JP2015115606A - Down holder for pressing substrate position of substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a down holder with a simple structure and high reliability.SOLUTION: The down holder for pressing a position of a substrate includes a plate 1 including a center opening 2. The center opening becomes at least one substrate position that is accessible for fixing a die. The down holder further includes two other openings which are disposed while neighboring to any side of the center opening; a down holder plate 10 including an opening 11 and a down holder web 12; first and second air pressure drives; and a pressure line 9 for supplying a compression gas to pressure chambers of the two air pressure drives. Each air pressure drive includes cylinders 5 and 6 and a drive element. A pressure chamber is formed between the cylinder and the drive element. The cylinder 5 of the first drive is fixed to a first opening of the other openings, and the cylinder 6 of the second drive is fixed to a second opening of the other openings.

Description

  The present invention relates to a down holder for pressing a substrate position of a substrate.

  Such a down holder is used in an automatic mounter for mounting a component known as a “die” in the field, that is, a so-called die bonder, in order to push the substrate position of the substrate when it is mounted on a support base. Examples of dies include semiconductor chips, but also include capacitors, metal pieces, metal lids, and the like.

  When mounting a semiconductor chip, it is common sense to connect a semiconductor chip, mainly a power semiconductor, to a substrate by soldering in order to perform efficient heat dissipation of the semiconductor that occurs during operation by soldering connection. A suitable die bonder for this process is available from the applicant under the name DB2009 SSI. This die bonder includes a passing furnace having a down holder. The down holder is subjected to heat treatment from 300 ° C. to 450 ° C.

  The invention is based on the object of developing a downholder that can be used at working temperatures from 300 ° C. to 450 ° C. and has a simple structure and high reliability.

According to the present invention, the down holder for pressing the substrate position of the substrate is
A plate comprising a central opening and two separate openings arranged on both sides adjacent to the central opening;
A down holder plate comprising an opening and a down holder web disposed on the back side of the opening, the down holder plate being arranged on the back side of the plate so that the opening of the down holder plate is aligned with the central opening of the plate A down holder plate attached in a coupled manner;
First and second pneumatic drives, each of the first and second pneumatic drives includes a cylinder and a driving element, a pressure chamber is formed between the cylinder and the driving element, The driving cylinder is fixed to the first opening of another opening on the front side of the plate, and the second driving cylinder is fixed to the second opening of another opening on the front side of the plate. Pressure drive,
A first pressure line for providing compressed gas to two pneumatically driven pressure chambers.

  Preferably, the first pneumatic drive element comprises a spherical projection that engages a spherical recess in the downholder plate. The second pneumatically driven drive element comprises a spherical protrusion that engages an elongated recess in the downholder plate. The elongate recess of the down holder plate has a central portion with a circular cross section. The spherical protrusion of the first pneumatic drive element and the spherical recess of the down holder plate have the same radius, and the radius of the spherical protrusion of the second pneumatic drive element is the length of the elongated recess of the down holder plate. Equal to the radius of the cross section of the central part

  The pneumatically driven drive element can be, for example, a piston or a membrane.

  The downholder preferably further comprises a second pressure line for providing gas to the two pneumatically driven pressure chambers and a sensor for monitoring the pressure or gas flow in the second pressure line. Thereby, during operation, when the supply of the compressed gas is finished, it can be confirmed whether the piston or the membrane has returned to the retracted position.

  Supporting the downholder plate on the back side of the plate is advantageously done by screws. The screw is guided to the down holder plate by a telescopic spring arranged on the front side of the plate and a groove-free hole in the plate and tightened with a screw. The expansion spring is pre-tensioned so that the screw pulls the downholder plate to the back of the plate.

  The accompanying drawings are hereby incorporated by reference and constitute a part of this specification. The accompanying drawings illustrate one or more embodiments of the invention and, together with the detailed description, serve to explain the principles and practices of the invention. For clarity, the scale of the figure is not accurate.

1 shows a perspective view of a first embodiment of a down holder comprising a plate and a down holder plate according to the present invention. FIG. The down holder of 1st Embodiment seen from the bottom is shown. Fig. 3 shows a second embodiment of a down holder according to the invention as seen from below. Sectional drawing of the down holder in one operation state is shown. Sectional drawing of the down holder in one operation state is shown. FIG. 4 shows a cross-sectional view of a second embodiment of a downholder according to the invention.

  FIG. 1 shows in perspective view a first embodiment of a downholder according to the invention. The down holder comprises a plate 1, which comprises a central opening 2 and two separate openings 3 and 4 (FIGS. 4 and 5). The other openings 3 and 4 are arranged on either side adjacent to the central opening 2 and are preferably substantially circular, but may be of any other shape. The central opening 2 is elongated in this embodiment to allow access to the substrate location to which the substrate die is secured. The substrate positions are arranged in at least one row.

The downholder further comprises first and second pneumatic drives. Each of the two pneumatic drives contains cylinders 5 and 6 and a drive element, between which a pressure chamber is formed. The drive elements are, for example, movable pistons 7 and 8 (FIGS. 4 and 5) or elastically deformable and / or bendable membranes 18, 19 (FIG. 6). The first pneumatically driven cylinder 5 is fixed to the upper part of the opening 3 on the front side of the plate 1, and the second pneumatically driven cylinder 6 is arranged on the opening 4 on the front side of the plate 1. In embodiments with pistons 7 and 8, pistons 7 and 8 are movable perpendicular to the plane formed by plate 1, and in embodiments with membranes 18 and 19, membranes 18 and 19 are at least plate 1 Can be transformed into a plane formed by The first pressure line 9 is arranged on the front side of the plate 1 and provides compressed gas to two pneumatically driven pressure chambers. A protective gas is used as a compressed gas so that the substrate is not oxidized. A frequently used protective gas is nitrogen or a forming gas such as N ₂ H ₂ .

  The down holder further comprises a down holder plate 10 having an opening 11. FIG. 2 shows a partial view of the down holder of the first embodiment as viewed from below. In the present embodiment, the opening 11 is elongated, and therefore the down holder plate 10 has a cross shape. The down holder plate 10 includes a plurality of down holder webs 12 arranged in the opening 11 on the back side, that is, on the side opposite to the plate 1. The downholder web 12 is arranged along two elongated side edges of the opening 11 in this embodiment. The downholder web 12 may extend across the opening 11 if desired. The down holder plate 10 is disposed on the back side of the plate 1 and is mounted on the plate 1 so that the elongated opening 11 of the down holder plate 10 is aligned with the central opening 2 of the plate 1. The central opening of the plate 1 is also elongated in this embodiment. The down holder plate 10 is mounted on the plate 1 in a connected manner so that when the pneumatic drive is activated with compressed gas, the down holder plate 10 can be adjusted to the orientation of the substrate. The down holder plate 10 is fixed to the plate 1 with, for example, four screws 13. The screw 13 is guided to the down holder plate 10 by a telescopic spring 14 (FIG. 1) and a non-grooved hole in the plate 1 and fixed with a screw. The expansion spring 14 disposed between the screw thread of the screw 13 and the front side of the plate 1 is pre-tensioned. The expansion spring 14 therefore pushes the thread away from the plate 1, whereby the screw 13 pulls the down holder plate 10 toward the back side of the plate 1.

  The down holder plate 10 includes two recesses 15 and 16 on the front side. The recesses are arranged on both sides of the center of the opening 11, and the positions thereof are indicated by broken lines in FIG. In FIG. 2, the back side of the down holder plate 10 is shown. The recess 15 is spherical. Recess 16 is elongated and consists of a central portion with two generally hemispherical end regions and a circular cross section. In this embodiment, the longitudinal direction of the recess 16 extends at a right angle to the longitudinal direction of the elongated opening 11.

  FIG. 3 shows a cross-sectional view of a second embodiment of the down holder as seen from below. In this embodiment, the central opening 2 of the plate 1 and the opening 11 of the down holder plate 10 are also square or rectangular / rectangular, for example, so as to access the substrate position of a single substrate. Accordingly, each of the down holder plates 10 is wide and narrow or elongated. The longitudinal direction of the recess 16 of the down holder plate 10 extends in parallel with the longitudinal direction of the down holder plate 10 in the present embodiment.

  In both embodiments, the further openings 3 and 4 are preferably arranged symmetrically with respect to the central opening 2. Symmetry means that they are equidistant on both sides of the center of the opening 2.

  4 and 5 show, in cross-section, an embodiment downholder with pistons 7, 8 as drive elements. FIG. 4 shows a first operating state in which the two pneumatically driven pressure chambers are released. FIG. 5 shows the second operating state. In the second operating state, the two pneumatically driven pressure chambers are activated with compressed gas, and the pistons 7 and 8 push the down holder plate 10 against the substrate so as to leave the plate 1. Since the upper end portions of the pistons 7 and 8 have lower shoulder portions, the pistons 7 and 8 do not completely block the hole opening of the first pressure line 9.

  FIG. 6 shows a cross-sectional view of an embodiment downholder with membranes 18 and 19 as drive elements. A pressure chamber in which compressed gas may be provided is formed between the cylinders 5 and 6 and the membranes 18 and 19. The membranes 18 and 19 can be elastically deformed in a direction perpendicular to the plane formed by the plate 1. In this embodiment, the cylinders 5 and 6 may also be formed as indentations as an integral part of the plate 1. This indentation then forms a pressure chamber.

  The drive elements, ie the pneumatically driven pistons 7, 8 and the membranes 18, 19 are provided with spherical protrusions 17. Or a part with a spherical protrusion 17 is attached to the membranes 18 and 19. The first pneumatically driven piston 7 or the spherical protrusion 17 of the membrane 18 engages the spherical recess 15 of the down holder plate 10. The spherical protrusion 17 of the first pneumatically driven piston 7 or membrane 18 and the spherical recess 15 of the down holder plate have the same radius. As a result of this configuration, the down holder plate 10 may be tilted in any direction with respect to the plate 1 but cannot move. The spherical protrusion 17 of the second pneumatically driven piston 8 or membrane 19 engages the elongated recess 16 of the down holder plate 10. The radius of the spherical protrusion 17 of the second pneumatically driven piston 8 or membrane 19 is equal to the radius of the circular cross section of the central portion of the elongated recess 16 of the down holder plate 10. With this connected and supported configuration, the down holder plate 10 can be moved relative to the plate 1 and the down holder web 12 can be accurately aligned and adjusted relative to the substrate position of the substrate during the down holder setting. The down holder plate 10 can be tilted in any direction during the mounting operation, so that the down holder plate 10 can be adjusted relative to the substrate. The position of the spherical recess 15 of the down holder plate 10 with respect to the plate 1 is predetermined by the position of the first pneumatically driven piston 7 or the spherical protrusion 17 of the membrane 18. The spherical projection 17 of the second pneumatically driven piston 8 or membrane 19 is movable within the elongated recess 16 and can therefore compensate for the expansion of the plate 1 and the downholder plate 10 induced by heat. is there.

  The plate 1 and the two cylinders 5 and 6 may be integrated, or arranged such that the cylinders 5 and 6 are movably fixed to the plate 1. In the second case, the diameters of the openings 3 and 4 are such that the cylinders 5 and 6 can move within a certain range where the pistons 7 and 8 do not contact the openings 3 or 4. The cylinders 5 and 6 are fixed to the plate 1 by using, for example, two screws 20 (FIG. 1). The cylinders 5 and 6 are movable with respect to the screw 20. In this embodiment, it is advantageous that the position and alignment of the two pneumatic drives can be easily adjusted.

  In an embodiment with membranes 18, 19, when compressed gas is provided to the pneumatically driven pressure chamber, the membranes 18, 19 are elastically deformed and the protrusions 17 are therefore curved (downward). When the pressure chamber is ventilated, the down holder plate 10 that has been drawn to the back side of the plate 1 by the expansion spring 14 pushes the protrusion 17, whereby the membranes 18 and 19 are deformed in the opposite direction. The height of the cylinders 5, 6 is advantageously dimensioned so that in this case the membranes 18, 19 are present on the cylinder cover.

  The pistons 7 and 8 and the membranes 18 and 19 can take two positions. That is, the retracted position where the compressed gas is not supplied to the pressure chamber and the extended position where the compressed gas is provided to the pressure chamber.

  A second connected to two pneumatically driven pressure chambers and a sensor (not shown) to confirm whether the pistons 7, 8 or membranes 18, 19 have returned to the retracted position when the delivery of compressed gas is finished. Pressure lines 21 are provided. During operation, gas is provided to the second pressure line 21 at a permanently low pressure. Alternatively, when the compressed gas is supplied to the pressure chamber, the gas is supplied at a low pressure. When the piston 7, 8 or membrane 18, 19 returns to the retracted position, the piston 7, 8 or membrane 18, 19 closes the end of the associated second pressure line 21, so that the pressure in the pressure line 21 increases. Then the gas flow stops. If the pistons 7, 8 or the membranes 18, 19 have not returned to the retracted position, the gas provided from the pressure line 21 is the first pressure line 9 and / or the cylinder 5 or optionally associated with the pistons 7, 8 or It flows out of the gap between 6 and the pressure does not increase. The sensor is, for example, a pressure sensor that monitors the pressure of the pressure line 21. Alternatively, the sensor is a flow sensor that monitors the gas flow.

  While embodiments and applications of the present invention have been shown and described, it will be apparent to those skilled in the art that many more modifications than those described above can be made without departing from the inventive concepts described herein. The advantages of the present disclosure will be apparent. Accordingly, the invention is not limited except as by the appended claims and their equivalents.

Claims (6)

A down holder for pressing the substrate position of the substrate,
A plate (1) comprising a central opening (2) and two separate openings (3, 4) arranged adjacent to said central opening (2) on both sides thereof;
A down holder plate (10) comprising an opening (11) and a down holder web (12) disposed on the back side of the opening (11), wherein the down holder plate (10) A down holder plate (10) mounted on the back side so that the opening (11) of the down holder plate (10) is aligned with the central opening (2) of the plate (1); ,
First and second pneumatic drives, each of the first and second pneumatic drives comprises a cylinder (5, 6) and a drive element, the cylinder (5, 6) and the drive element And a cylinder (5) for the first drive is fixed to the first opening of the other opening (3) on the front side of the plate (1), The cylinder (6) of the second drive is fixed to a second opening of the other opening (4) on the front side of the plate (1);
A first pressure line (9) for providing compressed gas to the two pneumatically driven pressure chambers;
A down holder.   2. The down holder according to claim 1, wherein the drive element of the first pneumatic drive comprises a spherical protrusion (17) that engages a spherical recess (15) of the down holder plate (10). The drive element of the second pneumatic drive comprises a spherical protrusion (17) that engages an elongated recess (16) in the down holder plate (10), and an elongated recess ( 16) comprises a central part with a circular cross section, the spherical projection (17) of the drive element of the first pneumatic drive and the spherical recess (15) of the down holder plate (10) being identical. And the radius of the spherical protrusion (17) of the second pneumatically driven drive element is the radius of the cross section of the central portion of the elongated recess (16) of the downholder plate (10). Equal, downho Da.   The down holder according to claim 1 or 2, wherein the drive element of the pneumatic drive is a piston (7, 8).   The down holder according to claim 1 or 2, wherein the driving element of the pneumatic drive is a membrane (18, 19).   5. The down holder according to claim 3, wherein a second pressure line (21) for providing gas to the two pneumatically driven pressure chambers and the second pressure line (21). And a sensor for monitoring the pressure or gas flow in the piston (7, 8) or the membrane (18, 19) during operation when the supply of compressed gas is terminated. Down holders that can confirm whether each has returned to the retracted position.   The down holder according to any one of claims 1 to 5, wherein supporting the down holder plate (10) on the back side of the plate (1) is performed by a screw (13), The screw (13) is guided to the down holder plate (10) by the expansion spring (14) arranged on the front side of the plate (1) and the groove-free hole of the plate (1), and is fixed with screws. The extension holder (14) is pre-tensioned, whereby the screw (13) pulls the down holder plate (10) to the back side of the plate (1).

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