JP2010103238A - Device for manufacturing semiconductor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology which measures electric characteristics of a wafer accurately, and prevents a damage of the wafer. <P>SOLUTION: When a probe needle 18 is brought into contact with a position corresponding to a groove 6 of a stage 4 upon inspection using the probe needle 18, a wafer support member 10 is pressed up to a direction of a mounting face 4a of the stage 4 by a moving mechanism 16. Thus, the mounting face 4a and the wafer support member 10 form the same plane to support a wafer 20. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a semiconductor manufacturing apparatus. In particular, it relates to an apparatus for testing the electrical properties of a wafer.

2. Description of the Related Art A semiconductor manufacturing apparatus that tests electrical characteristics of a wafer using a test jig such as a probe is known. When testing a wafer using this type of semiconductor manufacturing apparatus, air is sucked from a groove provided in the stage, and the wafer is sucked and fixed to the stage. Then, a test jig such as a probe is pressed against the wafer attracted and fixed to the stage, and the electrical characteristics of the wafer are measured. The measurement of the electrical characteristics is performed at a plurality of portions of the wafer while changing the position of the probe. For this reason, a probe may be pressed on the part corresponding to the position of the groove | channel provided in the stage. In such a case, the wafer may be damaged by the pressure from the probe.
As a conventional technique for solving such a problem, a technique disclosed in Patent Document 1 is known. In Patent Document 1, a probe test is performed using a stage in which a buffer material is disposed on a wafer mounting surface.

JP 11-337580 A

In the technique of Patent Document 1, an elastically deformable material such as rubber is disposed between the wafer and the stage so as to cover the entire surface of the wafer, and this functions as a cushioning material to prevent the wafer from being damaged to some extent. Can do. However, the buffer material is formed with suction holes (suction holes for sucking air) for sucking the wafer to the buffer material. For this reason, when the probe is pressed to a position corresponding to the suction hole, the wafer may be damaged. Further, in order to accurately measure the electrical characteristics of the wafer, it is desirable that no member (that is, a buffer material) that generates electrical resistance be interposed between the wafer and the stage. For this reason, in this type of semiconductor manufacturing apparatus, there is a need for a technique that can accurately measure electrical characteristics and can prevent damage to the wafer during testing.
An object of this invention is to provide the technique which can measure the electrical property of a wafer accurately and can prevent damage to a wafer.

  A semiconductor manufacturing apparatus according to the present invention includes a stage including a mounting surface on which a wafer is mounted and a groove formed on the mounting surface, air suction means for sucking air in the groove, and different in the groove. A wafer support member that is disposed at each position and is movable in the groove height direction, and a top surface of the wafer support member from the first position where the top surface of the wafer support member is retracted from the placement surface. A moving mechanism for moving the wafer support member is provided at a second position on the same plane. This apparatus is characterized in that when the moving mechanism moves at least one of the plurality of wafer support members to the second position, the remaining wafer support members are in the first position.

  In this semiconductor manufacturing apparatus, wafer support members are disposed at different positions in grooves formed on the stage. The moving mechanism can move at least one of the plurality of wafer support members such that the upper surface thereof is flush with the mounting surface. That is, the upper surface of the wafer support member and the stage mounting surface are positioned on the same plane by pushing the predetermined wafer support member disposed in the groove in the groove height direction (upward). be able to. At this time, the remaining wafer support members are maintained in a state of being retracted from the placement surface. For this reason, when a probe contacts the position corresponding to a groove | channel, the wafer support member arrange | positioned at the place can be moved, and a wafer can be supported. Further, since the remaining wafer support members are retracted from the placement surface, the wafer can be adsorbed to the placement surface. Therefore, damage to the wafer can be prevented while adsorbing the wafer to the mounting surface. In addition, since no cushioning material or the like is provided between the wafer and the mounting surface, such an intermediate member becomes an electrical resistance and does not cause a problem that the measurement of the electrical characteristics of the wafer is affected.

  According to the present invention, it is possible to prevent the wafer from being damaged during the test of the electrical characteristics of the wafer and to accurately measure the electrical characteristics of the wafer.

The technical features of the following examples are listed.
(Feature 1) A means for changing the relative positional relationship between the stage and the moving mechanism is provided.
(Feature 2) The wafer support member penetrates the stage, the upper surface forms part of the bottom surface of the groove, and the wafer support member protrudes from the back side of the stage by the same length as the height of the groove. .
(Feature 3). At the end of the wafer support member on the back side of the stage, when the wafer support member is moved in the placement surface direction (direction from the first position toward the second position) by the moving mechanism, the upper surface of the wafer support member is placed on the stage. A stopper that prohibits the protrusion from the mounting surface is provided.
(Feature 4) Means for retracting the wafer support member in the rear surface direction of the stage (direction from the second position toward the first position) is provided.

(First embodiment)
A semiconductor manufacturing apparatus according to a first embodiment embodying the present invention will be described with reference to FIGS. FIG. 1 is a schematic plan view of the semiconductor manufacturing apparatus 2 of the first embodiment, and FIG. 2 is a cross-sectional view taken along the line II-II of the semiconductor manufacturing apparatus 2 of FIG. FIG. 3 is a diagram showing a state of a probing test using the semiconductor manufacturing apparatus 2 of the present embodiment.

  The semiconductor manufacturing apparatus 2 includes a stage 4. The stage 4 is connected to an arm (not shown) and can be moved by the arm. The stage 4 is made of a highly conductive material. An external tester is electrically connected to the stage 4. During the probing test, the electrical characteristics of the wafer 20 are measured by this tester. The stage 4 includes a mounting surface 4a for mounting a wafer. Grooves 6 are formed in a triple ring shape on the mounting surface 4a, and these triple ring-shaped grooves are connected by grooves extending in the radial direction from the center of the stage. A suction through-hole 8 is provided at the bottom of the groove 6 extending in the radial direction at the center of the stage 4. The suction through-hole 8 is connected to a suction mechanism (suction pump) 14 that sucks air in the groove 6. The stage 4 sucks the air in the groove 6 by the suction mechanism 14, thereby vacuum-sucking and fixing the wafer 20 (see FIG. 3) placed on the placement surface 4a. The shape of the groove 6 is not limited to the pattern shown in FIG.

A plurality of through holes are formed at different positions on the bottom of the groove 6. The position where the through hole is formed corresponds to the position where the wafer 20 is pressed by the probe needle 18 during the probing test. Wafer support members 10 are slidably inserted into the respective through holes. The wafer support member 10 includes a head 10a and a shaft portion 10b extending from the head 10a. Each of the plurality of through holes of the stage 4 is formed corresponding to the shapes of the head 10 a and the shaft portion 10 b of the wafer support member 10. Further, the head 10 a of the wafer support member 10 of this embodiment is formed of the same material as that of the stage 4, and has the same conductivity as that of the stage 4. It is not necessary to form the entire head 10a from the same material as that of the stage 4, and at least a portion in contact with the wafer 20 and the stage 4 should have the same conductivity as the mounting surface 4a of the stage 4. That's fine.
In order to maintain the accuracy of the probing test, it is necessary to keep the potential of the stage 4 constant when the wafer support member 10 supports the wafer together with the stage 4. For this reason, it is not preferable that the stage 4 is electrically connected to a cam member 12 described later. For this reason, at least a part of the wafer support member 10 below the upper surface of the head 10a is formed of a highly insulating material. For example, a part of the shaft portion 10b can be formed of an insulator. With such a configuration, the head 10a and the cam member 12 can be insulated.

Each wafer support member 10 can move independently in the groove 6 in the vertical direction of FIG. 2 (that is, the height direction of the groove 6). When no force is applied to the wafer support member 10 from the outside (that is, when the upper surface of the wafer support member 10 is in a position retracted from the mounting surface 4 a), the upper surface of the head 10 a is the bottom surface of the groove 6. It is located on the same plane (FIG. 2). From this state, the wafer support member 10 can move up and down to a height (see FIG. 3) where the upper surface of the head 10a is located on the same plane as the mounting surface 4a. In FIG. 1, the wafer support member 10 is not shown.
In the present embodiment, the wafer support member 10 is arranged corresponding to the position where the probe needle 18 presses the wafer 20 during the probing test, but the present invention is not limited to such a form. For example, as shown in FIG. 4, the wafer support member 10 may be disposed over the entire circumference of the groove 6. In the example shown in FIG. 4, the head 10 a of the wafer support member 10 extends in the circumferential direction of the groove 6. Although not shown, the shaft portion 10b is formed substantially at the center of the head 10a. With the above configuration, the wafer support member 10 can support the wafer regardless of the position in the groove 6 where the probe needle 18 presses the wafer. That is, the probing test can be satisfactorily performed regardless of the size of the wafer and the position where the probing test is performed on the wafer. Thereby, a plurality of types of wafers can be inspected with one apparatus.
Further, the present invention is not limited to the number and shape of the wafer support members 10 shown in FIGS. For example, the wafer support member 10 may be disposed in the groove 6 at a predetermined interval or may be continuously disposed. The position where the wafer support member 10 is disposed, the shape of the head 10a, and the like can be appropriately designed according to the content of the test performed on the wafer 20 (probing position, size of the probe needle 18).

A cam member 12 is disposed below the stage 4. A cam surface 16 is formed on the upper surface of the cam member 12. The cam surface 16 includes a flat top portion and an inclined surface inclined from the top portion to the reference upper surface of the cam member 12. By moving the stage 4 by an arm (not shown), the relative positional relationship between the stage 4 and the cam surface 16 can be changed. Similarly to the wafer support member 10, the cam member 12 is formed of a material having high insulation so as not to affect the electrical characteristics of the wafer 20.
A probe needle 18 is disposed above the cam surface 16. The positional relationship in the horizontal plane between the cam surface 16 and the probe needle 18 is fixed.

  As shown in FIG. 3, when a probing test is performed on the wafer 20 placed on the stage 4, a predetermined portion of the wafer 20 (for example, an electrode pad of each IC chip formed on the wafer 20). The probe needles 18 are sequentially pressed against each other. That is, in this test, the electrical characteristics of the wafer 20 are measured at a plurality of portions of the wafer 20 while changing the position where the probe needle 18 contacts. This inspection is performed by sucking and fixing the wafer 20 to the stage 4 by sucking the air in the groove 6 in order to prevent the wafer 20 from warping due to the displacement of the measurement position or the pressing of the probe needle 18. Further, since the probe needle 18 is pressed against the wafer 20, pressure acts on the contact portion of the probe needle 18. For this reason, if the suction fixing groove 6 is located under the portion of the wafer 20 that the probe needle 18 contacts, and that portion is not supported from below, the wafer 20 may be damaged.

  In the semiconductor manufacturing apparatus 2 of the present embodiment, when the groove 6 is present under the portion of the wafer 20 with which the probe needle 18 is brought into contact, the wafer support member 10 is disposed in that portion. Further, the positional relationship in the horizontal plane between the probe needle 18 and the cam surface 16 of the cam member 12 does not change. For this reason, when the stage 4 is moved in the horizontal direction and the probe needle 18 is positioned at the corresponding portion, the cam surface of the cam member 12 is also positioned below the corresponding portion. Therefore, when pressing the probe needle 18, first, the stage 4 is moved in the horizontal direction by the operation of the arm, and the probe needle 18 and the cam surface 16 are positioned with respect to the wafer 20. Next, the stage 4 is moved toward the cam member 12. As a result, the lower end of the wafer support member 10 contacts the cam surface 16 of the cam member 12. When the stage 4 is further moved downward, the head 10a of the wafer support member 10 is raised in the direction of the mounting surface 4a. When the top of the cam surface 16 of the cam member 12 comes into contact with the lower surface of the stage 4 (as shown in FIG. 3), the upper surface of the head 10a is pushed up to the same plane as the mounting surface 4a and contacts the back surface of the wafer 20. To do. At this time, the upper surface of the head 10a is also in contact with the mounting surface 4a in the peripheral portion thereof. As a result, the wafer 20 is connected to the tester via the head 10 a and the stage 4. In this state, the probe needle 18 presses the wafer 20, and the electrical characteristics of the wafer 20 are measured. When the measurement of the electrical characteristics is completed, the stage 4 moves in a direction away from the cam member 12 (that is, upward). Thereby, the wafer support member 10 moves to the state shown in FIG. 2 by its own weight. It should be noted that a spring mechanism may be provided in the groove 6 so that the wafer support member 10 is surely returned to the state shown in FIG. That is, the wafer support member 10 may be biased downward by a spring.

  As described above, when the probe needle 18 comes into contact with the wafer 20 while the wafer support member 10 supports the wafer 20 from below, the force that acts on the wafer 20 from the probe needle 18 can be received by the wafer support member 10. There is no problem such as breakage of the wafer 20. Further, even if the groove 6 is closed by the wafer support member 10, the entire groove 6 is not closed, so that the wafer 20 can be fixed to the stage 4 by suction. Thereby, it is possible to suitably prevent the wafer 20 from being displaced during the probing test. Further, since the wafer support member 10 and the cam member 12 are formed of an insulating material, even if the wafer support member 10 contacts the wafer 20, the electrical characteristics of the wafer 20 are not affected. According to the semiconductor manufacturing apparatus 2 of the present embodiment, it is possible to satisfactorily prevent the wafer 20 from being damaged during the probing test without affecting the electrical characteristics of the wafer 20.

(Modification of the first embodiment)
FIG. 5 shows a modification of the semiconductor manufacturing apparatus of the first embodiment. In the semiconductor manufacturing apparatus 30, a stopper 22 formed of a magnet is provided at the lower end of the shaft portion 10 b of each wafer support member 10. Further, a driving member 26 is disposed below the stage 4, and a magnet 24 is fixed to the upper surface of the driving member 26. The stopper 22 and the magnet 24 are formed with the same magnetic pole. That is, when the stage 4 moves and the wafer support member 10 is positioned on the magnet 24, the stopper 22 and the magnet 24 repel each other, and the head 10a is pushed upward by this magnetic force. That is, in the first embodiment, the height position of the wafer support member 10 is mechanically changed by the cam member 16, whereas in this embodiment, the height position of the wafer support member 10 is changed by the magnetic force of the magnet 24. It changes without contact.

  In the state shown in FIG. 5 (the state in which the wafer support member 10 is pushed up by the magnetic force of the magnet 24), the stopper 22 is in contact with the back surface of the stage 4, and the head 10a of the wafer support member 10 is at a height position (shown in FIG. 5). That is, it is prevented from being pushed up further than the mounting surface 4a. When the stage 4 is separated from the magnet 24, the magnetic repulsive force between the stopper 22 and the magnet 24 is reduced, and the wafer support member 10 returns to its original state by its own weight. Further, a pullback magnet having a magnetic pole opposite to the magnetic pole on the lower surface side of the stopper 22 may be further disposed around the magnet 24 on the upper surface of the driving member 26. According to this configuration, the head 10 a of the wafer support member 10 can be reliably moved to a position where it abuts against the bottom surface of the groove 6 by the attractive force generated between the stopper 22 and the pullback magnet.

The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. For example, you may provide a stopper in the lower end of the axial part 10b of the wafer support member 10 of 1st Example. In such a case, the stopper may not be a magnetic member.
In addition, the technology exemplified in this specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The schematic plan view of the semiconductor manufacturing apparatus of 1st Example. II-II sectional drawing of the semiconductor manufacturing apparatus of FIG. The figure showing the mode of the probing test using the semiconductor manufacturing apparatus of 1st Example. The figure which expands and shows a part of stage concerning the modification which deform | transformed the stage of the semiconductor manufacturing apparatus of FIG. The figure showing the modification of the semiconductor manufacturing apparatus of 1st Example.

Explanation of symbols

2, 30: Semiconductor manufacturing apparatus 4: Stage 6: Groove 8: Suction through hole 10: Wafer support member 10a: Head 10b: Shaft portion 12: Cam member 14: Suction mechanism 16: Cam surface 18: Probe needle 20: Wafer 22: Stopper 24: Magnet 26: Drive member

Claims (1)

A stage comprising a placement surface on which the wafer is placed, and a groove formed on the placement surface;
An air suction means for sucking air in the groove;
A wafer support member that is disposed at a different position in the groove and is movable in the groove height direction;
A moving mechanism for moving the wafer support member from a first position where the upper surface of the wafer support member is retracted from the placement surface to a second position where the upper surface of the wafer support member is flush with the placement surface;
The semiconductor manufacturing apparatus, wherein when the moving mechanism moves at least one of the plurality of wafer support members to the second position, the remaining wafer support members are in the first position.

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