METHOD AND DEVICE FOR ELECTRICALLY CONTACTING COMPONENTS IN A SEMICONDUCTOR WAFER

Abstract

A method for electrically contacting components in a semiconductor wafer includes providing a flexible board comprising a first main surface on which a plurality of conductor tracks are arranged, positioning the board with respect to a semiconductor wafer such that the first main surface of the board faces the semiconductor wafer, the board is bent and pressed onto the semiconductor wafer in such a way that contact elements of a plurality of components arranged in a row in the semiconductor wafer come into contact with the conductor tracks, and electrical signals are applied to the components through the conductor tracks.

Claims

1. A method for electrically contacting components in a semiconductor wafer, wherein a flexible board is provided comprising a first main surface on which a plurality of conductor tracks are arranged, the board is arranged with respect to a semiconductor wafer such that the first main surface of the board faces the semiconductor wafer, the board is bent and pressed onto the semiconductor wafer in such a way that contact elements of a plurality of components arranged in a row in the semiconductor wafer come into contact with the conductor tracks, electrical signals are applied to the components through the conductor tracks, the board is bent by means of a tool pressed on a second main surface of the board opposite to the first main surface, and the tool is moved along the board so that contact elements of different components integrated in the semiconductor wafer successively come into contact with the conductor tracks.

2-3. (canceled)

4. The method according to claim 1, wherein the components each comprise a first contact element on a first main surface of the semiconductor wafer and a second contact element on a second main surface of the semiconductor wafer opposite the first main surface, wherein one conductor track per component comes into contact with the first contact element.

5. The method according to claim 1, wherein the components each comprise a first contact element and a second contact element on a first main surface of the semiconductor wafer, wherein per component one conductor track comes into contact with the first contact element and a further conductor track comes into contact with the second contact element respectively.

6. The method according to claim 1, wherein the components are optoelectronic components configured to emit light.

7. The method according to claim 6, wherein a sensor detects at least a portion of the light emitted by the optoelectronic components.

8. The method according to claim 7, wherein the sensor is moved along the board together with the tool.

9. The method according to claim 7, wherein the sensor is a hyperspectral sensor.

10. The method according to claim 1, wherein the board and/or the conductor tracks are at least partially transparent.

11. The method according to claim 1, wherein a current is applied to one end of one of the conductor tracks and an electrical potential is measured at the other end of the conductor track.

12. A device for electrically contacting components in a semiconductor wafer, comprising: a holder configured to hold a semiconductor wafer, a flexible board comprising a first main surface on which a plurality of conductor tracks are arranged, and a unit for generating electrical signals, wherein the board is arranged with respect to the semiconductor wafer such that the first main surface of the board faces the semiconductor wafer, wherein the board is bent and configured to be pressed onto a semiconductor wafer such that contact elements of a plurality of components arranged in a row in the semiconductor wafer come into contact with the conductor tracks, wherein the electrical signal generating unit applies electrical signals to the components through the conductor tracks, wherein the device comprises a tool pressed on a second main surface of the board opposite the first main surface to bend the board, and wherein the tool is moved along the board so that contact elements of different components integrated in the semiconductor wafer successively come into contact with the conductor tracks.

13-14. (canceled)

15. The device according to claim 12, wherein the electrical signal generation unit applies a current to one end of one of the conductor tracks and a unit for measuring an electrical potential is connected to the other end of the conductor track.

Description

[0038] In the following, embodiments of the invention are explained in more detail with reference to the accompanying drawings. In these schematically show:

[0039] FIG. 1 an illustration of an embodiment of a device for electrically contacting components in a semiconductor wafer;

[0040] FIG. 2 a perspective view of the device of FIG. 1;

[0041] FIG. 3 an illustration of an embodiment of a method for electrically contacting components in a semiconductor wafer;

[0042] FIG. 4 an illustration of the device of FIG. 1 during operation of the device; and

[0043] FIG. 5 an illustration of a further embodiment of a device for electrically contacting components in a semiconductor wafer.

[0044] In the following detailed description, reference is made to the accompanying drawings, which form a part of this description and in which specific embodiments in which the invention may be practiced are shown for illustrative purposes. Since components of embodiments may be positioned in a number of different orientations, the directional terminology is for illustrative purposes and is not limiting in any way. It is understood that other embodiments may be used and structural or logical changes may be made without departing from the scope of protection. It is understood that the features of the various embodiments described herein may be combined with each other, unless specifically indicated otherwise. Therefore, the following detailed description is not to be construed in a limiting sense. In the figures, identical or similar elements are provided with identical reference signs where appropriate.

[0045] FIG. 1 shows the schematic structure of a device 10 used for electrically contacting and checking components 11 integrated in a semiconductor wafer 12.

[0046] The device 10 comprises a holder 13, which holds the semiconductor wafer 12, and a flexible board 14, for example a flexible printed circuit board, comprising a first main surface 15 and a second main surface 16 opposite the first main surface 15. The board 14 is arranged with respect to the semiconductor wafer 12 in such a way that the first main surface 15 of the board 14 faces the semiconductor wafer 12. A tool 17, for example a squeegee, which in particular has a blade geometry, is pressed onto the second main surface 16, as a result of which the bending of the originally, for example, flat board 14 in the direction of the semiconductor wafer 12, as shown in FIG. 1, results and contact is thus made between the main surface 15 and the contact elements of the semiconductor wafer 12.

[0047] FIG. 2 shows a perspective view of the board 14 as well as the tool 17 in a top view. In the present embodiment, the board body of the board 14 is made of a substantially transparent material. A plurality of conductor tracks 20 extending parallel to each other are arranged on the first main surface 15 of the board 14, which can be seen in FIG. 2 through the transparent material of the board body.

[0048] The force applied to the board 14 by the tool 17 causes the conductor tracks 20 to come into contact with contact elements of a plurality of components 11 integrated into the semiconductor wafer 12, which are not shown in the figures.

[0049] The semiconductor wafer 12 and the board 14 are oriented with respect to each other so that the conductor tracks 20 at any one time come into contact only with the contact elements of components 11 arranged in the same row of the semiconductor wafer 12. In FIG. 1, the conductor tracks 20 are in contact with the contact elements of the component 11.1 shown in FIG. 1 and of other components 11 arranged in the same row. The row extends perpendicular to the drawing plane.

[0050] The device 10 further comprises a measuring unit 21 electrically connected to the two respective ends or end portions of the conductor tracks 20. The measuring unit 21 applies a predetermined current into one end of a respective conductor track 20. The applied current flows through the component 11 in contact with the conductor track 20 and through a terminal of the holder 13, which is in contact with the bottom side of the semiconductor wafer 12 and a contact element of the component 11 located there, to the measuring unit 21, which is electrically connected to the holder 13 via a connection 24. A voltage measuring device integrated in the measuring unit 21 is connected to the other end of the relevant conductor track, which measures the voltage dropping across the component 11.

[0051] The measuring unit 21 is connected to an evaluation unit 22, to which the voltage values recorded by the measuring unit 21 are transmitted.

[0052] The components 11 are optoelectronic components that emit light of a specific wavelength or range of wavelengths when the current generated by the measuring unit 21 is applied to them.

[0053] A sensor 23, in particular a hyperspectral sensor, measures the intensity and spectrum emitted by the components 11 and transmits the corresponding measured values to the evaluation unit 22.

[0054] FIG. 3 shows the process steps of a method 30 carried out with the device 10 for electrically contacting the components 11 in the semiconductor wafer 12.

[0055] In step 31, the semiconductor wafer 12 is provided and received in the holder 13.

[0056] In step 32, the tool 17 is pressed onto the second main surface 16 of the flexible board 14 to bring the conductor tracks 20 arranged on the first main surface 15 of the board 14 into contact with a row of components 11.

[0057] In step 33, the measuring unit 21 and the sensor 23 are used to record the measured values described above and transmit them to the evaluation unit 22.

[0058] In step 34, the tool 17 is moved further so that the components 11 of the next row of the semiconductor wafer 12 are now in contact with the conductor tracks 20. This is shown by way of example in FIG. 4. While in FIG. 1 the conductor tracks 20 contact the component 11.1 as well as the other components arranged in the same row, in FIG. 4 the tool 17 has been moved by one row so that now the neighboring component 11.2 as well as the other components arranged in the same row are in contact with the conductor tracks 20.

[0059] In step 35, the measuring unit 21 and the sensor 23 record the measured values for the now contacted components 11 and transmit them to the evaluation unit 22.

[0060] In the measurements described, the sensor 23 is moved together with the tool 17 so that the sensor 23 is always the same distance from the components 11 to be examined.

[0061] The described procedure can be continued until all the components 11 of the semiconductor wafer 12 to be checked have been tested. The evaluation unit 22 can identify those components 11 whose function is impaired.

[0062] FIG. 5 shows the schematic structure of a device 40 for electrically contacting and checking components 11. In this embodinvent, the flexible board 14 with the line structure consisting of the conductor tracks 20 is clamped in a screen printing frame 41. The screen printing frame 42 is integrated into an automatic stencil printing machine, which is not shown. The semiconductor wafer 12 is arranged below the screen printing frame 41. The electrical data are recorded by a data acquisition card 42 and transmitted to the evaluation unit 22, which is designed as a computer.

[0063] The squeegee, which is not shown in FIG. 5, presses the board 14 in the direction of the semiconductor wafer 12 in order to be able to contact individual components 11. The screen printing frame 41 enables the exact and, in particular, automatic alignment of the conductor tracks 20 to the components 11. The number of conductor tracks 20 can correspond to the maximum number of components 11 of a line of the semiconductor wafer 12. Electrodes coupled to the conductor tracks 20 are connected to the inputs of the data acquisition board 42 in such a way that a 3-point measurement is possible.

[0064] The contacting time per component 11 during the execution of the measurements depends on the size of an individual component 11 as well as the squeegee speed and is in the range of a few milliseconds. The pressure of the squeegee on the flexible board 14 as well as the speed at which the squeegee moves over the flexible board 14 can be adjusted. In parallel with the squeegee, a hyperspectral line scan camera moves over the semiconductor wafer 12 and measures intensity and spectrum for one line at a time. From this, the evaluation unit 22 can determine the optical data for each component 11.

LIST OF REFERENCE SIGNS

[0065] 10 device [0066] 11 component [0067] 11.1 component [0068] 11.2 component [0069] 12 semiconductor wafer [0070] 13 holder [0071] 14 board [0072] 15 first main surface [0073] 16 second main surface [0074] 17 tool [0075] 20 conductor track [0076] 21 measuring unit [0077] 22 evaluation unit [0078] 23 sensor [0079] 24 connection [0080] 30 method [0081] 31 Step [0082] 32 Step [0083] 33 Step [0084] 34 Step [0085] 35 Step [0086] 40 device [0087] 41 screen printing frame [0088] 42 data acquisition map