KR101344499B1 - Nozzle for injecting melted solder into cavities of template and apparatus having the same - Google Patents

Abstract

A nozzle and a device for injecting molten solder into cavities of a template, the solder injection nozzle comprising a cylindrical internal space for accommodating solder material and cavities formed in the surface portion of the template. A housing having a slot in communication with the internal space for injecting material, a heater connected to the housing to heat the housing to keep the solder material molten, and rotatably disposed in the internal space; A screw-shaped groove may include a piston formed on an outer circumferential surface thereof so that molten solder is injected into the cavities of the template through the slot.

Description

Nozzle for injecting melted solder into cavities of template and apparatus having the same

The present invention relates to a nozzle for injecting molten solder into cavities of a template and an apparatus comprising the same. More specifically, in microelectronic packaging technology, a nozzle and a solder including the same are used to inject molten solder into cavities formed in the surface portion of the template to form solder bumps. It relates to an injection device.

Recently, microelectronic packaging technology is changing from wire bonding to solder bump in the connection method. Techniques using solder bumps are widely known. For example, electroplating, solder paste printing, evaporation dehydration, direct attachment of solder balls, and the like are known.

Particularly, C4NP (controlled collapse chip connection new process) technology is attracting attention because it can realize fine pitch at a low cost and can improve the reliability of a semiconductor device. Examples of the C4NP technology are disclosed in U.S. Patent Nos. 5,607,099, 5,775,569, 6,025,258, and the like.

According to the C4NP technique, spherical solder bumps are formed in the cavities of the template and the solder bumps are thermocompressed onto the bump pads formed on the wafer. The bump pads are connected to metal wirings of a semiconductor chip formed on a wafer, and under bump metallurgy (UBM) pads may be provided on the bump pads. The UBM pads may be provided to improve the adhesion between the solder bumps and the bump pads.

The semiconductor chips of the wafer to which the solder bumps are transferred as described above can be individualized by the dicing process. The individualized semiconductor chip may be bonded onto a substrate through a thermal compression process and an underfill process, whereby a flip chip can be manufactured.

Molten solder may be injected into the cavities of the template to form the solder bumps. An example of a device for the injection of the molten solder is disclosed in U.S. Patent No. 6,231,333.

In the prior art, an injection head for injecting molten solder has a flat lower surface and performs sliding motion on a mold plate having a plurality of cells formed therein. An injection slot for injecting the molten solder, a vacuum slot for providing a vacuum pressure, and a recess connecting the injection slot and the vacuum slot are formed in a portion of the lower surface of the injection head. The molten solder is sequentially filled in the cells by the vacuum pressure during the sliding movement of the injection head.

According to the conventional technique, since the volume of the recess is small, it is difficult to adjust the inner pressure of the recess, and the molten solder may be sucked into the vacuum slot. In addition, since the structure of the injection head is complicated and the area of contact between the injection head and the mold plate is large, the molten solder may leak between the injection head and the mold plate.

It is a first object of the present invention to provide an improved nozzle for injecting molten solder into the cavities of a template.

It is a second object of the present invention to provide a solder injection apparatus comprising an improved nozzle for injecting molten solder into cavities of a template.

Solder injection nozzle according to an aspect of the present invention for achieving the first object is a cylindrical inner space for accommodating the solder material and the inner space for injecting the solder material in the cavities formed in the surface portion of the template A housing having a slot in communication with the housing, a heater connected to the housing to heat the housing to maintain the molten state of the solder material, and rotatably disposed in the internal space, wherein the molten solder is disposed through the slot. The screw-shaped groove may include a piston formed on the outer circumferential surface to be injected into the cavities of the template.

According to embodiments of the present invention, the slot may be formed on the lower surface of the housing, the lower surface of the housing is a flat rear end and the surface provided to be in surface contact with the surface portion of the template on both sides of the slot; It may include an inclined shear configured to be spaced apart from the surface portion of the template.

According to embodiments of the present invention, the front end portion of the lower surface may have a curved surface protruding downward.

According to embodiments of the present invention, a recess extending in parallel with the slot may be formed at the rear end of the lower surface. The recess while the nozzle scans the surface portion of the template to sequentially provide the molten solder to the cavities through the slot with the rear end of the bottom surface in contact with the surface portion of the template May be used to remove solder material remaining on the surface of the template.

Solder injection apparatus according to another aspect of the present invention for achieving the second object may include a solder injection nozzle and a pressure control unit for adjusting the pressure inside the solder injection nozzle. The solder injection nozzle is connected to the housing having a cylindrical internal space for accommodating solder material and a housing having a slot in communication with the internal space for injecting the solder material into cavities formed in the surface portion of the template. A heater for heating the housing to maintain the molten state of the solder material, and a screw-shaped groove disposed to be rotatable in the internal space and to inject the molten solder into the cavities of the template through the slot. It may include a piston formed on the outer peripheral surface. The pressure regulator may be connected to the inner space of the housing and supply purified air or inert gas to the inner space of the housing to maintain a constant pressure in the inner space of the housing.

According to the embodiments of the present invention as described above, the molten solder inside the solder injection nozzle is not injected into the cavities of the template due to the pressure difference between the inside and outside of the nozzle, but the screw disposed inside the solder injection nozzle It can be injected by a piston in the form. Therefore, it is not necessary to control the pressure difference and precisely control the discharge amount of the molten solder.

In addition, since the contact area between the nozzle and the template is relatively small compared to the conventional injection head, leakage of molten solder between the nozzle and the template can be reduced.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments, but may be implemented in other forms. The embodiments introduced herein are provided to make the disclosure more complete and to fully convey the spirit and features of the invention to those skilled in the art. In the drawings, the thickness of each device or component and regions are exaggerated for clarity of the present invention, and each device may additionally include various additional components not described herein, Is referred to as being located on another component or device, it may be directly disposed on or interposed between the other component or device.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic diagram for explaining an apparatus for injecting molten solder according to an embodiment of the present invention; FIG.

Referring to FIG. 1, the injection device 100 of molten solder may include a process chamber 102 in which an injection process of molten solder 10 is performed. The process chamber 102 provides an enclosed space, and within the process chamber 102 a chuck 104 supporting a template 20 having a plurality of cavities 22 (see FIG. 2) formed at a surface portion thereof. This can be arranged.

In addition, a nozzle 110 (see FIG. 2) for providing molten solder 10 may be disposed in the process chamber 102. However, the nozzle 110 may extend upward through the top panel of the process chamber 102.

The nozzle 110 may include a housing 112, a piston 114, and a first heater 116. The housing 112 may have a cylindrical inner space for accommodating the solder material. The housing 112 may be connected to the first heater 116, and the first heater 116 melts the solder material and maintains the solder material in a molten state at or above the melting point of the solder material. The housing 112 may be heated to a temperature. For example, an electric resistance heating wire that may be embedded in the housing 112 may be used as the first heater 116. In addition, a slot 112a (see FIG. 2) communicating with the inner space is formed at a lower portion of the housing 112 to discharge the molten solder 10 to the outside.

The piston 114 may be disposed to be rotatable inside the housing 112. In particular, a screw-shaped groove may be formed on the outer circumferential surface of the piston 114. As a result, the molten solder 10 may be discharged to the outside of the housing 112 by the rotation of the piston (114).

Meanwhile, the molten solder 10 may include tin (Sn), silver (Ag), copper (Cu), bismuth (Bi), indium (In), and the like, which may be used alone or in combination. Can be.

The injection device 100 of the molten solder 10 includes a first drive unit 118 and a first drive unit 118 for generating a relative sliding motion between the nozzle 110 and the template 20 supported by the chuck 104. 2 may include a driving unit 120. As shown, the first driving unit 118 may move the nozzle 110 in the vertical direction such that the lower end portion of the nozzle 110 contacts the surface portion of the template 20, and the second The driving unit 120 is disposed between the nozzle 110 and the template 20 so that the molten solder 10 is sequentially injected into the cavities 22 from the nozzle 110 in contact with the template 20. Relative motion can occur at For example, the second driver 120 may move the chuck 104 in the horizontal direction.

For example, each of the first drive unit 118 and the second drive unit 120 may include a hydraulic or pneumatic cylinder. Alternatively, each of the first driver 118 and the second driver 120 may include a single axis driver including a motor and a linear motion guide. However, the configuration of the first and second drivers 118 and 120 may be changed in various ways, and the scope of the present invention is limited by the configurations of the respective first and second drivers 118 and 120. It won't be.

In addition, the configuration of the driving units for generating a relative sliding motion between the nozzle 110 and the chuck 104 may be variously changed. For example, the solder injection apparatus 100 may include one driving unit for moving the nozzle 110 or the chuck 104 in the horizontal and vertical directions. In addition, it may include a first drive for moving the chuck 104 in the vertical direction and a second drive for moving the nozzle 110 in the horizontal direction.

In addition, the solder injection apparatus 110 may further include a third driver 122 for rotating the piston 114 inside the housing 112. The third driving unit 122 may include a motor and a speed reducer for adjusting the rotation speed.

The genital chuck 104 may be connected to the second heater 124, and the second heater 124 may be provided to adjust the temperature of the template 20. In particular, the second heater 124 may be embedded in the chuck 104 and may include an electric resistance heating wire. For example, the second heater 124 may adjust the temperature of the template 20 to a temperature lower than the melting point of the solder. In particular, the second heater 124 may adjust the temperature of the template 20 by about 3 ° C. to about 10 ° C. below the temperature of the nozzle 110. When the temperature of the template 20 is excessively low, the temperature of the nozzle 110 in contact with the template 20 may be lowered, so that the solder inside the nozzle 110 may solidify. In addition, when the temperature of the template 20 is higher than the melting point of the solder, the molten solder 10 injected into the cavities 22 may not solidify.

2 and 3 are enlarged cross-sectional views illustrating the nozzle illustrated in FIG. 1, and FIG. 4 is a plan view illustrating the relative motion between the nozzle and the template illustrated in FIG. 1.

2 and 3, the housing 112 may have a cylinder shape in which upper and lower portions are closed, and the slot 112a may be formed through a closed lower surface portion of the housing 112.

For example, the slot 112a may extend in a direction perpendicular to the relative direction of movement between the nozzle 110 and the template 20 at the central portion of the lower surface of the housing 112. In particular, the lower surface of the housing 112 is configured to be spaced apart from the flat rear end portion provided to be in surface contact with the surface portion of the template 20 to both sides of the slot (112a) and the surface portion of the template 20. It may comprise a photographic front end.

The front end portion of the lower surface may be provided to prevent the movement interference between the housing 112 and the template 20 by the relative movement. Therefore, it is possible to prevent the surface portion of the template 20 from being damaged by the movement interference. In particular, as shown, the front end portion of the lower surface may have a curved surface protruding downward to facilitate the relative sliding movement.

Meanwhile, in the process of injecting the molten solder 10 into the cavities 22 by the relative movement between the nozzle 110 and the template 20 and the rotation of the piston 114, the nozzle ( Leakage may occur between 110 and template 20. That is, solder residue may be formed on the surface portion of the template 20. In order to solve the above problems, a recess 112b extending in parallel with the slot 112a may be formed at the rear end of the lower surface. The recess 112b may be provided to remove the solder residue from the surface portion of the template 20.

Referring to FIG. 4, the template 20 may have a flat upper surface, and the cavities 22 may be formed in the upper surface portion. The template 20 may have a mold region 20a having a shape similar to that of a semiconductor wafer and a peripheral region 20b surrounding the mold region 20a, (20a).

On the other hand, the diameter of the nozzle 110 may be larger than the diameter of the mold region 20a. In this case, the nozzle 110 may inject molten solder into the cavities 22 of the mold region 20a in one scan operation. However, the diameter of the nozzle 110 may be smaller than the mold region 20a, in which case the nozzle 110 may undergo cavities 22 of the mold region 20a through a number of repetitive scan operations. ) Can be injected into the molten solder.

Referring back to FIG. 1, the molten solder injection apparatus 100 may include a process controller 130 for controlling a solder injection process.

FIG. 5 is a schematic diagram illustrating the process control unit illustrated in FIG. 1.

Referring to FIG. 5, the process controller 130 may include a temperature controller 140 and a pressure controller 150.

The temperature controller 140 includes a first temperature sensor 142 connected to the nozzle 110, a second temperature sensor 144 connected to the chuck 104, and a temperature sensor 140 connected to the first and second temperature sensors A control unit 146, and the like. The temperature control unit 146 is connected to the first and second temperature sensors 142 and 144 and detects the temperature of the nozzle 142 based on the temperature signals provided from the first and second temperature sensors 142 and 144. [ 110 and control signals for controlling the temperature of the chuck 104 may be generated. That is, the first heater 112 and the second heater 114 may be controlled by the control signals of the temperature controller 146.

The pressure regulator 150 may include a first pressure sensor 152 for measuring the pressure in the process chamber 102, a second pressure sensor 154 for measuring the pressure in the nozzle 110, and A pressure control unit 156 for generating control signals for adjusting an internal pressure of the process chamber 102 and an internal pressure of the nozzle 110, and connected to the pressure control unit 156 to the process chamber 102. It may include a gas providing unit 160 for providing purified air or inert gas into the nozzle 110 and a vacuum providing unit 170 for evacuating the process chamber 102 and the inside of the nozzle 110. have.

The gas supply 160 may include a gas storage vessel 162 for storing an inert gas and the gas storage vessel 162 is connected to the nozzle 110 and the process chamber 102 ). Off valves 164 and a mass flow controller 166 may be provided on each of the gas supply lines and may be provided to the process chamber (not shown) by the on / off valves 164 and mass flow controllers 166. [ 102 and the nozzle 110 can be controlled. As the inert gas, nitrogen (N ₂ ), argon (Ar), helium (He), or the like may be used. Thus, the molten solder 10 in the nozzle 110 and the molten solder or solidified solder injected into the cavities 22 can be prevented from being contaminated.

The vacuum supply unit 170 may include a vacuum pump 172 and a buffer tank 174 and the vacuum pump 172 may be connected to the buffer tank 174 by a first vacuum line, The buffer tank 174 may be connected to the nozzle 110 and the process chamber 102 by second vacuum lines. On each of the second vacuum lines, an on / off valve 176 and a mass flow controller 178 may be provided.

The on / off valves 164 and 176 and the mass flow controllers 166 and 178 of the gas supplier 160 and the vacuum supplier 170 are connected to the pressure controller 156, 156, respectively.

The pressure inside the process chamber 102 can be kept lower than atmospheric pressure or atmospheric pressure. For example, the pressure inside the process chamber 102 can be regulated at about 760 Torr to about 50 mTorr. The pressure inside the nozzle 110 may be lowered by the injection of the molten solder 10, and the pressure adjusting unit 150 may use an inert gas to maintain a constant pressure inside the nozzle 110. Can supply In particular, the pressure inside the process chamber 102 and the pressure inside the nozzle 110 may be maintained to be substantially the same while the injection process of the molten solder 10 is performed. In addition, before and after the solder injection process, the pressure inside the nozzle 110 may be adjusted to be equal to or lower than the internal pressure of the process chamber 102. This is to prevent the molten solder 10 inside the nozzle 110 from leaking through the slot 112a.

On the other hand, according to another embodiment of the present invention, the pressure regulator 150 may supply purified air instead of inert gas. In this case, the pressure regulator 150 may include a filter unit for removing chemical contaminants and particles contained in the air.

Referring back to FIG. 1, the process chamber 102 may have a gate door 106 for loading and unloading the template 20. The template 20 carried into the process chamber 102 through the gate door 106 may be supported by the chuck 104. Here, although not shown, the molten solder injection apparatus 100 may further include a lifting unit for loading and unloading the template 20. For example, the lifting unit may include a plurality of lift pins arranged to be vertically movable through the chuck 104, and a driving unit for providing a driving force to the lift pins. However, the configuration of the lifting unit may be variously changed, and the scope of the present invention is not limited by the configuration of the lifting unit.

Next, a method of injecting the molten solder 10 into the cavities 22 of the template 20 using the molten solder injecting apparatus 100 will be described in detail with reference to the accompanying drawings.

A template 20 having a surface portion where a plurality of cavities 22 is formed is introduced into the process chamber 102 through the gate door 106 of the process chamber 102. The template 20 is loaded onto the chuck 104 inside the process chamber 102 by a lifting unit. Here, the template 20 may be transferred into the process chamber 102 by an external transfer module (not shown).

After the template 20 is loaded, the inside of the process chamber 102 is adjusted to a pressure below atmospheric pressure. At this time, the gas supplier 160 supplies an inert gas into the process chamber 102, and the vacuum supplier 170 evacuates the gas inside the process chamber 102. This is to remove contaminants inside the process chamber 102. Meanwhile, the housing 112 is heated to a temperature equal to or higher than the melting point of the solder by the first heater 116, thereby maintaining the solder in the molten state inside the housing 112. In addition, the internal pressure of the nozzle 110 is maintained lower than the internal pressure of the process chamber 102 so that the molten solder 10 does not leak through the slot 112a of the nozzle 110. That is, the pressure difference between the process chamber 102 and the nozzle 110 is kept constant while adjusting the pressure inside the process chamber 102.

Meanwhile, the template 20 is heated to a temperature lower than the melting point of the solder by the second heater 124. At this time, the temperature difference between the nozzle 110 and the template 20 may be maintained at about 3 캜 to about 10 캜, for example, about 5 캜.

After the internal pressure regulation of the process chamber 102 is completed, the second drive unit 120 is under the nozzle 110 to provide the molten solder 10 to the template 20 supported by the chuck 104. Next, the first drive unit 118 moves the nozzle 110 downward so that the nozzle 110 contacts the surface portion of the peripheral area 20b of the template 20. Here, since the contact area between the nozzle 110 and the template 20 is smaller than that of the conventional injection head, the leakage of the molten solder 10 between the nozzle 110 and the template 20 is reduced. Can be reduced or avoided.

After contacting the nozzle 110 with the template 20, the pressure inside the nozzle 110 is adjusted to be substantially equal to the pressure inside the process chamber 102. The pressure inside the nozzle 110 may be adjusted by supplying an inert gas into the nozzle 110.

Subsequently, the second driver 120 moves the chuck 104 in a horizontal direction to generate a relative sliding motion between the nozzle 110 and the template 20. In addition, the third driver 122 rotates the piston 114 to discharge the molten solder 10 inside the housing 112. As a result, the molten solder 10 is sequentially injected into the cavities 22 of the template 20 by the relative sliding motion and rotation of the piston 114 as shown in FIGS. 2 and 3. Can be. In particular, since the lower surface of the housing 112 has an inclined front end portion during the sliding movement, the damage of the template 20 can be prevented, and the recess 112b of the rear end of the lower surface of the housing 112 can be prevented. This allows the solder residue on the template 20 to be sufficiently removed.

The solder 10a injected into the cavities 22 may be solidified due to the temperature difference between the nozzle 110 and the template 20.

After the injection of the molten solder 10 is completed, the pressure inside the nozzle 110 is lower than the pressure inside the process chamber 102 so that the molten solder 10 does not leak through the slit of the nozzle 110. Pressure.

After adjusting the pressure inside the nozzle 110, the first driving unit 118 moves the nozzle 110 upwards, and then the second driving unit 120 moves the chuck 104 to the upper surface of the nozzle 110. Move to a point adjacent to the gate door 106.

Subsequently, the template 20 is unloaded from the chuck 104 by the lifting unit, and is taken out of the process chamber 102 by the transfer module.

6 is a schematic cross-sectional view for describing a solder injection nozzle according to another embodiment of the present invention.

Referring to FIG. 6, the solder injection nozzle 210 for injecting the molten solder 10 into the cavities of the template includes a main body 212 having a cylindrical inner space and a closed upper cylinder, and the inner portion of the template. A piston 214 disposed to be rotatable in the space, a heater 216 connected to the main body 212 and heating the main body 212, and a lower part connected to the lower part of the main body 212 and extending in one direction The structure 218 can be included.

The lower structure 218 may extend in a direction perpendicular to the relative sliding movement direction between the template and the nozzle 210, and may be formed inside the body 212 to discharge the molten solder 10. It may have a slot 218a in communication with the space. In addition, although not shown in detail, the lower surface of the lower structure 218 may have an inclined front end and a flat rear end with respect to the slot 218a, and the flat rear end may be parallel to the slot 218a. Recesses may be formed that extend.

Further detailed description of the components of the nozzle 210 as described above is similar to the description of the nozzle 110 described above with reference to FIGS. 2 to 3 and will be omitted.

According to the embodiments of the present invention as described above, since the structure of the nozzle for injecting molten solder is simpler than the conventional injection head, the manufacturing cost of the nozzle can be reduced. Also, since the contact area between the nozzle and the template is relatively small, leakage of the molten solder between the nozzle and the template can be reduced or prevented.

The molten solder inside the solder injection nozzle may be injected by a screw shaped piston disposed inside the solder injection nozzle, rather than injected into the cavities of the template due to the pressure difference between the inside and the outside of the nozzle. Therefore, it is not necessary to control the pressure difference and precisely control the discharge amount of the molten solder.

In addition, damage to the template may be prevented by recesses of the inclined front and rear ends of the nozzle lower surface, and the solder residue on the template may be sufficiently removed.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims It can be understood that

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic diagram for explaining an apparatus for injecting molten solder according to an embodiment of the present invention; FIG.

2 and 3 are enlarged cross-sectional views for describing the nozzle shown in FIG. 1.

4 is a plan view for explaining a relative motion between the nozzle and the template shown in FIG.

FIG. 5 is a schematic diagram illustrating the process control unit illustrated in FIG. 1.

6 is a schematic cross-sectional view for describing a solder injection nozzle according to another embodiment of the present invention.

Description of the Related Art [0002]

10: melted solder 20: template

20a: mold area 20b: peripheral area

22: Cavity 100: Solder injection device

102 chamber 104 chuck

106: gate door 110: nozzle

112: housing 112a: slot

112b: recess 114: piston

116: first heater 118: first drive unit

120: second driver 122: third driver

124: second heater 130: process control

140: temperature control unit 146: temperature control unit

150: pressure adjusting unit 160: gas providing unit

170: vacuum providing unit

Claims (5)

A housing having a cylindrical interior space for receiving solder material and a slot in communication with the interior space for injecting the solder material into cavities formed in the surface portion of the template; A heater connected to the housing and heating the housing to maintain the molten state of the solder material; And And a piston disposed rotatably in the inner space and having a groove formed on an outer circumferential surface of a screw-shaped groove so that the molten solder is injected into the cavities of the template through the slot. According to claim 1, wherein the slot is formed in the lower surface of the housing, the lower surface of the housing is a flat rear end and the surface portion of the template provided to be in surface contact with the surface portion of the template on both sides of the slot. And a slanted shear configured to be spaced apart from the solder injection nozzle. The solder injection nozzle of claim 2, wherein the front end portion of the lower surface has a curved shape protruding downward. The solder injection nozzle of claim 2, wherein a recess extending in parallel to the slot is formed at a rear end of the lower surface. A housing having a slot in communication with the inner space for injecting the solder material into the cylindrical inner space for accommodating the solder material and the cavities formed in the surface portion of the template, and connected to the housing to melt the solder material A heater for heating the housing to maintain a closed state, and a piston disposed rotatably in the inner space and having a screw groove formed on an outer circumferential surface thereof so that the molten solder is injected into the cavities of the template through the slot. A solder injection nozzle comprising; And And a pressure regulator connected to an inner space of the housing and supplying purified air or an inert gas to the inner space of the housing to maintain a constant pressure in the inner space of the housing.

Images