Semiconductor manufacturing equipment

Abstract

To provide semiconductor manufacturing equipment capable of measuring the electrical characteristics of a semiconductor wafer even if there is an insulating layer on the backside of the semiconductor wafer.SOLUTION: Semiconductor manufacturing equipment according to the present embodiment comprises a stage that supports a semiconductor wafer. A probe card is positioned above the stage. A first electrode is made of conductive material and is movable on the stage from the outside to the center of the stage and can contact the sides of the semiconductor wafer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present embodiment relates to a semiconductor manufacturing apparatus. [Background technology]

[0002] In semiconductor manufacturing equipment, a stage on which a semiconductor wafer is placed may be electrically connected to the back surface of the semiconductor wafer.

[0003] However, when an insulating layer is formed on the back side of the semiconductor wafer, the stage cannot be electrically connected to the substrate of the semiconductor wafer, making it impossible to measure the electrical characteristics of the semiconductor wafer in the semiconductor manufacturing equipment.

[0004] On the other hand, when the insulating layer on the back side of the semiconductor wafer is removed, a difference occurs between the front and back stresses of the semiconductor wafer, causing the semiconductor wafer to warp, which makes it difficult to transport the semiconductor wafer during the semiconductor manufacturing process. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5489356 [Patent Document 2] JP 2010-40856 A [Patent Document 3] JP 2010-251632 A [Patent Document 4] Japanese Patent Application Publication No. 4-357848 [Patent Document 5] Japanese Utility Model Application Publication No. 01-097551 Summary of the Invention [Problem to be solved by the invention]

[0006] A semiconductor manufacturing apparatus capable of measuring electrical characteristics of a semiconductor wafer even if the semiconductor wafer has an insulating layer on the rear surface thereof. [Means for solving the problem]

[0007] The semiconductor manufacturing apparatus according to the present embodiment includes a stage for supporting a semiconductor wafer. A probe card is positioned above the stage. A first electrode is made of a conductive material and is movable on the stage from the outside to the center of the stage, and is capable of contacting a side surface of the semiconductor wafer. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a probing device according to a first embodiment. [Diagram 2] FIG. 4 is a flowchart showing an example of the operation of the probing device according to the first embodiment. [Diagram 3] FIG. 2 is a cross-sectional view showing a configuration example of a semiconductor wafer placed on a stage. [Figure 4] FIG. 2 is a cross-sectional view showing a configuration example of a semiconductor wafer placed on a stage. [Diagram 5] 11 is a cross-sectional view showing a manufacturing process of a semiconductor device after a semiconductor wafer inspection process. [Figure 6] 6 is a cross-sectional view showing a manufacturing process of the semiconductor device following FIG. 5. [Figure 7] 7 is a cross-sectional view showing a manufacturing process of the semiconductor device following FIG. 6. [Figure 8] 8 is a cross-sectional view showing a manufacturing process of the semiconductor device following FIG. 7. [Figure 9] 9 is a cross-sectional view showing a manufacturing process of the semiconductor device following FIG. 8. [Figure 10] FIG. 11 is a plan view showing an example of the configuration of a clamp electrode according to a second embodiment. [Figure 11] FIG. 11 is a plan view showing an example of the configuration of a clamp electrode according to a third embodiment. [Figure 12] 13 is a cross-sectional view showing a configuration example of a clamp electrode according to a fourth embodiment. FIG. [Figure 13] 13 is a cross-sectional view showing a configuration example of a clamp electrode according to a fifth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiment. The drawings are schematic or conceptual. In the specification and the drawings, the same elements are given the same reference numerals.

[0010] (First embodiment) 1 is a diagram showing an example of the configuration of a probing device according to a first embodiment. The probing device 1 is, for example, a semiconductor manufacturing device such as a semiconductor test device. The probing device 1 includes a stage 10, a probe card 20, a probe needle 21, clamp electrodes 30a and 30b, a stage driver 40, a clamp driver 50, a probe card driver 52, a transport arm driver 54, a controller 60, a measurement unit 70, and a transport arm 80.

[0011] The stage 10 is capable of placing and supporting a semiconductor wafer W. The stage 10 has a vacuum chuck function or an electrostatic chuck function for adsorbing the back surface of the semiconductor wafer. The semiconductor wafer W has power semiconductor elements such as an IGBT (Insulated Gate Bipolar Transistor), a HEMT (High Electron Mobility Transistor), a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or a diode. Therefore, the semiconductor wafer W has not only a front surface electrode but also a back surface electrode.

[0012] The probe card 20 is located above the stage 10 and includes probe needles 21 that come into contact with surface electrodes (electrode pads) of the semiconductor wafer W to be measured. The probe card 20 is controlled by the control unit 60 and can move in the X, Y, and Z directions. After the semiconductor wafer W is placed on the stage 10, the probe card 20 moves to bring the tips of the probe needles 21 into contact with any electrode pad of the semiconductor wafer W. The probe card 20 may be fixed, and the stage 10 may move in the X, Y, and Z directions. Either or both of the stage 10 and the probe card 20 may be movable.

[0013] Clamp electrodes 30a, 30b as first and second electrodes are movable on stage 10 from the outside of stage 10 toward the center. Clamp electrodes 30a, 30b approach semiconductor wafer W from both sides of semiconductor wafer W and can contact the side surfaces of semiconductor wafer W. Clamp electrodes 30a, 30b are made of a conductive material such as copper, aluminum, tungsten, etc. Clamp electrodes 30a, 30b may be movable in opposing directions (±X directions) so that both approach each other, or only one of them may be movable so that it approaches the other.

[0014] Clamp electrodes 30a, 30b contact the side surfaces of semiconductor wafer W, whereby clamp electrodes 30a, 30b function as back electrodes (e.g., drain electrodes) connected to the substrate of semiconductor wafer W. As a result, even if there is an insulating film on the back surface of semiconductor wafer W, the substrate of semiconductor wafer W can be electrically connected to measurement unit 70 via clamp electrodes 30a, 30b.

[0015] The thickness T30 of the clamp electrodes 30a, 30b in the direction perpendicular to the support surface of the stage 10 (Z direction) is smaller than the thickness Tw of the semiconductor wafer W. As a result, the clamp electrodes 30a, 30b are electrically connected only to the substrate of the semiconductor wafer W, and are not electrically connected to the semiconductor element formed in the surface region of the semiconductor wafer W. If the clamp electrodes 30a, 30b are connected to, for example, a drain electrode, the probe needle 21 can be connected to, for example, a source electrode or a gate electrode. This allows a voltage to be applied between the probe needle 21 and the clamp electrodes 30a, 30b to measure the electrical characteristics of the semiconductor element. Note that the thickness T30 of the clamp electrodes 30a, 30b may be equal to or larger than the thickness Tw of the semiconductor wafer W as long as the clamp electrodes 30a, 30b are not short-circuited to the semiconductor element.

[0016] The stage driving unit 40 moves and rotates the stage 10 under the control of the control unit 60 .

[0017] Under the control of the control unit 60, the clamp driving unit 50 moves the clamp electrodes 30a, 30b in the XY plane on the stage 10. This allows the clamp electrodes 30a, 30b to clamp the semiconductor wafer W from both sides and to be electrically connected to the semiconductor wafer W.

[0018] The probe card driving unit 52 moves the probe card 20 to above the semiconductor wafer W on the stage 10 and brings the probe needles 21 into contact with the semiconductor elements. The probe card 20 brings the probe needles 21 into contact with the semiconductor elements E of the semiconductor wafer W from above the stage 10.

[0019] The transfer arm driver 54 moves the transfer arm 80. The transfer arm 80 transfers a semiconductor wafer W from the outside and places it on the stage 10.

[0020] The control unit 60 controls the stage driving unit 40, the clamp driving unit 50, the probe card driving unit 52, and the transfer arm driving unit .

[0021] Measurement unit 70 is electrically connected to probe card 20 and clamp electrodes 30a, 30b, and applies power between probe needles 21 and clamp electrodes 30a, 30b. Furthermore, measurement unit 70 measures the electrical characteristics of the semiconductor elements of semiconductor wafer W obtained via probe card 20 and clamp electrodes 30a, 30b.

[0022] The control unit 60 and the measurement unit 70 may be configured, for example, as one and the same computer or as separate computers.

[0023] FIG. 2 is a flow chart showing an example of the operation of the probing device according to the first embodiment.

[0024] First, the transfer arm 80 transfers the semiconductor wafer W and places it on the stage 10 (S10).

[0025] 3 and 4 are cross-sectional views showing a configuration example of a semiconductor wafer W placed on the stage 10. The semiconductor wafer W includes a substrate S, a semiconductor element E, and a back surface insulating film I. The substrate S has a front surface F1, a back surface F2 opposite to the front surface F1, and a side surface F3 between the front surface F1 and the back surface F2.

[0026] The substrate S is made of a semiconductor material such as silicon, GaAs, or SiC.

[0027] The semiconductor element E is provided on the front surface F1 of the substrate S. The semiconductor element E is, for example, a power semiconductor element provided on an epitaxial layer.

[0028] The rear surface insulating film I is provided on the rear surface F2 of the substrate S. The rear surface insulating film I is a film formed on the rear surface F2 when the semiconductor element E is formed on the front surface F1, and is removed in the subsequent back grinding process. The rear surface insulating film I is formed on the rear surface F2, but is hardly formed on the side surface F3. The rear surface insulating film I is composed of an insulating material such as a silicon oxide film.

[0029] The semiconductor wafer W may not be bevel ground as shown in FIG. 3, or may be bevel ground as shown in FIG.

[0030] Next, clamp driver 50 moves clamp electrodes 30a and 30b, and clamp electrodes 30a and 30b clamp semiconductor wafer W from side surface F3 as shown in Fig. 1 (S20). As a result, clamp electrodes 30a and 30b come into direct contact with side surface F3 of semiconductor wafer W and are electrically connected to substrate S. Clamp electrodes 30a and 30b also have the function of fixing semiconductor wafer W within the XY plane.

[0031] Next, the probe card driving unit 52 moves the probe card 20 above the semiconductor wafer W, and brings the probe needles 21 into contact with any semiconductor element E on the front surface F1 of the semiconductor wafer W (S30). As a result, the probe needles 21 are electrically connected to the semiconductor element E.

[0032] Next, the measurement unit 70 applies power between the probe needle 21 and the clamp electrodes 30a, 30b. This applies a voltage to the semiconductor element E and the substrate S. The measurement unit 70 measures various electrical characteristics of the semiconductor element E (S40). At this time, even if the substrate S is electrically insulated from the stage 10 by the rear surface insulating film I, the clamp electrodes 30a, 30b are electrically connected to the side surface F3 of the substrate S. Therefore, the measurement unit 70 can obtain the electrical characteristics of the semiconductor element E via the clamp electrodes 30a, 30b.

[0033] Thereafter, the transfer arm 80 transfers the semiconductor wafer W from the stage 10 (S50), and the series of measurement processes is completed.

[0034] In this manner, the probing device 1 according to the present embodiment includes the clamp electrodes 30a and 30b, and is configured to be movable on the stage 10 within the XY plane from the outside of the stage 10 toward the center. As a result, the clamp electrodes 30a and 30b can come into contact with the side surface F3 of the semiconductor wafer W on the stage 10, and function as electrodes electrically connected to the substrate S. As a result, even if the rear surface insulating film I covers the rear surface F2 of the semiconductor wafer W, the clamp electrodes 30a and 30b function equivalently to the rear surface electrode of the semiconductor wafer W, and the semiconductor element E on the front surface F1 side of the semiconductor wafer W can be tested. The clamp electrodes 30a and 30b also function to fix the semiconductor wafer W at a predetermined position on the stage 10.

[0035] In the probing device 1 according to this embodiment, a back surface insulating film I covers the back surface F2 of the semiconductor wafer W. The back surface insulating film I is made of the same material as the silicon oxide film that covers the semiconductor element E on the front surface F1 side. This suppresses warping of the semiconductor wafer W, and allows the semiconductor wafer W to be easily transported to a subsequent process.

[0036] After the inspection process of the semiconductor wafer W in the probing device 1, the semiconductor wafer W is diced into individual semiconductor chips CH through the processes shown in FIGS.

[0037] 5 to 9 are cross-sectional views showing the manufacturing process of a semiconductor device after the semiconductor wafer W is inspected.

[0038] After the inspection process of the semiconductor wafer W, as shown in Fig. 5, a support substrate SS is attached to the front surface F1 side of the semiconductor wafer W. The support substrate SS is, for example, a glass substrate, and is attached with an adhesive onto the silicon oxide film that covers the semiconductor element E. At this time, a rear surface insulating film I is also formed on the rear surface F2 side. Therefore, the semiconductor wafer W does not warp much, making it easy to transport or attach the support substrate SS.

[0039] Next, the semiconductor wafer W is inverted as shown in Fig. 6. Next, the rear surface insulating film I and the substrate S are polished from the rear surface F2 side by using a CMP (Chemical Mechanical Polishing) method or an etching method. As a result, the rear surface insulating film I is removed and the substrate S is thinned.

[0040] 7, a material for the back electrode RE is deposited by sputtering or the like on the back surface F2 of the semiconductor wafer W. The back electrode RE is made of a low-resistance metal material such as gold, copper, or aluminum.

[0041] Next, a dicing tape DT is attached to the back surface F2 side of the semiconductor wafer W. The dicing tape DT is made of, for example, a flexible resin, and is attached onto the back surface electrode RE.

[0042] 8, the semiconductor wafer W is turned over again. Next, the support substrate SS is peeled off from the semiconductor wafer W.

[0043] 9, the semiconductor wafer W is divided into a plurality of semiconductor chips CH using a dicing blade or a laser. The semiconductor chips CH are picked up in another device and packaged in an assembly process.

[0044] Second embodiment 10 is a plan view showing a configuration example of a clamp electrode according to the second embodiment. When viewed from the Z direction, clamp electrodes 30a, 30b are arranged on both sides (±X directions) of a semiconductor wafer W. When clamping the semiconductor wafer W, clamp electrode 30a located in the +X direction of the semiconductor wafer W moves in the -X direction, and clamp electrode 30b located in the -X direction of the semiconductor wafer W moves in the +X direction.

[0045] Furthermore, the clamp electrodes 30a, 30b have a shape that conforms to the outer shape of the semiconductor wafer W at the contact surface with the semiconductor wafer W. For example, the clamp electrodes 30a, 30b have a substantially arcuate shape that is the same as the outer shape of the semiconductor wafer W at the contact surface with the semiconductor wafer W. This allows the clamp electrodes 30a, 30b to sandwich and fix the semiconductor wafer W between them and to be connected to the substrate S over a large area. This allows the contact resistance between the clamp electrodes 30a, 30b and the substrate S to be reduced.

[0046] When clamping the semiconductor wafer W, both clamp electrodes 30a, 30b may move to clamp the semiconductor wafer W. However, one of clamp electrodes 30a, 30b may be fixed at a predetermined position, and the other may move to one side to clamp the semiconductor wafer W. In this case, the semiconductor wafer W moves somewhat slippery on the stage 10, but this does not hinder measurement of the electrical characteristics of the semiconductor element.

[0047] Third embodiment 11 is a plan view showing a configuration example of the clamp electrodes according to the third embodiment. The clamp electrodes 30a, 30b, and 30c each have a pin shape. In a cross section parallel to the XY plane, the clamp electrodes 30a, 30b, and 30c may have a shape of, for example, a cylinder, an elliptical cylinder, or a polygonal cylinder. When viewed from the Z direction, the clamp electrodes 30a, 30b, and 30c are evenly arranged in three directions of the semiconductor wafer W, and sandwich the semiconductor wafer W from three directions. When clamping the semiconductor wafer W, the clamp electrodes 30a, 30b, and 30c of the semiconductor wafer W move toward the semiconductor wafer W to clamp the semiconductor wafer W.

[0048] The clamp electrodes 30a, 30b and 30c are each pin-shaped and clamp the semiconductor wafer W from three directions, making it possible to clamp semiconductor wafers W having various sizes or shapes.

[0049] When clamping the semiconductor wafer W, all of the clamp electrodes 30a, 30b, and 30c may move to clamp the semiconductor wafer W. However, at least one of the clamp electrodes 30a, 30b, and 30c may be fixed at a predetermined position, and the other clamp electrodes may move to clamp the semiconductor wafer W. In this case, the semiconductor wafer W moves somewhat slippery on the stage 10, but this does not affect the measurement of the electrical characteristics of the semiconductor element.

[0050] Furthermore, the number of clamp electrodes may be four or more. Even in this case, the clamp electrodes are preferably disposed around the semiconductor wafer W at equal intervals.

[0051] (Fourth embodiment) 12 is a cross-sectional view showing a configuration example of a clamp electrode according to the fourth embodiment. The thickness T30 of the clamp electrodes 30a, 30b in the Z direction is thicker than the thickness of the semiconductor wafer W or the thickness Tw of the substrate S. Therefore, the clamp electrodes 30a, 30b can contact the entire side surface of the semiconductor wafer W (side surface of the substrate S) in the Z direction, and the contact surface between the clamp electrodes 30a, 30b and the semiconductor wafer W can be widened. This allows the clamp electrodes 30a, 30b to be connected to the substrate S with low resistance. The other configurations of the fourth embodiment may be the same as those of the first embodiment. As a result, the fourth embodiment can obtain the same effects as those of the first embodiment.

[0052] Furthermore, the clamp electrodes 30a, 30b according to the fourth embodiment may be applied to any of the clamp electrodes 30a and 30b, or 30a to 30c, according to the second and third embodiments, so that the fourth embodiment can also obtain the effects of the second or third embodiment.

[0053] Fifth embodiment 13 is a cross-sectional view showing a configuration example of the clamp electrodes according to the fifth embodiment. When the clamp electrodes 30a, 30b contact the entire side surface of the semiconductor wafer W in the Z direction, there is a possibility that the clamp electrodes 30a, 30b may short-circuit to the semiconductor element on the front surface F1 side.

[0054] Therefore, in the fifth embodiment, the thickness T30 of the clamp electrodes 30a, 30b in the Z direction is smaller than the thickness of the semiconductor wafer W or the thickness Tw of the substrate S. Furthermore, insulating layers 31a, 31b are provided on the clamp electrodes 30a, 30b. The insulating layers 31a, 31b are made of a non-conductive material such as ceramic, resin, or the like.

[0055] In the Z direction, the thickness T30 of the clamp electrodes 30a, 30b is smaller than the thickness of the semiconductor wafer W or the thickness Tw of the substrate S. This makes it possible to prevent the clamp electrodes 30a, 30b from shorting to the semiconductor element on the front surface F1 side. The other configurations of the fifth embodiment may be the same as those of the first embodiment. This allows the fifth embodiment to obtain the same effects as those of the first embodiment.

[0056] Furthermore, the clamp electrodes 30a, 30b according to the fifth embodiment may be applied to any of the clamp electrodes 30a and 30b, or 30a to 30c, according to the second and third embodiments, so that the fifth embodiment can also obtain the effects of the second and third embodiments.

[0057] In addition, in FIG. 12 and FIG. 13, the clamp electrodes 30a, 30b have an L-shape in cross section taken along the ZX plane, but the shape of the clamp electrodes 30a, 30b is not limited to this.

[0058] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0059] 1 Probing device 10 Stages 20 Probe Card 21 Probe needle 30a, 30b, 30c clamp electrodes 40 Stage drive unit 50 Clamp drive unit 52 Probe card drive unit 54 Transport arm drive unit 60 Control section 70 Measuring part 80 Transport Arm

Claims

1. a stage for supporting a semiconductor wafer; A probe card positioned above the stage; a first electrode made of a conductive material, movable on the stage from the outside toward the center of the stage, and capable of contacting a side of the semiconductor wafer.

2. the probe card brings a probe into contact with the semiconductor wafer from above the stage; The semiconductor manufacturing apparatus according to claim 1 , further comprising a measurement unit that applies electric power between the probe and the first electrode to measure electrical characteristics of the semiconductor wafer.

3. 3. The semiconductor manufacturing apparatus according to claim 1, wherein a thickness of the first electrode in a direction perpendicular to a support surface of the stage on which the semiconductor wafer is placed is smaller than a thickness of the semiconductor wafer.

4. 3. The semiconductor manufacturing apparatus according to claim 1, wherein the first electrode has a shape that conforms to an outer shape of the semiconductor wafer at a surface of contact with the semiconductor wafer when viewed from a direction perpendicular to a support surface of the stage.

5. The semiconductor manufacturing apparatus according to claim 4 , wherein the contact surface of the first electrode has a substantially arcuate shape when viewed from the vertical direction.

6. 2. The semiconductor manufacturing apparatus according to claim 1, further comprising a second electrode that sandwiches the semiconductor wafer between the first electrode and a second electrode when viewed from a direction perpendicular to a support surface of the stage on which the semiconductor wafer is placed.

7. 7. The semiconductor manufacturing apparatus according to claim 6, wherein a thickness of the first and second electrodes in the vertical direction is smaller than a thickness of the semiconductor wafer.

8. 2. The semiconductor manufacturing apparatus according to claim 1, further comprising an insulating layer made of a non-conductive material and provided on the first electrode.

9. a second electrode and a third electrode that sandwich the semiconductor wafer between the first electrode and the second electrode and from three directions when viewed from a direction perpendicular to a support surface of the stage on which the semiconductor wafer is placed, 2. The semiconductor manufacturing apparatus according to claim 1, wherein the first to third electrodes have a pin shape.

10. 10. The semiconductor manufacturing apparatus according to claim 9, wherein a thickness of the first to third electrodes in a direction perpendicular to a support surface of the stage that supports the semiconductor wafer is thinner than a thickness of the semiconductor wafer.

Images