 3 is overlaid thereon. The sealing material 4 is supplied to the mask 3 from the syringe 64. The sealing material 4 preferably has an inorganic filler content of 40 to 90% by weight, a viscosity of 100 to 5000 ps (25 ° C.), and a thixotropy index of 1.0 to 4.5 (25 ° C.).

Thereafter, the receiving tray 63 enters the vacuum chamber 61, and the above-described sealing operation is performed. The chamber 61 swings up and down by the action of the rotating bar 65, rises when the receiving tray 63 enters, and descends when the receiving tray 63 reaches the sealing work position on the worktable 66, and moves the receiving tray 63. cover. The squeegee 5 performs the printing operation by the function of the air cylinder 67. When the sealing operation is performed in a heated atmosphere of, for example, 25 to 40 ° C., the viscosity of the sealing material 4 is reduced, so that bubbles are easily released, and the stringing phenomenon occurs when the mask 3 is separated from the wiring substrate 1. It is hard to get up. In addition,
When the heating atmosphere reaches the syringe 64, the pot life of the sealing material 4 is shortened. Therefore, an electric heater (not shown) is provided in a reaction body mounting portion of the receiving tray 63, and only necessary portions, for example, 40 to 100, are provided. It is preferred to heat to about ° C.

In the method of the present invention, sealed printing is performed under reduced pressure. In this case, the degree of pressure reduction at the time of the first printing is, for example, 3.9 kPa (30 Torr) or less, preferably 0.6 kPa (30 Torr) or less.
5 kPa (5 Torr) or less, more preferably 0.13 kP
a (1 Torr) or less. 3.9k at first printing
When the pressure is closer to the atmospheric pressure than Pa, voids due to entrainment of air may easily occur.

In order to reliably fill the unfilled portion with the sealing material in the sealing printing under reduced pressure, the second and subsequent times are adjusted so that the degree of reduced pressure is less than that of the previous time (or It is preferable to gradually reduce the degree of decompression as the number of times of printing is repeated. Of course, in some cases, the previous time and the current time may be the same, but it is preferable to gradually reduce the degree of pressure reduction (to further increase the atmospheric pressure) as an overall tendency. With this configuration, for example, the degree of decompression during the second printing is lower than the degree of decompression during the first printing (= the degree of decompression is reduced). The pressing force based on the pressure difference is applied to the surface of the sealing material, and the filling is sufficiently performed. Specifically, the sealing printing is performed by moving the squeegee at least once in the atmosphere of each reduced pressure from the atmosphere of high reduced pressure to the atmosphere of low reduced pressure, and the filling of the sealing material is advanced.

The semiconductor device 2 used in the present invention has 20
Electrical conduction with the wiring substrate 1 is performed by using a large number of very weak bonding wires W made of gold, Al or the like having a size of about 1 micron. When the liquid sealing material 4 is sealed and printed on such a semiconductor element 2 using a squeegee 5, the wire W is pushed down in the moving direction of the sealing material 4 by the flow force of the sealing material 4. In the method of the present invention, the flow pressure of the sealing material 4 applied to the wire W is reduced by setting the speed of the squeegee 5 at the time of the first printing as low as possible. At this time, if the squeegee speed is too low, the problem of productivity deterioration occurs. Therefore, the initial squeegee speed is 0.1 mm / sec to 70 mm.
mm / sec, preferably 1.0 mm / sec to 30 mm / sec. If it exceeds 70 mm / sec, wire flow will occur. If the speed is lower than 0.1 mm / sec, the productivity will deteriorate.

In order to prevent air entrapment (void generation) during printing, sealed printing is performed under reduced pressure. However, even under reduced pressure, some air is present. However, in the present invention, since the initial squeegee speed is lower than the final speed speed, this sparse air entrainment does not occur, resulting in a void dress. Squeezing at high speed when printing under reduced pressure, such as under the wire or the corner of the chip
In areas where it is difficult to fill the sealing material, poor filling of the sealing material occurs and unfilled parts are likely to occur.However, if the squeezing speed is low, the sealing material flows slowly, so even in areas where filling is difficult The sealing material is sufficiently filled. For this reason, it is possible to reduce the depression on the surface of the sealed object when the pressure is returned to the atmospheric pressure later.

If the initial squeegee speed is low, it is effective in reducing entrapment voids and preventing wire flow. Conversely, when performed at low speed, the sealing material 4 is pulled together with the squeegee 5, As shown in FIG.
The thickness of the sealing material tends to be small on the entrance side of the opening 31 of the mask 3 and thick on the exit side of the opening 31. This is presumably because when the squeegee speed is low, the frictional force between the squeegee 5 and the sealing material 4 (= the force pulling the sealing material) increases.

After the previous squeezing, it is preferable to stop the squeegee for 5 seconds to 15 minutes before changing the degree of pressure reduction. During this stop, as shown in FIG.
This is because bubbles 41 entrained in the sealing material 4 in the opening 31 float on the surface of the sealing material 4. If the stop time is shorter than 5 seconds, the bubbles may not be completely removed, and if the stop time exceeds 15 minutes, the productivity may be deteriorated.

If the degree of pressure reduction in the vacuum chamber 61 is close to the atmospheric pressure after the above-described stop time after performing the sealing printing, the surface of the sealing layer may be roughened. Therefore, at this time, after the pressure in the chamber 61 is adjusted to reduce the pressure, the squeegee 5 is driven again,
Perform check printing (this may be the last round).

The surface of the filled sealing material 4 may have irregularities as shown in FIG. 1C. In order to reduce the unevenness, it is preferable to increase the squeegee speed at the time of final printing. In the final round, as shown in FIG. 1D, the wire W is already covered with the sealing material 4, so that even if the squeegee speed is increased, no force is applied so that the wire W falls. The final squeegee speed is 10mm / sec
~ 300mm / sec, preferably 100 ~ 200mm / sec
It is. If the squeegee speed is within this range, the squeegee speed is high.
And the sealing material 4 becomes squeegee 5
As a result, the surface of the sealing material 4 becomes flat as shown in FIG. 1E, and the thickness of the sealing material becomes uniform. However, the last squeegee
If the speed is lower than 10 mm / sec, the sealing material 4 is pulled by the squeegee 5, and the thickness of the sealing material in the opening 31 becomes uneven. Further, when the final squeegee speed is faster than 300 mm / sec, the force applied to the wire W increases, and the wire W may fall.

As described above, the final squeegee speed is set to be higher than the initial squeegee speed. When this value is expressed as a numerical value, (final speed / initial speed) = 1.2 to 3000. is there. This ratio is 1.
When it is lower than 0, the first time is high speed and the last time is low speed, so that the wire flows, the void is mixed, or the pulling force of the sealing material 4 becomes strong for the above-mentioned reason. In the case of 1.0 ≦ the ratio <1.2, the effect of increasing the speed at which resin pulling in the final round can be reduced is smaller than in the case of 1.2 or more, and it is difficult to make the sealing thickness uniform. The total time of the encapsulation printing is also long, and the productivity is poor.
If the ratio exceeds 3000, there is a problem that the first printing is too slow and the printing time is too long and the productivity is deteriorated, or the final printing is too fast and the wire falls.

As described above, it is preferable that the degree of decompression is reduced in the second and subsequent times as compared with the immediately preceding time. However, even when the degree of decompression is reduced, the degree of decompression in the final printing is reduced. Is preferably maintained at 50 kPa (about 400 Torr) or less. This is to prevent air entrainment from occurring. In the above, the second printing is the final printing, but the third and subsequent printings may be the final printing.

After the final printing sealing, the pressure is returned to the atmospheric pressure, air is introduced, and the mask 3 is separated from the wiring substrate 1.
It is effective that the material of the squeegee 5 is hard for flattening the surface of the sealing layer. When a soft (hardness: 20 to 30 °) squeegee 5a such as urethane rubber is used, as shown in FIG. 2A, the center of the squeegee 5a bends in a convex shape, so that the scraping amount of the sealing material 4 is reduced. At the central portion of the opening 31, the thickness is larger than that at the peripheral portion, and the thickness of the sealing layer becomes uneven. On the other hand, the hard squeegee 5b
As shown in FIG. 2 (b), since the central portion does not bend, the flatness of the sealing material 4 is improved and the thickness becomes uniform. The material of the squeegee 5 is not particularly limited as long as it is hard. For example, metals such as iron and aluminum and alloys thereof; fluoroplastics, polycarbonate, hard plastics such as urethane having a hardness of 70 ° or more; or a composite of metal and plastic Things. A plastic coated metal surface is also effective. As shown in FIG. 2 (c), the degree of rigidity is such that the tip of the squeegee becomes flat without bending when the squeegee is moving through the opening of the mask, for example, 0.1 kgf / cm or more. It is preferable to have a strength that does not deform even when a load is applied.

As shown in FIG. 3, the shape of the tip of the squeegee 5 is different from the mask 3 of the surface 51 (facing in the traveling direction) with respect to the traveling direction of the squeegee 5 (indicated by a right-pointing arrow in the figure). The angle (α) is an acute angle (90 °> α), and the angle (β) of the opposite surface 52 to the mask 3 with respect to the traveling direction is an obtuse angle (90 °).
° <β). If α is an acute angle, the sealing material can be extruded downward while rotating the sealing material in front of the surface, so that the sealing material can be uniformly spread. If α is an obtuse angle, no downward pushing force is applied, and the sealing material cannot be spread uniformly. Further, if β is an obtuse angle, it is possible to prevent the sealing material from warping up to the squeegee rear surface (opposite surface 52) (to adhere to the squeegee rear surface and the sealing material due to frictional resistance).
If β is an acute angle, since the sealing material warps to the back of the squeegee, a streak-like appearance can be formed on the surface of the printed sealing material, and a uniform sealed product cannot be obtained.

The shape of the portion of the squeegee that is in contact with the mask can be a line as shown in FIG. 3A if the angles α and β can be realized (α is an acute angle and β is an obtuse angle). Contact or surface contact as shown in FIG. 3B may be used. As shown in FIG. 4A, the squeegee tip fixing jig 55 and the printing apparatus main body 56 are used to fix the squeegee tip 51 at an angle where the squeegee surfaces 51 and 52 are in contact with the mask 3, as shown in FIG. It is necessary to have a structure having a flexible portion 57 between them. The mechanism of the flexible portion 57 needs to have high mechanical strength in the Z direction enough to withstand the printing pressure applied to the squeegee 5. However, it is necessary to have a mechanism capable of changing the angle. This mechanism makes it possible to always achieve the optimum squeegee angle even when the squeegee 5 reciprocates. Instead of the flexible portion 57 shown in FIG. 4, (b) of FIG.
As shown in FIG.
6 may be supported.

[0027]

EXAMPLES Examples of the present invention and comparative examples outside the scope of the present invention will be shown below, but the present invention is not limited to the following examples. (Examples 1 to 9 and Comparative Examples 1 to 8) As the sealing material 4, "Panasealer CV5420" manufactured by Matsushita Electric Works, Ltd.
(Viscosity 700 ps (measured at 25 ° C. with a B-type viscometer) and a thixotropic index of 1.2 (measured at 25 ° C. with a B-type viscometer)).

The mask 3 is made of stainless steel SUS304,
1.0mm thick opening 20x20mm 3
The one with 1 was used. A semiconductor element 2 having a size of 12 × 12 × 0.3 mm mounted on a glass-epoxy substrate as the wiring board 1 with 44 gold wires (30 μm diameter) was sealed. At this time, the mask 3 having the opening 31 corresponding to the mounting position of the semiconductor element 2 is overlaid on the wiring board 1 so that the semiconductor element 2 is positioned inside the opening 31, and the sealing supplied on the mask 3 is performed. The stopper material 4 was printed on the opening 31 by reciprocating the squeegee 5. The temperature of the substrate and the resin during printing was 30 ° C. ± 0.5 ° C.

The squeegee was one reciprocation of the first time and the last time, and the speed, the degree of pressure reduction, the squeegee stop time, and the material of the squeegee were changed as shown in Table 1. The shape of the squeegee was a knife shape as shown in FIG. 3A (the tip is a line contact type), and α = 30 ° and β = 120 ° were used. In each of the first and last squeegees, the angle of the tip of the squeegee with respect to the mask is inclined such that the upper part is forward (α = 30 °, β = 120).
°), the squeegee was held, and the squeegee tilt was changed between the first time and the last time.

After the sealing material 4 is printed on the opening 31 and the mask 3 is removed, the resin is cured at 100 ° C., 1
h + 150 ° C. for 3 hours to obtain a semiconductor device. As shown in FIG. 6, the thickness of the resin was determined as follows. As shown in FIG. 6, the sealing material obtained by printing the opening of the metal mask 3 having a thickness of 1.0 mm with a squeegee of the material shown in Table 1 under the conditions shown in Table 1 was used. The thickness a of the sealing material 4 at the center of the range, the thickness b of the thickest portion of the sealing material 4, and ba = t (comparison with the cured product) are obtained.
Are shown in Table 1. The unit is μm. In general,
It is said that t ≦ 50 μm is practical, so that t ≦
Those having a size of 50 μm are good.

The presence / absence of voids was determined by cutting the resin cured product and visually confirming the presence / absence of voids (30 times magnification), and evaluated according to the following criteria. ：: No void, Δ: Almost none, ×: Many voids. The presence / absence of wire flow was confirmed by soft X-rays of the cured resin (using a device manufactured by Hitex Co., Ltd.) and evaluated according to the following criteria.

：: no wire flow, Δ: almost no, ×: wire flow.

[0033]

[Table 1]

As shown in Table 1, in the semiconductor device obtained in the example, the difference in resin thickness is small, the number of voids is small, and the wire does not flow much. On the other hand, in the case of the comparative example, the wire flow occurred, the resin thickness difference was large, or voids were generated.

[0035]

According to the method of manufacturing a semiconductor device according to the present invention, the initial sealing printing of a plurality of sealing printings is performed by setting the squeegee speed to a low speed of 0.1 mm / sec to 70 mm / sec. The final round of sealing printing is performed with the squeegee speed set to a high speed of 10 mm / sec to 300 mm / sec. (However, (last speed / first speed) =
1.2 to 3000. Accordingly, since the semiconductor element is sealed with the sealing material, the flow of the wire does not occur, the sealing material has a uniform thickness, and the surface of the sealing object can be sealed without any dent.

The degree of pressure reduction at the time of printing is 3.
The pressure is 9 kPa or less, and the pressure is adjusted based on the pressure difference on the surface of the sealing material at the time of changing the degree of pressure reduction by adjusting the degree of pressure reduction after the second time so as to be less than that of the previous time. Dents are less likely to occur on the surface of the sealing material. Before changing the degree of decompression, stop the squeegee for at least 5 seconds and within 15 minutes, and then change the degree of decompression, so that air bubbles rise to the upper surface of the sealing material, and unfilled portions are less likely to remain. Become.

According to the squeegee apparatus for manufacturing a semiconductor device according to the present invention, the squeegee is inclined at least at the time of movement so that the tip of the squeegee with respect to the mask is located such that the upper part is forward. Since the inclination of the squeegee is changed, it is easy to take an angle that does not easily cause a streak-like squeegee in accordance with the direction of the mask. The same squeegee can be used for reciprocating movement without providing two squeegees, and the cost can be reduced.

If at least the tip of the squeegee is made of a hard material that does not deform when the tip moves over the opening during printing, the flatness of the sealing material is improved, and the thickness of the squeegee is increased. Becomes more uniform. At least at the end of the squeegee at the time of movement, the surface facing the traveling direction has an acute angle (90 °>), and the surface opposite to the traveling direction has an obtuse angle (90 ° <). In addition, it is difficult to form streaks on the upper surface of the sealing material, and a more uniform sealing is obtained.

[Brief description of the drawings]

FIG. 1 is a partial sectional view illustrating an embodiment of a manufacturing method according to the present invention in the order of steps.

FIGS. 2 (a) and 2 (b) are partial side sectional views showing differences depending on the material of a squeegee used in the present invention, and a plan view (c) at this time.

FIGS. 3A and 3B are partial side sectional views showing an angle of a squeegee with respect to a mask.

FIGS. 4A and 4B are enlarged views showing two embodiments of a squeegee device according to the present invention.

FIG. 5 is a side view showing one embodiment of a method for manufacturing a semiconductor device according to the present invention.

FIG. 6 is a side sectional view showing a method for examining a difference in resin thickness in Examples.

FIGS. 7A and 7B are a partial side sectional view showing a state of use of a conventional mask, and a partial side sectional view of a sealed semiconductor device obtained by using the mask.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wiring board 2 Semiconductor element 5 Squeegee 3 Mask 31 Opening

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Kenji Kitamura 1048 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Works F-term (reference) 2C035 AA06 FD00 FD07 FD15 FD19 FD37 FF26 2H114 AB11 AB17 EA01 EA04 FA02 GA34 4D075 AC49 AC53 AC88 AC93 AC94 DC21 5F061 AA01 BA03 CA12 DE06

Claims (7)

[Claims] A semiconductor device is electrically connected and mounted on a wiring substrate, and a mask having an opening corresponding to a mounting position of the semiconductor device is arranged on a wiring board such that the semiconductor element is positioned inside the opening. A method of manufacturing a semiconductor device comprising a step of performing sealing printing on a wiring substrate by superimposing a sealing material supplied on the mask on a substrate by reciprocating a squeegee under reduced pressure conditions and printing the sealing material on the opening. During the encapsulation printing, the first printing is performed with the squeegee speed set to a low speed of 0.1 mm / sec to 70 mm / sec, and the last printing is performed with the squeegee speed set to 10 mm / sec.
Performing at a high speed of sec to 300 mm / sec [However, (final speed / initial speed) = 1.2 to 3000]
A method for manufacturing a semiconductor device. 2. The degree of pressure reduction during printing is 3.
2. The method of manufacturing a semiconductor device according to claim 1, wherein the pressure is adjusted to be 9 kPa or less, and to reduce the degree of pressure reduction in the second and subsequent rounds so as to be lower than in the immediately preceding round. 3. The squeegee is temporarily stopped for at least 5 seconds and up to 15 minutes before changing the degree of pressure reduction, and then the degree of pressure reduction is changed.
A method for manufacturing a semiconductor device according to claim 2. 4. A squeegee device for use in the method of manufacturing a semiconductor device according to claim 1, wherein the squeegee has an upper portion whose angle with respect to the mask at least at the time of movement. A squeegee device for manufacturing a semiconductor device, wherein the squeegee device is configured to be held in an inclined state such that the squeegee is moved forward, and the inclination of the squeegee is changed each time the moving direction changes. 5. The squeegee, at least at the time of movement, has an acute angle (90 °>) on a surface facing the advancing direction and an obtuse angle (90 ° <) on a surface opposite to the advancing direction. The squeegee device according to claim 4, wherein the squeegee device is configured as follows. 6. The squeegee apparatus according to claim 4, wherein the squeegee is made of a hard material whose at least the tip does not deform when the tip moves over the opening during printing. . 7. A semiconductor device, wherein a semiconductor element electrically connected to and mounted on a wiring board is sealed on the wiring board by the sealing printing method according to any one of claims 1 to 3. .