JP6405999B2 - Chip bonding apparatus and chip bonding method - Google Patents

Description

  The disclosed technology relates to a chip bonding apparatus and a chip bonding method.

  The following techniques are known for a chip bonding apparatus (chip bonder) used for flip chip mounting.

  For example, in an attachment used for a flip chip bonder that transfers heat and pressure to a semiconductor chip having protruding electrodes and joins the semiconductor chip to the substrate, the thermal conductivity of the central portion of the portion projected from the semiconductor chip is changed to the peripheral portion. The lower one is known.

  A thermocompression bonding head that has a crimping surface divided into a plurality of regions, presses the heat-bonded component while bringing the pressure-bonding surface into contact with the heat-bonded component, and a plurality of heaters that heat each region of the crimping surface. A thermocompression bonding tool including a temperature controller that controls each of the plurality of heaters is known.

  There is also known a bonding heater made of a ceramic base material including a heater portion in which a heating element is embedded and a holder portion that is integrally formed with the heater portion and fixes the heater portion. The heater portion has a groove provided along the outer periphery of the heater surface in the vicinity of the outer periphery of the heater surface. The opening of the groove is closed by a tool head mounted and fixed on the heater surface, and the inside of the groove becomes a closed space.

JP 2013-98264 A JP 2007-258483 A JP 2000-277567 A

  In flip chip mounting, a semiconductor chip is heated and pressed with a heated bonding tool to melt solder bumps provided on the bonding surface of the semiconductor chip and bond the semiconductor chip and the substrate.

  Since the heat flowing in the bonding tool is released to the outside from the outer peripheral portion of the bonding tool, the temperature of the outer peripheral portion of the bonding tool is lower than the temperature of the central portion. Thereby, the temperature of the outer peripheral portion of the semiconductor chip during bonding is lower than that of the central portion. The in-plane temperature difference of the semiconductor chip during bonding increases as the size of the semiconductor chip increases. When, for example, a 10 mm × 10 mm semiconductor chip is bonded using a conventional chip bonding apparatus, the temperature difference between the corner portion and the central portion of the semiconductor chip may be about 40 ° C. In the future, it is expected that the chip size will be further increased as the function of IC (integrated circuit) becomes higher, and thus the temperature difference in the chip surface at the time of bonding will be further increased.

When the temperature of the outer peripheral portion of the semiconductor chip is optimized with respect to the melting temperature of the solder bump during bonding, the temperature of the central portion of the semiconductor chip is significantly higher than the optimum temperature for melting the solder bump. An undesired compound (for example, Cu ₃ Sn) is abnormally formed on the solder bump in the center of the semiconductor chip to which excessive heat is applied during bonding, and reliability is lowered.

  In order to make the temperature in the semiconductor chip surface uniform during bonding, the above-described techniques have been proposed, but none of them is sufficient. For example, the in-plane temperature difference of a 10 mm × 10 mm semiconductor chip is 10%. It was difficult to keep the temperature below ℃.

  As an aspect, the disclosed technique aims to suppress an in-plane temperature difference of a semiconductor chip during bonding.

  The bonding apparatus according to the disclosed technology does not include a heat source in the center portion, includes a heat source in the outer peripheral portion, and has a heat generating surface that generates heat from the outer peripheral portion by the heat source, and is heated by the heat source from the heater portion. Includes bonding tools. The bonding tool has a first surface in which a central portion is directly or indirectly contacted with a central portion of the heat generating surface and an outer peripheral portion is directly or indirectly contacted with an outer peripheral portion of the heat generating surface. The bonding tool has a second surface that is provided on the side opposite to the first surface and contacts a bonding target during bonding. The bonding tool has a groove surrounding a central portion of the first surface.

  According to the disclosed technology, as one aspect, there is an effect that an in-plane temperature difference of the semiconductor chip during bonding can be suppressed.

It is a side view showing the composition of the chip bonding device concerning the embodiment of the art of an indication. It is a perspective view which shows the structure of the chip bonding apparatus which concerns on embodiment of the technique of an indication. It is a perspective view which shows the structure of the chip bonding apparatus which concerns on embodiment of the technique of an indication. It is a top view which shows the structure of the heat generating surface of the heater part which concerns on embodiment of the technique of an indication. It is a perspective view which shows the structure of the bonding tool which concerns on embodiment of the technique of an indication. FIG. 4 is a cross-sectional view taken along line 4-4 in FIG. 1B. It is a figure which shows the bonding method of the semiconductor chip using the chip bonding apparatus which concerns on embodiment of the technique of an indication. It is a figure which shows the bonding method of the semiconductor chip using the chip bonding apparatus which concerns on embodiment of the technique of an indication. It is sectional drawing which shows the flow of the heat | fever in the chip bonding apparatus which concerns on a 1st comparative example. It is sectional drawing which shows the flow of the heat | fever in the chip bonding apparatus which concerns on a 2nd comparative example. It is sectional drawing which shows the heat flow in the chip bonding apparatus which concerns on embodiment of the technique of an indication. It is a figure which shows the initial state of a solder bump when excessive heat is applied at the time of bonding. It is a figure which shows typically the initial state of a solder bump when appropriate heat is applied at the time of bonding. It is a figure which shows the state after the high temperature leaving test of a solder bump when excessive heat is applied at the time of bonding. It is a figure which shows the state after the high temperature leaving test of a solder bump when appropriate heat | fever is applied at the time of bonding. It is a figure which shows the result of having calculated | required the temperature distribution in the chip bonding apparatus which concerns on a 1st comparative example by simulation. It is a figure which shows the result of having calculated | required the temperature distribution in the chip bonding apparatus which concerns on a 2nd comparative example by simulation. It is a figure which shows the result of having calculated | required the temperature distribution in the chip bonding apparatus which concerns on embodiment of the technique of an indication by simulation. It is a perspective view which shows the structure of the chip bonding apparatus which concerns on 2nd Embodiment of the technique of an indication. It is sectional drawing which followed the 9B-9B line | wire in FIG. 9A. It is sectional drawing which shows the structure of the chip bonding apparatus which concerns on 3rd Embodiment of the technique of an indication. It is a top view which shows the structure of the refrigerant | coolant distribution part of the constant temperature mechanism which concerns on 3rd Embodiment of the technique of an indication. It is a top view which shows the structure of the heat generating surface of the heater part which concerns on 3rd Embodiment of the technique of an indication. It is sectional drawing which shows the structure of the chip bonding apparatus which concerns on 4th Embodiment of the technique of an indication. It is a top view which shows the structure of the heat generating surface of the heater part which concerns on 4th Embodiment of the technique of an indication. It is a top view which shows the other form of the groove | channel provided in the bonding tool which concerns on embodiment of the technique of an indication. It is a top view which shows the other form of the groove | channel provided in the bonding tool which concerns on embodiment of the technique of an indication. It is a side view showing other composition of a chip bonding device concerning an embodiment of an art of an indication. It is a top view which shows the structure of the cooling part which concerns on embodiment of the technique of an indication.

  Hereinafter, an exemplary embodiment of the disclosed technology will be described with reference to the drawings. In the drawings, the same or corresponding components and parts are denoted by the same reference numerals.

[First Embodiment]
FIG. 1A is a side view showing the configuration of the chip bonding apparatus 10 according to the first embodiment of the disclosed technique. The chip bonding apparatus 10 includes a heater unit 20 and a bonding tool 30. The chip bonding apparatus 10 may include a positioning mechanism (not shown) for the bonding tool 30 and a stage (not shown) on which a substrate or the like to be bonded to the semiconductor chip by the chip bonding apparatus 10 is placed. FIG. 1B is a perspective view of the chip bonding apparatus 10 viewed from the heater unit 20 side, and FIG. 1C is a perspective view of the chip bonding apparatus 10 viewed from the bonding tool 30 side. The heater unit 20 includes a heat source, having a heat generating surface S _h which generates heat by the heat source. In the present embodiment, the heater unit 20 has a rectangular parallelepiped, the outer shape of the heat generating surface S _h is a rectangle or square.

The bonding tool 30, the heater portion having a heat input surface S ₁ in contact with the heat generating surface S _h of 20, the chip contact surface S ₂ that is in contact with the semiconductor chip is bonded object on the opposite side of the heat input surface S ₁ Have The chip contact surface S ₂ of the bonding tool 30, the suction port 31 for holding a semiconductor chip which is the object of bonding to the chip contact surface S ₂ by vacuum suction is provided. The heater unit 20 heats the bonding tool 30 as the chip contact surface S ₂ has a predetermined temperature.

In the present embodiment, the bonding tool 30 has a first portion 30a having a heat input surface S ₁ disposed in the heater unit 20 side, the chip contact surface S ₂ which is arranged on the side opposite to the heater unit 20 And having a second portion 30b. In this embodiment, the heat input surface S ₁ is larger than the chip contact surface S _2. The bonding tool 30 may be made of a material mainly composed of, for example, SiC or AlN (thermal conductivity: 170 to 200 W / m · K) having a relatively high thermal conductivity.

Figure 2 is a plan view showing a configuration of a heat generating surface S _h of the heater unit 20 according to the first embodiment. Heat generating surface S _h of the heater unit 20 has nine areas specified by evenly divided into three heat generating surface S _h in the vertical and horizontal direction in FIG. 2. The heater unit 20 includes heat sources 21a to 21h in eight regions corresponding to the outer peripheral portion among the nine regions. The heat sources 21a to 21h can be controlled in temperature independently. For example, each of the heat sources 21a to 21h may be composed of a planar heating element such as an independent micro ceramic heater. In the present embodiment, the heat sources 21a, 21c, 21f, and 21h arranged at the corners of the heater unit 20 have higher set temperatures than the heat sources 21b, 21d, 21e, and 21g arranged between the corners. . That is, in the outer peripheral portion of the heat generating surface S _h, corner generates heat at a temperature higher than the portion other than the corner portion. In addition, you may make the preset temperature of the heat sources 21a-21h uniform.

  A heat insulating material 22 that suppresses heat conduction from the heat sources 21 a to 21 h is provided at the center of the heater unit 20. As the heat insulating material 22, for example, machinable ceramics (thermal conductivity: 1.4 to 8.6 W / m · K) or zirconia ceramics (thermal conductivity: 3.0 to 15.0 W / m · K) are preferably used. Can be used.

The bonding tool 30 has a central portion of the heat input surface S ₁ in contact with the heat insulating material 22 of the heater portion 20 and an outer peripheral portion of the heat input surface S ₁ in contact with the heat sources 21 a to 21 h of the heater portion 20. The heater unit 20 is connected. In other words, the central portion of the heat input surface S ₁ is in contact with the central portion of the heater portion 20, the outer peripheral portion of the heat input surface S ₁ is brought into contact with the outer circumference of the heater portion 20.

Figure 3 is a perspective view of the bonding tool 30 as viewed from the heat input surface S ₁ side. FIG. 4 is a cross-sectional view of the chip bonding apparatus 10 taken along line 4-4 in FIG. 1B. The bonding tool 30, the heat input surface _{S 1,} a rectangular annular groove 32 surrounding the central portion C of the heat input surface _{S 1.} As shown in FIG. 4, the groove 32 is preferably disposed on the inner side of the outer edge of the heat insulating material 22 disposed in the center of the heater unit 20. The depth of the groove 32, it is preferable that the distance is 50% or more of between heat input surface S ₁ and the chip contact surface S ₂ of the bonding tool 30.

  5A and 5B are diagrams illustrating an example of a semiconductor chip bonding method using the chip bonding apparatus 10 according to the present embodiment. As an example, a case where the semiconductor chip 100 is bonded to the substrate 110 is illustrated. .

  The semiconductor chip 100 has a plurality of solder bumps 101 provided on the bonding surface. A plurality of electrode pads 111 corresponding to each of the solder bumps 101 are provided on the bonding surface of the substrate 110.

  First, a thermosetting adhesive 120 is applied to the surface of the substrate 110 so as to cover the electrode pads 111. Thereafter, the substrate 110 is held on the stage 140 of the chip bonding apparatus 10.

The semiconductor chip 100 is picked up by the bonding tool 30 heated by the heater unit 20 and is held on the chip contact surface S ₂ of the bonding tool 30. The position of the bonding tool 30 is controlled by a positioning mechanism (not shown) of the chip bonding apparatus 10 so that the semiconductor chip 100 and the substrate 110 are aligned (FIG. 5A).

  Subsequently, the bonding tool 30 is lowered while holding the semiconductor chip 100 to bring the solder bump 101 into contact with the electrode pad 111 on the substrate 110. The bonding tool 30 applies heat and pressure to the semiconductor chip 100 while maintaining the state in which the solder bump 101 is in contact with the electrode pad 111. Thereby, the solder bump 101 is melted and the adhesive 120 is cured. Thereafter, the bonding tool 30 is lifted by releasing the holding of the semiconductor chip 100. The solder bumps 101 are solidified by natural cooling, and the bonding of the semiconductor chip 100 to the substrate 110 is completed.

FIG. 6A is a cross-sectional view of the chip bonding apparatus 10X according to the first comparative example. The cross section shown in FIG. 6A is a cross section corresponding to FIG. The chip bonding apparatus 10X according to the first comparative example includes a heater unit 20X and a bonding tool 30X. Heater unit 20X according to the first comparative example is not provided with a heat insulating structure corresponding to the heat insulating material 22 in which the heater unit 20 according to the present embodiment comprises the temperature of the heat generating surface S _h has a substantially uniform over the entire area It has become. Further, the bonding tool 30X according to the first comparative example does not include the groove 32 included in the bonding tool 30 according to the present embodiment.

In FIG. 6A, the heat flow in the bonding tool 30X is schematically shown. According to the chip bonding apparatus 10X according to the first comparative example, the heat supplied from the heater unit 20X to the bonding tool 30X is released to the outside from the outer peripheral portion of the bonding tool 30X, and is applied to the central portion of the bonding tool 30X. Accumulated. Thus, the temperature of the central portion of the chip contact surface S ₂ of the bonding tool 30X is higher than the temperature of the outer peripheral portion. That is, according to the chip bonding device 10X according to the first comparative example, the in-plane temperature difference tends to be large in the chip contact surface S ₂ of the bonding tool 30X. Thus, the semiconductor chip is in contact with the chip contact surface S ₂ at the time of bonding, the temperature of the central portion is higher than the temperature of the outer peripheral portion. When the temperature of the outer peripheral portion of the semiconductor chip is optimized with respect to the melting temperature of the solder bump during bonding, the temperature of the central portion of the semiconductor chip is significantly higher than the optimum temperature for melting the solder bump.

  FIG. 6B is a cross-sectional view of the chip bonding apparatus 10Y according to the second comparative example. The cross section shown in FIG. 6B is a cross section corresponding to FIG. The chip bonding apparatus 10Y according to the second comparative example includes the same heater unit 20 as the heater unit 20 according to the present embodiment, and the same bonding tool 30X as the bonding tool 30X according to the first comparative example.

In FIG. 6B, the heat flow in the bonding tool 30X is schematically shown. According to the chip bonding apparatus 10Y according to the second comparative example, since the heat insulating material 22 is provided in the central portion of the heater portion 20, the central portion of the heater portion 20 does not generate heat, and the heater portion 20 Heat conduction from the heat sources 21a to 21h provided on the outer peripheral portion to the central portion is also suppressed. Accordingly, the temperature of the central portion of the heat generating surface S _h of the heater unit 20 is lower than the temperature of the outer peripheral portion of the heat generating surface S _h. Accordingly, the bonding tool 30X is heated at a temperature at which the outer peripheral portion is higher than the central portion. That is, the amount of heat input at the center of the bonding tool 30X is suppressed. However, the heat supplied to the bonding tool 30X is released from the outer peripheral portion of the bonding tool 30X to the outside and is accumulated in the central portion of the bonding tool 30X. According to the chip bonding device 10Y according to the second comparative example will be smaller than with a chip bonding device 10X according plane temperature difference in the chip contact surface S ₂ of the bonding tool 30X to the first comparative example Can, but not enough.

Here, FIG. 7A is a diagram illustrating an initial state of the solder bump 101 when excessive heat is applied during bonding. FIG. 7B is a diagram schematically showing an initial state of the solder bump 101 when appropriate heat is applied during bonding. The solder bump 101 can be bonded to the semiconductor chip 100 via, for example, a Cu post 102. The solder bump 101 is, for example, SnAg solder, and the electrode pad 111 provided on the substrate 110 can be configured to include Cu. As apparent from comparison between FIG. 7A and FIG. 7B, when excessive heat is applied during bonding, a solder such as Cu ₃ Sn in the initial state is compared with the case where appropriate heat is applied. The amount of compound 130 produced is significantly increased.

  FIG. 7C is a diagram schematically illustrating a state after the high temperature storage test of the solder bump 101 when excessive heat is applied during bonding. FIG. 7D is a diagram schematically illustrating a state after the high temperature storage test of the solder bump 101 when appropriate heat is applied during bonding. Note that the high temperature storage test is a kind of accelerated test in a reliability test in which a thermal stress is applied to a test object to accelerate the progress of deterioration of the test object. 7C and FIG. 7D, when excessive heat is applied at the time of bonding, the growth of the solder compound 130 after the high-temperature standing test is compared with the case where appropriate heat is applied. Becomes more noticeable. As shown in FIG. 7C, when the proportion of the solder compound 130 occupying the solder bump 101 increases, the state becomes Sn poor and the Kirkendall void 131 is generated. Thereby, the resistance value in the said junction part may increase, or it may lead to a bump open.

According to the chip bonding device 10X and 10Y according to the first and second comparative examples, the bonding tool 30X chip contact surface S ₂ plane temperature difference sufficiently in (for example, 10 ° C. or less) is difficult to suppress Therefore, there is a possibility that a difference in bonding quality may occur between the outer peripheral portion and the central portion of the semiconductor chip.

FIG. 6C is a cross-sectional view of the chip bonding apparatus 10 according to the present embodiment. The cross section shown in FIG. 6C is a cross section corresponding to FIG. In FIG. 6C, the heat flow in the bonding tool 30 is schematically shown. According to the chip bonding apparatus 10 according to the present embodiment, since the heat insulating material 22 is provided in the central portion of the heater portion 20, the central portion of the heater portion 20 does not generate heat, and the outer periphery of the heater portion 20. Heat conduction from the heat sources 21a to 21h provided at the center to the center is also suppressed. Accordingly, the temperature of the central portion of the heat generating surface S _h is lower than the temperature of the outer peripheral portion. Therefore, the bonding tool 30 is heated at a temperature at which the outer peripheral portion is higher than the central portion. Further, an annular groove 32 formed on the heat input surface S ₁ of the bonding tool 30 is so exert a heat insulating effect, heat conduction is suppressed from the outer peripheral portion of the bonding tool 30 to the central portion.

As described above, according to the chip bonding apparatus 10 according to the present embodiment, the heat input at the central portion of the bonding tool 30 is suppressed by not disposing the heat source at the central portion of the heater portion 20. Furthermore, the heat transfer from the outer peripheral portion of the bonding tool 30 to the central portion is suppressed by the annular groove 32 provided in the bonding tool 30. Thus, it is possible to lower than the chip bonding device 10X and 10Y according to the temperature of the central portion of the chip contact surface S ₂ of the bonding tool 30 to the first and second comparative examples. As a result, it is possible to be smaller than chip bonding device 10X and 10Y according plane temperature difference in the chip contact surface S ₂ of the bonding tool 30 to the first and second comparative examples.

Furthermore, in the chip bonding apparatus 10 according to the present embodiment, the set temperatures of the heat sources 21a, 21c, 21f, and 21h arranged in the corner portion of the heater unit 20 are the heat sources 21b, 21d, and 21e arranged between the corner portions. And higher than the set temperature of 21 g. Accordingly, in the bonding tool 30, the corner portion is heated at the highest temperature, the portion other than the corner portion in the outer peripheral portion is heated at a temperature lower than the corner portion, and the central portion is heated at the lowest temperature. The bonding tool 30, since the highest heat radiation amount in the corner portion, the temperature setting of the plurality of heat sources 21a~21h the heater unit 20 In the manner described above, the bonding tool 30 chip contact surface plane in the S ₂ The temperature difference can be further reduced.

FIG. 8A and FIG. 8B are diagrams showing results obtained by simulating temperature distributions in the chip bonding apparatuses 10X and 10Y according to the first and second comparative examples, respectively. FIG. 8C is a diagram illustrating a result of a temperature distribution obtained by simulation in the chip bonding apparatus 10 according to the present embodiment. The FIGS. 8A, 8B and 8C, respectively, are shown temperature distribution along with a perspective view as viewed chip bonding device 10X, the 10Y and 10 from the chip contact surface _{S 2} side.

  The simulation conditions are as follows. Pro / Mechanica was used as an analysis tool for the temperature distribution of the chip bonding apparatuses 10X, 10Y and 10. Assuming that SiC is used as the material of the heater parts 20 and 20X and the bonding tools 30 and 30X excluding the heat insulating material 22, the specific heat is 0.67 J / g · K, and the thermal conductivity is 200 W / m · K. It was. Assuming that machinable ceramics is used as the heat insulating material 22 of the heater section 20, the specific heat of the heat insulating material 22 is set to 0.19 J / g · K, and the thermal conductivity is set to 1.7 W / m · K.

Heater unit 20 and 20X are the size of the heat generating surface _{S h} and 30 mm × 30 mm, and a thickness of 4 mm. In the heater unit 20, the size of each of the nine divided regions (see FIG. 2) is 10 mm × 10 mm. In the bonding tools 30 and 30X, the size of the heat input surface S1 of the _first portions 30a and 30Xa was 24 mm × 24 mm, and the thickness was 2 mm. Further, the size of the chip contact surface S2 of the _second portions 30b and 30Xb was 16 mm × 16 mm, and the thickness was 6 mm.

The thermal load of the heater section 20X according to the first comparative example was set to 2.2 × 10 ⁹ mW. The thermal loads of the heat sources 21a, 21c, 21f, and 21h arranged at the corners of the heater unit 20 according to the second comparative example were 1.4 × 10 ⁹ mW, respectively. The thermal load of the heat sources 21a, 21c, 21f, and 21h arranged in the corner portion of the heater unit 20 according to the present embodiment was 1.45 × 10 ⁹ mW. Moreover, the thermal load of the heat sources 21b, 21d, 21e, and 21g according to the second comparative example and this embodiment was set to 1.0 × 10 ⁵ mW. Setting of the thermal load in the heater unit 20 and 20X is a condition for setting the temperature of the central portion of the chip contact surface S ₂ of the bonding tool 30 and 30X substantially 300 ° C.. Further, the atmospheric temperature was set to 30 ° C., and the heat transfer coefficient between the chip bonding apparatuses 10, 10X, and 10Y and the atmosphere was set to 2.85 W / (m ² · K).

As shown in FIG. 8A, the chip bonding device 10X according to the first comparative example, the temperature of the point A is the center part of the chip contact surface S ₂ is 299.1 ° C., B point is the corner portion And the temperature at point C were 274.4 ° C. and 275.3 ° C., respectively. That is, the in-plane temperature difference in the chip contact surface S ₂ of the chip bonding device 10X according to the first comparative example was 24.7 ° C..

As shown in FIG. 8B, the chip bonding device 10Y according to the second comparative example, the temperature of the point A is the center part of the chip contact surface S ₂ is 303.0 ° C., B point is the corner portion And C point temperatures were 283.4 ° C. and 282.4 ° C., respectively. That is, the in-plane temperature difference in the chip contact surface S ₂ of the chip bonding device 10Y according to the second comparative example was 20.6 ° C..

As shown in FIG. 8C, in the chip bonding apparatus 10 according to the present embodiment, the temperature of the point A is the center part of the chip contact surface S ₂ is 300.2 ° C., B point is the corner portion and C The point temperatures were 291.5 ° C. and 291.1 ° C., respectively. That is, the in-plane temperature difference in the chip contact surface S ₂ of the chip bonding apparatus 10 of this embodiment was 9.1 ° C.. Thus, according to the chip bonding apparatus 10 according to the present embodiment, in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30 a can be a 10 ° C. or less. That is, according to the chip bonding apparatus 10 according to the present embodiment, could be significantly smaller than the chip bonding device 10X and 10Y according plane temperature difference in the chip contact surface S ₂ in the first and second comparative examples .

As described above, according to the chip bonding apparatus 10 according to the present embodiment, the amount of heat input at the central portion of the bonding tool 30 is suppressed by not disposing the heat source at the central portion of the heater portion 20. Furthermore, the heat transfer from the outer peripheral portion of the bonding tool 30 to the central portion is suppressed by the annular groove 32 provided in the bonding tool 30. Thus, it is possible to suppress the in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30, it is possible to suppress the in-plane temperature difference of the semiconductor chip at the time of bonding. Thereby, in flip chip mounting, it is possible to prevent a difference in bonding quality between the outer peripheral portion and the central portion of the semiconductor chip.

[Second Embodiment]
FIG. 9A is a perspective view illustrating a configuration of a chip bonding apparatus 10A according to the second embodiment of the disclosed technique. 9B is a cross-sectional view taken along line 9B-9B in FIG. 9A. A chip bonding apparatus 10A according to the second embodiment includes a heater unit 20A having a configuration different from that of the heater unit 20 according to the first embodiment. The configuration of the bonding tool 30 in the chip bonding apparatus 10A according to the second comparative example is the same as that of the bonding tool 30 of the first embodiment.

  20 A of heater parts which concern on 2nd Embodiment have the some heat source 21a-21h which can respectively independently temperature-control on the outer peripheral part similarly to the heater part 20 which concerns on 1st Embodiment. The heater part 20A according to the second embodiment is provided with a hollow part 23 in the center part. That is, the heater section 20A according to the second embodiment has a configuration in which the heat insulating material 22 in the heater section 20 according to the first embodiment is replaced with the cavity section 23.

The bonding tool 30 includes a central portion of the heat input surface _{S 1} is being placed in the formation position of the cavity 23 in the heater unit 20, the outer peripheral portion of the heat input surface _{S 1} is in contact with the heat source 21a~21h heater portion 20A As shown in FIG. Grooves 32 provided on the heat input surface S ₁ of the bonding tool 30 is preferably disposed inside the outer edge of the cavity 23 arranged in the central portion of the heater unit 20.

According to the chip bonding device 10A according to the second embodiment, similarly to the chip bonding apparatus 10 according to the first embodiment, it is possible to suppress the in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30 It is. As a result, it is possible to suppress the in-plane temperature difference of the semiconductor chip during bonding, so that it is possible to prevent a difference in bonding quality between the outer peripheral portion and the central portion of the semiconductor chip in flip chip mounting. be able to.

Furthermore, according to the chip bonding apparatus 10A according to the second embodiment, since the central portion of the heater portion 20A is hollow, the heater portion according to the first embodiment having the heat insulating material 22 at the central portion of the heater portion 20. Compared with 20, the heat insulation in the center part of a heater part can be improved. Thereby, the effect which suppresses the heat gain in the center part of the bonding tool 30 can be heightened rather than the chip bonding apparatus 10 which concerns on 1st Embodiment. Therefore, the in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30, it is possible to be smaller than the chip bonding apparatus 10 according to the first embodiment.

[Third Embodiment]
FIG. 10A is a cross-sectional view illustrating a configuration of a chip bonding apparatus 10B according to a third embodiment of the disclosed technique. The cross section shown in FIG. 10A is a cross section corresponding to FIG. Chip bonding apparatus 10B according to the third embodiment, the incubation mechanism 40 to maintain the temperature of the central portion of the heat generating surface S _h of the heater portion 20B, a substantially constant temperature lower than the temperature of the outer peripheral portion of the heat generating surface S _h Have.

  The constant temperature mechanism 40 has a circulation flow path 42 for circulating a refrigerant made of liquid or gas inside, and is connected to the refrigerant flow portion 40a and the refrigerant flow portion 40a that are spaced apart from the heater portion 20B. And a protruding portion 40b fitted in the central portion of the heater portion 20B. The refrigerant circulation part 40a and the protruding part 40b of the constant temperature mechanism 40 can be made of a metal such as Al having a relatively high thermal conductivity, for example.

FIG. 10B is a plan view showing an example of the configuration of the refrigerant circulation part 40a of the constant temperature mechanism 40. The refrigerant circulation part 40a has a refrigerant circulation channel 42 therein. The circulation channel 42 is provided so as to meander inside the refrigerant circulation part 40a. One end of the circulation channel 42 is connected to the refrigerant inlet 43, and the other end of the circulation channel 42 is connected to the refrigerant outlet 44. The refrigerant that has flowed out of the outlet 44 is cooled by a heat exchanger (not shown) and then flows into the inlet 43 again. The refrigerant flowing through the circulation channel 42 is controlled so as to always have a constant temperature. By circulating a refrigerant in a constant temperature in the circulation flow path 42, the temperature of the end face S _t of the projecting portion 40b is maintained substantially constant.

Figure 11 is a plan view showing a configuration of a heat generating surface S _h of the heater portion 20B according to the third embodiment. Similarly to the heater unit 20 according to the first embodiment, the heater unit 20B according to the third embodiment includes a plurality of heat sources 21a to 21h that can be independently controlled in temperature on the outer periphery. The central portion of the heater portion 20B is a cavity, and the protruding portion 40b of the thermostatic mechanism 40 is fitted into this cavity. End surface S _t of the projecting portion 40b extends to the heat generating surface S _h and the same plane. Accordingly, the temperature of the central portion of the heat generating surface S _h is substantially maintained at a constant temperature lower than the temperature of the outer peripheral portion of the heat generating surface S _h.

The configuration of the bonding tool 30 in the third chip bonding apparatus 10B is the same as that of the bonding tool 30 according to the first embodiment. The bonding tool 30, as the central portion of the heat input surface _{S 1} is in contact with the projecting portion 40b of the incubation mechanism 40, the outer peripheral portion of the heat input surface _{S 1} is brought into contact with the heat source 21a~21h heater portion 20B It is connected to the heater part 20B. Grooves 32 provided on the heat input surface S ₁ of the bonding tool 30 is preferably disposed inside the outer edge of the projecting portion 40b of the incubation mechanism 40 disposed in a central portion of the heater unit 20.

According to the chip bonding apparatus 10B according to the third embodiment, similarly to the chip bonding apparatus 10 according to the first embodiment, it is possible to suppress the in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30 It is. As a result, it is possible to suppress the in-plane temperature difference of the semiconductor chip during bonding, so that it is possible to prevent a difference in bonding quality between the outer peripheral portion and the central portion of the semiconductor chip in flip chip mounting. be able to.

Furthermore, according to the chip bonding apparatus 10B according to the third embodiment, the temperature of the central portion of the heat generating surface S _h of the heater portion 20B, controlled substantially constant temperature lower than the temperature of the outer peripheral portion of the heat generating surface S _h Is possible. Thereby, the effect which suppresses the heat gain in the center part of the bonding tool 30 can be heightened rather than the chip bonding apparatus 10 which concerns on 1st Embodiment. Therefore, the in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30, it is possible to be smaller than the chip bonding apparatus 10 according to the first embodiment.

[Fourth Embodiment]
FIG. 12A is a cross-sectional view illustrating a configuration of a chip bonding apparatus 10C according to a fourth embodiment of the disclosed technique. The cross section shown in FIG. 12A is a cross section corresponding to FIG. A chip bonding apparatus 10C according to the fourth embodiment includes a heater unit 20C having a configuration different from that of the heater unit 20 according to the first embodiment. The configuration of the bonding tool 30 in the chip bonding apparatus 10C according to the third embodiment is the same as that of the chip bonding apparatus 10 according to the first embodiment.

Figure 12B is a plan view showing a configuration of a heat generating surface S _h of the heater unit 20C according to the fourth embodiment. Heat generating surface S _h of the heater portion 20C has nine areas specified by evenly divided into three heat generating surface S _h in the vertical and horizontal direction in FIG. 12B. The heater unit 20C includes heat sources 21a, 21c, 21f, and 21h in four regions corresponding to the corner portion among the nine regions. The heat sources 21a, 21c, 21f, and 21h can be independently controlled in temperature.

  The heater portion 20C is a portion other than the corner portion in the outer peripheral portion, that is, between the heat sources 21a and 21c, between the heat sources 21a and 21f, between the heat sources 21c and 21h, and between the heat sources 21f and 21h, respectively. It has the heat conductive member 24 which has heat conductivity. The heat conducting member 24 is heated by the heat sources 21a, 21c, 21f, and 21h arranged at each corner portion of the heater portion 20C.

  A heat insulating material 22 that suppresses heat conduction from the heat sources 21a, 21c, 21f, and 21h and the heat conducting member 24 is provided at the center of the heater portion 20C. As described above, the heater section 20C according to the fourth embodiment has a configuration in which the heat sources 21b, 21d, 21e, and 21g in the heater section 20 according to the first embodiment are replaced with the heat conducting member 24.

In the bonding tool 30, the center part of the heat input surface S ₁ is in contact with the heat insulating material 22, and the outer peripheral part of the heat input surface S ₁ is in contact with the heat sources 21 b, 21 d, 21 e, 21 g and the heat conduction member 24. Are connected to the heater section 20C.

According to the chip bonding apparatus 10C, the temperature of the central portion of the heat generating surface S _h of the heater unit 20C is lower than the temperature of the outer peripheral portion of the heat generating surface S _h. The heat conduction member 24, so itself does not generate heat, the outer peripheral portion of the heat generating surface S _h of the heater portion 20C, the temperature of the corner portion is higher than the temperature of a portion other than the corner portion. That is, according to the chip bonding device 10C, the heat generating surface S _h of the heater portion 20C, it is possible to form a similar temperature distribution in the case of the first embodiment. Thereby, as for the bonding tool 30, a corner part is heated at the highest temperature, parts other than a corner part in an outer peripheral part are heated at a temperature lower than a corner part, and a center part is heated at the lowest temperature. By adjusting the thermal conductivity of the heat conductive member 24, i.e., by appropriately selecting the material of the heat conducting member 24, it can form a desired temperature distribution in the heat generating surface S _h of the heater portion 20C It is. Examples of candidate materials for the heat conductive member 24 include alumina ceramics (thermal conductivity: 30 to 35 W / m · K), carbon steel (thermal conductivity: 40 to 85 W / m · K), and the like.

According to the chip bonding apparatus 10C according to the fourth embodiment, similarly to the chip bonding apparatus 10 according to the first embodiment, it is possible to suppress the in-plane temperature difference in the chip contact surface S ₂ of the bonding tool 30 It is. As a result, it is possible to suppress the in-plane temperature difference of the semiconductor chip during bonding, so that it is possible to prevent a difference in bonding quality between the outer peripheral portion and the central portion of the semiconductor chip in flip chip mounting. be able to.

Furthermore, according to the chip bonding apparatus 10C according to the fourth embodiment, the temperature distribution in the heat generating surface S _h of the heater portion 20C can be adjusted by the thermal conductivity of the heat conducting member 24. Thereby, compared with the 1st-3rd embodiment, the number of the heat sources in a heater part can be reduced, and it becomes possible to aim at the power saving of a chip bonding apparatus.

In each of the above embodiments, a case has been exemplified that the shape of the groove 32 provided in the heat input surface S ₁ of the bonding tool 30 and rectangular ring, it is not limited thereto, the bonding tool 30 Any form may be used as long as it surrounds the central portion C. 13A and 13B are diagrams showing variations in the form of a groove provided on the heat input surface S ₁ of the bonding tool 30. As shown in FIG. 13A, a groove 32 provided in the heat input surface S ₁ of the bonding tool 30 may have a circular ring shape. Further, as shown in FIG. 13B, a plurality of linear grooves 32a, 32b, 32c and 32d may be provided so as to surround the center portion C of the heat input surface _{S 1} of the bonding tool 30.

Further, in the above embodiments, bonding heat input surface S ₁ of the tool 30, has been illustrated directly connected to each the heat generating surface S _h of the heater unit, the heat input surface of the bonding tool 30 S ₁ and the heater unit heat conductive member or the like may be interposed between the heat generating surface S _h. That is, the bonding tool 30, the heater portion 20, 20A, 20B, or may be indirectly contact the heating surface _{S h} of 20C.

Moreover, in each said embodiment, although the structure which has arrange | positioned the several heat source which can control temperature independently in the outer peripheral part of the heater parts 20, 20A, 20B, 20C was illustrated, it is not limited to this aspect. . In the outer peripheral portion of the heat generating surface S _h of the heater unit, in the case without the temperature difference between the corner portion and other portions, the heater unit, a single to be exothermic integrally with the outer peripheral portion of the heat generating surface S _h You may have a heat source.

Further, in the above embodiments, a case has been exemplified that divides the heat generating surface S _h of the heater section into nine areas, but is not limited to this embodiment. Heat generating surface S _h of the heater unit may have at least two regions having no central portion of the outer peripheral portion and a heat source having a heat source. Further, the number of divisions of the regions of the heat generating surface S _h is larger than 9, the may be provided each of the divided regions the heat source whose temperature can be controlled independently for each.

  Further, the heat conducting member 24 according to the fourth embodiment may be applied to the heater part 20A according to the second embodiment and the heater part 20B according to the third embodiment.

Further, as shown in FIG. 14A, first, second and fourth embodiments in accordance chip bonding device 10, 10A, 10C, the surface opposite to the heat generating surface _{S h} of the heater portion 20, 20A, 20C The cooling unit 50 may be provided. The cooling unit 50 is interposed between other components of the chip bonding apparatus disposed above the heater units 20, 20 </ b> A, and 20 </ b> C, thereby transferring heat from the heater unit to the other components. Cut off.

  FIG. 14B is a diagram illustrating a configuration of the cooling unit 50. The cooling unit 50 has a circulation channel 51 for circulating a refrigerant made of liquid or gas inside. One end of the circulation channel 51 is connected to the refrigerant inlet 52, and the other end of the circulation channel 51 is connected to the refrigerant outlet 53. By circulating the refrigerant through the circulation channel 51, the cooling unit 50 exhibits a heat insulating function. In the chip bonding apparatus 10 </ b> B (see FIG. 10A) according to the third embodiment, the constant temperature mechanism 40 also plays the same role as the cooling unit 50.

Note that the chip bonding apparatuses 10, 10A, 10B, and 10C are examples of the chip bonding apparatus in the disclosed technology. The heater units 20, 20A, 20B, and 20C are examples of the heater unit in the disclosed technology. The heat generating surface _Sh is an example of a heat generating surface in the disclosed technology. The bonding tool 30 is an example of a bonding tool in the disclosed technology. Heat input surface S ₁ of the bonding tool 30 is an example of the first surface in the disclosed technique. Chip contact surface S ₂ of the bonding tool 30 is an example of the second surface in the disclosed technique. The groove 32 is an example of the groove in the disclosed technology. The heat insulating material 22 is an example of a heat insulating material in the disclosed technology. The cavity 23 is an example of a cavity in the disclosed technology. The constant temperature mechanism 40 is an example of a constant temperature mechanism in the disclosed technology. The heat conducting member 24 is an example of a heat conducting member in the disclosed technology.

  Regarding the above first and second embodiments, the following additional notes are disclosed.

(Appendix 1)
A heater part having no heat source in the central part, a heat source in the outer peripheral part, and a heat generating surface in which the outer peripheral part generates heat by the heat source;
The first surface, the first surface of which the central portion is in direct or indirect contact with the central portion of the heat generating surface and the outer peripheral portion is in direct or indirect contact with the outer peripheral portion of the heat generating surface. A bonding tool having a second surface provided on the opposite side and in contact with a bonding target during bonding, and a groove surrounding the central portion of the first surface provided on the first surface;
A chip bonding apparatus including:

(Appendix 2)
The chip bonding apparatus according to claim 1, wherein the heater unit includes a plurality of heat sources capable of independently controlling temperature.

(Appendix 3)
The chip bonding apparatus according to claim 2, wherein the heat generating surface has a rectangular shape, and each corner portion generates heat at a higher temperature than a portion other than the corner portion at an outer peripheral portion of the heat generating surface.

(Appendix 4)
The chip bonding apparatus according to any one of appendix 1 to appendix 3, wherein the heater unit includes a heat insulating material that suppresses heat conduction from the heat source at a central portion.

(Appendix 5)
The chip bonding apparatus according to any one of appendix 1 to appendix 3, wherein the heater portion has a hollow portion in a central portion.

(Appendix 6)
The chip bonding apparatus according to any one of appendix 1 to appendix 3, further including a thermostatic mechanism that maintains a temperature of a central portion of the heat generating surface at a temperature lower than a temperature of an outer peripheral portion of the heat generating surface.

(Appendix 7)
The chip bonding apparatus according to any one of appendix 1 to appendix 6, wherein the heater unit includes a heat conducting member that is heated by the heat source at an outer peripheral portion.

(Appendix 8)
The chip bonding apparatus according to claim 7, wherein the heat conducting member is disposed in a portion other than the corner portion of the heater portion.

(Appendix 9)
The chip bonding apparatus according to any one of Appendix 1 to Appendix 8, wherein the heater unit includes a plurality of planar heaters as the heat source.

(Appendix 10)
The chip bonding apparatus according to any one of appendix 1 to appendix 9, wherein the depth of the groove is 50% or more of the distance between the first surface and the second surface.

(Appendix 11)
The chip bonding apparatus according to claim 4, wherein the groove is provided on an inner side than an outer edge of the heat insulating material.

(Appendix 12)
The chip bonding apparatus according to claim 5, wherein the groove is provided on an inner side than an outer edge of the cavity.

(Appendix 13)
The chip bonding apparatus according to claim 6, wherein the groove is provided inside an outer edge of a portion extending to the heat generating surface of the constant temperature mechanism.

(Appendix 14)
A heater part having no heat source in the central part, a heat source in the outer peripheral part, and a heat generating surface in which the outer peripheral part generates heat by the heat source;
The first surface, the first surface of which the central portion is in direct or indirect contact with the central portion of the heat generating surface and the outer peripheral portion is in direct or indirect contact with the outer peripheral portion of the heat generating surface. A bonding tool having a second surface provided on the opposite side and in contact with a bonding target during bonding, and a groove surrounding the central portion of the first surface provided on the first surface;
A chip bonding method for bonding the semiconductor chip to a substrate by bringing the second surface of the chip bonding apparatus including the semiconductor chip into contact with the semiconductor chip to be bonded and applying heat from the heat source to the semiconductor chip.

(Appendix 15)
The chip bonding method according to claim 14, wherein the heat generating surface has a rectangular shape, and each corner portion generates heat at a higher temperature than a portion other than the corner portion at an outer peripheral portion of the heat generating surface.

10, 10A, 10B, 10C chip bonding device 20, 20A, 20B, 20C heater unit 21a~21h heat source 22 heat insulating material 23 cavity 24 heat conducting member 30 bonding tool 32 groove 40 incubation mechanism 100 semiconductor chip 110 substrate _{S h} heating surface S ₁ heat input surface S ₂ chip contact surface

Claims (9)

A heater part having no heat source in the central part, a heat source in the outer peripheral part, and a heat generating surface in which the outer peripheral part generates heat by the heat source;
The first surface, the first surface of which the central portion is in direct or indirect contact with the central portion of the heat generating surface and the outer peripheral portion is in direct or indirect contact with the outer peripheral portion of the heat generating surface. A bonding tool having a second surface provided on the opposite side and in contact with a bonding target during bonding, and a groove surrounding the central portion of the first surface provided on the first surface;
A chip bonding apparatus including: The chip bonding apparatus according to claim 1, wherein the heater unit includes a plurality of heat sources capable of independently controlling temperature. The chip bonding apparatus according to claim 2, wherein the heat generating surface has a rectangular shape, and each corner portion generates heat at a temperature higher than that of a portion other than the corner portion in an outer peripheral portion of the heat generating surface. The chip bonding apparatus according to any one of claims 1 to 3, wherein the heater unit includes a heat insulating material that suppresses heat conduction from the heat source at a central portion. The chip bonding apparatus according to claim 1, wherein the heater portion has a hollow portion at a central portion. The chip bonding apparatus according to any one of claims 1 to 3, further comprising a thermostatic mechanism that maintains a temperature of a central portion of the heat generating surface at a temperature lower than a temperature of an outer peripheral portion of the heat generating surface. The chip bonding apparatus according to claim 1, wherein the heater unit includes a heat conductive member that is heated by the heat source at an outer peripheral part. The chip bonding apparatus according to claim 7, wherein the heat conducting member is disposed in a portion other than the corner portion of the heater portion. A heater part having no heat source in the central part, a heat source in the outer peripheral part, and a heat generating surface in which the outer peripheral part generates heat by the heat source;
The first surface, the first surface of which the central portion is in direct or indirect contact with the central portion of the heat generating surface and the outer peripheral portion is in direct or indirect contact with the outer peripheral portion of the heat generating surface. A bonding tool having a second surface provided on the opposite side and in contact with a bonding target at the time of bonding, and a groove surrounding the center of the first surface provided on the first surface;
A chip bonding method for bonding the semiconductor chip to a substrate by bringing the second surface of the chip bonding apparatus including the semiconductor chip into contact with the semiconductor chip to be bonded and applying heat from the heat source to the semiconductor chip.