JP3053153U - Solder fusion equipment - Google Patents

Abstract

(57) Abstract: In a manufacturing process of a composite semiconductor module or the like, in a solder fusing apparatus for fixing a component such as an insulating substrate and a semiconductor chip to a base substrate such as a metal for heat dissipation by melting and fixing a solder. And means for minimizing the voids of the solder interposed in the solder and minimizing the scattering and outflow of the solder out of the fixed portion. SOLUTION: A heating unit such as a hot plate, which is composed of heaters divided and arranged in a lattice, and an opening / closing opening arranged in a lattice in the upper part of the heating unit, and a lifting / lowering operation and adjustment of a cooling amount are possible. And a control unit that controls the heating temperature of the heater and the opening / closing operation of the opening / closing port of the cool air outlet unit to generate a three-dimensional temperature gradient, thereby obtaining a good solder fusion state. .

Description

[Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention relates to a soldering apparatus for melting and fixing a component such as a semiconductor chip to a base substrate such as a metal for heat dissipation in a manufacturing process of a composite semiconductor module or the like.

[0002]

[Prior art]

 Conventionally, there is an apparatus of this type shown in FIG. In the figure, 8 is a heating device such as a hot plate, 9 is a temperature adjusting means for adjusting the surface temperature of the heating device, 5 is a base substrate such as a metal for heat dissipation, 7 is a component such as a semiconductor chip, 6 Is a solder such as a cream solder loaded between the base substrate 5 such as a metal and the component 7.

A solder 6 is loaded at a predetermined bonding position of a base substrate 5 such as a metal, a component 7 is mounted at the position, and then mounted on the heating device 8. At this time, the entire surface of the heating device 8 is preheated uniformly and at a preset temperature, for example, near the melting point temperature of the solder. The temperature is controlled by the temperature adjusting means 9 until the temperature reaches or exceeds the melting temperature of the solder.

[0004] After the solder starts to melt and melts in the above temperature range for a predetermined time, the surface temperature of the heating device 8 is lowered or natural cooling is performed by introducing outside air to complete the fusion.

[0005]

[Problems to be solved by the invention]

 As described above, in the conventional apparatus, in order to control the surface of a heating device such as a hot plate so that the entire surface is uniform at a predetermined set temperature, the temperature is set subdivided for each part or for each part of the part, and Temperature control is difficult.

According to the above-described structure, in the process of fixing the components to each other by melting and cooling the solder, bubbles and nests (hereinafter, referred to as voids) of the solder which may originally occur due to thermal or mechanical factors. It is extremely difficult to take compensatory measures to control the occurrence. Therefore, there is a defect that the quality is remarkably deteriorated, for example, a void of the solder remains between the components, the solder is easily scattered and flows out of the fixed portion, and a solder joining defect is caused.

Further, when a plurality of components having different heat resistance characteristics or different amounts of solder to be loaded into a joint are simultaneously placed and fused on the same heating device surface, the melting temperature, melting time, cooling, etc. Since the fixing condition cannot be controlled, the same problem as described above occurs. In addition, some parts may cause thermal destruction, resulting in extremely low reliability.

[0010] Furthermore, in a case where base substrates made of metal or the like having different heat capacities are mixed and fused on the same heating device surface, it is difficult to individually set and adjust the temperature. However, there is a disadvantage that the yield increases significantly.

[0009]

[Means to solve the problem]

 The present invention has been made in order to eliminate the disadvantages of the above-mentioned conventional apparatus, and based on a predetermined soldering temperature profile, the heating temperature of the heater divided in the grid and the heating temperature are arranged in the grid. By controlling the opening / closing operation and the cooling amount of the cool air ejection portion having the opening / closing port in conjunction, a subdivided three-dimensional temperature gradient is generated on the heating portion surface.

[0010]

[Action]

 By determining the melting start point of the solder and the direction of spread of the molten surface that chain-expands with the component, and by providing fixing means for sequentially melting and cooling the solder with a predetermined time difference, the solder generated between the components can be formed. In addition to suppressing voids, the solder is prevented from scattering and flowing out of the fixed part.

[0011] Furthermore, when simultaneously soldering a plurality of different types of components on the heating unit, a soldering temperature profile corresponding to the type of base substrate such as a metal or a component and the amount of solder at the joint is used. By setting, the same effect as described above is obtained, and efficient solder fusion is realized with reduced work such as setup change.

[0012]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the first embodiment, FIG. 1, the heating unit 1 includes a plurality of heaters 11 such as a plurality of square heaters divided in a grid as shown in the sectional structural views of FIGS. 2 (A1) and 2 (A2). As shown in FIGS. 2 (B1) and 2 (B2), the cool air blowout portion 2 is an electronic cooling fan having shutter-shaped opening / closing ports 12 arranged in a grid.

In a pre-process, a solder 6 is loaded at a predetermined bonding position of a base substrate 5 such as a metal, a component 7 such as a semiconductor chip is mounted at the position, and then placed on the surface of the heating unit 1 under a predetermined condition. Perform solder fusion. At this time, the components 7 on the base substrate 5 often have different shapes and heat-resistant characteristics, and the amount of solder 6 at the joint varies.

Therefore, after the surface temperature of the normal heating unit 1 starts to rise from the preheating temperature and the cooling is completed after the solder 6 reaches the melting temperature or higher, the time required for the components on the base substrate 5, Since it differs depending on the mounting position on the heating unit 1 surface, it can be easily supposed that a difference occurs in the fusion result depending on the component 7.

In this embodiment, the automatic temperature setting control unit 3 first sets the heating unit 1 surface according to the type of the base substrate 5 such as a metal, the shape of a component 7 such as a semiconductor chip, and the amount of solder 6 at the joint. A series of temperature control curves from the above preheating (K1) to melting (K2) and cooling (K3) steps, that is, a solder fusion temperature profile is created.

Then, based on the fusion temperature profile, the temperature of the heating unit 1 and the opening / closing port 12 of the cold air ejection unit 2 are controlled. Here, the cool air ejection part 2 has an almost one-to-one opposing positional relationship with the upper part of the heating part 1 so that the lifting operation (4) and the cooling amount can be adjusted.

The temperature of the heaters 11 divided and arranged in a grid is individually controlled, and the amount of cooling of the cold air jetting unit 2 and the opening or closing operation of the opening / closing port 12 are linked with each other, so that the heating unit 1 A three-dimensional (X, Y, Z) temperature gradient obtained by combining the heating operation and the cooling operation on the surface is obtained.

Accordingly, even when a plurality of base substrates 5 made of metal or the like having different thermal conductivities are used at the same time, or when the heat resistance of the component 7 to be mounted and the amount of solder 6 at the joint part are different, the heating unit 1 The fixing conditions such as the melting temperature and the melting time of the solder can be set freely for each of the base substrate 5 and the component 7, so that the suitable solder fusion can be performed while suppressing the voids and scattering of the solder.

Usually, the heat capacity of the base substrate 5 such as a metal, the heat resistance of the component 7 to be mounted, the melting point temperature of the solder 6, and the like can be quantified or known in many cases, and the fusion temperature profile is easily created. it can.

Here, the fusion temperature profile will be described with reference to FIGS. 3A and 3B. For ease of explanation, the fusion temperature profile (P1) when the shape of the component 7 and the amount of solder 6 at the joint is considered to be a standard (E1) is shown and compared with this.

When the area of the joint and the thickness of the solder 6 to be loaded are increased in accordance with the shape of the component 7 (E2), the fusion temperature profile (P2) indicates that the surface temperature of the heating unit 1 is higher than normal. Set higher and set the melting time slightly longer. In addition, a gradual heating curve shall be drawn to prevent thermal damage to components and the occurrence of solder balls, solder bridges, etc. due to rapid temperature rise.

In the case (E3) of using a base substrate 5 made of metal or the like whose heat capacity increases due to the material, plate thickness, etc., the surface temperature of the heating unit 1 needs to be set high, so that the temperature rises quickly from the preheating state. Is started so that the temperature can reach the melting temperature of the solder or more within a predetermined time. Further, as a means for suppressing a rise in temperature and a heat accumulation due to a delay in heat conduction, a fusion temperature profile (P3) for properly operating the cold air jetting section 2 and forcibly cooling is set.

The second embodiment and the present embodiment are the same as those of the first embodiment, except that the melting start point of the solder and the spreading direction of the melting surface which is chained with the melting point are determined for each of the parts 7 and the predetermined direction is determined. In order to obtain means for sequentially melting and cooling the solder by providing a time difference of the following, the number of divisions and the division position of the heater 11 and the cool air jet opening / closing port 12 are added to the part 7 and the solder 6 of the joint surface. The correlated three-dimensional coordinates (X, Y, Z) as shown in FIG.

The automatic temperature setting control unit 3 calculates a melting start point (X0, Y0, Z) and a predetermined melting time difference (T1, T2, TN) on the three-dimensional coordinates (X, Y, Z). A cooling time difference is set, and a continuous direction (D) is provided in the order of (X1, Y0, Z), (X0, Y1, Z), (XN, YN, Z), and the heating temperature and the cooling are sequentially set. Adjust the amount and fuse. The fusion temperature profile (P4) shown in FIG. 4B describes the above-described series of operation processes.

In the continuous fixing process such as melting and cooling of the solder, the solder stays in the solder 6 or the voids of the solder interposed between the components 7 are easily pushed out to the outside in a stepwise manner. And the flow out is suppressed, so the reliability at the time of fusion is greatly enhanced.

[0026]

[Effect of the invention]

 As described above, according to the present invention, in the step of melting the solder and fixing the components, the voids of the solder interposed between the components are suppressed, and the bridge or the like due to the scattering and flowing out of the solder to the outside of the fixed portion. A suitable solder fixing means for preventing soldering is provided, so that highly reliable solder fusion is enabled, and quality and yield are dramatically improved.

[Brief description of the drawings]

FIG. 1 is a simplified configuration diagram showing a first embodiment.

FIG. 2 is a sectional view (A1) and (B1) of FIG. 1 as viewed from above to explain a main part of FIG. 1, and FIG. 1 (A2) and FIG.
FIG. 2 is a front sectional view for explaining main parts of FIG.

FIG. 3A is a schematic diagram illustrating a state for explaining the first embodiment, and FIG. 3B is a diagram illustrating a solder melting temperature profile based on the schematic diagram (A).

FIG. 4A is a schematic diagram illustrating a state for explaining the second embodiment, and FIG. 4B is a diagram illustrating a solder melting temperature profile based on the schematic diagram (A).

FIG. 5 is a schematic diagram showing a conventional apparatus

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating part 2 Cold air ejection part 3 Automatic temperature setting control part 4 Elevating operation part 5 Base board 6 Solder 7 Components 8 Heating device 9 Temperature adjustment means 11 Heater 12 Opening / closing opening

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[Procedure amendment]

[Submission date] May 8, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 4

[Correction method] Change

[Correction contents]

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Minoru Tanaka, 1432-1 Fukae, Oji, Nijo-cho, Itoshima-gun, Fukuoka

Claims (4)

[Utility model registration claims] In a fusing apparatus for melting and fixing a component such as a semiconductor chip to a base substrate such as a metal for heat radiation, a melting start point of the component and a spreading direction of the molten surface which chain-links with the melting point for each component. And a fixing means for sequentially melting and cooling the solder with a predetermined time difference. 2. The solder fusion apparatus according to claim 1, further comprising a heating unit such as a hot plate that is divided and arranged in a lattice and that can individually adjust the temperature. 3. The apparatus according to claim 1, further comprising: a cooling air blow-out portion arranged in a lattice shape, each having an opening and closing opening and closing operation which can be independently opened and closed, and capable of adjusting a vertical movement and a cooling amount. Soldering equipment. 4. A means for setting a soldering temperature profile according to the type of a base substrate such as a heat-dissipating metal substrate or a component and the amount of solder at the joint, and in association therewith, the heating temperature of the heater and the cold air ejection. 4. An automatic temperature setting control unit provided with a means for generating a three-dimensional temperature gradient by interlockingly controlling the opening or closing operation of the unit opening / closing opening. Solder fusion equipment.