WO2019123518A1 - Semiconductor device, method for manufacturing semiconductor device, and adhesive - Google Patents

Abstract

Disclosed is a method for manufacturing a semiconductor device, the method including: a step for pressure-bonding a first member having a connecting portion and a second member having a connecting portion at a temperature lower than the melting point of the connecting portion of the first member and the melting point of the connecting portion of the second member by using a thermosetting adhesive to thereby obtain a temporarily pressure-bonded body in which the connecting portion of the first member and the connecting portion of the second member are disposed facing each other; a step for obtaining a pressure-bonded body by sandwiching the temporarily pressure-bonded body between a pair of the pressing members disposed facing each other and by pressurizing the same while heating to a temperature higher than the melting point of at least one among the connecting portion of the first member and the connecting portion of the second member; and a step for further heating the pressure-bonded body in a pressurized atmosphere. The first member is a semiconductor chip or a semiconductor wafer, and the second member is a wiring circuit board, a semiconductor chip or a semiconductor wafer.

Description

Semiconductor device, method of manufacturing semiconductor device, and adhesive

The present invention relates to a semiconductor device, a method of manufacturing a semiconductor device, and an adhesive.

Conventionally, when connecting a semiconductor chip and a substrate, a wire bonding method using metal thin wires such as gold wires has been widely applied.

In recent years, in order to meet the demand for high performance, high integration, high speed, etc., for semiconductor devices, conductive bumps called bumps are provided as connecting portions on a semiconductor chip or wiring circuit board, and semiconductor chips and wiring are connected by connecting the connecting portions. A flip chip connection method (FC connection method) for directly connecting a circuit board or another semiconductor chip is widely adopted. For example, a COB (Chip On Board) type connection method, which is a connection between a semiconductor chip and a printed circuit board, is an FC connection method. The FC connection method is widely used also in a CoC (Chip On Chip) connection method in which bumps or wires are provided as connection portions on a semiconductor chip and connected between semiconductor chips.

In the FC connection method, in general, connection portions such as solder, tin, gold, silver, copper and the like are often metal-joined from the viewpoint of connection reliability.

JP, 2008-294382, A

In the assembly of a semiconductor device of the FC connection type, generally, a semiconductor chip is first picked up by a collet from a diced semiconductor wafer and supplied to a pressing device. Next, the semiconductor chip is crimped to the printed circuit board or another semiconductor chip by a pressing device. During crimping, the temperature of the pressing device is increased so that the metal of one or both of these connections reaches a temperature above the melting point so that a metallurgical bond is formed. Thereafter, after the high temperature pressing device is cooled, the semiconductor chip is again supplied to the pressing device. A semiconductor adhesive may be supplied in advance on the semiconductor chip to be picked up by the collet, in which case the pressing device is heated from the high temperature at which the metal of the connection portion is melted to continuously manufacture the semiconductor device. It is necessary to cool the adhesive-supplied semiconductor chip to a low temperature that can be supplied.

Therefore, one pressing device temporarily crimps the semiconductor chip on the printed circuit board or another semiconductor chip at a relatively low temperature, and heats the obtained temporary crimped body at a high temperature using a pressing device different from the temporary crimping. However, it is not necessary to repeat heating and cooling of the pressing device by adopting a method of applying pressure and bonding the semiconductor chip to the printed circuit board or another semiconductor chip and obtaining a connected body electrically connected. It is expected that production efficiency will improve.

However, even such a method is not always sufficient in terms of production efficiency. When a large number of semiconductor devices are continuously manufactured, a large number of pressing devices are required, and there is a limit to improvement in production efficiency.

According to the study of the present inventors, the step of temporarily pressure-bonding the semiconductor chip and the substrate or another semiconductor chip at a relatively low temperature using the first pressing device, and the second step different from the first pressing device And a step of obtaining a pressure-bonded body by applying pressure while heating at a temperature equal to or higher than the melting point of the metal of the connection portion of the semiconductor chip or the substrate using the pressure device; and a step of further heating the pressure-bonded body in a heating furnace. By the method, the production efficiency can be further improved. However, in the case of manufacturing a semiconductor device with high density, thickness reduction, and miniaturization particularly by this method, there is a possibility that connection failure may occur or voids may remain in the adhesive. It became clear by the further examination of them. It is desirable that the voids be suppressed because the voids can be a source of reduced reliability.

Therefore, an object of one aspect of the present invention involves bonding a semiconductor chip or a semiconductor wafer having a connection portion to another member having a connection portion via an adhesive and electrically connecting the connection portions. Another object of the present invention is to provide a method of manufacturing a semiconductor device, which makes it possible to efficiently manufacture a large number of semiconductor devices while suppressing the generation of voids in an adhesive and ensuring an appropriate electrical connection.

One aspect of the present invention relates to a first member having a connection portion and a second member having a connection portion, the melting point of the connection portion of the first member and the second portion having a thermosetting adhesive. Obtaining a temporary pressure-bonded body in which the connection portion of the first member and the connection portion of the second member are disposed to be opposed by pressure bonding at a temperature lower than the melting point of the connection portion of the two members; By holding the temporary pressure-bonded body between a pair of opposed pressing members, the temporary pressure-bonded body is heated to a temperature equal to or higher than the melting point of at least one of the connection portion of the first member and the connection portion of the second member. A method of manufacturing a semiconductor device is provided, comprising the steps of obtaining a pressure-bonded body by pressing and heating the pressure-bonded body in a pressured atmosphere. The first member may be a semiconductor chip or a semiconductor wafer, and the second member may be a printed circuit board, a semiconductor chip or a semiconductor wafer.

Here, in the present specification, the step of obtaining a temporary press-bonded body by pressing the first member and the second member via the thermosetting adhesive may be referred to as "first pressing step". . The step of obtaining a crimped body by pressing the temporary crimped body while heating to a temperature equal to or higher than the melting point of at least one of the connecting portion of the first member and the connecting portion of the second member is referred to as "second crimping step". Sometimes. The step of further heating the crimped body in a pressurized atmosphere is sometimes referred to as the "third crimping step". A combination of these three pressure bonding processes can efficiently produce a large number of semiconductor devices while suppressing the generation of voids in the adhesive and ensuring an appropriate electrical connection.

Third pressure bonding step in which a thermosetting adhesive is partially cured in the second pressure bonding step to obtain a pressure bonded body by heating and pressing the temporary pressure bonded body, and the pressure bonded body is heated in a pressure atmosphere The thermosetting adhesive may be further cured. In this case, in the second pressure bonding step, the thermosetting adhesive may be cured until the curing reaction rate becomes 30% or less. In the third pressure bonding step, the thermosetting adhesive may be further cured until the curing reaction rate reaches 85% or more.

In the third pressure-bonding step of heating the pressure-bonded body in a pressurized atmosphere, the plurality of pressure-bonded bodies may be heated at one time. The heating temperature in the third pressure bonding step may be 130 ° C. or more and 300 ° C. or less.

The thermosetting adhesive may contain a thermosetting resin having a weight average molecular weight of less than 10000, a curing agent for the thermosetting resin, and a polymer component having a weight average molecular weight of 10000 or more.

Another aspect of the present invention relates to a thermosetting adhesive used in the method described above. The minimum melt viscosity of the adhesive may be 3000 Pa · s or less. The thermosetting adhesive may be in the form of a film.

A further aspect of the present invention comprises a first member having a connection, a second member having a connection, and an adhesive layer interposed therebetween, the connection of the first member And a connection portion of the second member are electrically connected by metal bonding. The adhesive layer may be a cured product of a thermosetting adhesive, and the minimum melt viscosity of the thermosetting adhesive may be 3000 Pa · s or less. The first member is a semiconductor chip or a semiconductor wafer, and the second member is a printed circuit board, a semiconductor chip or a semiconductor wafer.

One aspect of the present invention is a semiconductor device including bonding a semiconductor chip or a semiconductor wafer having a connection portion to another member having the connection portion via an adhesive and electrically connecting the connection portions. With respect to the method of manufacturing the semiconductor device, it is possible to efficiently manufacture a large number of semiconductor devices while suppressing the generation of voids in the adhesive and ensuring an appropriate electrical connection.

It is process drawing which shows one Embodiment of the process of crimp-bonding a 1st member and a 2nd member, and obtaining a temporary crimping | compression-bonding body. It is process drawing which shows one Embodiment of the process of heating and pressurizing a temporary press-fit body, and obtaining a press-fit body. It is a process chart showing an embodiment of a process of heating a crimped body under pressurization atmosphere. It is a schematic cross section which shows other one Embodiment of a semiconductor device. It is a schematic cross section which shows other one Embodiment of a semiconductor device. It is a schematic cross section which shows other one Embodiment of a semiconductor device. It is a schematic cross section which shows other one Embodiment of a semiconductor device.

Hereinafter, some embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

(Method of manufacturing semiconductor device)
FIG. 1, FIG. 2 and FIG. 3 are process drawings showing one embodiment of a method of manufacturing a semiconductor device. In the method according to the present embodiment, the melting point of the connection portion of the first member and the second member of the first member having the connection portion and the second member having the connection portion via the thermosetting adhesive. Obtaining a temporary pressure-bonded body in which the connection portion of the first member and the connection portion of the second member are disposed opposite to each other by pressure bonding at a temperature lower than the melting point of the connection portion of The temporary pressure-bonded body is interposed between a pair of opposing pressing members to heat the material while heating to a temperature equal to or higher than the melting point of at least one of the connection of the first member and the connection of the second member. A second pressure-bonding step of obtaining a pressure-bonded body by pressing, and a third pressure-bonding step of heating the pressure-bonded body under a pressure atmosphere are included.

FIG. 1 shows a first pressure-bonding step of obtaining a temporary pressure-bonded body 4 by pressure-bonding the semiconductor chip 1 (first member) and the printed circuit board 2 (second member). First, as shown in FIG. 1A, a semiconductor chip body 10 and a semiconductor chip 1 having a bump 30 as a connection portion, a substrate body 20, and a wired circuit board 2 having a wiring 16 as a connection portion Then, while arranging a thermosetting adhesive layer 40 between them, the laminate 3 is formed. The semiconductor chip 1 is formed by dicing of a semiconductor wafer, then picked up and transported to the wiring circuit board 2 and aligned so that the bumps 30 as the connection portions and the wirings 16 are disposed to face each other. The laminate 3 is formed on a stage 42 of a pressing device 43 having a pressure bonding head 41 and a stage 42 as a pair of opposing temporary pressure bonding pressing members. The bumps 30 are provided on the wiring 15 provided on the semiconductor chip body 10. The wires 16 of the printed circuit board 2 are provided at predetermined positions on the substrate body 20. Each of the bumps 30 and the interconnections 16 has a surface formed of a metal material.

The thermosetting adhesive layer 40 may be a layer formed by attaching a film adhesive prepared in advance to the printed circuit board 2. The film-like adhesive can be attached by a heat press, roll laminate, vacuum laminate or the like. The supply area and thickness of the adhesive layer are appropriately set in accordance with the size of the semiconductor chip 1 or the printed circuit board 2, the height of the connection portion, and the like. A film-like adhesive may be attached to the semiconductor chip 1. The film-like adhesive may be attached to the semiconductor wafer, and then the semiconductor wafer may be diced to separate the semiconductor wafer, thereby producing the semiconductor chip 1 to which the film-like adhesive is attached.

Subsequently, as shown in (b) of FIG. 1, the laminated body 3 is heated and pressed by being sandwiched between the stage 42 and the pressure bonding head 41 as a temporary pressure bonding pressing member, whereby the semiconductor chip 1 is The wiring circuit board 2 is temporarily pressure-bonded to obtain a temporary pressure-bonded body 4. In the case of the embodiment of FIG. 1, the pressure bonding head 41 is disposed on the semiconductor chip 1 side, and the stage 42 is disposed on the printed circuit board 2 side. A flip chip bonder or the like can be used as a temporary pressure bonding pressing device having a stage and a pressure bonding head.

When at least one of the stage 42 and the pressure bonding head 41 heats and presses the laminate 3 for temporary pressure bonding, the melting point of the bumps 30 as the connection portion of the semiconductor chip 1 and the connection portion of the printed circuit board 2 It is heated to a temperature lower than the melting point of the wiring 16. As used herein, “melting point of connection” means the melting point of the metal material forming the surface of the connection.

In the step of obtaining the temporary press-bonded body, the pressing member for temporary press-bonding is set to a low temperature so that heat is not transferred to the semiconductor chip or the like when picking up the semiconductor chip or the like as the first member. The temporary pressing member may be heated to a high temperature to a certain extent in order to enhance the fluidity of the adhesive layer to the extent that the rolled-in voids can be eliminated during heating and pressing of the laminate for temporary pressing. In order to shorten the cooling time, the difference between the temperature of the pressing member when picking up a semiconductor chip or the like and the temperature of the pressing member when heating and pressing the laminated body to obtain a temporary pressure-bonded body may be small. The temperature difference may be 100 ° C. or less, or 60 ° C. or less. This temperature difference may be constant. When the temperature difference is 100 ° C. or less or 60 ° C. or less, the time required for cooling the temporary pressure bonding pressing member can be shortened.

The temperature of the pressing member for temporary pressure bonding when heating and pressing the laminate to obtain the temporary pressure bonded body may be a temperature lower than the reaction start temperature of the adhesive layer. The reaction start temperature is obtained by using DSC (Perkin Elmer, DSC-Pyirs 1), and measuring the sample amount of adhesive 10 mg, heating rate 10 ° C./min, measurement atmosphere: under conditions of air or nitrogen. On-set temperature in the DSC thermogram.

From the above point of view, the temperature of the stage 42 and / or the pressure bonding head 41 when the laminate is heated and pressed to obtain a temporary pressure bonded body is such that the adhesive adheres to the printed circuit board or semiconductor wafer etc. It can be set to a temperature at which the curing reaction does not proceed. From this point of view, the temperature of the stage 42 and / or the pressure bonding head 41 when heating and pressing the laminate to obtain a temporary pressure-bonded body may be 140 ° C. or less, 110 ° C. or less, or 80 ° C. or less. It may be 25 ° C. or higher. Thus, even if the first pressure bonding step is performed at a low temperature, a semiconductor device sufficient in terms of void suppression and connection can be obtained through the subsequent second pressure bonding step and third pressure bonding step. it can.

The pressure load for pressing the laminate 3 to obtain the temporary pressure-bonded body 4 is appropriately set in consideration of the number of bumps, absorption of bump height variations, and control of the amount of bump deformation. In the temporary press-bonded body 4, the connection portion (bump 30) of the semiconductor chip 1 may be in contact with the connection portion (wiring 16) of the printed circuit board 2. As a result, metal bonding is likely to be formed in the subsequent steps, and the biting of the adhesive tends to be small. The pressing load for pressing the laminated body 3 to obtain the temporary pressure-bonded body 4 is, for example, 0.009 to 0. It may be 2N.

The time for pressurizing the laminate 3 to obtain the temporary pressure-bonded body 4 may be 5 seconds or less, 3 seconds or less, or 1 second or less from the viewpoint of improving productivity, and is 0.5 seconds or more. It is also good.

FIG. 2 shows a second pressure-bonding step of obtaining the pressure-bonded body 6 by pressurizing the temporary pressure-bonded body 4 while heating. As shown in (a) and (b) of FIG. 2, using a pressing device 46 prepared separately from the pressing device 43 and having a stage 45 and a crimping head 44 oppositely disposed as a pressing member for full crimping. And heat and press the temporary pressure bonding body 4. The temporary press-bonded body 4 is heated and pressurized by being pinched by the stage 45 and the press-contact head 44. In the case of the embodiment of FIG. 2, the pressure bonding head 44 is disposed on the semiconductor chip 1 side of the temporary pressure bonding body 4, and the stage 45 is disposed on the printed circuit board 2 side of the temporary pressure bonding body 4.

When at least one of the stage 45 and the pressure bonding head 44 heats and presses the temporary pressure bonding body 4, the melting point of the bump 30 as the connection portion of the semiconductor chip 1 or the wiring 16 as the connection portion of the printed circuit board 2 It is heated to a temperature equal to or higher than at least one of the melting points.

Generally, the oxide film on the surface of the connection portion may be removed by the second pressure bonding step. Therefore, the temperature of the stage 45 and / or the pressure bonding head 44 (that is, the heating temperature in the second pressure bonding step) can be set to a temperature at which the oxide film on the surface of the connection portion is efficiently removed. From such a viewpoint, the heating temperature in the second pressure bonding step may be 220 ° C. or more and 330 ° C. or less. When the metal material of the connection portion includes a solder, if the heating temperature in the second pressure bonding step is 220 ° C. or higher, the solder of the connection portion is melted and a sufficient metal bond is easily formed. When the temperature is 330 ° C. or less, voids are less likely to occur, and the solder is less likely to scatter. The heating temperature in the second pressure bonding step may be 220 ° C. or more even when the metal material of the connection portion includes Sn / Ag having a melting point of about 220 ° C.

The pressing load in the second pressure bonding step is appropriately set in consideration of oxide film removal on the surface of the connection portion, the number of bumps, absorption of bump height variations, control of the amount of bump deformation, and the like. When the pressing load is large, the oxide film tends to be easily removed. The pressing load may be, for example, 0.009 to 0.2 N per connection portion (bump) of the semiconductor chip. If the pressing load is 0.009 N or more, the oxide film formed on the connection portion is easily removed, and the adhesive is hardly trapped in the connection portion. In addition, when the pressing load is 0.2 N or less, it is difficult to cause a defect such as crushing or scattering of a bump containing solder or the like.

The adhesive may be partially cured by the second pressure-bonding step to such an extent that the adhesive has some fluidity in the third pressure-bonding step of heating the pressure-bonded body in a pressurized atmosphere. By causing the adhesive to flow as much as the adhesive in the third pressure bonding step, it is possible to further suppress the remaining of the voids in the adhesive layer. Moreover, the fillet around the connection portion can also be suppressed by setting the heat history applied to the adhesive in the second pressure bonding step to such an extent that the curing reaction rate remains small. From these viewpoints, the curing reaction rate of the adhesive after the second pressure bonding step may be 50% or less, 30% or less, 27% or less, or 25% or less.

The curing reaction rate of the adhesive after the second pressure bonding step is determined based on the change in the heating value due to the curing reaction, which is measured by differential scanning calorimetry. The heat generation amount ΔH (J / g) due to the curing reaction of the adhesive before the first pressure bonding step is “ΔH0”, and the heat generation amount ΔH (J / g) due to the curing reaction after the second pressure bonding step is “ΔH2” The curing reaction rate after the second pressure bonding step can be calculated by the following equation. Here, the curing reaction rate of the adhesive to be subjected to the first pressure bonding step is regarded as 0%.
Curing reaction rate (%) after the second pressure bonding step = (ΔH0−ΔH2) / ΔH0 × 100
The differential scanning calorimetry for measuring the calorific value due to the curing reaction can be performed at a temperature rising rate of 20 ° C./min, in the temperature range of 30 to 300 ° C. Instead of the actual pressure bonding process, using a hot plate, an oven, etc., measure the curing reaction rate using the adhesive after applying the heat history under the same conditions as the first pressure bonding process and the first pressure bonding process. Thus, the curing reaction rate after the second pressure bonding step can be estimated.

The curing reaction rate after the second pressure bonding step can be adjusted mainly based on the time of heating and pressing. For example, if the heating and pressing time in the second pressure bonding step is 3 seconds or less or 1 second or less, for example, the curing reaction rate becomes 50% or less, 30% or less, 27% or less, or 25% or less The adhesive can be cured.

The temporary pressure-bonding pressing member and the pressure-bonding pressing member may be respectively installed in two or more separate devices, or both may be installed in one device.

Subsequently, as shown in FIG. 3, the semiconductor device 100 is obtained through a third pressure bonding step of heating the pressure bonded body 6 in a pressure atmosphere in the heating furnace 60. The plurality of pressure-bonded bodies 6 can be collectively heated in one heating furnace 60. When a plurality of pressure-bonded bodies are collectively pressurized using a pressing member, it is difficult to uniformly heat the plurality of pressure-bonded bodies. On the other hand, the heating furnace can easily and uniformly heat a large number of pressure-bonded bodies, thereby improving the productivity. As a heating furnace, a reflow furnace, a pressure oven, etc. can be used.

When the crimped body is heated in a pressurized atmosphere, the fillet tends to be suppressed as compared with the case where the crimped body is heated and pressurized using the pressing member. Fillet suppression is particularly important in the manufacture of miniaturized and densified semiconductor devices. Here, fillet suppression means suppressing the fillet width to a small value, and the fillet width is the length of the adhesive that protrudes to the outer peripheral portion of the semiconductor device. The fillet width can be measured, for example, on an image obtained by photographing an appearance image of a semiconductor device with a digital microscope (VHX-5000 manufactured by KEYENCE). The length (fillet width) of the adhesive layer protruding from the four sides of the semiconductor chip is measured, and the average value is determined as a fillet value. The fillet value may be 150 μm or less from the viewpoint of mounting a large number of semiconductor chips or the like on a semiconductor wafer or a printed circuit board or the like.

The pressure-bonded body is heated in a state in which the inside of the heating furnace 60 is in a pressurized atmosphere. As used herein, "a pressurized atmosphere" means a gaseous atmosphere having a pressure greater than or equal to atmospheric pressure. The pressure in the heating furnace 60 may be 0.1 MPa or more and 0.8 MPa or less, or 0.2 MPa or more and 0.5 MPa or less. When the pressure is 0.1 MPa or more, the voids disappear particularly effectively. If the air pressure is 0.8 MPa or less, problems such as increased warpage of the semiconductor device are less likely to occur.

The heating temperature (atmosphere temperature in the heating furnace 60) in the third pressure bonding step may be a temperature at which the adhesive melts or a temperature above the glass transition temperature (Tg) of the adhesive, and the curing of the adhesive It may be the temperature at which The ambient temperature in the heating furnace 60 may be, for example, 130 ° C. or more and 300 ° C. or less, or 140 ° C. or more and 270 ° C. or less. When the temperature is 130 ° C. or higher, the adhesive is likely to be appropriately cured while having fluidity to some extent, and there is a tendency for voids to be particularly effectively suppressed by pressure. When the temperature is 300 ° C. or less, voids are particularly suppressed, and warpage of the semiconductor device is less likely to occur. When raising the atmosphere in the heating furnace 60 as described later, the highest reachable temperature may be in the above range.

The heating and pressing times in the third pressure bonding step are set to such an extent that the curing of the adhesive proceeds sufficiently. For example, the time during which the ambient temperature in the heating furnace 60 is 130 ° C. or more and 300 ° C. or less may be 1 minute or more and 120 minutes or less, or 5 minutes or more and 60 minutes or less.

During the third pressure bonding step, the atmosphere in the heating furnace 60 may be heated. The temperature raising rate in that case is not particularly limited, but may be 5 ° C./min or more and 300 ° C./min or less, or 10 ° C./min or more and 250 ° C./min or less. When the temperature rise rate is 5 ° C./min or more, the productivity is improved, and the void tends to be particularly effectively eliminated. If the temperature rise rate is 300 ° C./min or less, problems such as void formation due to rapid temperature rise hardly occur.

A connection body in which the adhesive is further adhered by the adhesive layer 40 in which the semiconductor chip 1 (first member) and the printed circuit board 2 (second member) are cured by further curing the adhesive in the third pressure bonding step. (Semiconductor device 100) can be formed. The curing reaction rate of the adhesive after the third pressure bonding step may be 80% or more, 85% or more, or 90% or more. When the curing reaction rate of the adhesive after the third pressure bonding step is 80% or more, the generation of voids resulting from spring back and the like can be more effectively suppressed.

The cure reaction rate of the adhesive after the third pressure bonding step is also determined based on the change in heating value due to the curing reaction, which is measured by differential scanning calorimetry. The heat generation amount ΔH (J / g) due to the curing reaction of the adhesive before the first pressure bonding step is “ΔH0”, and the heat generation amount ΔH (J / g) due to the curing reaction after the third pressure bonding step is “ΔH3” The curing reaction rate after the second pressure bonding step can be calculated by the following equation.
Curing reaction rate (%) after the third pressure bonding step = (ΔH0−ΔH3) / ΔH0 × 100
The conditions for differential scanning calorimetry are the same as in the method for determining the curing reaction rate after the second pressure bonding step.

The atmosphere in the heating furnace 60 is not particularly limited, but may be air, nitrogen, formic acid, or the like.

From the viewpoint of improving productivity, a semiconductor wafer may be used as at least one of the first member and the second member. As an example thereof, there are CoW (Chip On Wafer) in which a semiconductor chip is connected to a semiconductor wafer and then singulated, and WoW (Wafer On Wafer) in which semiconductor wafers are pressure bonded to each other.

(Semiconductor device)
FIG.4, FIG.5, FIG.6 and FIG. 7 are respectively sectional drawings which show one another embodiment of the semiconductor device which can be manufactured by the method based on the above-mentioned embodiment.

The semiconductor device 200 shown in FIG. 4 includes a semiconductor chip 1 (first member) having a semiconductor chip body 10, a printed circuit board 2 (second member) having a substrate body 20, and an adhesive interposed therebetween. And an agent layer 40. In the case of the semiconductor device 200, the semiconductor chip has the bumps 32 disposed on the surface of the semiconductor chip on the side of the printed circuit board 2 as the connection portion. The printed circuit board 2 has a bump 33 disposed on the surface of the substrate body 20 on the semiconductor chip side as a connection portion. The bumps 32 of the semiconductor chip 1 and the bumps 33 of the printed circuit board 2 are electrically connected by metal bonding. That is, the semiconductor chip 1 and the printed circuit board 2 are flip chip connected by the bumps 32 and 33. The bumps 32 and 33 are sealed from the external environment by being sealed by the adhesive layer 40.

5 and 6 show a CoC type semiconductor device which is a connection body in which semiconductor chips are connected to each other. The configuration of the semiconductor device 300 shown in FIG. 5 is the same as that of the semiconductor device 100 except that two semiconductor chips are flip chip connected as the first member and the second member via the wiring 15 and the bumps 30. It is. The configuration of the semiconductor device 400 shown in FIG. 6 is the same as that of the semiconductor device 200 except that two semiconductor chips 1 are flip-chip connected via bumps 32.

In the semiconductor devices 100, 200, 300, and 400 shown in FIGS. 3 to 6, the connection portions such as the wiring 15 and the bumps 32 may be metal films (for example, gold plating) called pads, and post electrodes (For example, a copper pillar) may be used. For example, in (b) of FIG. 2, even if one semiconductor chip has copper pillars and connection bumps (solder: tin-silver) as connection parts and the other semiconductor chip has gold plating as connection parts. Good. In this case, the connection portion may reach a temperature equal to or higher than the melting point of the solder having the lowest melting point among the metal materials forming the surface of the connection portion.

The semiconductor chip body 10 is not particularly limited, and various semiconductors such as an elemental semiconductor composed of the same kind of element such as silicon and germanium, and a compound semiconductor such as gallium arsenide and indium phosphide can be used.

The wiring circuit board 2 is not particularly limited, and has an insulating substrate mainly composed of glass epoxy, polyimide, polyester, ceramic, epoxy, bismaleimide triazine, etc. as a substrate main body, and a metal layer formed on the surface A circuit board on which wiring (wiring pattern) is formed by etching away unnecessary portions of the circuit, a circuit board on which wiring (wiring pattern) is formed on the surface of the insulating substrate by metal plating, etc., conductive on the surface of the insulating substrate It is possible to use a circuit board or the like on which a wiring (wiring pattern) is formed by printing a conductive material.

Gold, silver, copper, solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, etc.) as the main components of the connection parts such as the wirings 15 and 16, the bumps 30, the bumps 32 and 33, etc. , Tin-copper, tin-silver-copper), tin, nickel and the like are used. The connection part may be composed of only a single component or may be composed of a plurality of components. The connection portion may have a structure in which these metals are stacked. Among metal materials, copper and solder are relatively inexpensive. The connection portion may include solder from the viewpoint of improving connection reliability and suppressing warpage.

The material of the pad is, as a main component, gold, silver, copper, solder (for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper), tin, nickel Etc. are used. The pad may be composed of only a single component or may be composed of a plurality of components. The pad may have a structure in which these metals are stacked. From the viewpoint of connection reliability, the pad may contain gold or solder.

Gold, silver, copper, solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper), tin, nickel, etc. on the surfaces of the wirings 15 and 16 (wiring pattern) A metal layer as a component may be formed. The metal layer may be composed of only a single component or may be composed of a plurality of components. The metal layer may have a structure in which a plurality of metal layers are stacked. The metal layer may comprise relatively inexpensive copper or solder. The metal layer may contain a solder from the viewpoint of improving connection reliability and suppressing warpage.

Semiconductor devices (packages) such as semiconductor devices 100, 200, 300, and 400 are stacked and gold, silver, copper, solder (the main components are, for example, tin-silver, tin-lead, tin-bismuth, tin- Electrical connection may be made with copper, tin-silver-copper), tin, nickel or the like. The metal for connection may be relatively inexpensive copper or solder. For example, an adhesive layer may be flip-chip connected or laminated between semiconductor chips, as in TSV technology, to form holes penetrating the semiconductor chips, and be connected to electrodes on the pattern surface.

FIG. 7 is a cross-sectional view showing another embodiment of the semiconductor device. The semiconductor device 500 shown in FIG. 7 has a TSV structure in which a plurality of semiconductor chips are stacked. In the semiconductor device 500 shown in FIG. 7, the semiconductor chip 1 and the interposer 5 are flip chip by connecting the wiring 15 formed on the interposer main body 50 as a wiring circuit board to the bumps 30 of the semiconductor chip 1. It is connected. An adhesive layer 40 is interposed between the semiconductor chip 1 and the interposer 5. The semiconductor chip 1 is repeatedly stacked on the surface of the semiconductor chip 1 opposite to the interposer 5 via the wiring 15, the bumps 30 and the adhesive layer 40. The wirings 15 on the pattern surface on the front and back of the semiconductor chip 1 are connected to each other by a through electrode 34 filled in a hole that penetrates the inside of the semiconductor chip main body 10. As a material of the through electrode 34, copper, aluminum or the like can be used.

According to the semiconductor device of the TSV (Through-Silicon Via) structure as illustrated in FIG. 7, it is possible to acquire a signal also from the back surface of the semiconductor chip which is not normally used. Furthermore, since the through electrodes 34 are vertically passed through the semiconductor chip 1, the distance between the facing semiconductor chips 1 and the distance between the semiconductor chip 1 and the interposer 5 can be shortened, and flexible connection is possible.

In the case of the semiconductor device 500 of FIG. 7, a plurality of semiconductor chips 1 are stacked one by one and temporary temporary pressure bonding is performed, and then a pressure bonding body is obtained by the second pressure bonding step, and finally a plurality of semiconductor chips are collectively pressed. It may be heated under an atmosphere.

As another example of the semiconductor device having a multilayer semiconductor chip, there is also a chip stack type package, POP (Package On Package), which can also be manufactured by the same method as TSV.

These are also effective for reducing the mounting area by further reducing the size and thickness of the semiconductor device, enhancing the function, reducing noise, and saving power.

(adhesive)
Hereinafter, an adhesive (thermosetting adhesive) that can be used in the above-described method of manufacturing a semiconductor device will be described.

The adhesive according to one embodiment contains a thermosetting resin and its curing agent. The adhesive may further contain a polymer component having a weight average molecular weight of 10000 or more.

<Thermosetting resin>
The weight average molecular weight of the thermosetting resin may be less than 10000. The thermosetting resin having a weight average molecular weight of less than 10000 reacts with the curing agent to improve the curability of the adhesive. It is also advantageous in terms of void suppression and heat resistance.

As a thermosetting resin, an epoxy resin and an acrylic resin are mentioned, for example.

The epoxy resin is not particularly limited as long as it has two or more epoxy groups in the molecule. As epoxy resin, use bisphenol A type, bisphenol F type, naphthalene type, phenol novolak type, cresol novolak type, phenol aralkyl type, biphenyl type, triphenylmethane type, dicyclopentadiene type, various multifunctional epoxy resins, etc. Can. These can be used alone or as a mixture of two or more.

The acrylic resin is not particularly limited as long as it has one or more (meth) acrylic groups in the molecule. As an acrylic resin, for example, bisphenol A type, bisphenol F type, naphthalene type, phenol novolak type, cresol novolak type, phenol aralkyl type, biphenyl type, triphenylmethane type, dicyclopentadiene type, fluorene type, adamantane type, various types A functional acrylic resin etc. can be used. These can be used alone or as a mixture of two or more. In the present specification, “(meth) acrylic group” is used as a term that means either an acrylic group or a methacrylic group.

The acrylic resin may be solid at room temperature (25 ° C.). Solids are less likely to generate voids than liquid, and the viscosity (tack) of the B-stage adhesive before curing is small, and tends to be excellent in handling.

The number of (meth) acrylic groups contained in the acrylic resin may be 3 or less per molecule. If the number of (meth) acrylic groups is 3 or less, curing tends to proceed sufficiently in a short time until the remaining unreacted groups are reduced.

The content of the thermosetting resin in the adhesive is, for example, 10 to 50 parts by mass with respect to 100 parts by mass of the total mass of the adhesive (the mass of components other than the solvent). When the content of the thermosetting resin is 10 parts by mass or more, the flow of the adhesive after curing tends to be easily controlled. When the content of the thermosetting resin is 50 parts by mass or less, warpage of the semiconductor device tends to be suppressed.

<Hardening agent>
The curing agent can be a compound that reacts with the thermosetting resin, a compound that functions as a catalyst for the curing reaction of the thermosetting resin, or a combination of these. Examples of curing agents include phenol resin-based curing agents, acid anhydride-based curing agents, amine-based curing agents, imidazole-based curing agents, phosphine-based curing agents, azo compounds, and organic peroxides. Among these, an imidazole curing agent may be used.

The phenol resin-based curing agent is not particularly limited as long as it has two or more phenolic hydroxyl groups in the molecule, and examples thereof include phenol novolak, cresol novolac, phenol aralkyl resin, cresol naphthol formaldehyde polycondensate, Examples include triphenylmethane-type polyfunctional phenols and various polyfunctional phenol resins. These can be used alone or as a mixture of two or more.

The equivalent ratio (phenolic hydroxyl group / epoxy group, molar ratio) of the phenolic resin-based curing agent to the thermosetting resin is 0.3 to 1.5, 0 from the viewpoint of good curability, adhesiveness and storage stability. .4 to 1.0, or 0.5 to 1.0. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive strength tends to be improved. When the equivalent ratio is 1.5 or less, the unreacted phenolic hydroxyl group does not remain excessively, and the water absorption is increased. It tends to be low and insulation reliability improves.

Examples of the acid anhydride curing agent include methylcyclohexanetetracarboxylic acid dianhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic acid dianhydride, and ethylene glycol bisanhydrotrimellitate. These can be used alone or as a mixture of two or more.

The equivalent ratio (acid anhydride group / epoxy group, molar ratio) of the acid anhydride based curing agent to the thermosetting resin is 0.3 to 1.5 from the viewpoint of good curability, adhesiveness and storage stability. , 0.4 to 1.0, or 0.5 to 1.0. If the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive strength tends to be improved, and if it is 1.5 or less, the unreacted acid anhydride does not remain excessively, and the water absorption rate is increased. It tends to be low and insulation reliability improves.

As an amine curing agent, for example, dicyandiamide can be used.

The equivalent ratio (amine / epoxy group, molar ratio) of the amine curing agent to the thermosetting resin is 0.3 to 1.5, 0.4 to 1 from the viewpoint of good curability, adhesion and storage stability. .0, or 0.5 to 1.0. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive strength tends to be improved, and when it is 1.5 or less, the unreacted amine does not remain excessively, and the insulation reliability is improved. There is a tendency to

Examples of the imidazole-based curing agent include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl -(1 ')-ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [4 2'-Ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2, -Diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2 And -phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins and imidazoles. From the viewpoint of excellent curability, storage stability and connection reliability, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1- Cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′- Ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine isocyanuric acid adduct , 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4- From chill-5-hydroxymethylimidazole may select the imidazole curing agent. These can be used alone or in combination of two or more. Microcapsules containing these can also be used as latent hardeners.

The content of the imidazole-based curing agent may be 0.1 to 20 parts by mass, or 0.1 to 10 parts by mass with respect to 100 parts by mass of the thermosetting resin. When the content of the imidazole-based curing agent is 0.1 parts by mass or more, the curability tends to be improved, and when the content is 20 parts by mass or less, the adhesive does not cure before metal bonding is formed, There is a tendency for poor connection to be less likely to occur.

The phosphine-based curing agent includes, for example, triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra (4-methylphenyl) borate and tetraphenylphosphonium (4-fluorophenyl) borate.

The content of the phosphine-based curing agent may be 0.1 to 10 parts by mass, or 0.1 to 5 parts by mass with respect to 100 parts by mass of the thermosetting resin. When the content of the phosphine-based curing agent is 0.1 parts by mass or more, the curability tends to be improved, and when the content is 10 parts by mass or less, the adhesive does not cure before metal bonding is formed, There is a tendency for poor connection to be less likely to occur.

The phenol resin-based curing agent, the acid anhydride-based curing agent and the amine-based curing agent can be used alone or in combination of two or more. The imidazole-based curing agent and the phosphine-based curing agent may be used alone, but may be used together with a phenol resin-based curing agent, an acid anhydride-based curing agent or an amine-based curing agent.

Examples of organic peroxides include ketone peroxides, peroxy ketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxy dicarbonates, and peroxy esters. From the viewpoint of storage stability, hydroperoxides, dialkyl peroxides, or peroxy esters may be selected. Furthermore, hydroperoxide or dialkyl peroxide may be selected from the viewpoint of heat resistance. These can be used alone or as a mixture of two or more.

The content of the organic peroxide may be 0.5 to 10% by mass, or 1 to 5% by mass with respect to the acrylic resin. When the content of the organic peroxide is 0.5% by mass or more, curing tends to proceed sufficiently. If the content of the organic peroxide is 10% by mass or less, the decrease in reliability due to the shortening of the molecular chain after curing or the remaining of the unreacted group tends to be suppressed.

The curing agent to be combined with the epoxy resin or the acrylic resin is not particularly limited as long as curing proceeds. The curing agent to be combined with the epoxy resin is a combination of a phenol resin-based curing agent and an imidazole-based curing agent, a combination of an acid anhydride-based curing agent and an imidazole-based curing agent, and an amine from the viewpoint of handleability, storage stability and curability. A combination of a system curing agent and an imidazole curing agent, or an imidazole curing agent alone may be used. If the connection is made in a short time, the productivity is improved, and therefore, an imidazole-based curing agent excellent in quick curing may be used alone. When curing is performed in a short time, volatile components such as low molecular weight components can be suppressed, and void generation can also be suppressed. The curing agent to be combined with the acrylic resin may be an organic peroxide from the viewpoint of handleability and storage stability.

<Polymer Component of Weight Average Molecular Weight 10000 or More>
The polymer component having a weight average molecular weight of 10000 or more can be a thermosetting resin, a thermoplastic resin, or a combination thereof. Examples of the polymer component include epoxy resin, phenoxy resin, polyimide resin, polyamide resin, polycarbodiimide resin, cyanate ester resin, acrylic resin, polyester resin, polyethylene resin, polyether sulfone resin, polyether imide resin, polyvinyl acetal resin And urethane resins and acrylic rubbers. An epoxy resin, a phenoxy resin, a polyimide resin, an acrylic resin, an acrylic rubber, a cyanate ester resin, or a polycarbodiimide resin which is excellent in heat resistance and film formation may be selected. An epoxy resin, a phenoxy resin, a polyimide resin, an acrylic resin, or an acrylic rubber which is excellent in heat resistance and film formation may be selected. These polymer components can be used alone or as a mixture or copolymer of two or more. The polymer component having a weight average molecular weight of 10000 or more may be a thermosetting resin that reacts with the curing agent.

The mass ratio of the polymer component to the epoxy resin as the above-mentioned thermosetting resin is not particularly limited. The weight ratio of the epoxy resin to the polymer component may be 0.01 to 5, 0.05 to 4, or 0.1 to 3 in order for the adhesive to maintain a film-like form. When the mass ratio is 0.01 or more, the curability is improved, and the adhesion tends to be further improved. Favorable film formation property is easy to be obtained as this mass ratio is 5 or less.

The mass ratio of the polymer component and the acrylic resin as the above-mentioned thermosetting resin is not particularly limited. The mass ratio of the acrylic resin to the polymer component may be 0.01 to 10, 0.05 to 5, or 0.1 to 5. When the mass ratio is 0.01 or more, the curability is improved, and the adhesion tends to be further improved. Favorable film formation property is easy to be obtained as this mass ratio is 10 or less.

The glass transition temperature (Tg) of the polymer component may be 50 ° C. or more and 200 ° C. or less from the viewpoint of excellent adhesion to the printed circuit board or semiconductor chip of the adhesive. When the Tg of the polymer component is 50 ° C. or more, the tack (viscous) force of the adhesive tends to be moderately weak. When the Tg of the polymer component is 200 ° C. or less, the adhesive tends to embed irregularities such as bumps of a semiconductor chip, electrodes formed on a wiring circuit board, and a wiring pattern, and the effect of suppressing voids tends to be relatively large. There is. The Tg herein is measured using a DSC (DSC-7, manufactured by PerkinElmer, Inc.) at a sample amount of 10 mg, a temperature rising rate of 10 ° C./min, under conditions of an air atmosphere.

The weight average molecular weight of the polymer component is 10000 or more. The weight average molecular weight of the polymer component may be 30,000 or more, 40000 or more, or 50000 or more, or 500,000 or less in order to exhibit good film-forming property alone. In the present specification, the weight average molecular weight means a value in terms of standard polystyrene, which is measured by gel permeation chromatography (GPC).

The adhesive can contain a flux activator which is a compound that exhibits flux activity (activity to remove oxides and impurities). Flux activators include nitrogen-containing compounds having non-covalent electron pairs such as imidazoles and amines, carboxylic acids, phenols and alcohols. The organic acid more strongly exhibits the flux activity than the alcohol etc., and the connectivity is improved.

The organic acid that can be used as a flux activator may be a carboxylic acid because the acid is unlikely to remain in the adhesive by reacting with an epoxy resin or the like. The carboxylic acid may be solid from the viewpoint of heat resistance. The melting point of the carboxylic acid may be 70 ° C. or more and 150 ° C. or less from the viewpoint of stability and handleability.

Even if the adhesive contains a filler, in order to control the viscosity and physical properties of the cured product, and to suppress the generation of voids and moisture absorption when the semiconductor chips or the semiconductor chips and the wiring circuit board are connected to each other. Good. The filler may be an insulating inorganic filler, and examples thereof include glass, silica, alumina, titanium oxide, carbon black, mica, boron nitride and the like. Among these, a filler selected from silica, alumina, titanium oxide and boron nitride, or silica, alumina and boron nitride may be used. The filler may be a whisker, examples of which include aluminum borate, aluminum titanate, zinc oxide, calcium silicate, magnesium sulfate and boron nitride. The filler may be a resin filler, examples of which include polyurethane, polyimide, methyl methacrylate resin, and methyl methacrylate-butadiene-styrene copolymer resin (MBS). These fillers may be used alone or in combination of two or more. The shape, particle size and content of the filler are not particularly limited.

The resin filler can impart flexibility at a high temperature such as 260 ° C., as compared with the inorganic filler, and thus is suitable for improving the reflow resistance. The resin filler is also advantageous in terms of film formability improvement.

From the viewpoint of insulation reliability, the filler may be insulating. The adhesive may be substantially free of a conductive metal filler such as a silver filler or a solder filler.

The filler may be surface-treated from the viewpoint of dispersibility and adhesion. The filler is surface-treated with, for example, a glycidyl-based (epoxy-based), amine-based, phenyl-based, phenylamino-based, (meth) acrylic-based or vinyl-based surface treating agent. The filler may be surface-treated with a glycidyl-based, phenylamino-based or (meth) acrylic-based surface treatment agent from the viewpoint of dispersibility, fluidity, and adhesive strength. From the viewpoint of storage stability, the surface treatment agent may be phenyl type, acrylic type or (meth) acrylic type. From the ease of surface treatment, the surface treatment agent may be a silane compound such as epoxysilane type, aminosilane type and acrylic silane type.

The average particle diameter of the filler may be 1.5 μm or less from the viewpoint of preventing biting at the time of flip chip connection, and may be 1.0 μm or less from the viewpoint of visibility and transparency.

The content of the filler may be 30 to 90% by mass, or 40 to 80% by mass, based on the mass of the solid content of the adhesive (the mass of components other than the solvent). When the content of the filler is 30% by mass or more, the heat dissipation property is high, and the void generation and the moisture absorption ratio tend to be small. When the content of the filler is 90% by mass or less, the adhesive has appropriate fluidity, and a decrease in connection reliability due to trapping of the filler in the connection portion tends to be suppressed.

The adhesive may further include other components such as an ion trapper, an antioxidant, a silane coupling agent, a titanium coupling agent, and a leveling agent. One of these may be used alone, or two or more of these may be used in combination. About these compounding quantities, what is necessary is just to adjust suitably so that the effect of each additive may be revealed.

The minimum melt viscosity of the adhesive may be 3000 Pa · s or less, or 2700 Pa · s or less, or 300 Pa · s or more from the viewpoint of void suppression. The minimum melt viscosity of the adhesive is the viscosity (complex viscosity) obtained when the viscoelasticity of the adhesive is measured in the temperature range of 30 to 300 ° C. under the conditions of temperature increase rate 10 ° C./min, frequency 10 Hz and rotational mode The viscosity value is the lowest in terms of viscosity in relation to temperature). As a test piece for viscoelasticity measurement, for example, a laminate obtained by laminating a plurality of film-like adhesives so as to have a thickness of 300 to 450 μm may be used. As a viscosity measuring device, for example, ARES G2 manufactured by TA can be used.

The adhesive may be in the form of a film from the viewpoint of improving the production efficiency of the semiconductor device. The film-like adhesive can be produced by a method of applying a resin varnish containing a thermosetting resin, a curing agent and, if necessary, other components to an equipment film and drying the coating.

The resin varnish is prepared by mixing a thermosetting resin curing agent and, if necessary, other components with an organic solvent, and dissolving or dispersing them by stirring or kneading. The resin varnish is applied onto the release-treated substrate film using, for example, a knife coater, a roll coater, an applicator, a die coater, or a comma coater. Thereafter, the organic solvent is reduced from the resin varnish coating by heating, that is, the coating is dried to form a film-like adhesive on the substrate film. A film of resin varnish may be formed on a semiconductor wafer or the like by a method such as spin coating, and then a film-like adhesive may be formed on the semiconductor wafer by a method of drying the coating film.

The substrate film is not particularly limited as long as it has heat resistance that can withstand the heating conditions at the time of volatilizing the organic solvent, and a polyester film, a polypropylene film, a polyethylene terephthalate film, a polyimide film, a polyetherimide film, a poly An ether naphthalate film, a methyl pentene film, etc. can be illustrated. The substrate film is not limited to a single layer film composed of these films, and may be a multilayer film composed of two or more materials.

Specifically, the conditions for volatilizing the organic solvent from the resin varnish after application may be heating at 50 to 200 ° C. for 0.1 to 90 minutes. The organic solvent may be removed to a residual amount of 1.5% by mass or less within a range not substantially affecting the preparation of voids and viscosity after mounting.

EXAMPLES Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited to these examples.

Examination 1
(1-1) Film Adhesive A film adhesive (thickness 0.045 mm) having the composition shown in Table 1 was produced using the materials shown below.
(I) Thermosetting resin (epoxy resin) having a weight average molecular weight of less than 10000
・ Triphenol methane skeleton-containing polyfunctional solid epoxy resin (Mitsubishi Chemical Corporation, product name: EP1032H60, weight average molecular weight: 800 to 2000)
-Bisphenol F type liquid epoxy resin (Mitsubishi Chemical Corporation, product name: YL 983 U, weight average molecular weight: about 336)
Flexible semi-solid epoxy resin (Mitsubishi Chemical Corporation, product name: YL7175-1000, weight average molecular weight: 1000-5000)
(Ii) Hardening agent 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct (manufactured by Shikoku Kasei Kogyo Co., Ltd., product name: 2MAOK-PW )
(Iii) Polymer component having a weight average molecular weight of 10000 or more phenoxy resin (manufactured by Nippon Steel Sumikin Chemical Co., Ltd., product name: ZX 1356-2, Tg: about 71 ° C., weight average molecular weight: about 63000, hereinafter referred to as “ZX1356”)
(Iv) Flux agent (carboxylic acid)
2-Methylglutaric acid (Sigma-Aldrich, melting point about 77 ° C)
(V) Filler (inorganic filler)
・ Silica filler (made by Admatex Co., Ltd., product name: SE2050, average particle diameter 0.5 μm)
・ Finil surface-treated nano silica filler (Admatex Co., Ltd., product name: YA050C-SP (hereinafter referred to as “SP nano silica”), average particle diameter about 50 nm)
(Resin filler)
・ Organic filler (Dow Chemical Japan Ltd. product name: EXL-2655, core-shell type organic fine particles)

(1-2) Fabrication of Semiconductor Device (Example 1)
First pressure bonding step The produced film adhesive was cut out to prepare a film adhesive having a size of 8 mm × 8 mm × thickness 0.045 mm. This was attached to a semiconductor chip (10 mm, thickness 0.1 mm, connection metal: Au, product name: WALTS-TEG IP80, manufactured by WALTS). There, a semiconductor chip with solder bumps (chip size: 7.3 mm × 7.3 mm × thickness 0.05 mm, solder bump melting point: about 220 ° C., bump height: about 45 μm in total of copper pillars and solder, bump number 1048 A pin, pitch 80 um, product name: WALTS-TEG CC80 (manufactured by WALTS) was attached to obtain a laminate. The laminate is placed on a stage of a flip chip bonder (FCB3, manufactured by Panasonic Corporation) having a stage and a crimping head, and the laminate is pressed with a load of 25 N for 1 second by a thermal press sandwiched by the stage and the crimping head. While heating to 80 ° C., a temporary press-bonded body was obtained.

Second pressure bonding process The obtained temporary pressure bonding body is moved onto the stage of another flip chip bonder (FCB3, manufactured by Panasonic Corporation), and is sandwiched by the stage and the pressure bonding head, while being pressurized with a load of 25 N 230 The press-bonded body was obtained by a heat press which is heated at 1 ° C. for 1 second.

Third Crimping Process The crimped body was placed in an oven of a pressure reflow apparatus (manufactured by Shin Apex, product name: VSU 28). The pressure in the oven was set to 0.4 MPa, and the temperature was raised from room temperature to 175 ° C. at a heating rate of 20 ° C./min. Subsequently, the pressure-bonded body was heated for 10 minutes in a pressurized atmosphere while maintaining the pressure and the temperature to obtain a semiconductor device sample for evaluation.

(Example 2)
A semiconductor device sample for evaluation was obtained in the same manner as in Example 1 except that the heating temperature at the time of heating the pressure-bonded body in the oven of the pressure reflow apparatus was changed from 175 ° C. to 260 ° C.

(Comparative example 1)
A temporary crimped body was obtained in the same manner as in Example 1. The obtained temporary pressure-bonded body was heated at 175 ° C. for 10 minutes under atmospheric pressure in an oven (manufactured by Yamato Scientific Co., Ltd., product name: DKN 402) to obtain a semiconductor device sample for evaluation.

(Comparative example 2)
A semiconductor device sample for evaluation was obtained in the same manner as in Comparative Example 1 except that the heating temperature at the time of heating the temporary pressure-bonded body at atmospheric pressure was changed from 175 ° C. to 260 ° C.

(Comparative example 3)
A crimped body was obtained under the same conditions as in Example 1. The obtained crimped body was heated at 175 ° C. for 10 minutes under atmospheric pressure in an oven (manufactured by Yamato Scientific Co., Ltd., product name: DKN 402) to obtain a semiconductor device sample for evaluation.

(Comparative example 4)
A semiconductor device sample for evaluation was obtained in the same manner as in Comparative Example 3 except that the heating temperature when heating the pressure-bonded body using an oven was changed from 175 ° C. to 260 ° C.

(1-3) Connection Evaluation Whether the initial conduction of the sample was possible was measured using a multimeter (manufactured by ADVANTEST, product name: R6871E). The connectivity was judged based on the following criteria. The results are shown in Table 2.
A: Initial connection resistance value of peripheral part is 30 Ω or more and 35 Ω or less B: Initial connection resistance value is less than 30 Ω or more than 35 Ω or not connected

(1-4) Void evaluation The external appearance image of the sample was taken with an ultrasonic diagnostic imaging apparatus (product name: Insight-300, manufactured by Insight). From the obtained image, a portion of the adhesive layer on the chip was taken in with a scanner (product name: GT-9300UF, manufactured by Seiko Epson Corporation). Using the image processing software Adobe Photoshop, the void portion was identified by color tone correction and two gradations, the area of the adhesive layer was 100%, and the percentage of void portion (void occurrence rate) was calculated by a histogram. The occurrence of voids was evaluated according to the following criteria. The results are shown in Table 2.
A: Void generation rate is 5% or less B: Void generation rate is more than 5%

Examples 1 and 2 both showed good results in terms of void suppression and connection securing. That is, according to the method of the present invention, it was confirmed that compatibility between void suppression and connection securing can be achieved.

Examination 2
(2-1) Film Adhesive The film adhesive (having a thickness of 0.040 to 0.045 mm) having the composition shown in Table 3 using the same material as the material used for producing the film adhesive of Study 1. ) Was produced.

(2-2) Fabrication of Semiconductor Device and Evaluation Thereof A semiconductor device sample for evaluation was obtained under the same conditions as in Example 1. The connection and void of the obtained sample were evaluated in the same manner as in Study 1. The results are shown in Table 4.

(2-3) Minimum Melt Viscosity The film adhesive has a total thickness of 300 to 450 μm while being heated to 60 ° C. using a roll laminator (HOT DOG Leon 13 DX, manufactured by Lamy Corporation). As shown, several sheets were stacked. The resulting laminate is used as a test piece, using a rotary rheometer (TA product, ARES G2), at a temperature rising rate of 10 ° C./min, frequency: 10 Hz, temperature range of 20 ° C. to 300 ° C. The change in viscosity (complex viscosity) was measured. The minimum value of viscosity at the measured viscosity change was taken as the lowest melt viscosity.

(2-6) Curing reaction rate after the third pressure bonding step A 10 mg sample is taken from the film adhesive before being used in the first pressure bonding step, and a DSC (DSC-7 manufactured by Perkin Elmer) is used. Then, differential scanning calorimetry at a temperature range of 30 to 300 ° C. was performed at a temperature rising rate of 20 ° C./min. From the DSC thermogram obtained, the calorific value ΔH0 (J / g) due to the initial curing reaction was determined.
To the film adhesive was added a heat history corresponding to the first, second and third pressure bonding steps as in Example 1 using a hot plate and an oven. Then, the calorific value ΔH3 (J / g) due to the curing reaction of the adhesive corresponding after the third pressure bonding step was determined by differential scanning calorimetry under the same conditions as above using the sample taken from the film adhesive . From the obtained ΔH 0 and ΔH 3, the curing reaction rate after the third pressure bonding step was calculated by the following equation.
Curing reaction rate (%) after the third pressure bonding step: (ΔH 0 −ΔH 3) / ΔH 0 × 100

Examples 3 and 4 all showed good evaluation results in terms of void suppression and connection securing.

Examination 3
(3-1) Film Adhesive The film adhesive (thickness 0.045 mm) having the composition shown in Table 5 was produced using the same material as the material used in the production of the film adhesive of Study 1. .

(3-2) Fabrication of Semiconductor Device (Example 5)
A semiconductor device sample for evaluation was obtained in the same manner as in Example 1 except that the time for heating and pressing the laminate in the first pressure bonding step was changed to 3 seconds.

(Example 6)
Evaluation was performed in the same manner as in Example 1 except that the time for heating and pressing the laminate in the first pressure bonding step was changed to 3 seconds, and the pressure in the oven was changed to 0.8 MPa in the third pressure bonding step. Semiconductor device samples for

(Comparative example 5)
The film adhesive was cut out, and a film adhesive having a size of 8 mm × 8 mm × thickness 0.045 mm was prepared. This was attached on a semiconductor chip (10 mm, thickness 0.1 mm, connection metal: Au, product name: WALTS-TEG IP80, manufactured by WALTS). Semiconductor chip with solder bumps (chip size: 7.3mm x 7.3mm x thickness 0.05mm, bump melting point: about 220 ° C bump height: about 45μm in total of copper pillar and solder, bump number 1048 pins , Pitch 80 um, product name: WALTS-TEG CC80, manufactured by WALTS), and a laminate was obtained. The laminate was placed on a stage of a flip chip bonder (FCB3, manufactured by Panasonic Corporation) having a stage and a pressure bonding head. A temporary press-bonded body was obtained by a heat press which is heated at a temperature of 80 ° C. while pressing with a load of 25 N for 3 seconds by clamping with a stage and a press-bonding head. The obtained temporary crimped body was moved onto the stage of another flip chip bonder (FCB3, manufactured by Panasonic Corporation). By holding the temporary pressure-bonded body between the stage and the pressure-bonding head, the semiconductor device sample for evaluation was obtained by heating at a temperature of 260 ° C. while pressing with a load of 25 N for 5 seconds.

(3-3) Evaluation The connection and void of the obtained semiconductor device sample were evaluated in the same manner as in Study 1. The results are shown in Table 6.

(3-4) Curing reaction rate after the second pressure bonding step A 10 mg sample is taken from the film adhesive before being used in the first pressure bonding step, and a DSC (DSC-7 manufactured by Perkin Elmer) is used. Then, differential scanning calorimetry at a temperature range of 30 to 300 ° C. was performed at a temperature rising rate of 20 ° C./min. From the DSC thermogram obtained, the calorific value ΔH0 (J / g) due to the initial curing reaction was determined.
To the film adhesive was added a heat history corresponding to the first and second pressure bonding steps as in Examples 5 and 6 using a hot plate and an oven. Then, the calorific value ΔH2 (J / g) due to the curing reaction of the adhesive corresponding to after the second pressure bonding step was determined by differential scanning calorimetry under the same conditions as above using the sample taken from the film adhesive . From the obtained ΔH 0 and ΔH 2, the curing reaction rate after the second pressure bonding step was calculated by the following equation.
Curing reaction rate (%) after the second pressure bonding step: (ΔH0-ΔH2) / ΔH0 × 100

(3-5) Fillet Evaluation An appearance image of a semiconductor device sample was taken with a digital microscope (VHX-5000 manufactured by KEYENCE). From the obtained image, measure the length (length in the direction parallel to the main surface of the semiconductor chip) of the adhesive layer protruding from each of the four peripheral sides of the semiconductor chip, and record the average value of the measured values as the fillet value. did.

Examples 1 and 2 all showed good evaluation results in terms of void suppression and connection securing.

DESCRIPTION OF SYMBOLS 1 ... semiconductor chip, 2 ... wiring circuit board, 3 ... laminated body, 4 ... temporary crimping body, 5 ... interposer, 6 ... crimping body, 10 ... semiconductor chip body, 15, 16 ... wiring, 20 ... board body, 30 , 32, 33: bump, 34: penetrating electrode, 40: adhesive layer, 41, 44: crimping head, 42, 45: stage, 43, 46: pressing device, 50: interposer body, 60: heating furnace, 100 , 200, 300, 400, 500 ... semiconductor devices.

Claims (11)

1. The melting point of the connection portion of the first member and the connection portion of the second member of the first member having the connection portion and the second member having the connection portion via a thermosetting adhesive Obtaining a temporary crimped body in which the connection portion of the first member and the connection portion of the second member are disposed to be opposed by pressure bonding at a temperature lower than the melting point;
   By holding the temporary pressure-bonded body between a pair of opposing pressing members, the temporary pressure-bonded body is heated to a temperature equal to or higher than the melting point of at least one of the connection of the first member and the connection of the second member. Obtaining a crimped body by applying pressure while
   Further heating the crimped body in a pressurized atmosphere;
   Equipped with
   A method of manufacturing a semiconductor device, wherein the first member is a semiconductor chip or a semiconductor wafer, and the second member is a printed circuit board, a semiconductor chip or a semiconductor wafer.
2. Partially curing the thermosetting adhesive in the step of obtaining the crimped body by applying heat and pressure to the temporary crimped body;
   The method according to claim 1, wherein the thermosetting adhesive is further cured in the step of heating the pressure-bonded body under a pressure atmosphere.
3. The method according to claim 2, wherein in the step of obtaining the pressure-bonded body by heating and pressurizing the temporary pressure-bonded body, the thermosetting adhesive is cured until a curing reaction rate becomes 30% or less. .
4. The method according to claim 2 or 3, wherein, in the step of heating the pressure-bonded body in a pressurized atmosphere, the curing reaction rate of the thermosetting adhesive is further cured to 85% or more.
5. The method according to any one of claims 1 to 4, wherein, in the step of heating the crimped body in a pressurized atmosphere, a plurality of the crimped bodies are heated at one time.
6. The method according to any one of claims 1 to 5, wherein a heating temperature in the step of heating the pressure-bonded body in a pressurized atmosphere is 130 ° C or more and 300 ° C or less.
7. The said thermosetting adhesive contains a thermosetting resin having a weight average molecular weight of less than 10000, a curing agent for the thermosetting resin, and a polymer component having a weight average molecular weight of 10000 or more. The method according to any one of 6.
8. The method according to any one of claims 1 to 7, wherein the minimum melt viscosity of the thermosetting adhesive is 3000 Pa · s or less.
9. A thermosetting adhesive for use in the method according to any one of the preceding claims, comprising:
   A thermosetting adhesive having a minimum melt viscosity of 3000 Pa · s or less.
10. The thermosetting adhesive according to claim 9, which is in the form of a film.
11. A first member having a connection portion, a second member having a connection portion, and an adhesive layer interposed therebetween, the connection portion of the first member and the connection portion of the second member And a semiconductor device electrically connected by metal bonding,
    The adhesive layer comprises a cured product of a thermosetting adhesive,
    The minimum melt viscosity of the thermosetting adhesive is 3000 Pa · s or less,
    The semiconductor device, wherein the first member is a semiconductor chip or a semiconductor wafer, and the second member is a wired circuit board, a semiconductor chip or a semiconductor wafer.

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