JP2013191781A - Semiconductor manufacturing apparatus and control method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor manufacturing apparatus which peels and takes up a semiconductor chip from an adhesive sheet in a high quality state, and to provide a control method of the semiconductor manufacturing apparatus.SOLUTION: A holding stage 10 of a pick up device includes: a first stage 11 where semiconductor chips 1a are placed through an adhesive sheet 2; and a contact prevention plate 31 preventing the semiconductor chips 1a placed on the first stage 11 from contacting with each other. In the pick up device, the semiconductor chips 1a are placed on a surface of the first stage 11 where grooves 21 are provided. The contact prevention plate 31 is disposed at a predetermined position above the first stage 11 so as to be spaced a predetermined distance away from the first stage 11. A closed space 23 enclosed by the grooves 21 and the adhesive sheet 2 is decompressed by decompression means. Each semiconductor chip 1a is held by protruding parts 22, each of which is formed by side walls of the adjacent grooves 21, and then the contact prevention plate 31 is moved to a position away from the first stage 11. The semiconductor chip 1a is picked up by a collet.

Description

  The present invention relates to a semiconductor manufacturing apparatus and a semiconductor manufacturing apparatus control method.

  In recent years, IGBTs (Insulated Gate Bipolar Transistors) have been made thinner in order to achieve higher performance and lower costs. For example, in order to increase the performance and cost of the IGBT, it is necessary to reduce the thickness of the semiconductor wafer to a thickness of about 50 μm to 100 μm or less.

  The following method has been proposed as a method for manufacturing a semiconductor device having a thin device thickness. After the device structure is formed on the front surface of the semiconductor wafer, back grinding or silicon etching is performed on the back surface of the semiconductor wafer until a predetermined thickness is reached. Then, dicing is performed for each device structure formed on the front surface of the semiconductor wafer, and the semiconductor wafer is cut into individual semiconductor chips.

  Further, the following method has been proposed as another method for manufacturing a semiconductor device having a thin device thickness. After the device structure is formed on the front surface of the semiconductor wafer, a groove deeper than a predetermined thickness after completion of the semiconductor device, for example, is formed on the front surface of the semiconductor wafer along the dicing line. Then, the semiconductor wafer is cut into individual semiconductor chips by grooves formed on the front surface by performing back grinding or silicon etching on the back surface of the semiconductor wafer and thinning the semiconductor wafer to a predetermined thickness. .

  As another method for manufacturing a semiconductor device having a thin device thickness, the following method has been proposed. After the device structure is formed on the front surface of the semiconductor wafer, back grinding and silicon etching are performed on the back surface of the semiconductor wafer, and only the central portion of the semiconductor wafer is thinned within a range narrower than the diameter of the semiconductor wafer. The outer peripheral part (hereinafter referred to as a rib part) is left. Then, dicing is performed while leaving the rib portion of the semiconductor wafer or after removing the rib portion, and the semiconductor wafer is cut into individual semiconductor chips.

  In order to avoid problems such as scattering of semiconductor chips separated by dicing when dicing the semiconductor wafer in this way, for example, a method of dicing by attaching an adhesive sheet such as a dicing sheet to the back surface of the semiconductor wafer Is known. After sticking the adhesive sheet on the back side of the semiconductor wafer and dicing, put the semiconductor chip attached and fixed to the adhesive sheet into the pickup device for picking up the semiconductor chip, and pick up from the adhesive sheet To separate individual semiconductor chips.

  The following method has been proposed as a method for picking up a semiconductor chip from an adhesive sheet. The contact area between the semiconductor chip and the pressure-sensitive adhesive sheet is reduced by pushing the semiconductor chip upward from, for example, a needle from the back side where the pressure-sensitive adhesive sheet is attached. The semiconductor chip pushed upward by the needle is picked up from the adhesive sheet by sucking the upper surface of the semiconductor chip with a collet or the like, and is conveyed to a die pad or the like on which the semiconductor chip is mounted. However, when the semiconductor chip is thinned, there is a possibility that the back surface of the semiconductor chip may be damaged or the semiconductor chip may be damaged by the pushing-up by the needle.

  In order to solve such a problem, the following method has been proposed as a method in which the needle is not pushed up. The fixed jig includes a jig base having a plurality of protrusions and side walls on one surface, and an adhesion layer laminated on the surface having the protrusions of the jig base and bonded to the upper surface of the side walls. A partition space is formed on the surface of the jig base having the protrusions by the adhesion layer, the protrusions, and the side walls, and is connected to a vacuum source by a through hole. Air in the partition space is sucked through the through hole to deform the adhesion layer, and the suction collet sucks the chip from the upper surface side of the chip and picks up the chip from the adhesion layer (for example, refer to Patent Document 1 below). .

  As another method, a plurality of suction grooves distributed so as to cover a region facing the chip-shaped component, and at least two locations between these suction grooves and partially facing each chip-shaped component. The holding sheet is placed on a mounting table having a protrusion positioned as described above, and a negative pressure is applied to the suction groove, thereby deforming the holding sheet along the protrusion and trying to peel it off from the chip-like component. First, a method has been proposed in which the negative pressure applied to the suction groove facing the peripheral edge of the chip-shaped component is further increased so that the holding sheet is peeled off from the peripheral edge of the chip-shaped component (for example, the following) (See Patent Document 2).

  As another method, the following method has been proposed. On the surface on which the back side of the semiconductor chip is placed via the dicing tape of the suction piece, a suction surface that is concave and substantially hemispherical and has a plurality of protrusions of the same height rising vertically. And a side wall having a width of 0.4 mm or less and a height equal to the height of the protrusion or a difference between the height of the protrusions of less than 1 mm. Then, the dicing tape is sucked from the suction holes provided in at least one of the valleys between the protrusions and / or the side surfaces of the protrusions, and sucked into the protrusions, and colleted from the front surface side of the semiconductor chip. Pick up the semiconductor chip. When adsorbing the dicing tape from the adsorbing hole, the dicing tape is slightly submerged between the adsorbing side wall and the adsorbing surface within the range of elasticity of the dicing tape (for example, the following patent document) 3).

  In addition, the following apparatus has been proposed as a pickup apparatus that avoids damage to the semiconductor chip. The wafer mounting table is connected to the plurality of protrusions that hold the lower surface of the IC chip through the adhesive sheet at the top, the suction grooves formed in the valleys of the plurality of protrusions, and the suction grooves via a connection tube. A vacuum device that peels the adhesive sheet from the IC chip and attracts it to the valleys of the protrusions by generating a suction force in the suction groove (see, for example, Patent Document 4 below).

JP 2008-103493 A JP 11-54594 A JP 2010-123750 A JP-A-5-335405

However, the techniques shown in the above-described patent documents have the following problems. FIG.
These are sectional drawings which show the semiconductor chip of the state hold | maintained at the holding stage of the conventional semiconductor manufacturing apparatus. FIG. 13 shows a state in which the adhesive sheet 102 that fixes the plurality of semiconductor chips 101a is deformed along the protrusions 111a of the holding stage 111, and the adhesive sheet 102 is intermittently peeled from the semiconductor chip 101a. As shown in FIG. 13, when the adhesive sheet 102 is deformed, if the timing at which the adhesive sheet 102 is peeled from the semiconductor chip 101a is different within the surface of one semiconductor chip 101a-1, the adhesive sheet 102 is peeled off quickly. The part will float. That is, the semiconductor chip 101a-1 is inclined with respect to the holding stage 111 before the semiconductor chip 101a-1 is sucked by the collet.

  When the semiconductor chip 101a-1 is inclined with respect to the holding stage 111, the end of the semiconductor chip 101a-1 comes into contact with the adjacent semiconductor chip 101a-2, and the semiconductor chips 101a-1 and 101a-2 come into contact with each other. There is a risk of chipping. Further, when the semiconductor chip 101a-1 is inclined with respect to the holding stage 111, the end of the semiconductor chip 101a-1 on the raised side collides with a collet (not shown), and the semiconductor chip 101a-1 There is a risk of scratching.

  In addition, the adhesive strength between the semiconductor chip 101a and the adhesive sheet 102 varies depending on the surface roughness of the back surface of the semiconductor chip 101a and the presence or absence of a metal film, and the adhesive strength and rigidity vary depending on the material of the base material and adhesive layer constituting the adhesive sheet 102. The ease with which the pressure-sensitive adhesive sheet 102 is deformed into the protrusion 111a varies depending on factors such as change. For this reason, it is difficult to control the deformation of the pressure-sensitive adhesive sheet 102 to the protrusion 111a. Therefore, the techniques shown in the above-mentioned patent documents cannot prevent the semiconductor chip 101a-1 from being inclined with respect to the holding stage 111 as described above.

  An object of the present invention is to provide a semiconductor manufacturing apparatus and a semiconductor manufacturing apparatus control method capable of peeling and picking up a semiconductor chip from a pressure-sensitive adhesive sheet in a high-quality state in order to eliminate the above-described problems caused by the prior art. To do.

  In order to solve the above-described problems and achieve the object of the present invention, a semiconductor manufacturing apparatus according to the present invention is a semiconductor manufacturing apparatus that picks up a semiconductor chip cut by dicing from an adhesive sheet, and has the following characteristics. A stage on which the semiconductor chip is placed is provided. A groove is provided on the surface of the stage on which the semiconductor chip is placed. The surface of the stage on which the semiconductor chip is placed is provided with an apex portion that is formed by an end portion on the opening side of the groove and holds the semiconductor chip via the adhesive sheet. The stage is provided with at least one vent hole connected to the groove. Depressurization that decompresses the pressure-sensitive adhesive sheet attached to the stage-side surface of the semiconductor chip placed on the stage and the space surrounded by the groove provided in the stage through the vent hole Means. A suction means for sucking and picking up the semiconductor chip held at the apex portion when the space is decompressed by the decompression means. A contact prevention plate is disposed above the stage at a predetermined interval and prevents the semiconductor chips from contacting each other when the space is decompressed by the decompression means.

  In the semiconductor manufacturing apparatus according to the present invention, in the above-described invention, before the space is decompressed by the decompression unit, the contact prevention plate is moved above the stage, and the semiconductor chip is fabricated by the suction unit. It further includes moving means for moving the contact prevention plate to a position that does not hinder the operation of the suction means before picking up is started.

  In the semiconductor manufacturing apparatus according to the present invention, in the above-described invention, the length a of one side of the semiconductor chip, the thickness b of the semiconductor chip, and the interval c between the adjacent semiconductor chips are obtained by dicing. The contact prevention plate is disposed above the stage on which the cut rectangular semiconductor chip is placed, with a predetermined interval x satisfying the following expression (1).

  In the semiconductor manufacturing apparatus according to the present invention as set forth in the invention described above, the contact prevention plate faces the main surfaces of all the semiconductor chips placed on the stage.

  Further, in order to solve the above-described problems and achieve the object of the present invention, a method for controlling a semiconductor manufacturing apparatus that picks up a semiconductor chip cut by dicing from an adhesive sheet has the following characteristics. A mounting step of mounting the semiconductor chip on the surface provided with the groove of the stage is performed with the surface on the side where the adhesive sheet is affixed as the stage side. Next, the space surrounded by the groove and the adhesive sheet is depressurized, and a depressurizing step is performed in which the semiconductor chip is held at the apex formed by the end portion on the opening side of the groove. In the depressurization step, the semiconductor chips are prevented from contacting each other by a contact prevention plate disposed above the stage at a predetermined interval. Next, a suction step of sucking and picking up the semiconductor chip held at the apex portion by a suction means is performed.

  The semiconductor manufacturing apparatus control method according to the present invention further has the following characteristics in the above-described invention. Before the decompression step, a first movement step of moving the contact prevention plate above the stage is performed. After the placing step, a second moving step of moving the contact prevention plate to a position that does not hinder the operation of the suction means is performed before the suction step.

  The method for controlling a semiconductor manufacturing apparatus according to the present invention further has the following characteristics in the above-described invention. In the placing step, the rectangular semiconductor chip cut by dicing so as to have a length a of one side of the semiconductor chip, a thickness b of the semiconductor chip, and an interval c between the adjacent semiconductor chips is obtained. Place on the stage. In the first moving step, the contact prevention plate is disposed above the stage with a predetermined interval x satisfying the following expression (2).

  Moreover, the control method of the semiconductor manufacturing apparatus according to the present invention is characterized in that, in the above-described invention, the contact prevention plate is opposed to the main surface of all the semiconductor chips placed on the stage.

  According to the above-described invention, the contact prevention plate is disposed at a predetermined position above the stage at a predetermined interval while the closed space surrounded by the adhesive sheet and the groove of the stage is depressurized by the decompression unit. Even if the semiconductor chip is inclined with respect to the stage, the inclination angle of the semiconductor chip can be suppressed to such an extent that it does not come into contact with other adjacent semiconductor chips. Thereby, chipping and scratching of the semiconductor chips caused by the contact between adjacent semiconductor chips can be prevented.

  Further, according to the embodiment, the contact prevention plate faces the main surface of all the semiconductor chips placed on the stage, so that chipping or scratching of all the semiconductor chips placed on the stage can be prevented. it can. In addition, according to the embodiment, when picking up the semiconductor chip by the suction means, the contact prevention plate is moved to a position that does not interfere with the operation of the collet, and therefore the suction means that performs the same operation as the conventional pickup device is used. be able to.

  According to the semiconductor manufacturing apparatus and the method for controlling the semiconductor manufacturing apparatus according to the present invention, there is an effect that the semiconductor chip can be peeled off and taken up from the adhesive sheet in a high quality state.

It is a top view which shows the semiconductor wafer processed with the semiconductor manufacturing apparatus concerning embodiment. FIG. 2 is a plan view showing a state after dicing of the semiconductor wafer shown in FIG. 1. It is a perspective view which shows typically the principal part of the semiconductor manufacturing apparatus concerning Embodiment. It is sectional drawing which shows typically the principal part of the semiconductor manufacturing apparatus concerning Embodiment. It is sectional drawing which shows the state after mounting the semiconductor chip in the semiconductor manufacturing apparatus concerning embodiment. It is a bird's-eye view which shows typically the principal part of the semiconductor manufacturing apparatus concerning an embodiment. It is sectional drawing which shows the semiconductor chip of the state mounted in the holding | maintenance stage of the semiconductor manufacturing apparatus concerning embodiment. FIG. 8 is a cross-sectional view showing a state where adjacent semiconductor chips shown in FIG. 7 are in contact with each other. It is sectional drawing shown in order about operation | movement of the semiconductor manufacturing apparatus concerning Embodiment. It is sectional drawing shown in order about operation | movement of the semiconductor manufacturing apparatus concerning Embodiment. It is sectional drawing shown in order about operation | movement of the semiconductor manufacturing apparatus concerning Embodiment. It is sectional drawing shown in order about operation | movement of the semiconductor manufacturing apparatus concerning Embodiment. It is sectional drawing which shows the semiconductor chip of the state hold | maintained at the holding stage of the conventional semiconductor manufacturing apparatus.

  Exemplary embodiments of a semiconductor manufacturing apparatus and a method for controlling the semiconductor manufacturing apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings. Note that, in the following description of the embodiments and the accompanying drawings, the same reference numerals are given to the same components, and duplicate descriptions are omitted.

(Embodiment)
FIG. 1 is a plan view showing a semiconductor wafer processed by the semiconductor manufacturing apparatus according to the embodiment. FIG. 2 is a plan view showing a state after dicing of the semiconductor wafer shown in FIG. The semiconductor wafer 1 before being processed by the semiconductor manufacturing apparatus according to the embodiment will be described. As shown in FIGS. 1 and 2, the semiconductor wafer 1 is diced with the adhesive sheet 2 attached thereto and cut into individual semiconductor chips 1 a on which the surface structure of the device is formed.

  Specifically, for example, the semiconductor wafer 1 is diced and cut into individual semiconductor chips 1a as follows. In the semiconductor wafer 1, as shown in FIG. 1, the surface structure of the device is formed on the front surface side of the semiconductor wafer 1 for each semiconductor chip formation region 1b. The semiconductor chip formation regions 1b are arranged in a matrix at regular intervals, for example. Marks such as dicing lines 1c are formed between adjacent semiconductor chip formation regions 1b.

  The back surface of the semiconductor wafer 1 is subjected to back grinding or silicon etching so that the semiconductor wafer 1 is thinned to a predetermined thickness, and a semiconductor layer and electrodes on the back surface side are formed. The semiconductor wafer 1 may be a wafer having a flat back surface, or a rib wafer leaving an outer peripheral portion (rib portion) on the back surface side.

  The adhesive sheet 2 is attached to the back side of the semiconductor wafer 1 thinned as described above. The adhesive sheet 2 has a function of avoiding problems such as scattering of the semiconductor chip 1a separated by dicing. FIG. 1 shows a state where an adhesive sheet 2 is attached to the back side of the semiconductor wafer 1.

  The pressure-sensitive adhesive sheet 2 is affixed to the dicing frame 3 in advance, and the semiconductor wafer 1 is fixed to the dicing frame 3 by affixing the semiconductor wafer 1 to the pressure-sensitive adhesive sheet 2.

  Next, the semiconductor wafer 1 is diced from the front surface side of the semiconductor wafer 1 along the dicing line 1c. At this time, dicing is performed so that the notch due to dicing does not penetrate the adhesive sheet 2. Thereby, as shown in FIG. 2, the semiconductor wafer 1 is cut into individual semiconductor chips 1a.

  In addition, you may provide the process of weakening this adhesive force after the completion | finish of the cutting process with respect to the semiconductor wafer 1 according to the performance of the adhesive force of an adhesive sheet. In the step of weakening the adhesive strength, heating is performed or ultraviolet rays are irradiated from the back side according to the characteristics of the adhesive layer of the adhesive sheet.

  The thickness of the pressure-sensitive adhesive sheet 2 is desirably 20 μm or more and 200 μm or less, for example. The reason is that when the thickness of the pressure-sensitive adhesive sheet 2 exceeds 200 μm, the rigidity of the pressure-sensitive adhesive sheet 2 increases, and when the semiconductor chip 1a is taken up (pick up) from the pressure-sensitive adhesive sheet 2 by the semiconductor manufacturing apparatus according to the embodiment, This is because, as will be described later, the pressure-sensitive adhesive sheet 2 is hardly deformed along a groove provided in the holding stage, and the pressure-sensitive adhesive sheet 2 cannot be peeled from the semiconductor chip 1a.

  Since the semiconductor chip 1a is attached to the adhesive sheet 2, the semiconductor chip 1a is picked up and separated from the adhesive sheet 2 by a semiconductor manufacturing apparatus according to an embodiment described later. That is, the semiconductor manufacturing apparatus according to the embodiment is a pickup device that picks up the semiconductor chip 1 a attached to the adhesive sheet 2 from the adhesive sheet 2.

  Next, a configuration of a semiconductor manufacturing apparatus (hereinafter referred to as a pickup apparatus) according to the embodiment will be described. FIG. 3 is a perspective view schematically showing a main part of the semiconductor manufacturing apparatus according to the embodiment. FIG. 4 is a cross-sectional view schematically showing a main part of the semiconductor manufacturing apparatus according to the embodiment. FIG. 5 is a cross-sectional view illustrating a state after the semiconductor chip is placed on the semiconductor manufacturing apparatus according to the embodiment. As shown in FIGS. 3 to 5, the holding stage 10 of the pickup device includes a first stage 11 on which the semiconductor chip 1 a is placed via the adhesive sheet 2, a second stage 12 that supports the first stage 11, A vacuuming pipe 13 for evacuating the holding stage 10 and a contact prevention plate 31 for preventing the semiconductor chips 1a placed on the first stage 11 from contacting each other are provided.

  On the surface of the first stage 11 on which the semiconductor chip 1 a is placed (hereinafter referred to as the upper surface), a plurality of grooves 21, protrusions 22 composed of side walls of adjacent grooves 21, and grooves 21 A connected vent hole 14 is provided. The first stage 11 has, for example, a circular planar shape. The first stage 11 has, for example, a side wall 12b of the second stage 12 so as to close the opening 12c of the second stage 12 having a cylindrical side wall 12b closed on one side (hereinafter referred to as a bottom surface) 12a. It is supported by.

  The first stage 11 is supported on the side wall 12b of the second stage 12 with the surface opposite to the upper surface of the first stage 11 (hereinafter referred to as the lower surface) separated from the bottom surface 12a of the second stage 12. Has been. Further, the side surface of the first stage 11 is in contact with the side wall 12b of the second stage 12 so that there is no gap. As a result, a space 15 for evacuation surrounded by the first stage 11 and the second stage 12 is formed in the holding stage 10.

  This vacuuming space 15 is formed so as to connect the air hole 14 provided in the first stage 11 and the pipe 13 provided in the second stage 12. The vent hole 14 is formed so as to penetrate the first stage 11 from the bottom of the groove 21 formed on the upper surface of the first stage 11 and connect the groove 21 and the space 15 for vacuuming. At least one vent hole 14 is provided in the first stage 11.

  For example, the pipe 13 penetrates the side wall 12 b of the second stage 12 and is exposed to the outside of the second stage 12. A portion of the pipe 13 exposed to the outside of the second stage 12 is connected to a pressure reducing means (not shown) such as a vacuum device via a valve (not shown). By performing vacuuming by the decompression means, an air flow (solid arrow) 16 passing through the vent hole 14, the vacuuming space 15 and the pipe 13 is formed, and the air on the upper surface side of the first stage 11 is sucked. The

  As will be described later, the semiconductor chip 1a is placed on the upper surface of the first stage 11 with the surface of the semiconductor chip 1a to which the adhesive sheet 2 is attached facing down (on the first stage 11 side). For this reason, when vacuuming is performed by the decompression unit, the space surrounded by the adhesive sheet 2 and the groove 21 of the first stage 11 (hereinafter referred to as a closed space) is decompressed. Thereby, the adhesive sheet 2 is deformed along the side wall of the groove 21, and the portion of the adhesive sheet 2 facing the groove 21 is peeled off from the semiconductor chip 1a.

The decompression unit decompresses the closed space surrounded by the adhesive sheet 2 formed when the semiconductor chip 1 a is placed on the upper surface of the first stage 11 via the adhesive sheet 2 and the groove 21 of the first stage 11. . Then, the decompression unit deforms the pressure-sensitive adhesive sheet 2 attached to the semiconductor chip 1 a so as to follow the inner wall of the groove 21. Specifically, the decompression unit closes the contact portion between the semiconductor chip 1a and the adhesive sheet 2 until only the portion corresponding to the end portion (hereinafter referred to as the apex portion) of the protrusion 22 on the semiconductor chip 1a side. Depressurize the space.

  The contact prevention plate 31 is a plate-like member having a flat surface facing the upper surface of the first stage 11, for example. The contact prevention plate 31 has a size facing at least all the semiconductor chips 1 a mounted on the first stage 11. The contact prevention plate 31 is made of a material that does not cause chipping in the contacted semiconductor chip 1a. For example, the contact prevention plate 31 may be a member having a two-layer structure in which acrylic rubber, nitrile rubber, fluorine-based rubber, silicon rubber, or the like is attached to the side in contact with the semiconductor chip 1a.

  The contact prevention plate 31 is supported so as to be movable, and the upper surface of the first stage 11 and the upper surface of the first stage 11 are placed at a predetermined position above the first stage 11 before the decompression of the vacuuming space 15 is started by the decompression means. They are arranged at a predetermined interval x. The flat surface of the contact prevention plate 31 faces the main surface of the semiconductor chip 1 a placed on the first stage 11. The contact prevention plate 31 is held at a predetermined position above the first stage 11 at least while the vacuuming space 15 is decompressed by the decompression means. The contact prevention plate 31 receives the contact of the lifted end of the semiconductor chip 1a when the end of the semiconductor chip 1a is lifted, and suppresses the lift of the semiconductor chip 1a. To prevent contact.

  Specifically, the contact prevention plate 31 is disposed at a predetermined distance x from the upper surface of the first stage 11, and one end of the semiconductor chip 1 a tilted with respect to the first stage 11 by lifting one end. The inclination angle (hereinafter referred to as the inclination angle of the semiconductor chip 1a) θ with respect to the one stage 11 is suppressed to less than a predetermined angle. The inclination angle θ of the semiconductor chip 1 a is an angle formed between the back surface (the surface on the adhesive sheet 2 side) of the semiconductor chip 1 a and the top surface of the first stage 11. The condition of the predetermined distance x between the contact prevention plate 31 and the upper surface of the first stage 11 for preventing adjacent semiconductor chips 1a from contacting each other and the condition of the inclination angle θ of the semiconductor chip 1a will be described later.

  On the other hand, when the semiconductor chip 1a is picked up by a collet (not shown), which will be described later, the contact prevention plate 31 is moved to a position that does not hinder the pick-up operation of the semiconductor chip 1a by the collet. The position that does not interfere with the pick-up operation of the semiconductor chip 1 a by the collet is, for example, a position where the flat surface of the contact prevention plate 31 is separated from the upper surface of the first stage 11. Specifically, the position where the pick-up operation of the semiconductor chip 1a by the collet is not hindered is, for example, a position where the flat surface of the contact prevention plate 31 and the upper surface of the first stage 11 are substantially vertical. This is a position where the flat surface and the upper surface of the first stage 11 do not face each other. The movement of the contact prevention plate 31 to a predetermined position above the first stage 11 or a position away from the upper surface of the first stage 11 is performed by a moving means (not shown), for example.

  A collet for picking up the semiconductor chip 1 a is provided above the holding stage 10. The collet sucks and adsorbs the semiconductor chip 1a and picks up the semiconductor chip 1a after the closed space surrounded by the adhesive sheet 2 and the groove 21 of the first stage 11 is decompressed by the decompression means. Specifically, the collet sucks and picks up the semiconductor chip 1a after the pressure-sensitive adhesive sheet 2 is deformed until the contact portion between the semiconductor chip 1a and the pressure-sensitive adhesive sheet 2 is only a portion corresponding to the protrusion 22.

  The collet is preferably arranged at a predetermined interval h from the semiconductor chip 1a held on the protrusion 22 of the first stage 11 via the adhesive sheet 2. The reason is that the semiconductor chip 1a can be picked up without pressing the collet against the semiconductor chip 1a, and the element structure and the like formed on the surface of the semiconductor chip 1a can be prevented from being damaged.

  Further, the pickup device may include a heating means (not shown) for heating the adhesive sheet 2. By heating the adhesive sheet 2 by the heating means, the adhesive sheet 2 is easily deformed. Specifically, the heating unit may be, for example, a heater that heats the adhesive sheet 2 when the vacuuming space 15 is depressurized by the depressurizing unit.

  The control of the holding stage 10, the contact prevention plate 31, the moving means, the decompression means, the collet, and the heating means constituting the pickup apparatus is performed by, for example, storing programs and data recorded on a ROM, RAM, magnetic disk, optical disk, etc. in the pickup apparatus. It is performed by the CPU executing a predetermined program.

  Next, the groove 21 and the protrusion 22 of the first stage 11 will be described in detail. FIG. 6 is a bird's-eye view schematically showing a main part of the semiconductor manufacturing apparatus according to the embodiment. FIG. 6 shows an enlarged view of a portion 11a of the first stage 11 shown in FIG. As shown in FIG. 6, the groove 21 includes a plurality of first groove portions 21 a provided at predetermined intervals, and second groove portions 21 b orthogonal to the first groove portions 21 a and provided at predetermined intervals. . For example, the first and second groove portions 21 a and 21 b are provided at a depth that does not reach the lower surface of the first stage 11 from the upper surface of the first stage 11.

The interval between the adjacent first groove portions 21a and the interval between the adjacent second groove portions 21b is preferably equal to or less than the length of the short side of the rectangular semiconductor chip 1a. The reason is that the short side of the semiconductor chip 1 a can be held by at least two protrusions 22. First and second groove portions 21
The cross-sectional shapes of a and 21b are an inverted triangular shape in which the width gradually decreases in the depth direction of the first stage 11, or a rectangular shape in which the width is substantially equal in the depth direction of the first stage 11. Is preferred. The reason is that when the first and second groove portions 21 a and 21 b are formed on the upper surface of the first stage 11, it is easy to process.

  A plurality of protrusions 22 are provided on the upper surface of the first stage 11 by a plurality of first and second groove portions 21 a and 21 b, and hold the semiconductor chip 1 a via the adhesive sheet 2. The protrusion 22 has a truncated pyramid shape. A flat surface on which the semiconductor chip 1a is in surface contact is provided at an end (vertex portion) 22a of the protrusion 22 on the semiconductor chip 1a side. The apex 22a of the protrusion 22 is a flat surface parallel to, for example, the back surface of the semiconductor chip 1a held on the upper surface of the first stage 11, and is in surface contact with the surface of the semiconductor chip 1a on the first stage 11 side. .

  The protrusion 22 may have any shape that can be picked up without tilting the semiconductor chip 1a on the protrusion 22 by a collet (not shown) that sucks and picks up the semiconductor chip 1a. Specifically, the shape of the protrusion 22 is not limited to a truncated pyramid shape, and may be, for example, a pyramid shape or a cubic shape. When the shape of the protrusion 22 is a pyramid, the apex 22a of the protrusion 22 makes point contact with the semiconductor chip 1a. Each protrusion 22 is provided at the same height such that each vertex 22a is located in the same plane.

  The surface area of the apex 22a of the protrusion 22 is determined by, for example, the suction force of the collet that picks up the semiconductor chip 1a held on the apex 22a of the protrusion 22 via the adhesive sheet 2. Specifically, the adhesive force between the semiconductor chip 1a and the adhesive sheet 2 when only the adhesive sheet 2 between the semiconductor chip 1a and the apex portion 22a of the protrusion 22 is attached to the semiconductor chip 1a. However, the surface area of the apex portion 22a of the protruding portion 22 is determined so that the contact strength is such that the semiconductor chip 1a can be picked up by the collet.

  Next, conditions for preventing adjacent semiconductor chips 1a from contacting each other will be described. FIG. 7 is a cross-sectional view showing the semiconductor chip placed on the holding stage of the semiconductor manufacturing apparatus according to the embodiment. FIG. 8 is a cross-sectional view showing a state where adjacent semiconductor chips shown in FIG. 7 are in contact with each other. FIG. 7 is an enlarged view showing a part of the first stage 11 on which the semiconductor chip 1a is placed as shown in FIG. In FIG. 8, in order to clarify the inclination angle θ of the semiconductor chip 1a, the semiconductor chip 1a is illustrated with dimensions different from those in FIG.

  As shown in FIG. 7, the semiconductor chip 1 a is placed on the apex portion 22 a of the plurality of protrusions 22 via the adhesive sheet 2 by being placed with the surface on which the adhesive sheet 2 is attached facing down. It comes into contact. Thereby, the closed space 23 surrounded by the groove | channel 21 (1st, 2 groove part 21a, 21b) of the adhesive sheet 2 and the 1st stage 11 is formed. In this state, since the closed space 23 is depressurized by the depressurizing means, the pressure-sensitive adhesive sheet 2 is deformed along the side wall of the groove 21, and a portion facing the groove 21 of the pressure-sensitive adhesive sheet 2 is peeled off from the semiconductor chip 1 a. The semiconductor chip 1a is almost peeled from the adhesive sheet 2.

  As shown in FIG. 8, when adjacent semiconductor chips 1a are tilted at the same tilt angle with respect to the first stage 11 with the opposite end portions as fulcrums so that the opposing upper end portions are in contact with each other. If the inclination angle θ is smaller than the inclination angle, the adjacent semiconductor chips 1a are not in contact with each other. For this reason, the condition of the inclination angle θ of the semiconductor chips 1a so that the adjacent semiconductor chips 1a do not contact each other is expressed by the following equation (3). The semiconductor chip 1a is cut into individual semiconductor chips 1a by dicing so that the length a of one side of the rectangular semiconductor chip 1a, the thickness b of the semiconductor chip 1a, and the interval c between adjacent semiconductor chips 1a are obtained. .

  The contact prevention plate 31 has a predetermined distance x with respect to the first stage 11 so that the end of the semiconductor chip 1a on the side where the semiconductor chip 1a is lifted is in contact at a position where the inclination angle θ of the semiconductor chip 1a satisfies the above expression (3). It is arranged with a gap. For this reason, the contact prevention plate 31 can suppress the floating of the end portion of the semiconductor chip 1a so as to satisfy the expression (3), and the adjacent semiconductor chips 1a can be prevented from contacting each other. Therefore, the condition of the distance x between the contact prevention plate 31 and the first stage 11 satisfying the above expression (3) is expressed by the following expression (4).

  From the above formulas (3) and (4), the distance x between the contact prevention plate 31 and the first stage 11 for preventing the semiconductor chips 1a from contacting each other is expressed by the following formula (5).

  For example, when the length a of one side of the semiconductor chip 1a is 10 mm, the thickness b of the semiconductor chip 1a is 100 μm, and the distance c between adjacent semiconductor chips 1a is 30 μm, The distance x between the contact prevention plate 31 and the first stage 11 for preventing the chips 1a from contacting each other is less than 1.6 mm. When the rectangular semiconductor chip 1a has a long side and a short side, the length a of one side of the semiconductor chip 1a may be, for example, a long contact with the adjacent semiconductor chip 1a at a small inclination angle θ. The length of the edge may be applied. In this way, the contact prevention plate 31 is disposed with a gap x between the contact prevention plate 31 and the first stage 11 so as to satisfy the above equation (5), and an inclination angle θ satisfying the above equation (3) Thus, the semiconductor chip 1a has a function of suppressing lifting of the end portion of the semiconductor chip 1a.

  Next, a method for picking up the semiconductor chip 1a by the pickup device according to the embodiment will be described. 9 to 12 are cross-sectional views sequentially illustrating the operation of the semiconductor manufacturing apparatus according to the embodiment. 9 to 12 show one semiconductor chip 1a placed on the upper surface of the first stage 11 of the holding stage 10 as shown in FIG. First, as shown in FIG. 9, the semiconductor chip 1 a fixed to the dicing frame 3 is placed on the upper surface of the first stage 11 with the surface on which the adhesive sheet 2 is attached facing down. The semiconductor chip 1 a placed on the first stage 11 is in contact with the apex portions 22 a of the plurality of protrusions 22 via the adhesive sheet 2. And the closed space 23 enclosed by the adhesive sheet 2 and the groove | channel 21 (1st, 2nd groove part 21a, 21b) of the 1st stage 11 is formed.

  Next, as shown in FIG. 10, the contact prevention plate 31 is moved to a predetermined position above the first stage 11 by the moving means. The contact prevention plate 31 is disposed with a predetermined distance x from the upper surface of the first stage 11 so as to satisfy the above formula (5). As a result, the flat surface of the contact prevention plate 31 faces the main surfaces of all the semiconductor chips 1a placed on the first stage 11 with a predetermined interval. The timing of moving the contact prevention plate 31 above the first stage 11 may be before the semiconductor chip 1a is placed on the first stage 11, or the semiconductor chip 1a is placed on the first stage 11. It may be after.

  Next, the closed space 23 surrounded by the pressure-sensitive adhesive sheet 2 and the groove 21 of the first stage 11 is decompressed by the decompression means (not shown) through the vent hole 14. As a result, a negative pressure is generated in the portion of the adhesive sheet 2 attached to the semiconductor chip 1 a that faces the groove 21, and only the adhesive sheet 2 is deformed along the inner wall of the groove 21. For this reason, the closed space 23 surrounded by the adhesive sheet 2 and the groove 21 of the first stage 11 is almost eliminated. In this way, the portion of the pressure-sensitive adhesive sheet 2 facing the groove 21 is peeled from the semiconductor chip 1a. Thereby, the semiconductor chip 1a and the adhesive sheet 2 are in close contact with each other only at the portion corresponding to the apex portion 22a of the protrusion 22, and the adhesive sheet 2 is almost peeled from the semiconductor chip 1a. Therefore, the close contact between the semiconductor chip 1a and the pressure-sensitive adhesive sheet 2 can be lowered to such an extent that the semiconductor chip 1a can be sucked only by the suction force of the collet.

  At this time, even if the semiconductor chip 1a whose adhesion to the adhesive sheet 2 is lowered is inclined with respect to the first stage 11, the contact prevention plate 31 is above the first stage 11 (5). Since the semiconductor chip 1a is disposed at a predetermined interval x so as to satisfy the equation, the end of the semiconductor chip 1a on the raised side contacts the contact prevention plate 31. As a result, the tilt angle θ of the semiconductor chip 1a tilted with respect to the first stage 11 becomes a value satisfying the above expression (3). For this reason, even if the semiconductor chip 1a is inclined with respect to the first stage 11, the semiconductor chip 1a does not come into contact with another adjacent semiconductor chip 1a. Accordingly, no chipping occurs in the semiconductor chip 1a.

  Further, the semiconductor chip 1a that is inclined with respect to the first stage 11 returns to a state where it is not inclined with respect to the first stage 11 by contacting the contact prevention plate 31 (inclination angle θ = 0). . Thereafter, the contact preventing plate 31 is moved to a position away from the first stage 11 by the moving means. Next, as shown in FIG. 11, the collet 41 is moved above the semiconductor chip 1a with a predetermined interval h from the semiconductor chip 1a. Next, the semiconductor chip 1 a is sucked and sucked by the collet 41. Since the adhesive force between the semiconductor chip 1a and the adhesive sheet 2 is sufficiently low, the distance h between the collet 41 and the semiconductor chip 1a can be set to 1 mm or less, for example. Thereby, the semiconductor chip 1a can be picked up only by the suction force of the collet 41.

  It is preferable to pick up the semiconductor chip 1a without pressing the collet 41 against the semiconductor chip 1a. For this reason, the interval h between the collet 41 and the semiconductor chip 1a may be an interval at which the collet 41 is not pressed against the semiconductor chip 1a, and the collet 41 and the semiconductor chip 1a may be in contact with each other. That is, the distance h between the collet 41 and the semiconductor chip 1a is preferably 0 mm or more. By setting the interval h between the collet 41 and the semiconductor chip 1a to be 0 mm or more, it is possible to prevent the element structure and the like formed on the surface of the semiconductor chip 1a from being damaged.

  Further, while the semiconductor chip 1a is sucked by the collet 41, the closed space 23 is continuously decompressed by the decompression means. Thereby, the adhesive sheet 2 peeled from the semiconductor chip 1a is maintained in contact with the inner wall of the groove 21, so that the adhesive sheet 2 sticks to the collet 41 when the semiconductor chip 1a is sucked by the collet 41. There is no. In this way, the semiconductor chip 1a is picked up from the first stage 11 as shown in FIG.

  When the pickup device includes a heating unit, the closed space 23 may be decompressed by the decompression unit while heating the adhesive sheet 2 by the heating unit. By heating the adhesive sheet 2 by the heating means, the adhesive sheet 2 is easily deformed. For this reason, the adhesive sheet 2 is easily deformed along the inner wall of the groove 21 of the first stage 11 and peeled off from the semiconductor chip 1a.

  As described above, according to the embodiment, while the closed space surrounded by the adhesive sheet and the groove of the first stage is depressurized by the depressurizing means, the predetermined interval is set at a predetermined position above the first stage. Since the contact prevention plate is arranged with a gap, even if the semiconductor chip is inclined with respect to the first stage, the inclination angle of the semiconductor chip can be suppressed to the extent that it does not contact other adjacent semiconductor chips. it can. Thereby, chipping and scratching of the semiconductor chips caused by the contact between adjacent semiconductor chips can be prevented. Therefore, the semiconductor chip can be peeled off from the adhesive sheet and picked up in a high quality state.

  Further, according to the embodiment, since the contact prevention plate faces the main surface of all the semiconductor chips placed on the first stage, it is possible to prevent chipping or scratches on all the semiconductor chips placed on the first stage. Can be prevented. In addition, according to the embodiment, when picking up a semiconductor chip with a collet, the contact prevention plate is moved to a position that does not interfere with the operation of the collet, and therefore, a collet that performs the same operation as a conventional pickup device can be used. it can. For this reason, it is not necessary to provide a special jig for picking up the semiconductor chip.

  Further, according to the above-described invention, the closed space surrounded by the pressure-sensitive adhesive sheet and the first stage groove is depressurized by the pressure reducing means, so that the portion facing the groove of the pressure-sensitive adhesive sheet is peeled off from the semiconductor chip, and the pressure-sensitive adhesive sheet The semiconductor chip can be held only at a plurality of apex portions via. For this reason, the adhesive force between the semiconductor chip and the adhesive sheet can be reduced to the extent that the semiconductor chip can be picked up only by the suction force of the suction means. Thereby, a semiconductor chip can be reliably peeled from an adhesive sheet and picked up. In addition, since the adhesion force between the semiconductor chip and the adhesive sheet can be reduced to the extent that the semiconductor chip can be picked up only by the suction force of the collet, when picking up the semiconductor chip by the suction means, a needle or the like as in the prior art There is no need to carry out the process of pushing up the semiconductor chip using. Therefore, it is possible to prevent the surface of the semiconductor chip from being damaged by a needle or the like. Thereby, a semiconductor chip can be peeled from an adhesive sheet and picked up in a high quality state.

  Furthermore, according to the above-described invention, the adhesion force between the semiconductor chip and the adhesive sheet can be reduced to the extent that the semiconductor chip can be picked up only by the suction force of the suction means. For this reason, the semiconductor chip can be reliably picked up by the suction force of the collet without pressing the collet against the semiconductor chip.

  Thus, the semiconductor chip on the first stage can be picked up without tilting the semiconductor chip with respect to the first stage and without causing chipping or cracking of the semiconductor chip. Therefore, the thinned semiconductor chip can be picked up by the pickup device according to the embodiment, and the thinned semiconductor chip can be safely transported.

  As described above, the present invention can provide the same effect even when a back electrode or the like is formed on the back surface side of the semiconductor wafer before the adhesive sheet is attached to the back surface of the thinned semiconductor wafer.

  As described above, the semiconductor manufacturing apparatus and the semiconductor manufacturing apparatus control method according to the present invention are useful when picking up a dicing cut semiconductor chip from an adhesive sheet and separating it into individual semiconductor chips.

DESCRIPTION OF SYMBOLS 1 Semiconductor wafer 1a Semiconductor chip 2 Adhesive sheet 3 Dicing frame 10 Holding stage 11, 12 Stages constituting the holding stage (first and second)
13 Piping for vacuuming 14 Ventilation hole 15 Space for vacuuming 16 Air flow 21 Groove 22 Protruding part 22a Apex part of protruding part 23 Closed space 31 Contact prevention plate

Claims (8)

A semiconductor manufacturing apparatus that picks up a semiconductor chip cut by dicing from an adhesive sheet,
A stage on which the semiconductor chip is placed;
A groove provided on a surface on which the semiconductor chip of the stage is placed;
Formed by an end of the groove on the opening side, and an apex for holding the semiconductor chip via the adhesive sheet;
At least one vent hole provided in the stage and connected to the groove;
Depressurization that decompresses the pressure-sensitive adhesive sheet attached to the stage-side surface of the semiconductor chip placed on the stage and the space surrounded by the groove provided in the stage through the vent hole Means,
A suction means for sucking and picking up the semiconductor chip held at the apex portion by decompressing the space by the decompression means;
A contact prevention plate disposed above the stage at a predetermined interval and preventing the semiconductor chips from contacting each other when the space is decompressed by the decompression unit;
A semiconductor manufacturing apparatus comprising:   Before the space is decompressed by the decompression means, the contact prevention plate is moved above the stage, and the operation of the suction means is not hindered before the semiconductor chip is picked up by the suction means. The semiconductor manufacturing apparatus according to claim 1, further comprising moving means for moving the contact prevention plate to a position. The stage on which the semiconductor chip having a rectangular shape that is cut by dicing so as to have a length a of one side of the semiconductor chip, a thickness b of the semiconductor chip, and an interval c between the adjacent semiconductor chips is placed. 3. The semiconductor manufacturing apparatus according to claim 1, wherein the contact prevention plate is disposed at a predetermined interval x satisfying the following expression (1):

  The semiconductor manufacturing apparatus according to claim 1, wherein the contact prevention plate faces main surfaces of all the semiconductor chips placed on the stage. A method for controlling a semiconductor manufacturing apparatus that picks up a semiconductor chip cut by dicing from an adhesive sheet,
The mounting step of mounting the semiconductor chip on the surface provided with the groove of the stage, with the surface on the side where the adhesive sheet is affixed on the stage side,
Depressurizing step of depressurizing the space surrounded by the groove and the adhesive sheet, and holding the semiconductor chip at the apex formed by the end of the groove on the opening side;
A suction step of sucking and picking up the semiconductor chip held at the apex portion by a suction means;
Including
In the decompression step, the semiconductor manufacturing apparatus control method is characterized in that the semiconductor chips are prevented from coming into contact with each other by a contact prevention plate disposed above the stage at a predetermined interval. A first moving step of moving the contact prevention plate above the stage before the pressure reducing step;
A second moving step of moving the contact prevention plate to a position not hindering the operation of the suction means after the placing step and before the suction step;
The method for controlling a semiconductor manufacturing apparatus according to claim 5, further comprising: In the placing step, the rectangular semiconductor chip cut by dicing so as to have a length a of one side of the semiconductor chip, a thickness b of the semiconductor chip, and an interval c between the adjacent semiconductor chips is obtained. Placed on the stage,
7. The semiconductor manufacturing apparatus according to claim 5, wherein in the first moving step, the contact prevention plate is disposed above the stage with a predetermined interval x satisfying the following expression (2). Control method.

  The method of controlling a semiconductor manufacturing apparatus according to claim 5, wherein the contact prevention plate faces main surfaces of all the semiconductor chips placed on the stage.

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